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fs/dcache.c
77 KB
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/* * fs/dcache.c * * Complete reimplementation * (C) 1997 Thomas Schoebel-Theuer, * with heavy changes by Linus Torvalds */ /* * Notes on the allocation strategy: * * The dcache is a master of the icache - whenever a dcache entry * exists, the inode will always exist. "iput()" is done either when * the dcache entry is deleted or garbage collected. */ |
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#include <linux/syscalls.h> #include <linux/string.h> #include <linux/mm.h> #include <linux/fs.h> |
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#include <linux/fsnotify.h> |
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#include <linux/slab.h> #include <linux/init.h> |
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#include <linux/hash.h> #include <linux/cache.h> #include <linux/module.h> #include <linux/mount.h> #include <linux/file.h> #include <asm/uaccess.h> #include <linux/security.h> #include <linux/seqlock.h> #include <linux/swap.h> #include <linux/bootmem.h> |
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#include <linux/fs_struct.h> |
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#include <linux/hardirq.h> |
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#include <linux/bit_spinlock.h> #include <linux/rculist_bl.h> |
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#include <linux/prefetch.h> |
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#include <linux/ratelimit.h> |
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#include "internal.h" |
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#include "mount.h" |
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|
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/* * Usage: |
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* dcache->d_inode->i_lock protects: * - i_dentry, d_alias, d_inode of aliases |
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* dcache_hash_bucket lock protects: * - the dcache hash table * s_anon bl list spinlock protects: * - the s_anon list (see __d_drop) |
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* dcache_lru_lock protects: * - the dcache lru lists and counters * d_lock protects: * - d_flags * - d_name * - d_lru |
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* - d_count |
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* - d_unhashed() |
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* - d_parent and d_subdirs * - childrens' d_child and d_parent |
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* - d_alias, d_inode |
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* * Ordering: |
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* dentry->d_inode->i_lock |
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* dentry->d_lock * dcache_lru_lock |
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* dcache_hash_bucket lock * s_anon lock |
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* |
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* If there is an ancestor relationship: * dentry->d_parent->...->d_parent->d_lock * ... * dentry->d_parent->d_lock * dentry->d_lock * * If no ancestor relationship: |
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* if (dentry1 < dentry2) * dentry1->d_lock * dentry2->d_lock */ |
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int sysctl_vfs_cache_pressure __read_mostly = 100; |
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EXPORT_SYMBOL_GPL(sysctl_vfs_cache_pressure); |
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static __cacheline_aligned_in_smp DEFINE_SPINLOCK(dcache_lru_lock); |
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__cacheline_aligned_in_smp DEFINE_SEQLOCK(rename_lock); |
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|
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EXPORT_SYMBOL(rename_lock); |
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|
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static struct kmem_cache *dentry_cache __read_mostly; |
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/* * This is the single most critical data structure when it comes * to the dcache: the hashtable for lookups. Somebody should try * to make this good - I've just made it work. * * This hash-function tries to avoid losing too many bits of hash * information, yet avoid using a prime hash-size or similar. */ #define D_HASHBITS d_hash_shift #define D_HASHMASK d_hash_mask |
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static unsigned int d_hash_mask __read_mostly; static unsigned int d_hash_shift __read_mostly; |
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|
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static struct hlist_bl_head *dentry_hashtable __read_mostly; |
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|
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static inline struct hlist_bl_head *d_hash(struct dentry *parent, |
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unsigned long hash) { hash += ((unsigned long) parent ^ GOLDEN_RATIO_PRIME) / L1_CACHE_BYTES; hash = hash ^ ((hash ^ GOLDEN_RATIO_PRIME) >> D_HASHBITS); return dentry_hashtable + (hash & D_HASHMASK); } |
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/* Statistics gathering. */ struct dentry_stat_t dentry_stat = { .age_limit = 45, }; |
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static DEFINE_PER_CPU(unsigned int, nr_dentry); |
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#if defined(CONFIG_SYSCTL) && defined(CONFIG_PROC_FS) |
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static int get_nr_dentry(void) { int i; int sum = 0; for_each_possible_cpu(i) sum += per_cpu(nr_dentry, i); return sum < 0 ? 0 : sum; } |
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int proc_nr_dentry(ctl_table *table, int write, void __user *buffer, size_t *lenp, loff_t *ppos) { |
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dentry_stat.nr_dentry = get_nr_dentry(); |
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return proc_dointvec(table, write, buffer, lenp, ppos); } #endif |
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static void __d_free(struct rcu_head *head) |
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{ |
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struct dentry *dentry = container_of(head, struct dentry, d_u.d_rcu); |
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WARN_ON(!list_empty(&dentry->d_alias)); |
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if (dname_external(dentry)) kfree(dentry->d_name.name); kmem_cache_free(dentry_cache, dentry); } /* |
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* no locks, please. |
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*/ static void d_free(struct dentry *dentry) { |
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BUG_ON(dentry->d_count); |
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this_cpu_dec(nr_dentry); |
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if (dentry->d_op && dentry->d_op->d_release) dentry->d_op->d_release(dentry); |
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|
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/* if dentry was never visible to RCU, immediate free is OK */ if (!(dentry->d_flags & DCACHE_RCUACCESS)) |
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__d_free(&dentry->d_u.d_rcu); |
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else |
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call_rcu(&dentry->d_u.d_rcu, __d_free); |
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} |
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/** * dentry_rcuwalk_barrier - invalidate in-progress rcu-walk lookups |
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* @dentry: the target dentry |
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* After this call, in-progress rcu-walk path lookup will fail. This * should be called after unhashing, and after changing d_inode (if * the dentry has not already been unhashed). */ static inline void dentry_rcuwalk_barrier(struct dentry *dentry) { assert_spin_locked(&dentry->d_lock); /* Go through a barrier */ write_seqcount_barrier(&dentry->d_seq); } |
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/* * Release the dentry's inode, using the filesystem |
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* d_iput() operation if defined. Dentry has no refcount * and is unhashed. |
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*/ |
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static void dentry_iput(struct dentry * dentry) |
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__releases(dentry->d_lock) |
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__releases(dentry->d_inode->i_lock) |
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{ struct inode *inode = dentry->d_inode; if (inode) { dentry->d_inode = NULL; list_del_init(&dentry->d_alias); spin_unlock(&dentry->d_lock); |
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spin_unlock(&inode->i_lock); |
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if (!inode->i_nlink) fsnotify_inoderemove(inode); |
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if (dentry->d_op && dentry->d_op->d_iput) dentry->d_op->d_iput(dentry, inode); else iput(inode); } else { spin_unlock(&dentry->d_lock); |
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} } |
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/* |
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* Release the dentry's inode, using the filesystem * d_iput() operation if defined. dentry remains in-use. */ static void dentry_unlink_inode(struct dentry * dentry) __releases(dentry->d_lock) |
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__releases(dentry->d_inode->i_lock) |
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{ struct inode *inode = dentry->d_inode; dentry->d_inode = NULL; list_del_init(&dentry->d_alias); dentry_rcuwalk_barrier(dentry); spin_unlock(&dentry->d_lock); |
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spin_unlock(&inode->i_lock); |
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if (!inode->i_nlink) fsnotify_inoderemove(inode); if (dentry->d_op && dentry->d_op->d_iput) dentry->d_op->d_iput(dentry, inode); else iput(inode); } /* |
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* dentry_lru_(add|del|prune|move_tail) must be called with d_lock held. |
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*/ static void dentry_lru_add(struct dentry *dentry) { |
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if (list_empty(&dentry->d_lru)) { |
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spin_lock(&dcache_lru_lock); |
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list_add(&dentry->d_lru, &dentry->d_sb->s_dentry_lru); dentry->d_sb->s_nr_dentry_unused++; |
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dentry_stat.nr_unused++; |
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spin_unlock(&dcache_lru_lock); |
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} |
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} |
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static void __dentry_lru_del(struct dentry *dentry) { list_del_init(&dentry->d_lru); |
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dentry->d_flags &= ~DCACHE_SHRINK_LIST; |
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dentry->d_sb->s_nr_dentry_unused--; dentry_stat.nr_unused--; } |
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/* * Remove a dentry with references from the LRU. */ |
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static void dentry_lru_del(struct dentry *dentry) { if (!list_empty(&dentry->d_lru)) { |
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spin_lock(&dcache_lru_lock); __dentry_lru_del(dentry); spin_unlock(&dcache_lru_lock); |
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} } |
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/* * Remove a dentry that is unreferenced and about to be pruned * (unhashed and destroyed) from the LRU, and inform the file system. * This wrapper should be called _prior_ to unhashing a victim dentry. */ static void dentry_lru_prune(struct dentry *dentry) { if (!list_empty(&dentry->d_lru)) { if (dentry->d_flags & DCACHE_OP_PRUNE) dentry->d_op->d_prune(dentry); spin_lock(&dcache_lru_lock); __dentry_lru_del(dentry); spin_unlock(&dcache_lru_lock); } } |
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static void dentry_lru_move_list(struct dentry *dentry, struct list_head *list) |
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{ |
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spin_lock(&dcache_lru_lock); |
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if (list_empty(&dentry->d_lru)) { |
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list_add_tail(&dentry->d_lru, list); |
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dentry->d_sb->s_nr_dentry_unused++; |
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dentry_stat.nr_unused++; |
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} else { |
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list_move_tail(&dentry->d_lru, list); |
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} |
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spin_unlock(&dcache_lru_lock); |
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} |
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/** * d_kill - kill dentry and return parent * @dentry: dentry to kill |
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* @parent: parent dentry |
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* |
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* The dentry must already be unhashed and removed from the LRU. |
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* * If this is the root of the dentry tree, return NULL. |
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* |
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* dentry->d_lock and parent->d_lock must be held by caller, and are dropped by * d_kill. |
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*/ |
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static struct dentry *d_kill(struct dentry *dentry, struct dentry *parent) |
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__releases(dentry->d_lock) |
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__releases(parent->d_lock) |
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__releases(dentry->d_inode->i_lock) |
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{ |
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list_del(&dentry->d_u.d_child); |
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/* * Inform try_to_ascend() that we are no longer attached to the * dentry tree */ dentry->d_flags |= DCACHE_DISCONNECTED; |
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if (parent) spin_unlock(&parent->d_lock); |
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dentry_iput(dentry); |
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/* * dentry_iput drops the locks, at which point nobody (except * transient RCU lookups) can reach this dentry. */ |
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d_free(dentry); |
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return parent; |
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} |
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/* * Unhash a dentry without inserting an RCU walk barrier or checking that * dentry->d_lock is locked. The caller must take care of that, if * appropriate. */ static void __d_shrink(struct dentry *dentry) { if (!d_unhashed(dentry)) { struct hlist_bl_head *b; if (unlikely(dentry->d_flags & DCACHE_DISCONNECTED)) b = &dentry->d_sb->s_anon; else b = d_hash(dentry->d_parent, dentry->d_name.hash); hlist_bl_lock(b); __hlist_bl_del(&dentry->d_hash); dentry->d_hash.pprev = NULL; hlist_bl_unlock(b); } } |
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/** * d_drop - drop a dentry * @dentry: dentry to drop * * d_drop() unhashes the entry from the parent dentry hashes, so that it won't * be found through a VFS lookup any more. Note that this is different from * deleting the dentry - d_delete will try to mark the dentry negative if * possible, giving a successful _negative_ lookup, while d_drop will * just make the cache lookup fail. * * d_drop() is used mainly for stuff that wants to invalidate a dentry for some * reason (NFS timeouts or autofs deletes). * * __d_drop requires dentry->d_lock. */ void __d_drop(struct dentry *dentry) { |
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if (!d_unhashed(dentry)) { |
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__d_shrink(dentry); |
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dentry_rcuwalk_barrier(dentry); |
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} } EXPORT_SYMBOL(__d_drop); void d_drop(struct dentry *dentry) { |
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spin_lock(&dentry->d_lock); __d_drop(dentry); spin_unlock(&dentry->d_lock); |
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} EXPORT_SYMBOL(d_drop); |
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/* |
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* d_clear_need_lookup - drop a dentry from cache and clear the need lookup flag * @dentry: dentry to drop * * This is called when we do a lookup on a placeholder dentry that needed to be * looked up. The dentry should have been hashed in order for it to be found by * the lookup code, but now needs to be unhashed while we do the actual lookup * and clear the DCACHE_NEED_LOOKUP flag. */ void d_clear_need_lookup(struct dentry *dentry) { spin_lock(&dentry->d_lock); __d_drop(dentry); dentry->d_flags &= ~DCACHE_NEED_LOOKUP; spin_unlock(&dentry->d_lock); } EXPORT_SYMBOL(d_clear_need_lookup); /* |
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* Finish off a dentry we've decided to kill. * dentry->d_lock must be held, returns with it unlocked. * If ref is non-zero, then decrement the refcount too. * Returns dentry requiring refcount drop, or NULL if we're done. */ static inline struct dentry *dentry_kill(struct dentry *dentry, int ref) __releases(dentry->d_lock) { |
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struct inode *inode; |
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struct dentry *parent; |
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inode = dentry->d_inode; if (inode && !spin_trylock(&inode->i_lock)) { |
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relock: spin_unlock(&dentry->d_lock); cpu_relax(); return dentry; /* try again with same dentry */ } if (IS_ROOT(dentry)) parent = NULL; else parent = dentry->d_parent; if (parent && !spin_trylock(&parent->d_lock)) { |
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if (inode) spin_unlock(&inode->i_lock); |
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goto relock; } |
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|
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if (ref) dentry->d_count--; |
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/* * if dentry was on the d_lru list delete it from there. * inform the fs via d_prune that this dentry is about to be * unhashed and destroyed. */ dentry_lru_prune(dentry); |
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/* if it was on the hash then remove it */ __d_drop(dentry); return d_kill(dentry, parent); } |
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/* * This is dput * * This is complicated by the fact that we do not want to put * dentries that are no longer on any hash chain on the unused * list: we'd much rather just get rid of them immediately. * * However, that implies that we have to traverse the dentry * tree upwards to the parents which might _also_ now be * scheduled for deletion (it may have been only waiting for * its last child to go away). * * This tail recursion is done by hand as we don't want to depend * on the compiler to always get this right (gcc generally doesn't). * Real recursion would eat up our stack space. */ /* * dput - release a dentry * @dentry: dentry to release * * Release a dentry. This will drop the usage count and if appropriate * call the dentry unlink method as well as removing it from the queues and * releasing its resources. If the parent dentries were scheduled for release * they too may now get deleted. |
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*/ |
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void dput(struct dentry *dentry) { if (!dentry) return; repeat: |
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if (dentry->d_count == 1) |
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might_sleep(); |
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spin_lock(&dentry->d_lock); |
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BUG_ON(!dentry->d_count); if (dentry->d_count > 1) { dentry->d_count--; |
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457 |
spin_unlock(&dentry->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
458 459 |
return; } |
fb045adb9 fs: dcache reduce... |
460 |
if (dentry->d_flags & DCACHE_OP_DELETE) { |
1da177e4c Linux-2.6.12-rc2 |
461 |
if (dentry->d_op->d_delete(dentry)) |
61f3dee4a fs: dcache reduce... |
462 |
goto kill_it; |
1da177e4c Linux-2.6.12-rc2 |
463 |
} |
265ac9023 fs: improve DCACH... |
464 |
|
1da177e4c Linux-2.6.12-rc2 |
465 466 467 |
/* Unreachable? Get rid of it */ if (d_unhashed(dentry)) goto kill_it; |
265ac9023 fs: improve DCACH... |
468 |
|
44396f4b5 fs: add a DCACHE_... |
469 470 471 472 473 474 475 |
/* * If this dentry needs lookup, don't set the referenced flag so that it * is more likely to be cleaned up by the dcache shrinker in case of * memory pressure. */ if (!d_need_lookup(dentry)) dentry->d_flags |= DCACHE_REFERENCED; |
a4633357a fs: clean up dent... |
476 |
dentry_lru_add(dentry); |
265ac9023 fs: improve DCACH... |
477 |
|
61f3dee4a fs: dcache reduce... |
478 479 |
dentry->d_count--; spin_unlock(&dentry->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
480 |
return; |
d52b90864 fix quadratic beh... |
481 |
kill_it: |
77812a1ef fs: consolidate d... |
482 |
dentry = dentry_kill(dentry, 1); |
d52b90864 fix quadratic beh... |
483 484 |
if (dentry) goto repeat; |
1da177e4c Linux-2.6.12-rc2 |
485 |
} |
ec4f86059 fs/dcache.c: Codi... |
486 |
EXPORT_SYMBOL(dput); |
1da177e4c Linux-2.6.12-rc2 |
487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 |
/** * d_invalidate - invalidate a dentry * @dentry: dentry to invalidate * * Try to invalidate the dentry if it turns out to be * possible. If there are other dentries that can be * reached through this one we can't delete it and we * return -EBUSY. On success we return 0. * * no dcache lock. */ int d_invalidate(struct dentry * dentry) { /* * If it's already been dropped, return OK. */ |
da5029563 fs: dcache scale ... |
505 |
spin_lock(&dentry->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
506 |
if (d_unhashed(dentry)) { |
da5029563 fs: dcache scale ... |
507 |
spin_unlock(&dentry->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
508 509 510 511 512 513 514 |
return 0; } /* * Check whether to do a partial shrink_dcache * to get rid of unused child entries. */ if (!list_empty(&dentry->d_subdirs)) { |
da5029563 fs: dcache scale ... |
515 |
spin_unlock(&dentry->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
516 |
shrink_dcache_parent(dentry); |
da5029563 fs: dcache scale ... |
517 |
spin_lock(&dentry->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
518 519 520 521 522 523 524 525 526 527 528 |
} /* * Somebody else still using it? * * If it's a directory, we can't drop it * for fear of somebody re-populating it * with children (even though dropping it * would make it unreachable from the root, * we might still populate it if it was a * working directory or similar). |
50e696308 vfs: d_invalidate... |
529 530 |
* We also need to leave mountpoints alone, * directory or not. |
1da177e4c Linux-2.6.12-rc2 |
531 |
*/ |
50e696308 vfs: d_invalidate... |
532 533 |
if (dentry->d_count > 1 && dentry->d_inode) { if (S_ISDIR(dentry->d_inode->i_mode) || d_mountpoint(dentry)) { |
1da177e4c Linux-2.6.12-rc2 |
534 |
spin_unlock(&dentry->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
535 536 537 538 539 540 |
return -EBUSY; } } __d_drop(dentry); spin_unlock(&dentry->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
541 542 |
return 0; } |
ec4f86059 fs/dcache.c: Codi... |
543 |
EXPORT_SYMBOL(d_invalidate); |
1da177e4c Linux-2.6.12-rc2 |
544 |
|
b5c84bf6f fs: dcache remove... |
545 |
/* This must be called with d_lock held */ |
dc0474be3 fs: dcache ration... |
546 |
static inline void __dget_dlock(struct dentry *dentry) |
230445078 fs: dcache scale lru |
547 |
{ |
b7ab39f63 fs: dcache scale ... |
548 |
dentry->d_count++; |
230445078 fs: dcache scale lru |
549 |
} |
dc0474be3 fs: dcache ration... |
550 |
static inline void __dget(struct dentry *dentry) |
1da177e4c Linux-2.6.12-rc2 |
551 |
{ |
230445078 fs: dcache scale lru |
552 |
spin_lock(&dentry->d_lock); |
dc0474be3 fs: dcache ration... |
553 |
__dget_dlock(dentry); |
230445078 fs: dcache scale lru |
554 |
spin_unlock(&dentry->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
555 |
} |
b7ab39f63 fs: dcache scale ... |
556 557 558 559 560 |
struct dentry *dget_parent(struct dentry *dentry) { struct dentry *ret; repeat: |
a734eb458 fs: dcache reduce... |
561 562 563 564 565 |
/* * Don't need rcu_dereference because we re-check it was correct under * the lock. */ rcu_read_lock(); |
b7ab39f63 fs: dcache scale ... |
566 |
ret = dentry->d_parent; |
a734eb458 fs: dcache reduce... |
567 568 569 570 |
spin_lock(&ret->d_lock); if (unlikely(ret != dentry->d_parent)) { spin_unlock(&ret->d_lock); rcu_read_unlock(); |
b7ab39f63 fs: dcache scale ... |
571 572 |
goto repeat; } |
a734eb458 fs: dcache reduce... |
573 |
rcu_read_unlock(); |
b7ab39f63 fs: dcache scale ... |
574 575 576 |
BUG_ON(!ret->d_count); ret->d_count++; spin_unlock(&ret->d_lock); |
b7ab39f63 fs: dcache scale ... |
577 578 579 |
return ret; } EXPORT_SYMBOL(dget_parent); |
1da177e4c Linux-2.6.12-rc2 |
580 581 582 583 584 585 586 587 588 589 590 591 |
/** * d_find_alias - grab a hashed alias of inode * @inode: inode in question * @want_discon: flag, used by d_splice_alias, to request * that only a DISCONNECTED alias be returned. * * If inode has a hashed alias, or is a directory and has any alias, * acquire the reference to alias and return it. Otherwise return NULL. * Notice that if inode is a directory there can be only one alias and * it can be unhashed only if it has no children, or if it is the root * of a filesystem. * |
21c0d8fdd [PATCH] knfsd: cl... |
592 |
* If the inode has an IS_ROOT, DCACHE_DISCONNECTED alias, then prefer |
1da177e4c Linux-2.6.12-rc2 |
593 |
* any other hashed alias over that one unless @want_discon is set, |
21c0d8fdd [PATCH] knfsd: cl... |
594 |
* in which case only return an IS_ROOT, DCACHE_DISCONNECTED alias. |
1da177e4c Linux-2.6.12-rc2 |
595 |
*/ |
da5029563 fs: dcache scale ... |
596 |
static struct dentry *__d_find_alias(struct inode *inode, int want_discon) |
1da177e4c Linux-2.6.12-rc2 |
597 |
{ |
da5029563 fs: dcache scale ... |
598 |
struct dentry *alias, *discon_alias; |
1da177e4c Linux-2.6.12-rc2 |
599 |
|
da5029563 fs: dcache scale ... |
600 601 602 603 |
again: discon_alias = NULL; list_for_each_entry(alias, &inode->i_dentry, d_alias) { spin_lock(&alias->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
604 |
if (S_ISDIR(inode->i_mode) || !d_unhashed(alias)) { |
21c0d8fdd [PATCH] knfsd: cl... |
605 |
if (IS_ROOT(alias) && |
da5029563 fs: dcache scale ... |
606 |
(alias->d_flags & DCACHE_DISCONNECTED)) { |
1da177e4c Linux-2.6.12-rc2 |
607 |
discon_alias = alias; |
da5029563 fs: dcache scale ... |
608 |
} else if (!want_discon) { |
dc0474be3 fs: dcache ration... |
609 |
__dget_dlock(alias); |
da5029563 fs: dcache scale ... |
610 611 612 613 614 615 616 617 618 619 620 621 |
spin_unlock(&alias->d_lock); return alias; } } spin_unlock(&alias->d_lock); } if (discon_alias) { alias = discon_alias; spin_lock(&alias->d_lock); if (S_ISDIR(inode->i_mode) || !d_unhashed(alias)) { if (IS_ROOT(alias) && (alias->d_flags & DCACHE_DISCONNECTED)) { |
dc0474be3 fs: dcache ration... |
622 |
__dget_dlock(alias); |
da5029563 fs: dcache scale ... |
623 |
spin_unlock(&alias->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
624 625 626 |
return alias; } } |
da5029563 fs: dcache scale ... |
627 628 |
spin_unlock(&alias->d_lock); goto again; |
1da177e4c Linux-2.6.12-rc2 |
629 |
} |
da5029563 fs: dcache scale ... |
630 |
return NULL; |
1da177e4c Linux-2.6.12-rc2 |
631 |
} |
da5029563 fs: dcache scale ... |
632 |
struct dentry *d_find_alias(struct inode *inode) |
1da177e4c Linux-2.6.12-rc2 |
633 |
{ |
214fda1f6 [PATCH] Optimise ... |
634 635 636 |
struct dentry *de = NULL; if (!list_empty(&inode->i_dentry)) { |
873feea09 fs: dcache per-in... |
637 |
spin_lock(&inode->i_lock); |
214fda1f6 [PATCH] Optimise ... |
638 |
de = __d_find_alias(inode, 0); |
873feea09 fs: dcache per-in... |
639 |
spin_unlock(&inode->i_lock); |
214fda1f6 [PATCH] Optimise ... |
640 |
} |
1da177e4c Linux-2.6.12-rc2 |
641 642 |
return de; } |
ec4f86059 fs/dcache.c: Codi... |
643 |
EXPORT_SYMBOL(d_find_alias); |
1da177e4c Linux-2.6.12-rc2 |
644 645 646 647 648 649 650 |
/* * Try to kill dentries associated with this inode. * WARNING: you must own a reference to inode. */ void d_prune_aliases(struct inode *inode) { |
0cdca3f98 [PATCH] janitor: ... |
651 |
struct dentry *dentry; |
1da177e4c Linux-2.6.12-rc2 |
652 |
restart: |
873feea09 fs: dcache per-in... |
653 |
spin_lock(&inode->i_lock); |
0cdca3f98 [PATCH] janitor: ... |
654 |
list_for_each_entry(dentry, &inode->i_dentry, d_alias) { |
1da177e4c Linux-2.6.12-rc2 |
655 |
spin_lock(&dentry->d_lock); |
b7ab39f63 fs: dcache scale ... |
656 |
if (!dentry->d_count) { |
dc0474be3 fs: dcache ration... |
657 |
__dget_dlock(dentry); |
1da177e4c Linux-2.6.12-rc2 |
658 659 |
__d_drop(dentry); spin_unlock(&dentry->d_lock); |
873feea09 fs: dcache per-in... |
660 |
spin_unlock(&inode->i_lock); |
1da177e4c Linux-2.6.12-rc2 |
661 662 663 664 665 |
dput(dentry); goto restart; } spin_unlock(&dentry->d_lock); } |
873feea09 fs: dcache per-in... |
666 |
spin_unlock(&inode->i_lock); |
1da177e4c Linux-2.6.12-rc2 |
667 |
} |
ec4f86059 fs/dcache.c: Codi... |
668 |
EXPORT_SYMBOL(d_prune_aliases); |
1da177e4c Linux-2.6.12-rc2 |
669 670 |
/* |
77812a1ef fs: consolidate d... |
671 672 673 |
* Try to throw away a dentry - free the inode, dput the parent. * Requires dentry->d_lock is held, and dentry->d_count == 0. * Releases dentry->d_lock. |
d702ccb34 [PATCH] prune_one... |
674 |
* |
77812a1ef fs: consolidate d... |
675 |
* This may fail if locks cannot be acquired no problem, just try again. |
1da177e4c Linux-2.6.12-rc2 |
676 |
*/ |
77812a1ef fs: consolidate d... |
677 |
static void try_prune_one_dentry(struct dentry *dentry) |
31f3e0b3a [patch 1/3] vfs: ... |
678 |
__releases(dentry->d_lock) |
1da177e4c Linux-2.6.12-rc2 |
679 |
{ |
77812a1ef fs: consolidate d... |
680 |
struct dentry *parent; |
d52b90864 fix quadratic beh... |
681 |
|
77812a1ef fs: consolidate d... |
682 |
parent = dentry_kill(dentry, 0); |
d52b90864 fix quadratic beh... |
683 |
/* |
77812a1ef fs: consolidate d... |
684 685 686 687 688 689 690 691 |
* If dentry_kill returns NULL, we have nothing more to do. * if it returns the same dentry, trylocks failed. In either * case, just loop again. * * Otherwise, we need to prune ancestors too. This is necessary * to prevent quadratic behavior of shrink_dcache_parent(), but * is also expected to be beneficial in reducing dentry cache * fragmentation. |
d52b90864 fix quadratic beh... |
692 |
*/ |
77812a1ef fs: consolidate d... |
693 694 695 696 697 698 699 |
if (!parent) return; if (parent == dentry) return; /* Prune ancestors. */ dentry = parent; |
d52b90864 fix quadratic beh... |
700 |
while (dentry) { |
b7ab39f63 fs: dcache scale ... |
701 |
spin_lock(&dentry->d_lock); |
89e605483 fs: dcache reduce... |
702 703 704 705 706 |
if (dentry->d_count > 1) { dentry->d_count--; spin_unlock(&dentry->d_lock); return; } |
77812a1ef fs: consolidate d... |
707 |
dentry = dentry_kill(dentry, 1); |
d52b90864 fix quadratic beh... |
708 |
} |
1da177e4c Linux-2.6.12-rc2 |
709 |
} |
3049cfe24 fs: split __shrin... |
710 |
static void shrink_dentry_list(struct list_head *list) |
1da177e4c Linux-2.6.12-rc2 |
711 |
{ |
da3bbdd46 fix soft lock up ... |
712 |
struct dentry *dentry; |
da3bbdd46 fix soft lock up ... |
713 |
|
ec33679d7 fs: use RCU in sh... |
714 715 |
rcu_read_lock(); for (;;) { |
ec33679d7 fs: use RCU in sh... |
716 717 718 719 720 721 |
dentry = list_entry_rcu(list->prev, struct dentry, d_lru); if (&dentry->d_lru == list) break; /* empty */ spin_lock(&dentry->d_lock); if (dentry != list_entry(list->prev, struct dentry, d_lru)) { spin_unlock(&dentry->d_lock); |
230445078 fs: dcache scale lru |
722 723 |
continue; } |
1da177e4c Linux-2.6.12-rc2 |
724 725 |
/* * We found an inuse dentry which was not removed from |
da3bbdd46 fix soft lock up ... |
726 727 |
* the LRU because of laziness during lookup. Do not free * it - just keep it off the LRU list. |
1da177e4c Linux-2.6.12-rc2 |
728 |
*/ |
b7ab39f63 fs: dcache scale ... |
729 |
if (dentry->d_count) { |
ec33679d7 fs: use RCU in sh... |
730 |
dentry_lru_del(dentry); |
da3bbdd46 fix soft lock up ... |
731 |
spin_unlock(&dentry->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
732 733 |
continue; } |
ec33679d7 fs: use RCU in sh... |
734 |
|
ec33679d7 fs: use RCU in sh... |
735 |
rcu_read_unlock(); |
77812a1ef fs: consolidate d... |
736 737 |
try_prune_one_dentry(dentry); |
ec33679d7 fs: use RCU in sh... |
738 |
rcu_read_lock(); |
da3bbdd46 fix soft lock up ... |
739 |
} |
ec33679d7 fs: use RCU in sh... |
740 |
rcu_read_unlock(); |
3049cfe24 fs: split __shrin... |
741 742 743 |
} /** |
b48f03b31 dcache: use a dis... |
744 745 746 747 748 749 750 |
* prune_dcache_sb - shrink the dcache * @sb: superblock * @count: number of entries to try to free * * Attempt to shrink the superblock dcache LRU by @count entries. This is * done when we need more memory an called from the superblock shrinker * function. |
3049cfe24 fs: split __shrin... |
751 |
* |
b48f03b31 dcache: use a dis... |
752 753 |
* This function may fail to free any resources if all the dentries are in * use. |
3049cfe24 fs: split __shrin... |
754 |
*/ |
b48f03b31 dcache: use a dis... |
755 |
void prune_dcache_sb(struct super_block *sb, int count) |
3049cfe24 fs: split __shrin... |
756 |
{ |
3049cfe24 fs: split __shrin... |
757 758 759 |
struct dentry *dentry; LIST_HEAD(referenced); LIST_HEAD(tmp); |
3049cfe24 fs: split __shrin... |
760 |
|
230445078 fs: dcache scale lru |
761 762 |
relock: spin_lock(&dcache_lru_lock); |
3049cfe24 fs: split __shrin... |
763 764 765 766 |
while (!list_empty(&sb->s_dentry_lru)) { dentry = list_entry(sb->s_dentry_lru.prev, struct dentry, d_lru); BUG_ON(dentry->d_sb != sb); |
230445078 fs: dcache scale lru |
767 768 769 770 771 |
if (!spin_trylock(&dentry->d_lock)) { spin_unlock(&dcache_lru_lock); cpu_relax(); goto relock; } |
b48f03b31 dcache: use a dis... |
772 |
if (dentry->d_flags & DCACHE_REFERENCED) { |
230445078 fs: dcache scale lru |
773 774 |
dentry->d_flags &= ~DCACHE_REFERENCED; list_move(&dentry->d_lru, &referenced); |
3049cfe24 fs: split __shrin... |
775 |
spin_unlock(&dentry->d_lock); |
230445078 fs: dcache scale lru |
776 777 |
} else { list_move_tail(&dentry->d_lru, &tmp); |
eaf5f9073 fix shrink_dcache... |
778 |
dentry->d_flags |= DCACHE_SHRINK_LIST; |
230445078 fs: dcache scale lru |
779 |
spin_unlock(&dentry->d_lock); |
b0d40c92a superblock: intro... |
780 |
if (!--count) |
230445078 fs: dcache scale lru |
781 |
break; |
3049cfe24 fs: split __shrin... |
782 |
} |
ec33679d7 fs: use RCU in sh... |
783 |
cond_resched_lock(&dcache_lru_lock); |
3049cfe24 fs: split __shrin... |
784 |
} |
da3bbdd46 fix soft lock up ... |
785 786 |
if (!list_empty(&referenced)) list_splice(&referenced, &sb->s_dentry_lru); |
230445078 fs: dcache scale lru |
787 |
spin_unlock(&dcache_lru_lock); |
ec33679d7 fs: use RCU in sh... |
788 789 |
shrink_dentry_list(&tmp); |
da3bbdd46 fix soft lock up ... |
790 791 792 |
} /** |
1da177e4c Linux-2.6.12-rc2 |
793 794 795 |
* shrink_dcache_sb - shrink dcache for a superblock * @sb: superblock * |
3049cfe24 fs: split __shrin... |
796 797 |
* Shrink the dcache for the specified super block. This is used to free * the dcache before unmounting a file system. |
1da177e4c Linux-2.6.12-rc2 |
798 |
*/ |
3049cfe24 fs: split __shrin... |
799 |
void shrink_dcache_sb(struct super_block *sb) |
1da177e4c Linux-2.6.12-rc2 |
800 |
{ |
3049cfe24 fs: split __shrin... |
801 |
LIST_HEAD(tmp); |
230445078 fs: dcache scale lru |
802 |
spin_lock(&dcache_lru_lock); |
3049cfe24 fs: split __shrin... |
803 804 |
while (!list_empty(&sb->s_dentry_lru)) { list_splice_init(&sb->s_dentry_lru, &tmp); |
ec33679d7 fs: use RCU in sh... |
805 |
spin_unlock(&dcache_lru_lock); |
3049cfe24 fs: split __shrin... |
806 |
shrink_dentry_list(&tmp); |
ec33679d7 fs: use RCU in sh... |
807 |
spin_lock(&dcache_lru_lock); |
3049cfe24 fs: split __shrin... |
808 |
} |
230445078 fs: dcache scale lru |
809 |
spin_unlock(&dcache_lru_lock); |
1da177e4c Linux-2.6.12-rc2 |
810 |
} |
ec4f86059 fs/dcache.c: Codi... |
811 |
EXPORT_SYMBOL(shrink_dcache_sb); |
1da177e4c Linux-2.6.12-rc2 |
812 813 |
/* |
c636ebdb1 [PATCH] VFS: Dest... |
814 815 816 817 818 819 820 821 822 |
* destroy a single subtree of dentries for unmount * - see the comments on shrink_dcache_for_umount() for a description of the * locking */ static void shrink_dcache_for_umount_subtree(struct dentry *dentry) { struct dentry *parent; BUG_ON(!IS_ROOT(dentry)); |
c636ebdb1 [PATCH] VFS: Dest... |
823 824 |
for (;;) { /* descend to the first leaf in the current subtree */ |
43c1c9cd2 VFS: Reorganise s... |
825 |
while (!list_empty(&dentry->d_subdirs)) |
c636ebdb1 [PATCH] VFS: Dest... |
826 827 |
dentry = list_entry(dentry->d_subdirs.next, struct dentry, d_u.d_child); |
c636ebdb1 [PATCH] VFS: Dest... |
828 829 830 831 832 |
/* consume the dentries from this leaf up through its parents * until we find one with children or run out altogether */ do { struct inode *inode; |
f0023bc61 vfs: add d_prune ... |
833 834 835 836 837 838 |
/* * remove the dentry from the lru, and inform * the fs that this dentry is about to be * unhashed and destroyed. */ dentry_lru_prune(dentry); |
43c1c9cd2 VFS: Reorganise s... |
839 |
__d_shrink(dentry); |
b7ab39f63 fs: dcache scale ... |
840 |
if (dentry->d_count != 0) { |
c636ebdb1 [PATCH] VFS: Dest... |
841 842 843 844 845 846 847 848 849 |
printk(KERN_ERR "BUG: Dentry %p{i=%lx,n=%s}" " still in use (%d)" " [unmount of %s %s] ", dentry, dentry->d_inode ? dentry->d_inode->i_ino : 0UL, dentry->d_name.name, |
b7ab39f63 fs: dcache scale ... |
850 |
dentry->d_count, |
c636ebdb1 [PATCH] VFS: Dest... |
851 852 853 854 |
dentry->d_sb->s_type->name, dentry->d_sb->s_id); BUG(); } |
2fd6b7f50 fs: dcache scale ... |
855 |
if (IS_ROOT(dentry)) { |
c636ebdb1 [PATCH] VFS: Dest... |
856 |
parent = NULL; |
2fd6b7f50 fs: dcache scale ... |
857 858 |
list_del(&dentry->d_u.d_child); } else { |
871c0067d [PATCH vfs-2.6 1/... |
859 |
parent = dentry->d_parent; |
b7ab39f63 fs: dcache scale ... |
860 |
parent->d_count--; |
2fd6b7f50 fs: dcache scale ... |
861 |
list_del(&dentry->d_u.d_child); |
871c0067d [PATCH vfs-2.6 1/... |
862 |
} |
c636ebdb1 [PATCH] VFS: Dest... |
863 |
|
c636ebdb1 [PATCH] VFS: Dest... |
864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 |
inode = dentry->d_inode; if (inode) { dentry->d_inode = NULL; list_del_init(&dentry->d_alias); if (dentry->d_op && dentry->d_op->d_iput) dentry->d_op->d_iput(dentry, inode); else iput(inode); } d_free(dentry); /* finished when we fall off the top of the tree, * otherwise we ascend to the parent and move to the * next sibling if there is one */ if (!parent) |
312d3ca85 fs: use percpu co... |
880 |
return; |
c636ebdb1 [PATCH] VFS: Dest... |
881 |
dentry = parent; |
c636ebdb1 [PATCH] VFS: Dest... |
882 883 884 885 886 887 888 889 890 |
} while (list_empty(&dentry->d_subdirs)); dentry = list_entry(dentry->d_subdirs.next, struct dentry, d_u.d_child); } } /* * destroy the dentries attached to a superblock on unmounting |
b5c84bf6f fs: dcache remove... |
891 |
* - we don't need to use dentry->d_lock because: |
c636ebdb1 [PATCH] VFS: Dest... |
892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 |
* - the superblock is detached from all mountings and open files, so the * dentry trees will not be rearranged by the VFS * - s_umount is write-locked, so the memory pressure shrinker will ignore * any dentries belonging to this superblock that it comes across * - the filesystem itself is no longer permitted to rearrange the dentries * in this superblock */ void shrink_dcache_for_umount(struct super_block *sb) { struct dentry *dentry; if (down_read_trylock(&sb->s_umount)) BUG(); dentry = sb->s_root; sb->s_root = NULL; |
b7ab39f63 fs: dcache scale ... |
908 |
dentry->d_count--; |
c636ebdb1 [PATCH] VFS: Dest... |
909 |
shrink_dcache_for_umount_subtree(dentry); |
ceb5bdc2d fs: dcache per-bu... |
910 911 |
while (!hlist_bl_empty(&sb->s_anon)) { dentry = hlist_bl_entry(hlist_bl_first(&sb->s_anon), struct dentry, d_hash); |
c636ebdb1 [PATCH] VFS: Dest... |
912 913 914 915 916 |
shrink_dcache_for_umount_subtree(dentry); } } /* |
c826cb7df dcache.c: create ... |
917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 |
* This tries to ascend one level of parenthood, but * we can race with renaming, so we need to re-check * the parenthood after dropping the lock and check * that the sequence number still matches. */ static struct dentry *try_to_ascend(struct dentry *old, int locked, unsigned seq) { struct dentry *new = old->d_parent; rcu_read_lock(); spin_unlock(&old->d_lock); spin_lock(&new->d_lock); /* * might go back up the wrong parent if we have had a rename * or deletion */ if (new != old->d_parent || |
c83ce989c VFS: Fix the nfs ... |
935 |
(old->d_flags & DCACHE_DISCONNECTED) || |
c826cb7df dcache.c: create ... |
936 937 938 939 940 941 942 943 944 945 |
(!locked && read_seqretry(&rename_lock, seq))) { spin_unlock(&new->d_lock); new = NULL; } rcu_read_unlock(); return new; } /* |
1da177e4c Linux-2.6.12-rc2 |
946 947 948 949 950 951 952 953 954 955 956 957 |
* Search for at least 1 mount point in the dentry's subdirs. * We descend to the next level whenever the d_subdirs * list is non-empty and continue searching. */ /** * have_submounts - check for mounts over a dentry * @parent: dentry to check. * * Return true if the parent or its subdirectories contain * a mount point */ |
1da177e4c Linux-2.6.12-rc2 |
958 959 |
int have_submounts(struct dentry *parent) { |
949854d02 fs: Use rename lo... |
960 |
struct dentry *this_parent; |
1da177e4c Linux-2.6.12-rc2 |
961 |
struct list_head *next; |
949854d02 fs: Use rename lo... |
962 |
unsigned seq; |
58db63d08 fs: dcache avoid ... |
963 |
int locked = 0; |
949854d02 fs: Use rename lo... |
964 |
|
949854d02 fs: Use rename lo... |
965 |
seq = read_seqbegin(&rename_lock); |
58db63d08 fs: dcache avoid ... |
966 967 |
again: this_parent = parent; |
1da177e4c Linux-2.6.12-rc2 |
968 |
|
1da177e4c Linux-2.6.12-rc2 |
969 970 |
if (d_mountpoint(parent)) goto positive; |
2fd6b7f50 fs: dcache scale ... |
971 |
spin_lock(&this_parent->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
972 973 974 975 976 |
repeat: next = this_parent->d_subdirs.next; resume: while (next != &this_parent->d_subdirs) { struct list_head *tmp = next; |
5160ee6fc [PATCH] shrink de... |
977 |
struct dentry *dentry = list_entry(tmp, struct dentry, d_u.d_child); |
1da177e4c Linux-2.6.12-rc2 |
978 |
next = tmp->next; |
2fd6b7f50 fs: dcache scale ... |
979 980 |
spin_lock_nested(&dentry->d_lock, DENTRY_D_LOCK_NESTED); |
1da177e4c Linux-2.6.12-rc2 |
981 |
/* Have we found a mount point ? */ |
2fd6b7f50 fs: dcache scale ... |
982 983 984 |
if (d_mountpoint(dentry)) { spin_unlock(&dentry->d_lock); spin_unlock(&this_parent->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
985 |
goto positive; |
2fd6b7f50 fs: dcache scale ... |
986 |
} |
1da177e4c Linux-2.6.12-rc2 |
987 |
if (!list_empty(&dentry->d_subdirs)) { |
2fd6b7f50 fs: dcache scale ... |
988 989 |
spin_unlock(&this_parent->d_lock); spin_release(&dentry->d_lock.dep_map, 1, _RET_IP_); |
1da177e4c Linux-2.6.12-rc2 |
990 |
this_parent = dentry; |
2fd6b7f50 fs: dcache scale ... |
991 |
spin_acquire(&this_parent->d_lock.dep_map, 0, 1, _RET_IP_); |
1da177e4c Linux-2.6.12-rc2 |
992 993 |
goto repeat; } |
2fd6b7f50 fs: dcache scale ... |
994 |
spin_unlock(&dentry->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
995 996 997 998 999 |
} /* * All done at this level ... ascend and resume the search. */ if (this_parent != parent) { |
c826cb7df dcache.c: create ... |
1000 1001 1002 |
struct dentry *child = this_parent; this_parent = try_to_ascend(this_parent, locked, seq); if (!this_parent) |
949854d02 fs: Use rename lo... |
1003 |
goto rename_retry; |
949854d02 fs: Use rename lo... |
1004 |
next = child->d_u.d_child.next; |
1da177e4c Linux-2.6.12-rc2 |
1005 1006 |
goto resume; } |
2fd6b7f50 fs: dcache scale ... |
1007 |
spin_unlock(&this_parent->d_lock); |
58db63d08 fs: dcache avoid ... |
1008 |
if (!locked && read_seqretry(&rename_lock, seq)) |
949854d02 fs: Use rename lo... |
1009 |
goto rename_retry; |
58db63d08 fs: dcache avoid ... |
1010 1011 |
if (locked) write_sequnlock(&rename_lock); |
1da177e4c Linux-2.6.12-rc2 |
1012 1013 |
return 0; /* No mount points found in tree */ positive: |
58db63d08 fs: dcache avoid ... |
1014 |
if (!locked && read_seqretry(&rename_lock, seq)) |
949854d02 fs: Use rename lo... |
1015 |
goto rename_retry; |
58db63d08 fs: dcache avoid ... |
1016 1017 |
if (locked) write_sequnlock(&rename_lock); |
1da177e4c Linux-2.6.12-rc2 |
1018 |
return 1; |
58db63d08 fs: dcache avoid ... |
1019 1020 1021 1022 1023 |
rename_retry: locked = 1; write_seqlock(&rename_lock); goto again; |
1da177e4c Linux-2.6.12-rc2 |
1024 |
} |
ec4f86059 fs/dcache.c: Codi... |
1025 |
EXPORT_SYMBOL(have_submounts); |
1da177e4c Linux-2.6.12-rc2 |
1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 |
/* * Search the dentry child list for the specified parent, * and move any unused dentries to the end of the unused * list for prune_dcache(). We descend to the next level * whenever the d_subdirs list is non-empty and continue * searching. * * It returns zero iff there are no unused children, * otherwise it returns the number of children moved to * the end of the unused list. This may not be the total * number of unused children, because select_parent can * drop the lock and return early due to latency * constraints. */ |
b48f03b31 dcache: use a dis... |
1041 |
static int select_parent(struct dentry *parent, struct list_head *dispose) |
1da177e4c Linux-2.6.12-rc2 |
1042 |
{ |
949854d02 fs: Use rename lo... |
1043 |
struct dentry *this_parent; |
1da177e4c Linux-2.6.12-rc2 |
1044 |
struct list_head *next; |
949854d02 fs: Use rename lo... |
1045 |
unsigned seq; |
1da177e4c Linux-2.6.12-rc2 |
1046 |
int found = 0; |
58db63d08 fs: dcache avoid ... |
1047 |
int locked = 0; |
1da177e4c Linux-2.6.12-rc2 |
1048 |
|
949854d02 fs: Use rename lo... |
1049 |
seq = read_seqbegin(&rename_lock); |
58db63d08 fs: dcache avoid ... |
1050 1051 |
again: this_parent = parent; |
2fd6b7f50 fs: dcache scale ... |
1052 |
spin_lock(&this_parent->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
1053 1054 1055 1056 1057 |
repeat: next = this_parent->d_subdirs.next; resume: while (next != &this_parent->d_subdirs) { struct list_head *tmp = next; |
5160ee6fc [PATCH] shrink de... |
1058 |
struct dentry *dentry = list_entry(tmp, struct dentry, d_u.d_child); |
1da177e4c Linux-2.6.12-rc2 |
1059 |
next = tmp->next; |
2fd6b7f50 fs: dcache scale ... |
1060 |
spin_lock_nested(&dentry->d_lock, DENTRY_D_LOCK_NESTED); |
230445078 fs: dcache scale lru |
1061 |
|
b48f03b31 dcache: use a dis... |
1062 1063 |
/* * move only zero ref count dentries to the dispose list. |
eaf5f9073 fix shrink_dcache... |
1064 1065 1066 1067 1068 |
* * Those which are presently on the shrink list, being processed * by shrink_dentry_list(), shouldn't be moved. Otherwise the * loop in shrink_dcache_parent() might not make any progress * and loop forever. |
1da177e4c Linux-2.6.12-rc2 |
1069 |
*/ |
eaf5f9073 fix shrink_dcache... |
1070 1071 1072 |
if (dentry->d_count) { dentry_lru_del(dentry); } else if (!(dentry->d_flags & DCACHE_SHRINK_LIST)) { |
b48f03b31 dcache: use a dis... |
1073 |
dentry_lru_move_list(dentry, dispose); |
eaf5f9073 fix shrink_dcache... |
1074 |
dentry->d_flags |= DCACHE_SHRINK_LIST; |
1da177e4c Linux-2.6.12-rc2 |
1075 1076 |
found++; } |
1da177e4c Linux-2.6.12-rc2 |
1077 1078 1079 1080 1081 |
/* * We can return to the caller if we have found some (this * ensures forward progress). We'll be coming back to find * the rest. */ |
2fd6b7f50 fs: dcache scale ... |
1082 1083 |
if (found && need_resched()) { spin_unlock(&dentry->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
1084 |
goto out; |
2fd6b7f50 fs: dcache scale ... |
1085 |
} |
1da177e4c Linux-2.6.12-rc2 |
1086 1087 1088 1089 1090 |
/* * Descend a level if the d_subdirs list is non-empty. */ if (!list_empty(&dentry->d_subdirs)) { |
2fd6b7f50 fs: dcache scale ... |
1091 1092 |
spin_unlock(&this_parent->d_lock); spin_release(&dentry->d_lock.dep_map, 1, _RET_IP_); |
1da177e4c Linux-2.6.12-rc2 |
1093 |
this_parent = dentry; |
2fd6b7f50 fs: dcache scale ... |
1094 |
spin_acquire(&this_parent->d_lock.dep_map, 0, 1, _RET_IP_); |
1da177e4c Linux-2.6.12-rc2 |
1095 1096 |
goto repeat; } |
2fd6b7f50 fs: dcache scale ... |
1097 1098 |
spin_unlock(&dentry->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
1099 1100 1101 1102 1103 |
} /* * All done at this level ... ascend and resume the search. */ if (this_parent != parent) { |
c826cb7df dcache.c: create ... |
1104 1105 1106 |
struct dentry *child = this_parent; this_parent = try_to_ascend(this_parent, locked, seq); if (!this_parent) |
949854d02 fs: Use rename lo... |
1107 |
goto rename_retry; |
949854d02 fs: Use rename lo... |
1108 |
next = child->d_u.d_child.next; |
1da177e4c Linux-2.6.12-rc2 |
1109 1110 1111 |
goto resume; } out: |
2fd6b7f50 fs: dcache scale ... |
1112 |
spin_unlock(&this_parent->d_lock); |
58db63d08 fs: dcache avoid ... |
1113 |
if (!locked && read_seqretry(&rename_lock, seq)) |
949854d02 fs: Use rename lo... |
1114 |
goto rename_retry; |
58db63d08 fs: dcache avoid ... |
1115 1116 |
if (locked) write_sequnlock(&rename_lock); |
1da177e4c Linux-2.6.12-rc2 |
1117 |
return found; |
58db63d08 fs: dcache avoid ... |
1118 1119 1120 1121 1122 1123 1124 |
rename_retry: if (found) return found; locked = 1; write_seqlock(&rename_lock); goto again; |
1da177e4c Linux-2.6.12-rc2 |
1125 1126 1127 1128 1129 1130 1131 1132 |
} /** * shrink_dcache_parent - prune dcache * @parent: parent of entries to prune * * Prune the dcache to remove unused children of the parent dentry. */ |
1da177e4c Linux-2.6.12-rc2 |
1133 1134 |
void shrink_dcache_parent(struct dentry * parent) { |
b48f03b31 dcache: use a dis... |
1135 |
LIST_HEAD(dispose); |
1da177e4c Linux-2.6.12-rc2 |
1136 |
int found; |
b48f03b31 dcache: use a dis... |
1137 1138 |
while ((found = select_parent(parent, &dispose)) != 0) shrink_dentry_list(&dispose); |
1da177e4c Linux-2.6.12-rc2 |
1139 |
} |
ec4f86059 fs/dcache.c: Codi... |
1140 |
EXPORT_SYMBOL(shrink_dcache_parent); |
1da177e4c Linux-2.6.12-rc2 |
1141 |
|
1da177e4c Linux-2.6.12-rc2 |
1142 |
/** |
a4464dbc0 Make ->d_sb assig... |
1143 1144 |
* __d_alloc - allocate a dcache entry * @sb: filesystem it will belong to |
1da177e4c Linux-2.6.12-rc2 |
1145 1146 1147 1148 1149 1150 1151 |
* @name: qstr of the name * * Allocates a dentry. It returns %NULL if there is insufficient memory * available. On a success the dentry is returned. The name passed in is * copied and the copy passed in may be reused after this call. */ |
a4464dbc0 Make ->d_sb assig... |
1152 |
struct dentry *__d_alloc(struct super_block *sb, const struct qstr *name) |
1da177e4c Linux-2.6.12-rc2 |
1153 1154 1155 |
{ struct dentry *dentry; char *dname; |
e12ba74d8 Group short-lived... |
1156 |
dentry = kmem_cache_alloc(dentry_cache, GFP_KERNEL); |
1da177e4c Linux-2.6.12-rc2 |
1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 |
if (!dentry) return NULL; if (name->len > DNAME_INLINE_LEN-1) { dname = kmalloc(name->len + 1, GFP_KERNEL); if (!dname) { kmem_cache_free(dentry_cache, dentry); return NULL; } } else { dname = dentry->d_iname; } dentry->d_name.name = dname; dentry->d_name.len = name->len; dentry->d_name.hash = name->hash; memcpy(dname, name->name, name->len); dname[name->len] = 0; |
b7ab39f63 fs: dcache scale ... |
1175 |
dentry->d_count = 1; |
dea3667bc vfs: get rid of i... |
1176 |
dentry->d_flags = 0; |
1da177e4c Linux-2.6.12-rc2 |
1177 |
spin_lock_init(&dentry->d_lock); |
31e6b01f4 fs: rcu-walk for ... |
1178 |
seqcount_init(&dentry->d_seq); |
1da177e4c Linux-2.6.12-rc2 |
1179 |
dentry->d_inode = NULL; |
a4464dbc0 Make ->d_sb assig... |
1180 1181 |
dentry->d_parent = dentry; dentry->d_sb = sb; |
1da177e4c Linux-2.6.12-rc2 |
1182 1183 |
dentry->d_op = NULL; dentry->d_fsdata = NULL; |
ceb5bdc2d fs: dcache per-bu... |
1184 |
INIT_HLIST_BL_NODE(&dentry->d_hash); |
1da177e4c Linux-2.6.12-rc2 |
1185 1186 1187 |
INIT_LIST_HEAD(&dentry->d_lru); INIT_LIST_HEAD(&dentry->d_subdirs); INIT_LIST_HEAD(&dentry->d_alias); |
2fd6b7f50 fs: dcache scale ... |
1188 |
INIT_LIST_HEAD(&dentry->d_u.d_child); |
a4464dbc0 Make ->d_sb assig... |
1189 |
d_set_d_op(dentry, dentry->d_sb->s_d_op); |
1da177e4c Linux-2.6.12-rc2 |
1190 |
|
3e880fb5e fs: use fast coun... |
1191 |
this_cpu_inc(nr_dentry); |
312d3ca85 fs: use percpu co... |
1192 |
|
1da177e4c Linux-2.6.12-rc2 |
1193 1194 |
return dentry; } |
a4464dbc0 Make ->d_sb assig... |
1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 |
/** * d_alloc - allocate a dcache entry * @parent: parent of entry to allocate * @name: qstr of the name * * Allocates a dentry. It returns %NULL if there is insufficient memory * available. On a success the dentry is returned. The name passed in is * copied and the copy passed in may be reused after this call. */ struct dentry *d_alloc(struct dentry * parent, const struct qstr *name) { struct dentry *dentry = __d_alloc(parent->d_sb, name); if (!dentry) return NULL; spin_lock(&parent->d_lock); /* * don't need child lock because it is not subject * to concurrency here */ __dget_dlock(parent); dentry->d_parent = parent; list_add(&dentry->d_u.d_child, &parent->d_subdirs); spin_unlock(&parent->d_lock); return dentry; } |
ec4f86059 fs/dcache.c: Codi... |
1223 |
EXPORT_SYMBOL(d_alloc); |
1da177e4c Linux-2.6.12-rc2 |
1224 |
|
4b936885a fs: improve scala... |
1225 1226 |
struct dentry *d_alloc_pseudo(struct super_block *sb, const struct qstr *name) { |
a4464dbc0 Make ->d_sb assig... |
1227 1228 |
struct dentry *dentry = __d_alloc(sb, name); if (dentry) |
4b936885a fs: improve scala... |
1229 |
dentry->d_flags |= DCACHE_DISCONNECTED; |
4b936885a fs: improve scala... |
1230 1231 1232 |
return dentry; } EXPORT_SYMBOL(d_alloc_pseudo); |
1da177e4c Linux-2.6.12-rc2 |
1233 1234 1235 1236 1237 1238 1239 1240 1241 |
struct dentry *d_alloc_name(struct dentry *parent, const char *name) { struct qstr q; q.name = name; q.len = strlen(name); q.hash = full_name_hash(q.name, q.len); return d_alloc(parent, &q); } |
ef26ca97e libfs: move EXPOR... |
1242 |
EXPORT_SYMBOL(d_alloc_name); |
1da177e4c Linux-2.6.12-rc2 |
1243 |
|
fb045adb9 fs: dcache reduce... |
1244 1245 |
void d_set_d_op(struct dentry *dentry, const struct dentry_operations *op) { |
6f7f7caab Turn d_set_d_op()... |
1246 1247 |
WARN_ON_ONCE(dentry->d_op); WARN_ON_ONCE(dentry->d_flags & (DCACHE_OP_HASH | |
fb045adb9 fs: dcache reduce... |
1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 |
DCACHE_OP_COMPARE | DCACHE_OP_REVALIDATE | DCACHE_OP_DELETE )); dentry->d_op = op; if (!op) return; if (op->d_hash) dentry->d_flags |= DCACHE_OP_HASH; if (op->d_compare) dentry->d_flags |= DCACHE_OP_COMPARE; if (op->d_revalidate) dentry->d_flags |= DCACHE_OP_REVALIDATE; if (op->d_delete) dentry->d_flags |= DCACHE_OP_DELETE; |
f0023bc61 vfs: add d_prune ... |
1262 1263 |
if (op->d_prune) dentry->d_flags |= DCACHE_OP_PRUNE; |
fb045adb9 fs: dcache reduce... |
1264 1265 1266 |
} EXPORT_SYMBOL(d_set_d_op); |
360da9002 [PATCH vfs-2.6 3/... |
1267 1268 |
static void __d_instantiate(struct dentry *dentry, struct inode *inode) { |
b23fb0a60 fs: scale inode a... |
1269 |
spin_lock(&dentry->d_lock); |
9875cf806 Add a dentry op t... |
1270 1271 1272 |
if (inode) { if (unlikely(IS_AUTOMOUNT(inode))) dentry->d_flags |= DCACHE_NEED_AUTOMOUNT; |
360da9002 [PATCH vfs-2.6 3/... |
1273 |
list_add(&dentry->d_alias, &inode->i_dentry); |
9875cf806 Add a dentry op t... |
1274 |
} |
360da9002 [PATCH vfs-2.6 3/... |
1275 |
dentry->d_inode = inode; |
31e6b01f4 fs: rcu-walk for ... |
1276 |
dentry_rcuwalk_barrier(dentry); |
b23fb0a60 fs: scale inode a... |
1277 |
spin_unlock(&dentry->d_lock); |
360da9002 [PATCH vfs-2.6 3/... |
1278 1279 |
fsnotify_d_instantiate(dentry, inode); } |
1da177e4c Linux-2.6.12-rc2 |
1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 |
/** * d_instantiate - fill in inode information for a dentry * @entry: dentry to complete * @inode: inode to attach to this dentry * * Fill in inode information in the entry. * * This turns negative dentries into productive full members * of society. * * NOTE! This assumes that the inode count has been incremented * (or otherwise set) by the caller to indicate that it is now * in use by the dcache. */ void d_instantiate(struct dentry *entry, struct inode * inode) { |
28133c7b2 BUG_ON() Conversi... |
1297 |
BUG_ON(!list_empty(&entry->d_alias)); |
873feea09 fs: dcache per-in... |
1298 1299 |
if (inode) spin_lock(&inode->i_lock); |
360da9002 [PATCH vfs-2.6 3/... |
1300 |
__d_instantiate(entry, inode); |
873feea09 fs: dcache per-in... |
1301 1302 |
if (inode) spin_unlock(&inode->i_lock); |
1da177e4c Linux-2.6.12-rc2 |
1303 1304 |
security_d_instantiate(entry, inode); } |
ec4f86059 fs/dcache.c: Codi... |
1305 |
EXPORT_SYMBOL(d_instantiate); |
1da177e4c Linux-2.6.12-rc2 |
1306 1307 1308 1309 1310 1311 1312 1313 |
/** * d_instantiate_unique - instantiate a non-aliased dentry * @entry: dentry to instantiate * @inode: inode to attach to this dentry * * Fill in inode information in the entry. On success, it returns NULL. * If an unhashed alias of "entry" already exists, then we return the |
e866cfa93 [PATCH] d_instant... |
1314 |
* aliased dentry instead and drop one reference to inode. |
1da177e4c Linux-2.6.12-rc2 |
1315 1316 1317 |
* * Note that in order to avoid conflicts with rename() etc, the caller * had better be holding the parent directory semaphore. |
e866cfa93 [PATCH] d_instant... |
1318 1319 1320 1321 |
* * This also assumes that the inode count has been incremented * (or otherwise set) by the caller to indicate that it is now * in use by the dcache. |
1da177e4c Linux-2.6.12-rc2 |
1322 |
*/ |
770bfad84 NFS: Add dentry m... |
1323 1324 |
static struct dentry *__d_instantiate_unique(struct dentry *entry, struct inode *inode) |
1da177e4c Linux-2.6.12-rc2 |
1325 1326 1327 1328 1329 |
{ struct dentry *alias; int len = entry->d_name.len; const char *name = entry->d_name.name; unsigned int hash = entry->d_name.hash; |
770bfad84 NFS: Add dentry m... |
1330 |
if (!inode) { |
360da9002 [PATCH vfs-2.6 3/... |
1331 |
__d_instantiate(entry, NULL); |
770bfad84 NFS: Add dentry m... |
1332 1333 |
return NULL; } |
1da177e4c Linux-2.6.12-rc2 |
1334 1335 |
list_for_each_entry(alias, &inode->i_dentry, d_alias) { struct qstr *qstr = &alias->d_name; |
9abca3608 fs: increase d_na... |
1336 1337 1338 1339 1340 |
/* * Don't need alias->d_lock here, because aliases with * d_parent == entry->d_parent are not subject to name or * parent changes, because the parent inode i_mutex is held. */ |
1da177e4c Linux-2.6.12-rc2 |
1341 1342 1343 1344 |
if (qstr->hash != hash) continue; if (alias->d_parent != entry->d_parent) continue; |
9d55c369b fs: implement fas... |
1345 |
if (dentry_cmp(qstr->name, qstr->len, name, len)) |
1da177e4c Linux-2.6.12-rc2 |
1346 |
continue; |
dc0474be3 fs: dcache ration... |
1347 |
__dget(alias); |
1da177e4c Linux-2.6.12-rc2 |
1348 1349 |
return alias; } |
770bfad84 NFS: Add dentry m... |
1350 |
|
360da9002 [PATCH vfs-2.6 3/... |
1351 |
__d_instantiate(entry, inode); |
1da177e4c Linux-2.6.12-rc2 |
1352 1353 |
return NULL; } |
770bfad84 NFS: Add dentry m... |
1354 1355 1356 1357 1358 1359 |
struct dentry *d_instantiate_unique(struct dentry *entry, struct inode *inode) { struct dentry *result; BUG_ON(!list_empty(&entry->d_alias)); |
873feea09 fs: dcache per-in... |
1360 1361 |
if (inode) spin_lock(&inode->i_lock); |
770bfad84 NFS: Add dentry m... |
1362 |
result = __d_instantiate_unique(entry, inode); |
873feea09 fs: dcache per-in... |
1363 1364 |
if (inode) spin_unlock(&inode->i_lock); |
770bfad84 NFS: Add dentry m... |
1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 |
if (!result) { security_d_instantiate(entry, inode); return NULL; } BUG_ON(!d_unhashed(result)); iput(inode); return result; } |
1da177e4c Linux-2.6.12-rc2 |
1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 |
EXPORT_SYMBOL(d_instantiate_unique); /** * d_alloc_root - allocate root dentry * @root_inode: inode to allocate the root for * * Allocate a root ("/") dentry for the inode given. The inode is * instantiated and returned. %NULL is returned if there is insufficient * memory or the inode passed is %NULL. */ struct dentry * d_alloc_root(struct inode * root_inode) { struct dentry *res = NULL; if (root_inode) { static const struct qstr name = { .name = "/", .len = 1 }; |
a4464dbc0 Make ->d_sb assig... |
1392 1393 |
res = __d_alloc(root_inode->i_sb, &name); if (res) |
1da177e4c Linux-2.6.12-rc2 |
1394 |
d_instantiate(res, root_inode); |
1da177e4c Linux-2.6.12-rc2 |
1395 1396 1397 |
} return res; } |
ec4f86059 fs/dcache.c: Codi... |
1398 |
EXPORT_SYMBOL(d_alloc_root); |
1da177e4c Linux-2.6.12-rc2 |
1399 |
|
adc0e91ab vfs: new helper -... |
1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 |
struct dentry *d_make_root(struct inode *root_inode) { struct dentry *res = NULL; if (root_inode) { static const struct qstr name = { .name = "/", .len = 1 }; res = __d_alloc(root_inode->i_sb, &name); if (res) d_instantiate(res, root_inode); else iput(root_inode); } return res; } EXPORT_SYMBOL(d_make_root); |
d891eedbc fs/dcache: allow ... |
1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 |
static struct dentry * __d_find_any_alias(struct inode *inode) { struct dentry *alias; if (list_empty(&inode->i_dentry)) return NULL; alias = list_first_entry(&inode->i_dentry, struct dentry, d_alias); __dget(alias); return alias; } |
46f72b349 vfs: export symbo... |
1426 1427 1428 1429 1430 1431 1432 1433 |
/** * d_find_any_alias - find any alias for a given inode * @inode: inode to find an alias for * * If any aliases exist for the given inode, take and return a * reference for one of them. If no aliases exist, return %NULL. */ struct dentry *d_find_any_alias(struct inode *inode) |
d891eedbc fs/dcache: allow ... |
1434 1435 1436 1437 1438 1439 1440 1441 |
{ struct dentry *de; spin_lock(&inode->i_lock); de = __d_find_any_alias(inode); spin_unlock(&inode->i_lock); return de; } |
46f72b349 vfs: export symbo... |
1442 |
EXPORT_SYMBOL(d_find_any_alias); |
d891eedbc fs/dcache: allow ... |
1443 |
|
1da177e4c Linux-2.6.12-rc2 |
1444 |
/** |
4ea3ada29 [PATCH] new helpe... |
1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 |
* d_obtain_alias - find or allocate a dentry for a given inode * @inode: inode to allocate the dentry for * * Obtain a dentry for an inode resulting from NFS filehandle conversion or * similar open by handle operations. The returned dentry may be anonymous, * or may have a full name (if the inode was already in the cache). * * When called on a directory inode, we must ensure that the inode only ever * has one dentry. If a dentry is found, that is returned instead of * allocating a new one. * * On successful return, the reference to the inode has been transferred |
440037287 [PATCH] switch al... |
1457 1458 1459 1460 |
* to the dentry. In case of an error the reference on the inode is released. * To make it easier to use in export operations a %NULL or IS_ERR inode may * be passed in and will be the error will be propagate to the return value, * with a %NULL @inode replaced by ERR_PTR(-ESTALE). |
4ea3ada29 [PATCH] new helpe... |
1461 1462 1463 |
*/ struct dentry *d_obtain_alias(struct inode *inode) { |
9308a6128 [PATCH] kill d_al... |
1464 1465 1466 |
static const struct qstr anonstring = { .name = "" }; struct dentry *tmp; struct dentry *res; |
4ea3ada29 [PATCH] new helpe... |
1467 1468 |
if (!inode) |
440037287 [PATCH] switch al... |
1469 |
return ERR_PTR(-ESTALE); |
4ea3ada29 [PATCH] new helpe... |
1470 1471 |
if (IS_ERR(inode)) return ERR_CAST(inode); |
d891eedbc fs/dcache: allow ... |
1472 |
res = d_find_any_alias(inode); |
9308a6128 [PATCH] kill d_al... |
1473 1474 |
if (res) goto out_iput; |
a4464dbc0 Make ->d_sb assig... |
1475 |
tmp = __d_alloc(inode->i_sb, &anonstring); |
9308a6128 [PATCH] kill d_al... |
1476 1477 1478 |
if (!tmp) { res = ERR_PTR(-ENOMEM); goto out_iput; |
4ea3ada29 [PATCH] new helpe... |
1479 |
} |
b5c84bf6f fs: dcache remove... |
1480 |
|
873feea09 fs: dcache per-in... |
1481 |
spin_lock(&inode->i_lock); |
d891eedbc fs/dcache: allow ... |
1482 |
res = __d_find_any_alias(inode); |
9308a6128 [PATCH] kill d_al... |
1483 |
if (res) { |
873feea09 fs: dcache per-in... |
1484 |
spin_unlock(&inode->i_lock); |
9308a6128 [PATCH] kill d_al... |
1485 1486 1487 1488 1489 1490 |
dput(tmp); goto out_iput; } /* attach a disconnected dentry */ spin_lock(&tmp->d_lock); |
9308a6128 [PATCH] kill d_al... |
1491 1492 |
tmp->d_inode = inode; tmp->d_flags |= DCACHE_DISCONNECTED; |
9308a6128 [PATCH] kill d_al... |
1493 |
list_add(&tmp->d_alias, &inode->i_dentry); |
1879fd6a2 add hlist_bl_lock... |
1494 |
hlist_bl_lock(&tmp->d_sb->s_anon); |
ceb5bdc2d fs: dcache per-bu... |
1495 |
hlist_bl_add_head(&tmp->d_hash, &tmp->d_sb->s_anon); |
1879fd6a2 add hlist_bl_lock... |
1496 |
hlist_bl_unlock(&tmp->d_sb->s_anon); |
9308a6128 [PATCH] kill d_al... |
1497 |
spin_unlock(&tmp->d_lock); |
873feea09 fs: dcache per-in... |
1498 |
spin_unlock(&inode->i_lock); |
24ff6663c fs: call security... |
1499 |
security_d_instantiate(tmp, inode); |
9308a6128 [PATCH] kill d_al... |
1500 |
|
9308a6128 [PATCH] kill d_al... |
1501 1502 1503 |
return tmp; out_iput: |
24ff6663c fs: call security... |
1504 1505 |
if (res && !IS_ERR(res)) security_d_instantiate(res, inode); |
9308a6128 [PATCH] kill d_al... |
1506 1507 |
iput(inode); return res; |
4ea3ada29 [PATCH] new helpe... |
1508 |
} |
adc487204 EXPORT_SYMBOL(d_o... |
1509 |
EXPORT_SYMBOL(d_obtain_alias); |
1da177e4c Linux-2.6.12-rc2 |
1510 1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 |
/** * d_splice_alias - splice a disconnected dentry into the tree if one exists * @inode: the inode which may have a disconnected dentry * @dentry: a negative dentry which we want to point to the inode. * * If inode is a directory and has a 'disconnected' dentry (i.e. IS_ROOT and * DCACHE_DISCONNECTED), then d_move that in place of the given dentry * and return it, else simply d_add the inode to the dentry and return NULL. * * This is needed in the lookup routine of any filesystem that is exportable * (via knfsd) so that we can build dcache paths to directories effectively. * * If a dentry was found and moved, then it is returned. Otherwise NULL * is returned. This matches the expected return value of ->lookup. * */ struct dentry *d_splice_alias(struct inode *inode, struct dentry *dentry) { struct dentry *new = NULL; |
a9049376e make d_splice_ali... |
1530 1531 |
if (IS_ERR(inode)) return ERR_CAST(inode); |
21c0d8fdd [PATCH] knfsd: cl... |
1532 |
if (inode && S_ISDIR(inode->i_mode)) { |
873feea09 fs: dcache per-in... |
1533 |
spin_lock(&inode->i_lock); |
1da177e4c Linux-2.6.12-rc2 |
1534 1535 1536 |
new = __d_find_alias(inode, 1); if (new) { BUG_ON(!(new->d_flags & DCACHE_DISCONNECTED)); |
873feea09 fs: dcache per-in... |
1537 |
spin_unlock(&inode->i_lock); |
1da177e4c Linux-2.6.12-rc2 |
1538 |
security_d_instantiate(new, inode); |
1da177e4c Linux-2.6.12-rc2 |
1539 1540 1541 |
d_move(new, dentry); iput(inode); } else { |
873feea09 fs: dcache per-in... |
1542 |
/* already taking inode->i_lock, so d_add() by hand */ |
360da9002 [PATCH vfs-2.6 3/... |
1543 |
__d_instantiate(dentry, inode); |
873feea09 fs: dcache per-in... |
1544 |
spin_unlock(&inode->i_lock); |
1da177e4c Linux-2.6.12-rc2 |
1545 1546 1547 1548 1549 1550 1551 |
security_d_instantiate(dentry, inode); d_rehash(dentry); } } else d_add(dentry, inode); return new; } |
ec4f86059 fs/dcache.c: Codi... |
1552 |
EXPORT_SYMBOL(d_splice_alias); |
1da177e4c Linux-2.6.12-rc2 |
1553 |
|
9403540c0 dcache: Add case-... |
1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 |
/** * d_add_ci - lookup or allocate new dentry with case-exact name * @inode: the inode case-insensitive lookup has found * @dentry: the negative dentry that was passed to the parent's lookup func * @name: the case-exact name to be associated with the returned dentry * * This is to avoid filling the dcache with case-insensitive names to the * same inode, only the actual correct case is stored in the dcache for * case-insensitive filesystems. * * For a case-insensitive lookup match and if the the case-exact dentry * already exists in in the dcache, use it and return it. * * If no entry exists with the exact case name, allocate new dentry with * the exact case, and return the spliced entry. */ |
e45b590b9 [PATCH] change d_... |
1570 |
struct dentry *d_add_ci(struct dentry *dentry, struct inode *inode, |
9403540c0 dcache: Add case-... |
1571 1572 1573 1574 1575 |
struct qstr *name) { int error; struct dentry *found; struct dentry *new; |
b6520c819 cleanup d_add_ci |
1576 1577 1578 1579 |
/* * First check if a dentry matching the name already exists, * if not go ahead and create it now. */ |
9403540c0 dcache: Add case-... |
1580 |
found = d_hash_and_lookup(dentry->d_parent, name); |
9403540c0 dcache: Add case-... |
1581 1582 1583 1584 1585 1586 |
if (!found) { new = d_alloc(dentry->d_parent, name); if (!new) { error = -ENOMEM; goto err_out; } |
b6520c819 cleanup d_add_ci |
1587 |
|
9403540c0 dcache: Add case-... |
1588 1589 1590 1591 1592 1593 1594 |
found = d_splice_alias(inode, new); if (found) { dput(new); return found; } return new; } |
b6520c819 cleanup d_add_ci |
1595 1596 1597 1598 1599 1600 1601 |
/* * If a matching dentry exists, and it's not negative use it. * * Decrement the reference count to balance the iget() done * earlier on. */ |
9403540c0 dcache: Add case-... |
1602 1603 1604 1605 1606 1607 |
if (found->d_inode) { if (unlikely(found->d_inode != inode)) { /* This can't happen because bad inodes are unhashed. */ BUG_ON(!is_bad_inode(inode)); BUG_ON(!is_bad_inode(found->d_inode)); } |
9403540c0 dcache: Add case-... |
1608 1609 1610 |
iput(inode); return found; } |
b6520c819 cleanup d_add_ci |
1611 |
|
9403540c0 dcache: Add case-... |
1612 |
/* |
44396f4b5 fs: add a DCACHE_... |
1613 1614 |
* We are going to instantiate this dentry, unhash it and clear the * lookup flag so we can do that. |
9403540c0 dcache: Add case-... |
1615 |
*/ |
44396f4b5 fs: add a DCACHE_... |
1616 1617 |
if (unlikely(d_need_lookup(found))) d_clear_need_lookup(found); |
b6520c819 cleanup d_add_ci |
1618 |
|
9403540c0 dcache: Add case-... |
1619 |
/* |
9403540c0 dcache: Add case-... |
1620 |
* Negative dentry: instantiate it unless the inode is a directory and |
b6520c819 cleanup d_add_ci |
1621 |
* already has a dentry. |
9403540c0 dcache: Add case-... |
1622 |
*/ |
4513d899c switch d_add_ci()... |
1623 1624 1625 1626 |
new = d_splice_alias(inode, found); if (new) { dput(found); found = new; |
9403540c0 dcache: Add case-... |
1627 |
} |
4513d899c switch d_add_ci()... |
1628 |
return found; |
9403540c0 dcache: Add case-... |
1629 1630 1631 1632 1633 |
err_out: iput(inode); return ERR_PTR(error); } |
ec4f86059 fs/dcache.c: Codi... |
1634 |
EXPORT_SYMBOL(d_add_ci); |
1da177e4c Linux-2.6.12-rc2 |
1635 1636 |
/** |
31e6b01f4 fs: rcu-walk for ... |
1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664 1665 1666 1667 1668 |
* __d_lookup_rcu - search for a dentry (racy, store-free) * @parent: parent dentry * @name: qstr of name we wish to find * @seq: returns d_seq value at the point where the dentry was found * @inode: returns dentry->d_inode when the inode was found valid. * Returns: dentry, or NULL * * __d_lookup_rcu is the dcache lookup function for rcu-walk name * resolution (store-free path walking) design described in * Documentation/filesystems/path-lookup.txt. * * This is not to be used outside core vfs. * * __d_lookup_rcu must only be used in rcu-walk mode, ie. with vfsmount lock * held, and rcu_read_lock held. The returned dentry must not be stored into * without taking d_lock and checking d_seq sequence count against @seq * returned here. * * A refcount may be taken on the found dentry with the __d_rcu_to_refcount * function. * * Alternatively, __d_lookup_rcu may be called again to look up the child of * the returned dentry, so long as its parent's seqlock is checked after the * child is looked up. Thus, an interlocking stepping of sequence lock checks * is formed, giving integrity down the path walk. */ struct dentry *__d_lookup_rcu(struct dentry *parent, struct qstr *name, unsigned *seq, struct inode **inode) { unsigned int len = name->len; unsigned int hash = name->hash; const unsigned char *str = name->name; |
b07ad9967 vfs: get rid of '... |
1669 |
struct hlist_bl_head *b = d_hash(parent, hash); |
ceb5bdc2d fs: dcache per-bu... |
1670 |
struct hlist_bl_node *node; |
31e6b01f4 fs: rcu-walk for ... |
1671 1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 |
struct dentry *dentry; /* * Note: There is significant duplication with __d_lookup_rcu which is * required to prevent single threaded performance regressions * especially on architectures where smp_rmb (in seqcounts) are costly. * Keep the two functions in sync. */ /* * The hash list is protected using RCU. * * Carefully use d_seq when comparing a candidate dentry, to avoid * races with d_move(). * * It is possible that concurrent renames can mess up our list * walk here and result in missing our dentry, resulting in the * false-negative result. d_lookup() protects against concurrent * renames using rename_lock seqlock. * |
b0a4bb830 fs: update commen... |
1691 |
* See Documentation/filesystems/path-lookup.txt for more details. |
31e6b01f4 fs: rcu-walk for ... |
1692 |
*/ |
b07ad9967 vfs: get rid of '... |
1693 |
hlist_bl_for_each_entry_rcu(dentry, node, b, d_hash) { |
31e6b01f4 fs: rcu-walk for ... |
1694 1695 1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 1709 |
struct inode *i; const char *tname; int tlen; if (dentry->d_name.hash != hash) continue; seqretry: *seq = read_seqcount_begin(&dentry->d_seq); if (dentry->d_parent != parent) continue; if (d_unhashed(dentry)) continue; tlen = dentry->d_name.len; tname = dentry->d_name.name; i = dentry->d_inode; |
e1bb57826 fs: prefetch inod... |
1710 |
prefetch(tname); |
31e6b01f4 fs: rcu-walk for ... |
1711 1712 1713 1714 1715 1716 1717 1718 |
/* * This seqcount check is required to ensure name and * len are loaded atomically, so as not to walk off the * edge of memory when walking. If we could load this * atomically some other way, we could drop this check. */ if (read_seqcount_retry(&dentry->d_seq, *seq)) goto seqretry; |
830c0f0ed vfs: renumber DCA... |
1719 |
if (unlikely(parent->d_flags & DCACHE_OP_COMPARE)) { |
31e6b01f4 fs: rcu-walk for ... |
1720 1721 1722 1723 1724 |
if (parent->d_op->d_compare(parent, *inode, dentry, i, tlen, tname, name)) continue; } else { |
9d55c369b fs: implement fas... |
1725 |
if (dentry_cmp(tname, tlen, str, len)) |
31e6b01f4 fs: rcu-walk for ... |
1726 1727 1728 1729 1730 1731 1732 1733 1734 1735 1736 1737 1738 1739 1740 |
continue; } /* * No extra seqcount check is required after the name * compare. The caller must perform a seqcount check in * order to do anything useful with the returned dentry * anyway. */ *inode = i; return dentry; } return NULL; } /** |
1da177e4c Linux-2.6.12-rc2 |
1741 1742 1743 |
* d_lookup - search for a dentry * @parent: parent dentry * @name: qstr of name we wish to find |
b04f784e5 fs: remove extra ... |
1744 |
* Returns: dentry, or NULL |
1da177e4c Linux-2.6.12-rc2 |
1745 |
* |
b04f784e5 fs: remove extra ... |
1746 1747 1748 1749 |
* d_lookup searches the children of the parent dentry for the name in * question. If the dentry is found its reference count is incremented and the * dentry is returned. The caller must use dput to free the entry when it has * finished using it. %NULL is returned if the dentry does not exist. |
1da177e4c Linux-2.6.12-rc2 |
1750 |
*/ |
31e6b01f4 fs: rcu-walk for ... |
1751 |
struct dentry *d_lookup(struct dentry *parent, struct qstr *name) |
1da177e4c Linux-2.6.12-rc2 |
1752 |
{ |
31e6b01f4 fs: rcu-walk for ... |
1753 |
struct dentry *dentry; |
949854d02 fs: Use rename lo... |
1754 |
unsigned seq; |
1da177e4c Linux-2.6.12-rc2 |
1755 1756 1757 1758 1759 1760 1761 1762 1763 |
do { seq = read_seqbegin(&rename_lock); dentry = __d_lookup(parent, name); if (dentry) break; } while (read_seqretry(&rename_lock, seq)); return dentry; } |
ec4f86059 fs/dcache.c: Codi... |
1764 |
EXPORT_SYMBOL(d_lookup); |
1da177e4c Linux-2.6.12-rc2 |
1765 |
|
31e6b01f4 fs: rcu-walk for ... |
1766 |
/** |
b04f784e5 fs: remove extra ... |
1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 |
* __d_lookup - search for a dentry (racy) * @parent: parent dentry * @name: qstr of name we wish to find * Returns: dentry, or NULL * * __d_lookup is like d_lookup, however it may (rarely) return a * false-negative result due to unrelated rename activity. * * __d_lookup is slightly faster by avoiding rename_lock read seqlock, * however it must be used carefully, eg. with a following d_lookup in * the case of failure. * * __d_lookup callers must be commented. */ |
31e6b01f4 fs: rcu-walk for ... |
1781 |
struct dentry *__d_lookup(struct dentry *parent, struct qstr *name) |
1da177e4c Linux-2.6.12-rc2 |
1782 1783 1784 1785 |
{ unsigned int len = name->len; unsigned int hash = name->hash; const unsigned char *str = name->name; |
b07ad9967 vfs: get rid of '... |
1786 |
struct hlist_bl_head *b = d_hash(parent, hash); |
ceb5bdc2d fs: dcache per-bu... |
1787 |
struct hlist_bl_node *node; |
31e6b01f4 fs: rcu-walk for ... |
1788 |
struct dentry *found = NULL; |
665a7583f [PATCH] Remove hl... |
1789 |
struct dentry *dentry; |
1da177e4c Linux-2.6.12-rc2 |
1790 |
|
b04f784e5 fs: remove extra ... |
1791 |
/* |
31e6b01f4 fs: rcu-walk for ... |
1792 1793 1794 1795 1796 1797 1798 |
* Note: There is significant duplication with __d_lookup_rcu which is * required to prevent single threaded performance regressions * especially on architectures where smp_rmb (in seqcounts) are costly. * Keep the two functions in sync. */ /* |
b04f784e5 fs: remove extra ... |
1799 1800 1801 1802 1803 1804 1805 1806 1807 1808 |
* The hash list is protected using RCU. * * Take d_lock when comparing a candidate dentry, to avoid races * with d_move(). * * It is possible that concurrent renames can mess up our list * walk here and result in missing our dentry, resulting in the * false-negative result. d_lookup() protects against concurrent * renames using rename_lock seqlock. * |
b0a4bb830 fs: update commen... |
1809 |
* See Documentation/filesystems/path-lookup.txt for more details. |
b04f784e5 fs: remove extra ... |
1810 |
*/ |
1da177e4c Linux-2.6.12-rc2 |
1811 1812 |
rcu_read_lock(); |
b07ad9967 vfs: get rid of '... |
1813 |
hlist_bl_for_each_entry_rcu(dentry, node, b, d_hash) { |
31e6b01f4 fs: rcu-walk for ... |
1814 1815 |
const char *tname; int tlen; |
1da177e4c Linux-2.6.12-rc2 |
1816 |
|
1da177e4c Linux-2.6.12-rc2 |
1817 1818 |
if (dentry->d_name.hash != hash) continue; |
1da177e4c Linux-2.6.12-rc2 |
1819 1820 |
spin_lock(&dentry->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
1821 1822 |
if (dentry->d_parent != parent) goto next; |
d0185c088 Fix NULL pointer ... |
1823 1824 |
if (d_unhashed(dentry)) goto next; |
1da177e4c Linux-2.6.12-rc2 |
1825 1826 1827 1828 |
/* * It is safe to compare names since d_move() cannot * change the qstr (protected by d_lock). */ |
31e6b01f4 fs: rcu-walk for ... |
1829 1830 |
tlen = dentry->d_name.len; tname = dentry->d_name.name; |
fb045adb9 fs: dcache reduce... |
1831 |
if (parent->d_flags & DCACHE_OP_COMPARE) { |
621e155a3 fs: change d_comp... |
1832 1833 |
if (parent->d_op->d_compare(parent, parent->d_inode, dentry, dentry->d_inode, |
31e6b01f4 fs: rcu-walk for ... |
1834 |
tlen, tname, name)) |
1da177e4c Linux-2.6.12-rc2 |
1835 1836 |
goto next; } else { |
9d55c369b fs: implement fas... |
1837 |
if (dentry_cmp(tname, tlen, str, len)) |
1da177e4c Linux-2.6.12-rc2 |
1838 1839 |
goto next; } |
b7ab39f63 fs: dcache scale ... |
1840 |
dentry->d_count++; |
d0185c088 Fix NULL pointer ... |
1841 |
found = dentry; |
1da177e4c Linux-2.6.12-rc2 |
1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 |
spin_unlock(&dentry->d_lock); break; next: spin_unlock(&dentry->d_lock); } rcu_read_unlock(); return found; } /** |
3e7e241f8 [PATCH] dcache: A... |
1853 1854 1855 1856 1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867 1868 |
* d_hash_and_lookup - hash the qstr then search for a dentry * @dir: Directory to search in * @name: qstr of name we wish to find * * On hash failure or on lookup failure NULL is returned. */ struct dentry *d_hash_and_lookup(struct dentry *dir, struct qstr *name) { struct dentry *dentry = NULL; /* * Check for a fs-specific hash function. Note that we must * calculate the standard hash first, as the d_op->d_hash() * routine may choose to leave the hash value unchanged. */ name->hash = full_name_hash(name->name, name->len); |
fb045adb9 fs: dcache reduce... |
1869 |
if (dir->d_flags & DCACHE_OP_HASH) { |
b1e6a015a fs: change d_hash... |
1870 |
if (dir->d_op->d_hash(dir, dir->d_inode, name) < 0) |
3e7e241f8 [PATCH] dcache: A... |
1871 1872 1873 1874 1875 1876 1877 1878 |
goto out; } dentry = d_lookup(dir, name); out: return dentry; } /** |
786a5e15b fs: d_validate fixes |
1879 |
* d_validate - verify dentry provided from insecure source (deprecated) |
1da177e4c Linux-2.6.12-rc2 |
1880 |
* @dentry: The dentry alleged to be valid child of @dparent |
ff5fdb614 fs: fix new dcach... |
1881 |
* @dparent: The parent dentry (known to be valid) |
1da177e4c Linux-2.6.12-rc2 |
1882 1883 1884 1885 |
* * An insecure source has sent us a dentry, here we verify it and dget() it. * This is used by ncpfs in its readdir implementation. * Zero is returned in the dentry is invalid. |
786a5e15b fs: d_validate fixes |
1886 1887 |
* * This function is slow for big directories, and deprecated, do not use it. |
1da177e4c Linux-2.6.12-rc2 |
1888 |
*/ |
d3a23e167 Revert "fs: use R... |
1889 |
int d_validate(struct dentry *dentry, struct dentry *dparent) |
1da177e4c Linux-2.6.12-rc2 |
1890 |
{ |
786a5e15b fs: d_validate fixes |
1891 |
struct dentry *child; |
d3a23e167 Revert "fs: use R... |
1892 |
|
2fd6b7f50 fs: dcache scale ... |
1893 |
spin_lock(&dparent->d_lock); |
786a5e15b fs: d_validate fixes |
1894 1895 |
list_for_each_entry(child, &dparent->d_subdirs, d_u.d_child) { if (dentry == child) { |
2fd6b7f50 fs: dcache scale ... |
1896 |
spin_lock_nested(&dentry->d_lock, DENTRY_D_LOCK_NESTED); |
dc0474be3 fs: dcache ration... |
1897 |
__dget_dlock(dentry); |
2fd6b7f50 fs: dcache scale ... |
1898 1899 |
spin_unlock(&dentry->d_lock); spin_unlock(&dparent->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
1900 1901 1902 |
return 1; } } |
2fd6b7f50 fs: dcache scale ... |
1903 |
spin_unlock(&dparent->d_lock); |
786a5e15b fs: d_validate fixes |
1904 |
|
1da177e4c Linux-2.6.12-rc2 |
1905 1906 |
return 0; } |
ec4f86059 fs/dcache.c: Codi... |
1907 |
EXPORT_SYMBOL(d_validate); |
1da177e4c Linux-2.6.12-rc2 |
1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928 1929 1930 1931 |
/* * When a file is deleted, we have two options: * - turn this dentry into a negative dentry * - unhash this dentry and free it. * * Usually, we want to just turn this into * a negative dentry, but if anybody else is * currently using the dentry or the inode * we can't do that and we fall back on removing * it from the hash queues and waiting for * it to be deleted later when it has no users */ /** * d_delete - delete a dentry * @dentry: The dentry to delete * * Turn the dentry into a negative dentry if possible, otherwise * remove it from the hash queues so it can be deleted later */ void d_delete(struct dentry * dentry) { |
873feea09 fs: dcache per-in... |
1932 |
struct inode *inode; |
7a91bf7f5 [PATCH] fsnotify_... |
1933 |
int isdir = 0; |
1da177e4c Linux-2.6.12-rc2 |
1934 1935 1936 |
/* * Are we the only user? */ |
357f8e658 fs: dcache reduce... |
1937 |
again: |
1da177e4c Linux-2.6.12-rc2 |
1938 |
spin_lock(&dentry->d_lock); |
873feea09 fs: dcache per-in... |
1939 1940 |
inode = dentry->d_inode; isdir = S_ISDIR(inode->i_mode); |
b7ab39f63 fs: dcache scale ... |
1941 |
if (dentry->d_count == 1) { |
873feea09 fs: dcache per-in... |
1942 |
if (inode && !spin_trylock(&inode->i_lock)) { |
357f8e658 fs: dcache reduce... |
1943 1944 1945 1946 |
spin_unlock(&dentry->d_lock); cpu_relax(); goto again; } |
13e3c5e5b clean DCACHE_CANT... |
1947 |
dentry->d_flags &= ~DCACHE_CANT_MOUNT; |
31e6b01f4 fs: rcu-walk for ... |
1948 |
dentry_unlink_inode(dentry); |
7a91bf7f5 [PATCH] fsnotify_... |
1949 |
fsnotify_nameremove(dentry, isdir); |
1da177e4c Linux-2.6.12-rc2 |
1950 1951 1952 1953 1954 1955 1956 |
return; } if (!d_unhashed(dentry)) __d_drop(dentry); spin_unlock(&dentry->d_lock); |
7a91bf7f5 [PATCH] fsnotify_... |
1957 1958 |
fsnotify_nameremove(dentry, isdir); |
1da177e4c Linux-2.6.12-rc2 |
1959 |
} |
ec4f86059 fs/dcache.c: Codi... |
1960 |
EXPORT_SYMBOL(d_delete); |
1da177e4c Linux-2.6.12-rc2 |
1961 |
|
b07ad9967 vfs: get rid of '... |
1962 |
static void __d_rehash(struct dentry * entry, struct hlist_bl_head *b) |
1da177e4c Linux-2.6.12-rc2 |
1963 |
{ |
ceb5bdc2d fs: dcache per-bu... |
1964 |
BUG_ON(!d_unhashed(entry)); |
1879fd6a2 add hlist_bl_lock... |
1965 |
hlist_bl_lock(b); |
dea3667bc vfs: get rid of i... |
1966 |
entry->d_flags |= DCACHE_RCUACCESS; |
b07ad9967 vfs: get rid of '... |
1967 |
hlist_bl_add_head_rcu(&entry->d_hash, b); |
1879fd6a2 add hlist_bl_lock... |
1968 |
hlist_bl_unlock(b); |
1da177e4c Linux-2.6.12-rc2 |
1969 |
} |
770bfad84 NFS: Add dentry m... |
1970 1971 1972 1973 |
static void _d_rehash(struct dentry * entry) { __d_rehash(entry, d_hash(entry->d_parent, entry->d_name.hash)); } |
1da177e4c Linux-2.6.12-rc2 |
1974 1975 1976 1977 1978 1979 1980 1981 1982 |
/** * d_rehash - add an entry back to the hash * @entry: dentry to add to the hash * * Adds a dentry to the hash according to its name. */ void d_rehash(struct dentry * entry) { |
1da177e4c Linux-2.6.12-rc2 |
1983 |
spin_lock(&entry->d_lock); |
770bfad84 NFS: Add dentry m... |
1984 |
_d_rehash(entry); |
1da177e4c Linux-2.6.12-rc2 |
1985 |
spin_unlock(&entry->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
1986 |
} |
ec4f86059 fs/dcache.c: Codi... |
1987 |
EXPORT_SYMBOL(d_rehash); |
1da177e4c Linux-2.6.12-rc2 |
1988 |
|
fb2d5b86a fs: name case upd... |
1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 |
/** * dentry_update_name_case - update case insensitive dentry with a new name * @dentry: dentry to be updated * @name: new name * * Update a case insensitive dentry with new case of name. * * dentry must have been returned by d_lookup with name @name. Old and new * name lengths must match (ie. no d_compare which allows mismatched name * lengths). * * Parent inode i_mutex must be held over d_lookup and into this call (to * keep renames and concurrent inserts, and readdir(2) away). */ void dentry_update_name_case(struct dentry *dentry, struct qstr *name) { |
7ebfa57f6 vfs: fix incorrec... |
2005 |
BUG_ON(!mutex_is_locked(&dentry->d_parent->d_inode->i_mutex)); |
fb2d5b86a fs: name case upd... |
2006 |
BUG_ON(dentry->d_name.len != name->len); /* d_lookup gives this */ |
fb2d5b86a fs: name case upd... |
2007 |
spin_lock(&dentry->d_lock); |
31e6b01f4 fs: rcu-walk for ... |
2008 |
write_seqcount_begin(&dentry->d_seq); |
fb2d5b86a fs: name case upd... |
2009 |
memcpy((unsigned char *)dentry->d_name.name, name->name, name->len); |
31e6b01f4 fs: rcu-walk for ... |
2010 |
write_seqcount_end(&dentry->d_seq); |
fb2d5b86a fs: name case upd... |
2011 |
spin_unlock(&dentry->d_lock); |
fb2d5b86a fs: name case upd... |
2012 2013 |
} EXPORT_SYMBOL(dentry_update_name_case); |
1da177e4c Linux-2.6.12-rc2 |
2014 2015 2016 2017 2018 2019 2020 |
static void switch_names(struct dentry *dentry, struct dentry *target) { if (dname_external(target)) { if (dname_external(dentry)) { /* * Both external: swap the pointers */ |
9a8d5bb4a generic swap(): d... |
2021 |
swap(target->d_name.name, dentry->d_name.name); |
1da177e4c Linux-2.6.12-rc2 |
2022 2023 2024 2025 2026 |
} else { /* * dentry:internal, target:external. Steal target's * storage and make target internal. */ |
321bcf921 dcache: don't exp... |
2027 2028 |
memcpy(target->d_iname, dentry->d_name.name, dentry->d_name.len + 1); |
1da177e4c Linux-2.6.12-rc2 |
2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 |
dentry->d_name.name = target->d_name.name; target->d_name.name = target->d_iname; } } else { if (dname_external(dentry)) { /* * dentry:external, target:internal. Give dentry's * storage to target and make dentry internal */ memcpy(dentry->d_iname, target->d_name.name, target->d_name.len + 1); target->d_name.name = dentry->d_name.name; dentry->d_name.name = dentry->d_iname; } else { /* * Both are internal. Just copy target to dentry */ memcpy(dentry->d_iname, target->d_name.name, target->d_name.len + 1); |
dc711ca35 fix switch_names(... |
2048 2049 |
dentry->d_name.len = target->d_name.len; return; |
1da177e4c Linux-2.6.12-rc2 |
2050 2051 |
} } |
9a8d5bb4a generic swap(): d... |
2052 |
swap(dentry->d_name.len, target->d_name.len); |
1da177e4c Linux-2.6.12-rc2 |
2053 |
} |
2fd6b7f50 fs: dcache scale ... |
2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085 2086 2087 2088 |
static void dentry_lock_for_move(struct dentry *dentry, struct dentry *target) { /* * XXXX: do we really need to take target->d_lock? */ if (IS_ROOT(dentry) || dentry->d_parent == target->d_parent) spin_lock(&target->d_parent->d_lock); else { if (d_ancestor(dentry->d_parent, target->d_parent)) { spin_lock(&dentry->d_parent->d_lock); spin_lock_nested(&target->d_parent->d_lock, DENTRY_D_LOCK_NESTED); } else { spin_lock(&target->d_parent->d_lock); spin_lock_nested(&dentry->d_parent->d_lock, DENTRY_D_LOCK_NESTED); } } if (target < dentry) { spin_lock_nested(&target->d_lock, 2); spin_lock_nested(&dentry->d_lock, 3); } else { spin_lock_nested(&dentry->d_lock, 2); spin_lock_nested(&target->d_lock, 3); } } static void dentry_unlock_parents_for_move(struct dentry *dentry, struct dentry *target) { if (target->d_parent != dentry->d_parent) spin_unlock(&dentry->d_parent->d_lock); if (target->d_parent != target) spin_unlock(&target->d_parent->d_lock); } |
1da177e4c Linux-2.6.12-rc2 |
2089 |
/* |
2fd6b7f50 fs: dcache scale ... |
2090 2091 2092 2093 2094 2095 2096 2097 2098 |
* When switching names, the actual string doesn't strictly have to * be preserved in the target - because we're dropping the target * anyway. As such, we can just do a simple memcpy() to copy over * the new name before we switch. * * Note that we have to be a lot more careful about getting the hash * switched - we have to switch the hash value properly even if it * then no longer matches the actual (corrupted) string of the target. * The hash value has to match the hash queue that the dentry is on.. |
1da177e4c Linux-2.6.12-rc2 |
2099 |
*/ |
9eaef27b3 [PATCH] VFS: Make... |
2100 |
/* |
183675011 fix loop checks i... |
2101 |
* __d_move - move a dentry |
1da177e4c Linux-2.6.12-rc2 |
2102 2103 2104 2105 |
* @dentry: entry to move * @target: new dentry * * Update the dcache to reflect the move of a file name. Negative |
c46c88774 vfs: document loc... |
2106 2107 2108 |
* dcache entries should not be moved in this way. Caller must hold * rename_lock, the i_mutex of the source and target directories, * and the sb->s_vfs_rename_mutex if they differ. See lock_rename(). |
1da177e4c Linux-2.6.12-rc2 |
2109 |
*/ |
183675011 fix loop checks i... |
2110 |
static void __d_move(struct dentry * dentry, struct dentry * target) |
1da177e4c Linux-2.6.12-rc2 |
2111 |
{ |
1da177e4c Linux-2.6.12-rc2 |
2112 2113 2114 |
if (!dentry->d_inode) printk(KERN_WARNING "VFS: moving negative dcache entry "); |
2fd6b7f50 fs: dcache scale ... |
2115 2116 |
BUG_ON(d_ancestor(dentry, target)); BUG_ON(d_ancestor(target, dentry)); |
2fd6b7f50 fs: dcache scale ... |
2117 |
dentry_lock_for_move(dentry, target); |
1da177e4c Linux-2.6.12-rc2 |
2118 |
|
31e6b01f4 fs: rcu-walk for ... |
2119 2120 |
write_seqcount_begin(&dentry->d_seq); write_seqcount_begin(&target->d_seq); |
ceb5bdc2d fs: dcache per-bu... |
2121 2122 2123 2124 2125 2126 2127 |
/* __d_drop does write_seqcount_barrier, but they're OK to nest. */ /* * Move the dentry to the target hash queue. Don't bother checking * for the same hash queue because of how unlikely it is. */ __d_drop(dentry); |
789680d1e fs: dcache scale ... |
2128 |
__d_rehash(dentry, d_hash(target->d_parent, target->d_name.hash)); |
1da177e4c Linux-2.6.12-rc2 |
2129 2130 2131 |
/* Unhash the target: dput() will then get rid of it */ __d_drop(target); |
5160ee6fc [PATCH] shrink de... |
2132 2133 |
list_del(&dentry->d_u.d_child); list_del(&target->d_u.d_child); |
1da177e4c Linux-2.6.12-rc2 |
2134 2135 2136 |
/* Switch the names.. */ switch_names(dentry, target); |
9a8d5bb4a generic swap(): d... |
2137 |
swap(dentry->d_name.hash, target->d_name.hash); |
1da177e4c Linux-2.6.12-rc2 |
2138 2139 2140 2141 2142 |
/* ... and switch the parents */ if (IS_ROOT(dentry)) { dentry->d_parent = target->d_parent; target->d_parent = target; |
5160ee6fc [PATCH] shrink de... |
2143 |
INIT_LIST_HEAD(&target->d_u.d_child); |
1da177e4c Linux-2.6.12-rc2 |
2144 |
} else { |
9a8d5bb4a generic swap(): d... |
2145 |
swap(dentry->d_parent, target->d_parent); |
1da177e4c Linux-2.6.12-rc2 |
2146 2147 |
/* And add them back to the (new) parent lists */ |
5160ee6fc [PATCH] shrink de... |
2148 |
list_add(&target->d_u.d_child, &target->d_parent->d_subdirs); |
1da177e4c Linux-2.6.12-rc2 |
2149 |
} |
5160ee6fc [PATCH] shrink de... |
2150 |
list_add(&dentry->d_u.d_child, &dentry->d_parent->d_subdirs); |
2fd6b7f50 fs: dcache scale ... |
2151 |
|
31e6b01f4 fs: rcu-walk for ... |
2152 2153 |
write_seqcount_end(&target->d_seq); write_seqcount_end(&dentry->d_seq); |
2fd6b7f50 fs: dcache scale ... |
2154 |
dentry_unlock_parents_for_move(dentry, target); |
1da177e4c Linux-2.6.12-rc2 |
2155 |
spin_unlock(&target->d_lock); |
c32ccd87b [PATCH] inotify: ... |
2156 |
fsnotify_d_move(dentry); |
1da177e4c Linux-2.6.12-rc2 |
2157 |
spin_unlock(&dentry->d_lock); |
183675011 fix loop checks i... |
2158 2159 2160 2161 2162 2163 2164 2165 |
} /* * d_move - move a dentry * @dentry: entry to move * @target: new dentry * * Update the dcache to reflect the move of a file name. Negative |
c46c88774 vfs: document loc... |
2166 2167 |
* dcache entries should not be moved in this way. See the locking * requirements for __d_move. |
183675011 fix loop checks i... |
2168 2169 2170 2171 2172 |
*/ void d_move(struct dentry *dentry, struct dentry *target) { write_seqlock(&rename_lock); __d_move(dentry, target); |
1da177e4c Linux-2.6.12-rc2 |
2173 |
write_sequnlock(&rename_lock); |
9eaef27b3 [PATCH] VFS: Make... |
2174 |
} |
ec4f86059 fs/dcache.c: Codi... |
2175 |
EXPORT_SYMBOL(d_move); |
1da177e4c Linux-2.6.12-rc2 |
2176 |
|
e2761a116 [PATCH vfs-2.6 2/... |
2177 2178 2179 2180 2181 2182 2183 |
/** * d_ancestor - search for an ancestor * @p1: ancestor dentry * @p2: child dentry * * Returns the ancestor dentry of p2 which is a child of p1, if p1 is * an ancestor of p2, else NULL. |
9eaef27b3 [PATCH] VFS: Make... |
2184 |
*/ |
e2761a116 [PATCH vfs-2.6 2/... |
2185 |
struct dentry *d_ancestor(struct dentry *p1, struct dentry *p2) |
9eaef27b3 [PATCH] VFS: Make... |
2186 2187 |
{ struct dentry *p; |
871c0067d [PATCH vfs-2.6 1/... |
2188 |
for (p = p2; !IS_ROOT(p); p = p->d_parent) { |
9eaef27b3 [PATCH] VFS: Make... |
2189 |
if (p->d_parent == p1) |
e2761a116 [PATCH vfs-2.6 2/... |
2190 |
return p; |
9eaef27b3 [PATCH] VFS: Make... |
2191 |
} |
e2761a116 [PATCH vfs-2.6 2/... |
2192 |
return NULL; |
9eaef27b3 [PATCH] VFS: Make... |
2193 2194 2195 2196 2197 2198 |
} /* * This helper attempts to cope with remotely renamed directories * * It assumes that the caller is already holding |
183675011 fix loop checks i... |
2199 |
* dentry->d_parent->d_inode->i_mutex, inode->i_lock and rename_lock |
9eaef27b3 [PATCH] VFS: Make... |
2200 2201 2202 |
* * Note: If ever the locking in lock_rename() changes, then please * remember to update this too... |
9eaef27b3 [PATCH] VFS: Make... |
2203 |
*/ |
873feea09 fs: dcache per-in... |
2204 2205 |
static struct dentry *__d_unalias(struct inode *inode, struct dentry *dentry, struct dentry *alias) |
9eaef27b3 [PATCH] VFS: Make... |
2206 2207 2208 2209 2210 2211 2212 |
{ struct mutex *m1 = NULL, *m2 = NULL; struct dentry *ret; /* If alias and dentry share a parent, then no extra locks required */ if (alias->d_parent == dentry->d_parent) goto out_unalias; |
9eaef27b3 [PATCH] VFS: Make... |
2213 2214 2215 2216 2217 2218 2219 2220 2221 |
/* See lock_rename() */ ret = ERR_PTR(-EBUSY); if (!mutex_trylock(&dentry->d_sb->s_vfs_rename_mutex)) goto out_err; m1 = &dentry->d_sb->s_vfs_rename_mutex; if (!mutex_trylock(&alias->d_parent->d_inode->i_mutex)) goto out_err; m2 = &alias->d_parent->d_inode->i_mutex; out_unalias: |
183675011 fix loop checks i... |
2222 |
__d_move(alias, dentry); |
9eaef27b3 [PATCH] VFS: Make... |
2223 2224 |
ret = alias; out_err: |
873feea09 fs: dcache per-in... |
2225 |
spin_unlock(&inode->i_lock); |
9eaef27b3 [PATCH] VFS: Make... |
2226 2227 2228 2229 2230 2231 2232 2233 |
if (m2) mutex_unlock(m2); if (m1) mutex_unlock(m1); return ret; } /* |
770bfad84 NFS: Add dentry m... |
2234 2235 |
* Prepare an anonymous dentry for life in the superblock's dentry tree as a * named dentry in place of the dentry to be replaced. |
2fd6b7f50 fs: dcache scale ... |
2236 |
* returns with anon->d_lock held! |
770bfad84 NFS: Add dentry m... |
2237 2238 2239 2240 |
*/ static void __d_materialise_dentry(struct dentry *dentry, struct dentry *anon) { struct dentry *dparent, *aparent; |
2fd6b7f50 fs: dcache scale ... |
2241 |
dentry_lock_for_move(anon, dentry); |
770bfad84 NFS: Add dentry m... |
2242 |
|
31e6b01f4 fs: rcu-walk for ... |
2243 2244 |
write_seqcount_begin(&dentry->d_seq); write_seqcount_begin(&anon->d_seq); |
770bfad84 NFS: Add dentry m... |
2245 2246 |
dparent = dentry->d_parent; aparent = anon->d_parent; |
2fd6b7f50 fs: dcache scale ... |
2247 2248 |
switch_names(dentry, anon); swap(dentry->d_name.hash, anon->d_name.hash); |
770bfad84 NFS: Add dentry m... |
2249 2250 2251 2252 2253 2254 2255 2256 2257 2258 2259 2260 2261 |
dentry->d_parent = (aparent == anon) ? dentry : aparent; list_del(&dentry->d_u.d_child); if (!IS_ROOT(dentry)) list_add(&dentry->d_u.d_child, &dentry->d_parent->d_subdirs); else INIT_LIST_HEAD(&dentry->d_u.d_child); anon->d_parent = (dparent == dentry) ? anon : dparent; list_del(&anon->d_u.d_child); if (!IS_ROOT(anon)) list_add(&anon->d_u.d_child, &anon->d_parent->d_subdirs); else INIT_LIST_HEAD(&anon->d_u.d_child); |
31e6b01f4 fs: rcu-walk for ... |
2262 2263 |
write_seqcount_end(&dentry->d_seq); write_seqcount_end(&anon->d_seq); |
2fd6b7f50 fs: dcache scale ... |
2264 2265 2266 2267 |
dentry_unlock_parents_for_move(anon, dentry); spin_unlock(&dentry->d_lock); /* anon->d_lock still locked, returns locked */ |
770bfad84 NFS: Add dentry m... |
2268 2269 2270 2271 2272 2273 2274 2275 2276 |
anon->d_flags &= ~DCACHE_DISCONNECTED; } /** * d_materialise_unique - introduce an inode into the tree * @dentry: candidate dentry * @inode: inode to bind to the dentry, to which aliases may be attached * * Introduces an dentry into the tree, substituting an extant disconnected |
c46c88774 vfs: document loc... |
2277 2278 |
* root directory alias in its place if there is one. Caller must hold the * i_mutex of the parent directory. |
770bfad84 NFS: Add dentry m... |
2279 2280 2281 |
*/ struct dentry *d_materialise_unique(struct dentry *dentry, struct inode *inode) { |
9eaef27b3 [PATCH] VFS: Make... |
2282 |
struct dentry *actual; |
770bfad84 NFS: Add dentry m... |
2283 2284 |
BUG_ON(!d_unhashed(dentry)); |
770bfad84 NFS: Add dentry m... |
2285 2286 |
if (!inode) { actual = dentry; |
360da9002 [PATCH vfs-2.6 3/... |
2287 |
__d_instantiate(dentry, NULL); |
357f8e658 fs: dcache reduce... |
2288 2289 |
d_rehash(actual); goto out_nolock; |
770bfad84 NFS: Add dentry m... |
2290 |
} |
873feea09 fs: dcache per-in... |
2291 |
spin_lock(&inode->i_lock); |
357f8e658 fs: dcache reduce... |
2292 |
|
9eaef27b3 [PATCH] VFS: Make... |
2293 2294 2295 2296 2297 2298 2299 |
if (S_ISDIR(inode->i_mode)) { struct dentry *alias; /* Does an aliased dentry already exist? */ alias = __d_find_alias(inode, 0); if (alias) { actual = alias; |
183675011 fix loop checks i... |
2300 2301 2302 2303 2304 2305 2306 2307 |
write_seqlock(&rename_lock); if (d_ancestor(alias, dentry)) { /* Check for loops */ actual = ERR_PTR(-ELOOP); } else if (IS_ROOT(alias)) { /* Is this an anonymous mountpoint that we * could splice into our tree? */ |
9eaef27b3 [PATCH] VFS: Make... |
2308 |
__d_materialise_dentry(dentry, alias); |
183675011 fix loop checks i... |
2309 |
write_sequnlock(&rename_lock); |
9eaef27b3 [PATCH] VFS: Make... |
2310 2311 |
__d_drop(alias); goto found; |
183675011 fix loop checks i... |
2312 2313 2314 2315 |
} else { /* Nope, but we must(!) avoid directory * aliasing */ actual = __d_unalias(inode, dentry, alias); |
9eaef27b3 [PATCH] VFS: Make... |
2316 |
} |
183675011 fix loop checks i... |
2317 |
write_sequnlock(&rename_lock); |
dd179946d VFS: Log the fact... |
2318 2319 2320 2321 2322 2323 2324 2325 2326 |
if (IS_ERR(actual)) { if (PTR_ERR(actual) == -ELOOP) pr_warn_ratelimited( "VFS: Lookup of '%s' in %s %s" " would have caused loop ", dentry->d_name.name, inode->i_sb->s_type->name, inode->i_sb->s_id); |
9eaef27b3 [PATCH] VFS: Make... |
2327 |
dput(alias); |
dd179946d VFS: Log the fact... |
2328 |
} |
9eaef27b3 [PATCH] VFS: Make... |
2329 2330 |
goto out_nolock; } |
770bfad84 NFS: Add dentry m... |
2331 2332 2333 2334 2335 2336 |
} /* Add a unique reference */ actual = __d_instantiate_unique(dentry, inode); if (!actual) actual = dentry; |
357f8e658 fs: dcache reduce... |
2337 2338 |
else BUG_ON(!d_unhashed(actual)); |
770bfad84 NFS: Add dentry m... |
2339 |
|
770bfad84 NFS: Add dentry m... |
2340 2341 2342 2343 |
spin_lock(&actual->d_lock); found: _d_rehash(actual); spin_unlock(&actual->d_lock); |
873feea09 fs: dcache per-in... |
2344 |
spin_unlock(&inode->i_lock); |
9eaef27b3 [PATCH] VFS: Make... |
2345 |
out_nolock: |
770bfad84 NFS: Add dentry m... |
2346 2347 2348 2349 2350 2351 2352 |
if (actual == dentry) { security_d_instantiate(dentry, inode); return NULL; } iput(inode); return actual; |
770bfad84 NFS: Add dentry m... |
2353 |
} |
ec4f86059 fs/dcache.c: Codi... |
2354 |
EXPORT_SYMBOL_GPL(d_materialise_unique); |
770bfad84 NFS: Add dentry m... |
2355 |
|
cdd16d026 [patch 2/3] vfs: ... |
2356 |
static int prepend(char **buffer, int *buflen, const char *str, int namelen) |
6092d0481 [patch 1/7] vfs: ... |
2357 2358 2359 2360 2361 2362 2363 2364 |
{ *buflen -= namelen; if (*buflen < 0) return -ENAMETOOLONG; *buffer -= namelen; memcpy(*buffer, str, namelen); return 0; } |
cdd16d026 [patch 2/3] vfs: ... |
2365 2366 2367 2368 |
static int prepend_name(char **buffer, int *buflen, struct qstr *name) { return prepend(buffer, buflen, name->name, name->len); } |
1da177e4c Linux-2.6.12-rc2 |
2369 |
/** |
208898c17 fs: fix kernel-do... |
2370 |
* prepend_path - Prepend path string to a buffer |
9d1bc6013 [patch 2/7] vfs: ... |
2371 |
* @path: the dentry/vfsmount to report |
02125a826 fix apparmor dere... |
2372 |
* @root: root vfsmnt/dentry |
f2eb6575d vfs: add prepend_... |
2373 2374 |
* @buffer: pointer to the end of the buffer * @buflen: pointer to buffer length |
552ce544e Revert "[PATCH] F... |
2375 |
* |
949854d02 fs: Use rename lo... |
2376 |
* Caller holds the rename_lock. |
1da177e4c Linux-2.6.12-rc2 |
2377 |
*/ |
02125a826 fix apparmor dere... |
2378 2379 |
static int prepend_path(const struct path *path, const struct path *root, |
f2eb6575d vfs: add prepend_... |
2380 |
char **buffer, int *buflen) |
1da177e4c Linux-2.6.12-rc2 |
2381 |
{ |
9d1bc6013 [patch 2/7] vfs: ... |
2382 2383 |
struct dentry *dentry = path->dentry; struct vfsmount *vfsmnt = path->mnt; |
0714a5338 vfs: now it can b... |
2384 |
struct mount *mnt = real_mount(vfsmnt); |
f2eb6575d vfs: add prepend_... |
2385 2386 |
bool slash = false; int error = 0; |
6092d0481 [patch 1/7] vfs: ... |
2387 |
|
99b7db7b8 fs: brlock vfsmou... |
2388 |
br_read_lock(vfsmount_lock); |
f2eb6575d vfs: add prepend_... |
2389 |
while (dentry != root->dentry || vfsmnt != root->mnt) { |
1da177e4c Linux-2.6.12-rc2 |
2390 |
struct dentry * parent; |
1da177e4c Linux-2.6.12-rc2 |
2391 |
if (dentry == vfsmnt->mnt_root || IS_ROOT(dentry)) { |
552ce544e Revert "[PATCH] F... |
2392 |
/* Global root? */ |
676da58df vfs: spread struc... |
2393 |
if (!mnt_has_parent(mnt)) |
1da177e4c Linux-2.6.12-rc2 |
2394 |
goto global_root; |
a73324da7 vfs: move mnt_mou... |
2395 |
dentry = mnt->mnt_mountpoint; |
0714a5338 vfs: now it can b... |
2396 2397 |
mnt = mnt->mnt_parent; vfsmnt = &mnt->mnt; |
1da177e4c Linux-2.6.12-rc2 |
2398 2399 2400 2401 |
continue; } parent = dentry->d_parent; prefetch(parent); |
9abca3608 fs: increase d_na... |
2402 |
spin_lock(&dentry->d_lock); |
f2eb6575d vfs: add prepend_... |
2403 |
error = prepend_name(buffer, buflen, &dentry->d_name); |
9abca3608 fs: increase d_na... |
2404 |
spin_unlock(&dentry->d_lock); |
f2eb6575d vfs: add prepend_... |
2405 2406 2407 2408 2409 2410 |
if (!error) error = prepend(buffer, buflen, "/", 1); if (error) break; slash = true; |
1da177e4c Linux-2.6.12-rc2 |
2411 2412 |
dentry = parent; } |
f2eb6575d vfs: add prepend_... |
2413 2414 |
if (!error && !slash) error = prepend(buffer, buflen, "/", 1); |
02125a826 fix apparmor dere... |
2415 |
out: |
99b7db7b8 fs: brlock vfsmou... |
2416 |
br_read_unlock(vfsmount_lock); |
f2eb6575d vfs: add prepend_... |
2417 |
return error; |
1da177e4c Linux-2.6.12-rc2 |
2418 2419 |
global_root: |
98dc568bc vfs: __d_path: do... |
2420 2421 2422 2423 2424 2425 2426 2427 2428 2429 |
/* * Filesystems needing to implement special "root names" * should do so with ->d_dname() */ if (IS_ROOT(dentry) && (dentry->d_name.len != 1 || dentry->d_name.name[0] != '/')) { WARN(1, "Root dentry has weird name <%.*s> ", (int) dentry->d_name.len, dentry->d_name.name); } |
02125a826 fix apparmor dere... |
2430 2431 2432 |
if (!slash) error = prepend(buffer, buflen, "/", 1); if (!error) |
143c8c91c vfs: mnt_ns moved... |
2433 |
error = real_mount(vfsmnt)->mnt_ns ? 1 : 2; |
be285c712 [patch 3/3] vfs: ... |
2434 |
goto out; |
f2eb6575d vfs: add prepend_... |
2435 |
} |
be285c712 [patch 3/3] vfs: ... |
2436 |
|
f2eb6575d vfs: add prepend_... |
2437 2438 2439 |
/** * __d_path - return the path of a dentry * @path: the dentry/vfsmount to report |
02125a826 fix apparmor dere... |
2440 |
* @root: root vfsmnt/dentry |
cd956a1c0 fs/dcache: fix fu... |
2441 |
* @buf: buffer to return value in |
f2eb6575d vfs: add prepend_... |
2442 2443 |
* @buflen: buffer length * |
ffd1f4ed5 vfs: only add " (... |
2444 |
* Convert a dentry into an ASCII path name. |
f2eb6575d vfs: add prepend_... |
2445 2446 2447 2448 |
* * Returns a pointer into the buffer or an error code if the * path was too long. * |
be148247c fs: take dcache_l... |
2449 |
* "buflen" should be positive. |
f2eb6575d vfs: add prepend_... |
2450 |
* |
02125a826 fix apparmor dere... |
2451 |
* If the path is not reachable from the supplied root, return %NULL. |
f2eb6575d vfs: add prepend_... |
2452 |
*/ |
02125a826 fix apparmor dere... |
2453 2454 |
char *__d_path(const struct path *path, const struct path *root, |
f2eb6575d vfs: add prepend_... |
2455 2456 2457 2458 2459 2460 |
char *buf, int buflen) { char *res = buf + buflen; int error; prepend(&res, &buflen, "\0", 1); |
949854d02 fs: Use rename lo... |
2461 |
write_seqlock(&rename_lock); |
f2eb6575d vfs: add prepend_... |
2462 |
error = prepend_path(path, root, &res, &buflen); |
949854d02 fs: Use rename lo... |
2463 |
write_sequnlock(&rename_lock); |
be148247c fs: take dcache_l... |
2464 |
|
02125a826 fix apparmor dere... |
2465 2466 2467 2468 2469 2470 2471 2472 2473 2474 2475 2476 2477 2478 2479 2480 2481 2482 2483 2484 2485 2486 |
if (error < 0) return ERR_PTR(error); if (error > 0) return NULL; return res; } char *d_absolute_path(const struct path *path, char *buf, int buflen) { struct path root = {}; char *res = buf + buflen; int error; prepend(&res, &buflen, "\0", 1); write_seqlock(&rename_lock); error = prepend_path(path, &root, &res, &buflen); write_sequnlock(&rename_lock); if (error > 1) error = -EINVAL; if (error < 0) |
f2eb6575d vfs: add prepend_... |
2487 |
return ERR_PTR(error); |
f2eb6575d vfs: add prepend_... |
2488 |
return res; |
1da177e4c Linux-2.6.12-rc2 |
2489 |
} |
ffd1f4ed5 vfs: only add " (... |
2490 2491 2492 |
/* * same as __d_path but appends "(deleted)" for unlinked files. */ |
02125a826 fix apparmor dere... |
2493 2494 2495 |
static int path_with_deleted(const struct path *path, const struct path *root, char **buf, int *buflen) |
ffd1f4ed5 vfs: only add " (... |
2496 2497 2498 2499 2500 2501 2502 2503 2504 2505 |
{ prepend(buf, buflen, "\0", 1); if (d_unlinked(path->dentry)) { int error = prepend(buf, buflen, " (deleted)", 10); if (error) return error; } return prepend_path(path, root, buf, buflen); } |
8df9d1a41 vfs: show unreach... |
2506 2507 2508 2509 |
static int prepend_unreachable(char **buffer, int *buflen) { return prepend(buffer, buflen, "(unreachable)", 13); } |
a03a8a709 d_path: kerneldoc... |
2510 2511 |
/** * d_path - return the path of a dentry |
cf28b4863 d_path: Make d_pa... |
2512 |
* @path: path to report |
a03a8a709 d_path: kerneldoc... |
2513 2514 2515 2516 2517 2518 |
* @buf: buffer to return value in * @buflen: buffer length * * Convert a dentry into an ASCII path name. If the entry has been deleted * the string " (deleted)" is appended. Note that this is ambiguous. * |
52afeefb9 expand some comme... |
2519 2520 2521 2522 |
* Returns a pointer into the buffer or an error code if the path was * too long. Note: Callers should use the returned pointer, not the passed * in buffer, to use the name! The implementation often starts at an offset * into the buffer, and may leave 0 bytes at the start. |
a03a8a709 d_path: kerneldoc... |
2523 |
* |
31f3e0b3a [patch 1/3] vfs: ... |
2524 |
* "buflen" should be positive. |
a03a8a709 d_path: kerneldoc... |
2525 |
*/ |
20d4fdc1a [patch 2/4] fs: m... |
2526 |
char *d_path(const struct path *path, char *buf, int buflen) |
1da177e4c Linux-2.6.12-rc2 |
2527 |
{ |
ffd1f4ed5 vfs: only add " (... |
2528 |
char *res = buf + buflen; |
6ac08c39a Use struct path i... |
2529 |
struct path root; |
ffd1f4ed5 vfs: only add " (... |
2530 |
int error; |
1da177e4c Linux-2.6.12-rc2 |
2531 |
|
c23fbb6bc VFS: delay the de... |
2532 2533 2534 2535 2536 2537 2538 |
/* * We have various synthetic filesystems that never get mounted. On * these filesystems dentries are never used for lookup purposes, and * thus don't need to be hashed. They also don't need a name until a * user wants to identify the object in /proc/pid/fd/. The little hack * below allows us to generate a name for these objects on demand: */ |
cf28b4863 d_path: Make d_pa... |
2539 2540 |
if (path->dentry->d_op && path->dentry->d_op->d_dname) return path->dentry->d_op->d_dname(path->dentry, buf, buflen); |
c23fbb6bc VFS: delay the de... |
2541 |
|
f7ad3c6be vfs: add helpers ... |
2542 |
get_fs_root(current->fs, &root); |
949854d02 fs: Use rename lo... |
2543 |
write_seqlock(&rename_lock); |
02125a826 fix apparmor dere... |
2544 2545 |
error = path_with_deleted(path, &root, &res, &buflen); if (error < 0) |
ffd1f4ed5 vfs: only add " (... |
2546 |
res = ERR_PTR(error); |
949854d02 fs: Use rename lo... |
2547 |
write_sequnlock(&rename_lock); |
6ac08c39a Use struct path i... |
2548 |
path_put(&root); |
1da177e4c Linux-2.6.12-rc2 |
2549 2550 |
return res; } |
ec4f86059 fs/dcache.c: Codi... |
2551 |
EXPORT_SYMBOL(d_path); |
1da177e4c Linux-2.6.12-rc2 |
2552 |
|
8df9d1a41 vfs: show unreach... |
2553 2554 2555 2556 2557 2558 2559 2560 2561 2562 2563 2564 2565 |
/** * d_path_with_unreachable - return the path of a dentry * @path: path to report * @buf: buffer to return value in * @buflen: buffer length * * The difference from d_path() is that this prepends "(unreachable)" * to paths which are unreachable from the current process' root. */ char *d_path_with_unreachable(const struct path *path, char *buf, int buflen) { char *res = buf + buflen; struct path root; |
8df9d1a41 vfs: show unreach... |
2566 2567 2568 2569 2570 2571 |
int error; if (path->dentry->d_op && path->dentry->d_op->d_dname) return path->dentry->d_op->d_dname(path->dentry, buf, buflen); get_fs_root(current->fs, &root); |
949854d02 fs: Use rename lo... |
2572 |
write_seqlock(&rename_lock); |
02125a826 fix apparmor dere... |
2573 2574 |
error = path_with_deleted(path, &root, &res, &buflen); if (error > 0) |
8df9d1a41 vfs: show unreach... |
2575 |
error = prepend_unreachable(&res, &buflen); |
949854d02 fs: Use rename lo... |
2576 |
write_sequnlock(&rename_lock); |
8df9d1a41 vfs: show unreach... |
2577 2578 2579 2580 2581 2582 |
path_put(&root); if (error) res = ERR_PTR(error); return res; } |
1da177e4c Linux-2.6.12-rc2 |
2583 |
/* |
c23fbb6bc VFS: delay the de... |
2584 2585 2586 2587 2588 2589 2590 2591 2592 2593 2594 2595 2596 2597 2598 2599 2600 2601 2602 2603 2604 |
* Helper function for dentry_operations.d_dname() members */ char *dynamic_dname(struct dentry *dentry, char *buffer, int buflen, const char *fmt, ...) { va_list args; char temp[64]; int sz; va_start(args, fmt); sz = vsnprintf(temp, sizeof(temp), fmt, args) + 1; va_end(args); if (sz > sizeof(temp) || sz > buflen) return ERR_PTR(-ENAMETOOLONG); buffer += buflen - sz; return memcpy(buffer, temp, sz); } /* |
6092d0481 [patch 1/7] vfs: ... |
2605 2606 |
* Write full pathname from the root of the filesystem into the buffer. */ |
ec2447c27 hostfs: simplify ... |
2607 |
static char *__dentry_path(struct dentry *dentry, char *buf, int buflen) |
6092d0481 [patch 1/7] vfs: ... |
2608 2609 2610 |
{ char *end = buf + buflen; char *retval; |
6092d0481 [patch 1/7] vfs: ... |
2611 |
prepend(&end, &buflen, "\0", 1); |
6092d0481 [patch 1/7] vfs: ... |
2612 2613 2614 2615 2616 |
if (buflen < 1) goto Elong; /* Get '/' right */ retval = end-1; *retval = '/'; |
cdd16d026 [patch 2/3] vfs: ... |
2617 2618 |
while (!IS_ROOT(dentry)) { struct dentry *parent = dentry->d_parent; |
9abca3608 fs: increase d_na... |
2619 |
int error; |
6092d0481 [patch 1/7] vfs: ... |
2620 |
|
6092d0481 [patch 1/7] vfs: ... |
2621 |
prefetch(parent); |
9abca3608 fs: increase d_na... |
2622 2623 2624 2625 |
spin_lock(&dentry->d_lock); error = prepend_name(&end, &buflen, &dentry->d_name); spin_unlock(&dentry->d_lock); if (error != 0 || prepend(&end, &buflen, "/", 1) != 0) |
6092d0481 [patch 1/7] vfs: ... |
2626 2627 2628 2629 2630 |
goto Elong; retval = end; dentry = parent; } |
c103135c1 new helper: __den... |
2631 2632 2633 2634 |
return retval; Elong: return ERR_PTR(-ENAMETOOLONG); } |
ec2447c27 hostfs: simplify ... |
2635 2636 2637 2638 |
char *dentry_path_raw(struct dentry *dentry, char *buf, int buflen) { char *retval; |
949854d02 fs: Use rename lo... |
2639 |
write_seqlock(&rename_lock); |
ec2447c27 hostfs: simplify ... |
2640 |
retval = __dentry_path(dentry, buf, buflen); |
949854d02 fs: Use rename lo... |
2641 |
write_sequnlock(&rename_lock); |
ec2447c27 hostfs: simplify ... |
2642 2643 2644 2645 |
return retval; } EXPORT_SYMBOL(dentry_path_raw); |
c103135c1 new helper: __den... |
2646 2647 2648 2649 2650 |
char *dentry_path(struct dentry *dentry, char *buf, int buflen) { char *p = NULL; char *retval; |
949854d02 fs: Use rename lo... |
2651 |
write_seqlock(&rename_lock); |
c103135c1 new helper: __den... |
2652 2653 2654 2655 2656 2657 2658 |
if (d_unlinked(dentry)) { p = buf + buflen; if (prepend(&p, &buflen, "//deleted", 10) != 0) goto Elong; buflen++; } retval = __dentry_path(dentry, buf, buflen); |
949854d02 fs: Use rename lo... |
2659 |
write_sequnlock(&rename_lock); |
c103135c1 new helper: __den... |
2660 2661 |
if (!IS_ERR(retval) && p) *p = '/'; /* restore '/' overriden with '\0' */ |
6092d0481 [patch 1/7] vfs: ... |
2662 2663 |
return retval; Elong: |
6092d0481 [patch 1/7] vfs: ... |
2664 2665 2666 2667 |
return ERR_PTR(-ENAMETOOLONG); } /* |
1da177e4c Linux-2.6.12-rc2 |
2668 2669 2670 2671 2672 2673 2674 2675 2676 2677 2678 2679 2680 2681 2682 2683 2684 |
* NOTE! The user-level library version returns a * character pointer. The kernel system call just * returns the length of the buffer filled (which * includes the ending '\0' character), or a negative * error value. So libc would do something like * * char *getcwd(char * buf, size_t size) * { * int retval; * * retval = sys_getcwd(buf, size); * if (retval >= 0) * return buf; * errno = -retval; * return NULL; * } */ |
3cdad4288 [CVE-2009-0029] S... |
2685 |
SYSCALL_DEFINE2(getcwd, char __user *, buf, unsigned long, size) |
1da177e4c Linux-2.6.12-rc2 |
2686 |
{ |
552ce544e Revert "[PATCH] F... |
2687 |
int error; |
6ac08c39a Use struct path i... |
2688 |
struct path pwd, root; |
552ce544e Revert "[PATCH] F... |
2689 |
char *page = (char *) __get_free_page(GFP_USER); |
1da177e4c Linux-2.6.12-rc2 |
2690 2691 2692 |
if (!page) return -ENOMEM; |
f7ad3c6be vfs: add helpers ... |
2693 |
get_fs_root_and_pwd(current->fs, &root, &pwd); |
1da177e4c Linux-2.6.12-rc2 |
2694 |
|
552ce544e Revert "[PATCH] F... |
2695 |
error = -ENOENT; |
949854d02 fs: Use rename lo... |
2696 |
write_seqlock(&rename_lock); |
f3da392e9 dcache: extrace a... |
2697 |
if (!d_unlinked(pwd.dentry)) { |
552ce544e Revert "[PATCH] F... |
2698 |
unsigned long len; |
8df9d1a41 vfs: show unreach... |
2699 2700 |
char *cwd = page + PAGE_SIZE; int buflen = PAGE_SIZE; |
1da177e4c Linux-2.6.12-rc2 |
2701 |
|
8df9d1a41 vfs: show unreach... |
2702 |
prepend(&cwd, &buflen, "\0", 1); |
02125a826 fix apparmor dere... |
2703 |
error = prepend_path(&pwd, &root, &cwd, &buflen); |
949854d02 fs: Use rename lo... |
2704 |
write_sequnlock(&rename_lock); |
552ce544e Revert "[PATCH] F... |
2705 |
|
02125a826 fix apparmor dere... |
2706 |
if (error < 0) |
552ce544e Revert "[PATCH] F... |
2707 |
goto out; |
8df9d1a41 vfs: show unreach... |
2708 |
/* Unreachable from current root */ |
02125a826 fix apparmor dere... |
2709 |
if (error > 0) { |
8df9d1a41 vfs: show unreach... |
2710 2711 2712 2713 |
error = prepend_unreachable(&cwd, &buflen); if (error) goto out; } |
552ce544e Revert "[PATCH] F... |
2714 2715 2716 2717 2718 2719 2720 |
error = -ERANGE; len = PAGE_SIZE + page - cwd; if (len <= size) { error = len; if (copy_to_user(buf, cwd, len)) error = -EFAULT; } |
949854d02 fs: Use rename lo... |
2721 2722 |
} else { write_sequnlock(&rename_lock); |
949854d02 fs: Use rename lo... |
2723 |
} |
1da177e4c Linux-2.6.12-rc2 |
2724 2725 |
out: |
6ac08c39a Use struct path i... |
2726 2727 |
path_put(&pwd); path_put(&root); |
1da177e4c Linux-2.6.12-rc2 |
2728 2729 2730 2731 2732 2733 2734 2735 2736 2737 2738 2739 2740 2741 2742 2743 2744 2745 2746 2747 |
free_page((unsigned long) page); return error; } /* * Test whether new_dentry is a subdirectory of old_dentry. * * Trivially implemented using the dcache structure */ /** * is_subdir - is new dentry a subdirectory of old_dentry * @new_dentry: new dentry * @old_dentry: old dentry * * Returns 1 if new_dentry is a subdirectory of the parent (at any depth). * Returns 0 otherwise. * Caller must ensure that "new_dentry" is pinned before calling is_subdir() */ |
e2761a116 [PATCH vfs-2.6 2/... |
2748 |
int is_subdir(struct dentry *new_dentry, struct dentry *old_dentry) |
1da177e4c Linux-2.6.12-rc2 |
2749 2750 |
{ int result; |
949854d02 fs: Use rename lo... |
2751 |
unsigned seq; |
1da177e4c Linux-2.6.12-rc2 |
2752 |
|
e2761a116 [PATCH vfs-2.6 2/... |
2753 2754 |
if (new_dentry == old_dentry) return 1; |
e2761a116 [PATCH vfs-2.6 2/... |
2755 |
do { |
1da177e4c Linux-2.6.12-rc2 |
2756 |
/* for restarting inner loop in case of seq retry */ |
1da177e4c Linux-2.6.12-rc2 |
2757 |
seq = read_seqbegin(&rename_lock); |
949854d02 fs: Use rename lo... |
2758 2759 2760 2761 2762 |
/* * Need rcu_readlock to protect against the d_parent trashing * due to d_move */ rcu_read_lock(); |
e2761a116 [PATCH vfs-2.6 2/... |
2763 |
if (d_ancestor(old_dentry, new_dentry)) |
1da177e4c Linux-2.6.12-rc2 |
2764 |
result = 1; |
e2761a116 [PATCH vfs-2.6 2/... |
2765 2766 |
else result = 0; |
949854d02 fs: Use rename lo... |
2767 |
rcu_read_unlock(); |
1da177e4c Linux-2.6.12-rc2 |
2768 |
} while (read_seqretry(&rename_lock, seq)); |
1da177e4c Linux-2.6.12-rc2 |
2769 2770 2771 2772 2773 2774 |
return result; } void d_genocide(struct dentry *root) { |
949854d02 fs: Use rename lo... |
2775 |
struct dentry *this_parent; |
1da177e4c Linux-2.6.12-rc2 |
2776 |
struct list_head *next; |
949854d02 fs: Use rename lo... |
2777 |
unsigned seq; |
58db63d08 fs: dcache avoid ... |
2778 |
int locked = 0; |
1da177e4c Linux-2.6.12-rc2 |
2779 |
|
949854d02 fs: Use rename lo... |
2780 |
seq = read_seqbegin(&rename_lock); |
58db63d08 fs: dcache avoid ... |
2781 2782 |
again: this_parent = root; |
2fd6b7f50 fs: dcache scale ... |
2783 |
spin_lock(&this_parent->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
2784 2785 2786 2787 2788 |
repeat: next = this_parent->d_subdirs.next; resume: while (next != &this_parent->d_subdirs) { struct list_head *tmp = next; |
5160ee6fc [PATCH] shrink de... |
2789 |
struct dentry *dentry = list_entry(tmp, struct dentry, d_u.d_child); |
1da177e4c Linux-2.6.12-rc2 |
2790 |
next = tmp->next; |
949854d02 fs: Use rename lo... |
2791 |
|
da5029563 fs: dcache scale ... |
2792 2793 2794 |
spin_lock_nested(&dentry->d_lock, DENTRY_D_LOCK_NESTED); if (d_unhashed(dentry) || !dentry->d_inode) { spin_unlock(&dentry->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
2795 |
continue; |
da5029563 fs: dcache scale ... |
2796 |
} |
1da177e4c Linux-2.6.12-rc2 |
2797 |
if (!list_empty(&dentry->d_subdirs)) { |
2fd6b7f50 fs: dcache scale ... |
2798 2799 |
spin_unlock(&this_parent->d_lock); spin_release(&dentry->d_lock.dep_map, 1, _RET_IP_); |
1da177e4c Linux-2.6.12-rc2 |
2800 |
this_parent = dentry; |
2fd6b7f50 fs: dcache scale ... |
2801 |
spin_acquire(&this_parent->d_lock.dep_map, 0, 1, _RET_IP_); |
1da177e4c Linux-2.6.12-rc2 |
2802 2803 |
goto repeat; } |
949854d02 fs: Use rename lo... |
2804 2805 2806 2807 |
if (!(dentry->d_flags & DCACHE_GENOCIDE)) { dentry->d_flags |= DCACHE_GENOCIDE; dentry->d_count--; } |
b7ab39f63 fs: dcache scale ... |
2808 |
spin_unlock(&dentry->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
2809 2810 |
} if (this_parent != root) { |
c826cb7df dcache.c: create ... |
2811 |
struct dentry *child = this_parent; |
949854d02 fs: Use rename lo... |
2812 2813 2814 2815 |
if (!(this_parent->d_flags & DCACHE_GENOCIDE)) { this_parent->d_flags |= DCACHE_GENOCIDE; this_parent->d_count--; } |
c826cb7df dcache.c: create ... |
2816 2817 |
this_parent = try_to_ascend(this_parent, locked, seq); if (!this_parent) |
949854d02 fs: Use rename lo... |
2818 |
goto rename_retry; |
949854d02 fs: Use rename lo... |
2819 |
next = child->d_u.d_child.next; |
1da177e4c Linux-2.6.12-rc2 |
2820 2821 |
goto resume; } |
2fd6b7f50 fs: dcache scale ... |
2822 |
spin_unlock(&this_parent->d_lock); |
58db63d08 fs: dcache avoid ... |
2823 |
if (!locked && read_seqretry(&rename_lock, seq)) |
949854d02 fs: Use rename lo... |
2824 |
goto rename_retry; |
58db63d08 fs: dcache avoid ... |
2825 2826 2827 2828 2829 2830 2831 2832 |
if (locked) write_sequnlock(&rename_lock); return; rename_retry: locked = 1; write_seqlock(&rename_lock); goto again; |
1da177e4c Linux-2.6.12-rc2 |
2833 2834 2835 2836 2837 2838 2839 2840 2841 2842 2843 2844 2845 2846 2847 2848 2849 2850 2851 2852 |
} /** * find_inode_number - check for dentry with name * @dir: directory to check * @name: Name to find. * * Check whether a dentry already exists for the given name, * and return the inode number if it has an inode. Otherwise * 0 is returned. * * This routine is used to post-process directory listings for * filesystems using synthetic inode numbers, and is necessary * to keep getcwd() working. */ ino_t find_inode_number(struct dentry *dir, struct qstr *name) { struct dentry * dentry; ino_t ino = 0; |
3e7e241f8 [PATCH] dcache: A... |
2853 2854 |
dentry = d_hash_and_lookup(dir, name); if (dentry) { |
1da177e4c Linux-2.6.12-rc2 |
2855 2856 2857 2858 |
if (dentry->d_inode) ino = dentry->d_inode->i_ino; dput(dentry); } |
1da177e4c Linux-2.6.12-rc2 |
2859 2860 |
return ino; } |
ec4f86059 fs/dcache.c: Codi... |
2861 |
EXPORT_SYMBOL(find_inode_number); |
1da177e4c Linux-2.6.12-rc2 |
2862 2863 2864 2865 2866 2867 2868 2869 2870 2871 2872 2873 2874 2875 2876 2877 2878 2879 2880 2881 2882 2883 2884 |
static __initdata unsigned long dhash_entries; static int __init set_dhash_entries(char *str) { if (!str) return 0; dhash_entries = simple_strtoul(str, &str, 0); return 1; } __setup("dhash_entries=", set_dhash_entries); static void __init dcache_init_early(void) { int loop; /* If hashes are distributed across NUMA nodes, defer * hash allocation until vmalloc space is available. */ if (hashdist) return; dentry_hashtable = alloc_large_system_hash("Dentry cache", |
b07ad9967 vfs: get rid of '... |
2885 |
sizeof(struct hlist_bl_head), |
1da177e4c Linux-2.6.12-rc2 |
2886 2887 2888 2889 2890 2891 2892 2893 |
dhash_entries, 13, HASH_EARLY, &d_hash_shift, &d_hash_mask, 0); for (loop = 0; loop < (1 << d_hash_shift); loop++) |
b07ad9967 vfs: get rid of '... |
2894 |
INIT_HLIST_BL_HEAD(dentry_hashtable + loop); |
1da177e4c Linux-2.6.12-rc2 |
2895 |
} |
74bf17cff fs: remove the un... |
2896 |
static void __init dcache_init(void) |
1da177e4c Linux-2.6.12-rc2 |
2897 2898 2899 2900 2901 2902 2903 2904 |
{ int loop; /* * A constructor could be added for stable state like the lists, * but it is probably not worth it because of the cache nature * of the dcache. */ |
0a31bd5f2 KMEM_CACHE(): sim... |
2905 2906 |
dentry_cache = KMEM_CACHE(dentry, SLAB_RECLAIM_ACCOUNT|SLAB_PANIC|SLAB_MEM_SPREAD); |
1da177e4c Linux-2.6.12-rc2 |
2907 2908 2909 2910 2911 2912 2913 |
/* Hash may have been set up in dcache_init_early */ if (!hashdist) return; dentry_hashtable = alloc_large_system_hash("Dentry cache", |
b07ad9967 vfs: get rid of '... |
2914 |
sizeof(struct hlist_bl_head), |
1da177e4c Linux-2.6.12-rc2 |
2915 2916 2917 2918 2919 2920 2921 2922 |
dhash_entries, 13, 0, &d_hash_shift, &d_hash_mask, 0); for (loop = 0; loop < (1 << d_hash_shift); loop++) |
b07ad9967 vfs: get rid of '... |
2923 |
INIT_HLIST_BL_HEAD(dentry_hashtable + loop); |
1da177e4c Linux-2.6.12-rc2 |
2924 2925 2926 |
} /* SLAB cache for __getname() consumers */ |
e18b890bb [PATCH] slab: rem... |
2927 |
struct kmem_cache *names_cachep __read_mostly; |
ec4f86059 fs/dcache.c: Codi... |
2928 |
EXPORT_SYMBOL(names_cachep); |
1da177e4c Linux-2.6.12-rc2 |
2929 |
|
1da177e4c Linux-2.6.12-rc2 |
2930 |
EXPORT_SYMBOL(d_genocide); |
1da177e4c Linux-2.6.12-rc2 |
2931 2932 2933 2934 2935 2936 2937 2938 2939 2940 2941 2942 2943 2944 2945 2946 2947 |
void __init vfs_caches_init_early(void) { dcache_init_early(); inode_init_early(); } void __init vfs_caches_init(unsigned long mempages) { unsigned long reserve; /* Base hash sizes on available memory, with a reserve equal to 150% of current kernel size */ reserve = min((mempages - nr_free_pages()) * 3/2, mempages - 1); mempages -= reserve; names_cachep = kmem_cache_create("names_cache", PATH_MAX, 0, |
20c2df83d mm: Remove slab d... |
2948 |
SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL); |
1da177e4c Linux-2.6.12-rc2 |
2949 |
|
74bf17cff fs: remove the un... |
2950 2951 |
dcache_init(); inode_init(); |
1da177e4c Linux-2.6.12-rc2 |
2952 |
files_init(mempages); |
74bf17cff fs: remove the un... |
2953 |
mnt_init(); |
1da177e4c Linux-2.6.12-rc2 |
2954 2955 2956 |
bdev_cache_init(); chrdev_init(); } |