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fs/dcache.c
76.7 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 "internal.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); 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_tail(struct dentry *dentry) |
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{ |
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spin_lock(&dcache_lru_lock); |
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if (list_empty(&dentry->d_lru)) { list_add_tail(&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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} else { list_move_tail(&dentry->d_lru, &dentry->d_sb->s_dentry_lru); |
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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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spin_unlock(&dentry->d_lock); |
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return; } |
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if (dentry->d_flags & DCACHE_OP_DELETE) { |
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if (dentry->d_op->d_delete(dentry)) |
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goto kill_it; |
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} |
265ac9023 fs: improve DCACH... |
461 |
|
1da177e4c Linux-2.6.12-rc2 |
462 463 464 |
/* Unreachable? Get rid of it */ if (d_unhashed(dentry)) goto kill_it; |
265ac9023 fs: improve DCACH... |
465 |
|
44396f4b5 fs: add a DCACHE_... |
466 467 468 469 470 471 472 |
/* * 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... |
473 |
dentry_lru_add(dentry); |
265ac9023 fs: improve DCACH... |
474 |
|
61f3dee4a fs: dcache reduce... |
475 476 |
dentry->d_count--; spin_unlock(&dentry->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
477 |
return; |
d52b90864 fix quadratic beh... |
478 |
kill_it: |
77812a1ef fs: consolidate d... |
479 |
dentry = dentry_kill(dentry, 1); |
d52b90864 fix quadratic beh... |
480 481 |
if (dentry) goto repeat; |
1da177e4c Linux-2.6.12-rc2 |
482 |
} |
ec4f86059 fs/dcache.c: Codi... |
483 |
EXPORT_SYMBOL(dput); |
1da177e4c Linux-2.6.12-rc2 |
484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 |
/** * 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 ... |
502 |
spin_lock(&dentry->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
503 |
if (d_unhashed(dentry)) { |
da5029563 fs: dcache scale ... |
504 |
spin_unlock(&dentry->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
505 506 507 508 509 510 511 |
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 ... |
512 |
spin_unlock(&dentry->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
513 |
shrink_dcache_parent(dentry); |
da5029563 fs: dcache scale ... |
514 |
spin_lock(&dentry->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
515 516 517 518 519 520 521 522 523 524 525 |
} /* * 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... |
526 527 |
* We also need to leave mountpoints alone, * directory or not. |
1da177e4c Linux-2.6.12-rc2 |
528 |
*/ |
50e696308 vfs: d_invalidate... |
529 530 |
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 |
531 |
spin_unlock(&dentry->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
532 533 534 535 536 537 |
return -EBUSY; } } __d_drop(dentry); spin_unlock(&dentry->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
538 539 |
return 0; } |
ec4f86059 fs/dcache.c: Codi... |
540 |
EXPORT_SYMBOL(d_invalidate); |
1da177e4c Linux-2.6.12-rc2 |
541 |
|
b5c84bf6f fs: dcache remove... |
542 |
/* This must be called with d_lock held */ |
dc0474be3 fs: dcache ration... |
543 |
static inline void __dget_dlock(struct dentry *dentry) |
230445078 fs: dcache scale lru |
544 |
{ |
b7ab39f63 fs: dcache scale ... |
545 |
dentry->d_count++; |
230445078 fs: dcache scale lru |
546 |
} |
dc0474be3 fs: dcache ration... |
547 |
static inline void __dget(struct dentry *dentry) |
1da177e4c Linux-2.6.12-rc2 |
548 |
{ |
230445078 fs: dcache scale lru |
549 |
spin_lock(&dentry->d_lock); |
dc0474be3 fs: dcache ration... |
550 |
__dget_dlock(dentry); |
230445078 fs: dcache scale lru |
551 |
spin_unlock(&dentry->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
552 |
} |
b7ab39f63 fs: dcache scale ... |
553 554 555 556 557 |
struct dentry *dget_parent(struct dentry *dentry) { struct dentry *ret; repeat: |
a734eb458 fs: dcache reduce... |
558 559 560 561 562 |
/* * Don't need rcu_dereference because we re-check it was correct under * the lock. */ rcu_read_lock(); |
b7ab39f63 fs: dcache scale ... |
563 |
ret = dentry->d_parent; |
a734eb458 fs: dcache reduce... |
564 565 566 567 |
spin_lock(&ret->d_lock); if (unlikely(ret != dentry->d_parent)) { spin_unlock(&ret->d_lock); rcu_read_unlock(); |
b7ab39f63 fs: dcache scale ... |
568 569 |
goto repeat; } |
a734eb458 fs: dcache reduce... |
570 |
rcu_read_unlock(); |
b7ab39f63 fs: dcache scale ... |
571 572 573 |
BUG_ON(!ret->d_count); ret->d_count++; spin_unlock(&ret->d_lock); |
b7ab39f63 fs: dcache scale ... |
574 575 576 |
return ret; } EXPORT_SYMBOL(dget_parent); |
1da177e4c Linux-2.6.12-rc2 |
577 578 579 580 581 582 583 584 585 586 587 588 |
/** * 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... |
589 |
* If the inode has an IS_ROOT, DCACHE_DISCONNECTED alias, then prefer |
1da177e4c Linux-2.6.12-rc2 |
590 |
* any other hashed alias over that one unless @want_discon is set, |
21c0d8fdd [PATCH] knfsd: cl... |
591 |
* in which case only return an IS_ROOT, DCACHE_DISCONNECTED alias. |
1da177e4c Linux-2.6.12-rc2 |
592 |
*/ |
da5029563 fs: dcache scale ... |
593 |
static struct dentry *__d_find_alias(struct inode *inode, int want_discon) |
1da177e4c Linux-2.6.12-rc2 |
594 |
{ |
da5029563 fs: dcache scale ... |
595 |
struct dentry *alias, *discon_alias; |
1da177e4c Linux-2.6.12-rc2 |
596 |
|
da5029563 fs: dcache scale ... |
597 598 599 600 |
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 |
601 |
if (S_ISDIR(inode->i_mode) || !d_unhashed(alias)) { |
21c0d8fdd [PATCH] knfsd: cl... |
602 |
if (IS_ROOT(alias) && |
da5029563 fs: dcache scale ... |
603 |
(alias->d_flags & DCACHE_DISCONNECTED)) { |
1da177e4c Linux-2.6.12-rc2 |
604 |
discon_alias = alias; |
da5029563 fs: dcache scale ... |
605 |
} else if (!want_discon) { |
dc0474be3 fs: dcache ration... |
606 |
__dget_dlock(alias); |
da5029563 fs: dcache scale ... |
607 608 609 610 611 612 613 614 615 616 617 618 |
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... |
619 |
__dget_dlock(alias); |
da5029563 fs: dcache scale ... |
620 |
spin_unlock(&alias->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
621 622 623 |
return alias; } } |
da5029563 fs: dcache scale ... |
624 625 |
spin_unlock(&alias->d_lock); goto again; |
1da177e4c Linux-2.6.12-rc2 |
626 |
} |
da5029563 fs: dcache scale ... |
627 |
return NULL; |
1da177e4c Linux-2.6.12-rc2 |
628 |
} |
da5029563 fs: dcache scale ... |
629 |
struct dentry *d_find_alias(struct inode *inode) |
1da177e4c Linux-2.6.12-rc2 |
630 |
{ |
214fda1f6 [PATCH] Optimise ... |
631 632 633 |
struct dentry *de = NULL; if (!list_empty(&inode->i_dentry)) { |
873feea09 fs: dcache per-in... |
634 |
spin_lock(&inode->i_lock); |
214fda1f6 [PATCH] Optimise ... |
635 |
de = __d_find_alias(inode, 0); |
873feea09 fs: dcache per-in... |
636 |
spin_unlock(&inode->i_lock); |
214fda1f6 [PATCH] Optimise ... |
637 |
} |
1da177e4c Linux-2.6.12-rc2 |
638 639 |
return de; } |
ec4f86059 fs/dcache.c: Codi... |
640 |
EXPORT_SYMBOL(d_find_alias); |
1da177e4c Linux-2.6.12-rc2 |
641 642 643 644 645 646 647 |
/* * 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: ... |
648 |
struct dentry *dentry; |
1da177e4c Linux-2.6.12-rc2 |
649 |
restart: |
873feea09 fs: dcache per-in... |
650 |
spin_lock(&inode->i_lock); |
0cdca3f98 [PATCH] janitor: ... |
651 |
list_for_each_entry(dentry, &inode->i_dentry, d_alias) { |
1da177e4c Linux-2.6.12-rc2 |
652 |
spin_lock(&dentry->d_lock); |
b7ab39f63 fs: dcache scale ... |
653 |
if (!dentry->d_count) { |
dc0474be3 fs: dcache ration... |
654 |
__dget_dlock(dentry); |
1da177e4c Linux-2.6.12-rc2 |
655 656 |
__d_drop(dentry); spin_unlock(&dentry->d_lock); |
873feea09 fs: dcache per-in... |
657 |
spin_unlock(&inode->i_lock); |
1da177e4c Linux-2.6.12-rc2 |
658 659 660 661 662 |
dput(dentry); goto restart; } spin_unlock(&dentry->d_lock); } |
873feea09 fs: dcache per-in... |
663 |
spin_unlock(&inode->i_lock); |
1da177e4c Linux-2.6.12-rc2 |
664 |
} |
ec4f86059 fs/dcache.c: Codi... |
665 |
EXPORT_SYMBOL(d_prune_aliases); |
1da177e4c Linux-2.6.12-rc2 |
666 667 |
/* |
77812a1ef fs: consolidate d... |
668 669 670 |
* 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... |
671 |
* |
77812a1ef fs: consolidate d... |
672 |
* This may fail if locks cannot be acquired no problem, just try again. |
1da177e4c Linux-2.6.12-rc2 |
673 |
*/ |
77812a1ef fs: consolidate d... |
674 |
static void try_prune_one_dentry(struct dentry *dentry) |
31f3e0b3a [patch 1/3] vfs: ... |
675 |
__releases(dentry->d_lock) |
1da177e4c Linux-2.6.12-rc2 |
676 |
{ |
77812a1ef fs: consolidate d... |
677 |
struct dentry *parent; |
d52b90864 fix quadratic beh... |
678 |
|
77812a1ef fs: consolidate d... |
679 |
parent = dentry_kill(dentry, 0); |
d52b90864 fix quadratic beh... |
680 |
/* |
77812a1ef fs: consolidate d... |
681 682 683 684 685 686 687 688 |
* 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... |
689 |
*/ |
77812a1ef fs: consolidate d... |
690 691 692 693 694 695 696 |
if (!parent) return; if (parent == dentry) return; /* Prune ancestors. */ dentry = parent; |
d52b90864 fix quadratic beh... |
697 |
while (dentry) { |
b7ab39f63 fs: dcache scale ... |
698 |
spin_lock(&dentry->d_lock); |
89e605483 fs: dcache reduce... |
699 700 701 702 703 |
if (dentry->d_count > 1) { dentry->d_count--; spin_unlock(&dentry->d_lock); return; } |
77812a1ef fs: consolidate d... |
704 |
dentry = dentry_kill(dentry, 1); |
d52b90864 fix quadratic beh... |
705 |
} |
1da177e4c Linux-2.6.12-rc2 |
706 |
} |
3049cfe24 fs: split __shrin... |
707 |
static void shrink_dentry_list(struct list_head *list) |
1da177e4c Linux-2.6.12-rc2 |
708 |
{ |
da3bbdd46 fix soft lock up ... |
709 |
struct dentry *dentry; |
da3bbdd46 fix soft lock up ... |
710 |
|
ec33679d7 fs: use RCU in sh... |
711 712 |
rcu_read_lock(); for (;;) { |
ec33679d7 fs: use RCU in sh... |
713 714 715 716 717 718 |
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 |
719 720 |
continue; } |
1da177e4c Linux-2.6.12-rc2 |
721 722 |
/* * We found an inuse dentry which was not removed from |
da3bbdd46 fix soft lock up ... |
723 724 |
* the LRU because of laziness during lookup. Do not free * it - just keep it off the LRU list. |
1da177e4c Linux-2.6.12-rc2 |
725 |
*/ |
b7ab39f63 fs: dcache scale ... |
726 |
if (dentry->d_count) { |
ec33679d7 fs: use RCU in sh... |
727 |
dentry_lru_del(dentry); |
da3bbdd46 fix soft lock up ... |
728 |
spin_unlock(&dentry->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
729 730 |
continue; } |
ec33679d7 fs: use RCU in sh... |
731 |
|
ec33679d7 fs: use RCU in sh... |
732 |
rcu_read_unlock(); |
77812a1ef fs: consolidate d... |
733 734 |
try_prune_one_dentry(dentry); |
ec33679d7 fs: use RCU in sh... |
735 |
rcu_read_lock(); |
da3bbdd46 fix soft lock up ... |
736 |
} |
ec33679d7 fs: use RCU in sh... |
737 |
rcu_read_unlock(); |
3049cfe24 fs: split __shrin... |
738 739 740 741 742 743 744 745 746 747 |
} /** * __shrink_dcache_sb - shrink the dentry LRU on a given superblock * @sb: superblock to shrink dentry LRU. * @count: number of entries to prune * @flags: flags to control the dentry processing * * If flags contains DCACHE_REFERENCED reference dentries will not be pruned. */ |
b0d40c92a superblock: intro... |
748 |
static void __shrink_dcache_sb(struct super_block *sb, int count, int flags) |
3049cfe24 fs: split __shrin... |
749 |
{ |
3049cfe24 fs: split __shrin... |
750 751 752 |
struct dentry *dentry; LIST_HEAD(referenced); LIST_HEAD(tmp); |
3049cfe24 fs: split __shrin... |
753 |
|
230445078 fs: dcache scale lru |
754 755 |
relock: spin_lock(&dcache_lru_lock); |
3049cfe24 fs: split __shrin... |
756 757 758 759 |
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 |
760 761 762 763 764 |
if (!spin_trylock(&dentry->d_lock)) { spin_unlock(&dcache_lru_lock); cpu_relax(); goto relock; } |
3049cfe24 fs: split __shrin... |
765 766 767 768 769 |
/* * If we are honouring the DCACHE_REFERENCED flag and the * dentry has this flag set, don't free it. Clear the flag * and put it back on the LRU. */ |
230445078 fs: dcache scale lru |
770 771 772 773 |
if (flags & DCACHE_REFERENCED && dentry->d_flags & DCACHE_REFERENCED) { dentry->d_flags &= ~DCACHE_REFERENCED; list_move(&dentry->d_lru, &referenced); |
3049cfe24 fs: split __shrin... |
774 |
spin_unlock(&dentry->d_lock); |
230445078 fs: dcache scale lru |
775 776 777 |
} else { list_move_tail(&dentry->d_lru, &tmp); spin_unlock(&dentry->d_lock); |
b0d40c92a superblock: intro... |
778 |
if (!--count) |
230445078 fs: dcache scale lru |
779 |
break; |
3049cfe24 fs: split __shrin... |
780 |
} |
ec33679d7 fs: use RCU in sh... |
781 |
cond_resched_lock(&dcache_lru_lock); |
3049cfe24 fs: split __shrin... |
782 |
} |
da3bbdd46 fix soft lock up ... |
783 784 |
if (!list_empty(&referenced)) list_splice(&referenced, &sb->s_dentry_lru); |
230445078 fs: dcache scale lru |
785 |
spin_unlock(&dcache_lru_lock); |
ec33679d7 fs: use RCU in sh... |
786 787 |
shrink_dentry_list(&tmp); |
da3bbdd46 fix soft lock up ... |
788 789 790 |
} /** |
b0d40c92a superblock: intro... |
791 |
* prune_dcache_sb - shrink the dcache |
2af141626 fs/dcache.c: fix ... |
792 |
* @sb: superblock |
b0d40c92a superblock: intro... |
793 |
* @nr_to_scan: number of entries to try to free |
da3bbdd46 fix soft lock up ... |
794 |
* |
b0d40c92a superblock: intro... |
795 796 797 |
* Attempt to shrink the superblock dcache LRU by @nr_to_scan entries. This is * done when we need more memory an called from the superblock shrinker * function. |
da3bbdd46 fix soft lock up ... |
798 |
* |
b0d40c92a superblock: intro... |
799 800 |
* This function may fail to free any resources if all the dentries are in * use. |
da3bbdd46 fix soft lock up ... |
801 |
*/ |
b0d40c92a superblock: intro... |
802 |
void prune_dcache_sb(struct super_block *sb, int nr_to_scan) |
da3bbdd46 fix soft lock up ... |
803 |
{ |
b0d40c92a superblock: intro... |
804 |
__shrink_dcache_sb(sb, nr_to_scan, DCACHE_REFERENCED); |
1da177e4c Linux-2.6.12-rc2 |
805 |
} |
1da177e4c Linux-2.6.12-rc2 |
806 807 808 809 |
/** * shrink_dcache_sb - shrink dcache for a superblock * @sb: superblock * |
3049cfe24 fs: split __shrin... |
810 811 |
* 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 |
812 |
*/ |
3049cfe24 fs: split __shrin... |
813 |
void shrink_dcache_sb(struct super_block *sb) |
1da177e4c Linux-2.6.12-rc2 |
814 |
{ |
3049cfe24 fs: split __shrin... |
815 |
LIST_HEAD(tmp); |
230445078 fs: dcache scale lru |
816 |
spin_lock(&dcache_lru_lock); |
3049cfe24 fs: split __shrin... |
817 818 |
while (!list_empty(&sb->s_dentry_lru)) { list_splice_init(&sb->s_dentry_lru, &tmp); |
ec33679d7 fs: use RCU in sh... |
819 |
spin_unlock(&dcache_lru_lock); |
3049cfe24 fs: split __shrin... |
820 |
shrink_dentry_list(&tmp); |
ec33679d7 fs: use RCU in sh... |
821 |
spin_lock(&dcache_lru_lock); |
3049cfe24 fs: split __shrin... |
822 |
} |
230445078 fs: dcache scale lru |
823 |
spin_unlock(&dcache_lru_lock); |
1da177e4c Linux-2.6.12-rc2 |
824 |
} |
ec4f86059 fs/dcache.c: Codi... |
825 |
EXPORT_SYMBOL(shrink_dcache_sb); |
1da177e4c Linux-2.6.12-rc2 |
826 827 |
/* |
c636ebdb1 [PATCH] VFS: Dest... |
828 829 830 831 832 833 834 835 836 |
* 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... |
837 838 |
for (;;) { /* descend to the first leaf in the current subtree */ |
43c1c9cd2 VFS: Reorganise s... |
839 |
while (!list_empty(&dentry->d_subdirs)) |
c636ebdb1 [PATCH] VFS: Dest... |
840 841 |
dentry = list_entry(dentry->d_subdirs.next, struct dentry, d_u.d_child); |
c636ebdb1 [PATCH] VFS: Dest... |
842 843 844 845 846 |
/* 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 ... |
847 848 849 850 851 852 |
/* * 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... |
853 |
__d_shrink(dentry); |
b7ab39f63 fs: dcache scale ... |
854 |
if (dentry->d_count != 0) { |
c636ebdb1 [PATCH] VFS: Dest... |
855 856 857 858 859 860 861 862 863 |
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 ... |
864 |
dentry->d_count, |
c636ebdb1 [PATCH] VFS: Dest... |
865 866 867 868 |
dentry->d_sb->s_type->name, dentry->d_sb->s_id); BUG(); } |
2fd6b7f50 fs: dcache scale ... |
869 |
if (IS_ROOT(dentry)) { |
c636ebdb1 [PATCH] VFS: Dest... |
870 |
parent = NULL; |
2fd6b7f50 fs: dcache scale ... |
871 872 |
list_del(&dentry->d_u.d_child); } else { |
871c0067d [PATCH vfs-2.6 1/... |
873 |
parent = dentry->d_parent; |
b7ab39f63 fs: dcache scale ... |
874 |
parent->d_count--; |
2fd6b7f50 fs: dcache scale ... |
875 |
list_del(&dentry->d_u.d_child); |
871c0067d [PATCH vfs-2.6 1/... |
876 |
} |
c636ebdb1 [PATCH] VFS: Dest... |
877 |
|
c636ebdb1 [PATCH] VFS: Dest... |
878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 |
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... |
894 |
return; |
c636ebdb1 [PATCH] VFS: Dest... |
895 |
dentry = parent; |
c636ebdb1 [PATCH] VFS: Dest... |
896 897 898 899 900 901 902 903 904 |
} 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... |
905 |
* - we don't need to use dentry->d_lock because: |
c636ebdb1 [PATCH] VFS: Dest... |
906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 |
* - 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 ... |
922 |
dentry->d_count--; |
c636ebdb1 [PATCH] VFS: Dest... |
923 |
shrink_dcache_for_umount_subtree(dentry); |
ceb5bdc2d fs: dcache per-bu... |
924 925 |
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... |
926 927 928 929 930 |
shrink_dcache_for_umount_subtree(dentry); } } /* |
c826cb7df dcache.c: create ... |
931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 |
* 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 ... |
949 |
(old->d_flags & DCACHE_DISCONNECTED) || |
c826cb7df dcache.c: create ... |
950 951 952 953 954 955 956 957 958 959 |
(!locked && read_seqretry(&rename_lock, seq))) { spin_unlock(&new->d_lock); new = NULL; } rcu_read_unlock(); return new; } /* |
1da177e4c Linux-2.6.12-rc2 |
960 961 962 963 964 965 966 967 968 969 970 971 |
* 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 |
972 973 |
int have_submounts(struct dentry *parent) { |
949854d02 fs: Use rename lo... |
974 |
struct dentry *this_parent; |
1da177e4c Linux-2.6.12-rc2 |
975 |
struct list_head *next; |
949854d02 fs: Use rename lo... |
976 |
unsigned seq; |
58db63d08 fs: dcache avoid ... |
977 |
int locked = 0; |
949854d02 fs: Use rename lo... |
978 |
|
949854d02 fs: Use rename lo... |
979 |
seq = read_seqbegin(&rename_lock); |
58db63d08 fs: dcache avoid ... |
980 981 |
again: this_parent = parent; |
1da177e4c Linux-2.6.12-rc2 |
982 |
|
1da177e4c Linux-2.6.12-rc2 |
983 984 |
if (d_mountpoint(parent)) goto positive; |
2fd6b7f50 fs: dcache scale ... |
985 |
spin_lock(&this_parent->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
986 987 988 989 990 |
repeat: next = this_parent->d_subdirs.next; resume: while (next != &this_parent->d_subdirs) { struct list_head *tmp = next; |
5160ee6fc [PATCH] shrink de... |
991 |
struct dentry *dentry = list_entry(tmp, struct dentry, d_u.d_child); |
1da177e4c Linux-2.6.12-rc2 |
992 |
next = tmp->next; |
2fd6b7f50 fs: dcache scale ... |
993 994 |
spin_lock_nested(&dentry->d_lock, DENTRY_D_LOCK_NESTED); |
1da177e4c Linux-2.6.12-rc2 |
995 |
/* Have we found a mount point ? */ |
2fd6b7f50 fs: dcache scale ... |
996 997 998 |
if (d_mountpoint(dentry)) { spin_unlock(&dentry->d_lock); spin_unlock(&this_parent->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
999 |
goto positive; |
2fd6b7f50 fs: dcache scale ... |
1000 |
} |
1da177e4c Linux-2.6.12-rc2 |
1001 |
if (!list_empty(&dentry->d_subdirs)) { |
2fd6b7f50 fs: dcache scale ... |
1002 1003 |
spin_unlock(&this_parent->d_lock); spin_release(&dentry->d_lock.dep_map, 1, _RET_IP_); |
1da177e4c Linux-2.6.12-rc2 |
1004 |
this_parent = dentry; |
2fd6b7f50 fs: dcache scale ... |
1005 |
spin_acquire(&this_parent->d_lock.dep_map, 0, 1, _RET_IP_); |
1da177e4c Linux-2.6.12-rc2 |
1006 1007 |
goto repeat; } |
2fd6b7f50 fs: dcache scale ... |
1008 |
spin_unlock(&dentry->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
1009 1010 1011 1012 1013 |
} /* * All done at this level ... ascend and resume the search. */ if (this_parent != parent) { |
c826cb7df dcache.c: create ... |
1014 1015 1016 |
struct dentry *child = this_parent; this_parent = try_to_ascend(this_parent, locked, seq); if (!this_parent) |
949854d02 fs: Use rename lo... |
1017 |
goto rename_retry; |
949854d02 fs: Use rename lo... |
1018 |
next = child->d_u.d_child.next; |
1da177e4c Linux-2.6.12-rc2 |
1019 1020 |
goto resume; } |
2fd6b7f50 fs: dcache scale ... |
1021 |
spin_unlock(&this_parent->d_lock); |
58db63d08 fs: dcache avoid ... |
1022 |
if (!locked && read_seqretry(&rename_lock, seq)) |
949854d02 fs: Use rename lo... |
1023 |
goto rename_retry; |
58db63d08 fs: dcache avoid ... |
1024 1025 |
if (locked) write_sequnlock(&rename_lock); |
1da177e4c Linux-2.6.12-rc2 |
1026 1027 |
return 0; /* No mount points found in tree */ positive: |
58db63d08 fs: dcache avoid ... |
1028 |
if (!locked && read_seqretry(&rename_lock, seq)) |
949854d02 fs: Use rename lo... |
1029 |
goto rename_retry; |
58db63d08 fs: dcache avoid ... |
1030 1031 |
if (locked) write_sequnlock(&rename_lock); |
1da177e4c Linux-2.6.12-rc2 |
1032 |
return 1; |
58db63d08 fs: dcache avoid ... |
1033 1034 1035 1036 1037 |
rename_retry: locked = 1; write_seqlock(&rename_lock); goto again; |
1da177e4c Linux-2.6.12-rc2 |
1038 |
} |
ec4f86059 fs/dcache.c: Codi... |
1039 |
EXPORT_SYMBOL(have_submounts); |
1da177e4c Linux-2.6.12-rc2 |
1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 |
/* * 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. */ static int select_parent(struct dentry * parent) { |
949854d02 fs: Use rename lo... |
1057 |
struct dentry *this_parent; |
1da177e4c Linux-2.6.12-rc2 |
1058 |
struct list_head *next; |
949854d02 fs: Use rename lo... |
1059 |
unsigned seq; |
1da177e4c Linux-2.6.12-rc2 |
1060 |
int found = 0; |
58db63d08 fs: dcache avoid ... |
1061 |
int locked = 0; |
1da177e4c Linux-2.6.12-rc2 |
1062 |
|
949854d02 fs: Use rename lo... |
1063 |
seq = read_seqbegin(&rename_lock); |
58db63d08 fs: dcache avoid ... |
1064 1065 |
again: this_parent = parent; |
2fd6b7f50 fs: dcache scale ... |
1066 |
spin_lock(&this_parent->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
1067 1068 1069 1070 1071 |
repeat: next = this_parent->d_subdirs.next; resume: while (next != &this_parent->d_subdirs) { struct list_head *tmp = next; |
5160ee6fc [PATCH] shrink de... |
1072 |
struct dentry *dentry = list_entry(tmp, struct dentry, d_u.d_child); |
1da177e4c Linux-2.6.12-rc2 |
1073 |
next = tmp->next; |
2fd6b7f50 fs: dcache scale ... |
1074 |
spin_lock_nested(&dentry->d_lock, DENTRY_D_LOCK_NESTED); |
230445078 fs: dcache scale lru |
1075 |
|
1da177e4c Linux-2.6.12-rc2 |
1076 1077 1078 1079 |
/* * move only zero ref count dentries to the end * of the unused list for prune_dcache */ |
b7ab39f63 fs: dcache scale ... |
1080 |
if (!dentry->d_count) { |
a4633357a fs: clean up dent... |
1081 |
dentry_lru_move_tail(dentry); |
1da177e4c Linux-2.6.12-rc2 |
1082 |
found++; |
a4633357a fs: clean up dent... |
1083 1084 |
} else { dentry_lru_del(dentry); |
1da177e4c Linux-2.6.12-rc2 |
1085 1086 1087 1088 1089 1090 1091 |
} /* * 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 ... |
1092 1093 |
if (found && need_resched()) { spin_unlock(&dentry->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
1094 |
goto out; |
2fd6b7f50 fs: dcache scale ... |
1095 |
} |
1da177e4c Linux-2.6.12-rc2 |
1096 1097 1098 1099 1100 |
/* * Descend a level if the d_subdirs list is non-empty. */ if (!list_empty(&dentry->d_subdirs)) { |
2fd6b7f50 fs: dcache scale ... |
1101 1102 |
spin_unlock(&this_parent->d_lock); spin_release(&dentry->d_lock.dep_map, 1, _RET_IP_); |
1da177e4c Linux-2.6.12-rc2 |
1103 |
this_parent = dentry; |
2fd6b7f50 fs: dcache scale ... |
1104 |
spin_acquire(&this_parent->d_lock.dep_map, 0, 1, _RET_IP_); |
1da177e4c Linux-2.6.12-rc2 |
1105 1106 |
goto repeat; } |
2fd6b7f50 fs: dcache scale ... |
1107 1108 |
spin_unlock(&dentry->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
1109 1110 1111 1112 1113 |
} /* * All done at this level ... ascend and resume the search. */ if (this_parent != parent) { |
c826cb7df dcache.c: create ... |
1114 1115 1116 |
struct dentry *child = this_parent; this_parent = try_to_ascend(this_parent, locked, seq); if (!this_parent) |
949854d02 fs: Use rename lo... |
1117 |
goto rename_retry; |
949854d02 fs: Use rename lo... |
1118 |
next = child->d_u.d_child.next; |
1da177e4c Linux-2.6.12-rc2 |
1119 1120 1121 |
goto resume; } out: |
2fd6b7f50 fs: dcache scale ... |
1122 |
spin_unlock(&this_parent->d_lock); |
58db63d08 fs: dcache avoid ... |
1123 |
if (!locked && read_seqretry(&rename_lock, seq)) |
949854d02 fs: Use rename lo... |
1124 |
goto rename_retry; |
58db63d08 fs: dcache avoid ... |
1125 1126 |
if (locked) write_sequnlock(&rename_lock); |
1da177e4c Linux-2.6.12-rc2 |
1127 |
return found; |
58db63d08 fs: dcache avoid ... |
1128 1129 1130 1131 1132 1133 1134 |
rename_retry: if (found) return found; locked = 1; write_seqlock(&rename_lock); goto again; |
1da177e4c Linux-2.6.12-rc2 |
1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 |
} /** * shrink_dcache_parent - prune dcache * @parent: parent of entries to prune * * Prune the dcache to remove unused children of the parent dentry. */ void shrink_dcache_parent(struct dentry * parent) { |
da3bbdd46 fix soft lock up ... |
1146 |
struct super_block *sb = parent->d_sb; |
1da177e4c Linux-2.6.12-rc2 |
1147 1148 1149 |
int found; while ((found = select_parent(parent)) != 0) |
b0d40c92a superblock: intro... |
1150 |
__shrink_dcache_sb(sb, found, 0); |
1da177e4c Linux-2.6.12-rc2 |
1151 |
} |
ec4f86059 fs/dcache.c: Codi... |
1152 |
EXPORT_SYMBOL(shrink_dcache_parent); |
1da177e4c Linux-2.6.12-rc2 |
1153 |
|
1da177e4c Linux-2.6.12-rc2 |
1154 |
/** |
a4464dbc0 Make ->d_sb assig... |
1155 1156 |
* __d_alloc - allocate a dcache entry * @sb: filesystem it will belong to |
1da177e4c Linux-2.6.12-rc2 |
1157 1158 1159 1160 1161 1162 1163 |
* @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... |
1164 |
struct dentry *__d_alloc(struct super_block *sb, const struct qstr *name) |
1da177e4c Linux-2.6.12-rc2 |
1165 1166 1167 |
{ struct dentry *dentry; char *dname; |
e12ba74d8 Group short-lived... |
1168 |
dentry = kmem_cache_alloc(dentry_cache, GFP_KERNEL); |
1da177e4c Linux-2.6.12-rc2 |
1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 |
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 ... |
1187 |
dentry->d_count = 1; |
dea3667bc vfs: get rid of i... |
1188 |
dentry->d_flags = 0; |
1da177e4c Linux-2.6.12-rc2 |
1189 |
spin_lock_init(&dentry->d_lock); |
31e6b01f4 fs: rcu-walk for ... |
1190 |
seqcount_init(&dentry->d_seq); |
1da177e4c Linux-2.6.12-rc2 |
1191 |
dentry->d_inode = NULL; |
a4464dbc0 Make ->d_sb assig... |
1192 1193 |
dentry->d_parent = dentry; dentry->d_sb = sb; |
1da177e4c Linux-2.6.12-rc2 |
1194 1195 |
dentry->d_op = NULL; dentry->d_fsdata = NULL; |
ceb5bdc2d fs: dcache per-bu... |
1196 |
INIT_HLIST_BL_NODE(&dentry->d_hash); |
1da177e4c Linux-2.6.12-rc2 |
1197 1198 1199 |
INIT_LIST_HEAD(&dentry->d_lru); INIT_LIST_HEAD(&dentry->d_subdirs); INIT_LIST_HEAD(&dentry->d_alias); |
2fd6b7f50 fs: dcache scale ... |
1200 |
INIT_LIST_HEAD(&dentry->d_u.d_child); |
a4464dbc0 Make ->d_sb assig... |
1201 |
d_set_d_op(dentry, dentry->d_sb->s_d_op); |
1da177e4c Linux-2.6.12-rc2 |
1202 |
|
3e880fb5e fs: use fast coun... |
1203 |
this_cpu_inc(nr_dentry); |
312d3ca85 fs: use percpu co... |
1204 |
|
1da177e4c Linux-2.6.12-rc2 |
1205 1206 |
return dentry; } |
a4464dbc0 Make ->d_sb assig... |
1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 |
/** * 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... |
1235 |
EXPORT_SYMBOL(d_alloc); |
1da177e4c Linux-2.6.12-rc2 |
1236 |
|
4b936885a fs: improve scala... |
1237 1238 |
struct dentry *d_alloc_pseudo(struct super_block *sb, const struct qstr *name) { |
a4464dbc0 Make ->d_sb assig... |
1239 1240 |
struct dentry *dentry = __d_alloc(sb, name); if (dentry) |
4b936885a fs: improve scala... |
1241 |
dentry->d_flags |= DCACHE_DISCONNECTED; |
4b936885a fs: improve scala... |
1242 1243 1244 |
return dentry; } EXPORT_SYMBOL(d_alloc_pseudo); |
1da177e4c Linux-2.6.12-rc2 |
1245 1246 1247 1248 1249 1250 1251 1252 1253 |
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... |
1254 |
EXPORT_SYMBOL(d_alloc_name); |
1da177e4c Linux-2.6.12-rc2 |
1255 |
|
fb045adb9 fs: dcache reduce... |
1256 1257 |
void d_set_d_op(struct dentry *dentry, const struct dentry_operations *op) { |
6f7f7caab Turn d_set_d_op()... |
1258 1259 |
WARN_ON_ONCE(dentry->d_op); WARN_ON_ONCE(dentry->d_flags & (DCACHE_OP_HASH | |
fb045adb9 fs: dcache reduce... |
1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 |
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 ... |
1274 1275 |
if (op->d_prune) dentry->d_flags |= DCACHE_OP_PRUNE; |
fb045adb9 fs: dcache reduce... |
1276 1277 1278 |
} EXPORT_SYMBOL(d_set_d_op); |
360da9002 [PATCH vfs-2.6 3/... |
1279 1280 |
static void __d_instantiate(struct dentry *dentry, struct inode *inode) { |
b23fb0a60 fs: scale inode a... |
1281 |
spin_lock(&dentry->d_lock); |
9875cf806 Add a dentry op t... |
1282 1283 1284 |
if (inode) { if (unlikely(IS_AUTOMOUNT(inode))) dentry->d_flags |= DCACHE_NEED_AUTOMOUNT; |
360da9002 [PATCH vfs-2.6 3/... |
1285 |
list_add(&dentry->d_alias, &inode->i_dentry); |
9875cf806 Add a dentry op t... |
1286 |
} |
360da9002 [PATCH vfs-2.6 3/... |
1287 |
dentry->d_inode = inode; |
31e6b01f4 fs: rcu-walk for ... |
1288 |
dentry_rcuwalk_barrier(dentry); |
b23fb0a60 fs: scale inode a... |
1289 |
spin_unlock(&dentry->d_lock); |
360da9002 [PATCH vfs-2.6 3/... |
1290 1291 |
fsnotify_d_instantiate(dentry, inode); } |
1da177e4c Linux-2.6.12-rc2 |
1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 |
/** * 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... |
1309 |
BUG_ON(!list_empty(&entry->d_alias)); |
873feea09 fs: dcache per-in... |
1310 1311 |
if (inode) spin_lock(&inode->i_lock); |
360da9002 [PATCH vfs-2.6 3/... |
1312 |
__d_instantiate(entry, inode); |
873feea09 fs: dcache per-in... |
1313 1314 |
if (inode) spin_unlock(&inode->i_lock); |
1da177e4c Linux-2.6.12-rc2 |
1315 1316 |
security_d_instantiate(entry, inode); } |
ec4f86059 fs/dcache.c: Codi... |
1317 |
EXPORT_SYMBOL(d_instantiate); |
1da177e4c Linux-2.6.12-rc2 |
1318 1319 1320 1321 1322 1323 1324 1325 |
/** * 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... |
1326 |
* aliased dentry instead and drop one reference to inode. |
1da177e4c Linux-2.6.12-rc2 |
1327 1328 1329 |
* * Note that in order to avoid conflicts with rename() etc, the caller * had better be holding the parent directory semaphore. |
e866cfa93 [PATCH] d_instant... |
1330 1331 1332 1333 |
* * 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 |
1334 |
*/ |
770bfad84 NFS: Add dentry m... |
1335 1336 |
static struct dentry *__d_instantiate_unique(struct dentry *entry, struct inode *inode) |
1da177e4c Linux-2.6.12-rc2 |
1337 1338 1339 1340 1341 |
{ 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... |
1342 |
if (!inode) { |
360da9002 [PATCH vfs-2.6 3/... |
1343 |
__d_instantiate(entry, NULL); |
770bfad84 NFS: Add dentry m... |
1344 1345 |
return NULL; } |
1da177e4c Linux-2.6.12-rc2 |
1346 1347 |
list_for_each_entry(alias, &inode->i_dentry, d_alias) { struct qstr *qstr = &alias->d_name; |
9abca3608 fs: increase d_na... |
1348 1349 1350 1351 1352 |
/* * 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 |
1353 1354 1355 1356 |
if (qstr->hash != hash) continue; if (alias->d_parent != entry->d_parent) continue; |
9d55c369b fs: implement fas... |
1357 |
if (dentry_cmp(qstr->name, qstr->len, name, len)) |
1da177e4c Linux-2.6.12-rc2 |
1358 |
continue; |
dc0474be3 fs: dcache ration... |
1359 |
__dget(alias); |
1da177e4c Linux-2.6.12-rc2 |
1360 1361 |
return alias; } |
770bfad84 NFS: Add dentry m... |
1362 |
|
360da9002 [PATCH vfs-2.6 3/... |
1363 |
__d_instantiate(entry, inode); |
1da177e4c Linux-2.6.12-rc2 |
1364 1365 |
return NULL; } |
770bfad84 NFS: Add dentry m... |
1366 1367 1368 1369 1370 1371 |
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... |
1372 1373 |
if (inode) spin_lock(&inode->i_lock); |
770bfad84 NFS: Add dentry m... |
1374 |
result = __d_instantiate_unique(entry, inode); |
873feea09 fs: dcache per-in... |
1375 1376 |
if (inode) spin_unlock(&inode->i_lock); |
770bfad84 NFS: Add dentry m... |
1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 |
if (!result) { security_d_instantiate(entry, inode); return NULL; } BUG_ON(!d_unhashed(result)); iput(inode); return result; } |
1da177e4c Linux-2.6.12-rc2 |
1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 |
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... |
1404 1405 |
res = __d_alloc(root_inode->i_sb, &name); if (res) |
1da177e4c Linux-2.6.12-rc2 |
1406 |
d_instantiate(res, root_inode); |
1da177e4c Linux-2.6.12-rc2 |
1407 1408 1409 |
} return res; } |
ec4f86059 fs/dcache.c: Codi... |
1410 |
EXPORT_SYMBOL(d_alloc_root); |
1da177e4c Linux-2.6.12-rc2 |
1411 |
|
d891eedbc fs/dcache: allow ... |
1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 |
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; } static struct dentry * d_find_any_alias(struct inode *inode) { struct dentry *de; spin_lock(&inode->i_lock); de = __d_find_any_alias(inode); spin_unlock(&inode->i_lock); return de; } |
1da177e4c Linux-2.6.12-rc2 |
1432 |
/** |
4ea3ada29 [PATCH] new helpe... |
1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 |
* 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... |
1445 1446 1447 1448 |
* 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... |
1449 1450 1451 |
*/ struct dentry *d_obtain_alias(struct inode *inode) { |
9308a6128 [PATCH] kill d_al... |
1452 1453 1454 |
static const struct qstr anonstring = { .name = "" }; struct dentry *tmp; struct dentry *res; |
4ea3ada29 [PATCH] new helpe... |
1455 1456 |
if (!inode) |
440037287 [PATCH] switch al... |
1457 |
return ERR_PTR(-ESTALE); |
4ea3ada29 [PATCH] new helpe... |
1458 1459 |
if (IS_ERR(inode)) return ERR_CAST(inode); |
d891eedbc fs/dcache: allow ... |
1460 |
res = d_find_any_alias(inode); |
9308a6128 [PATCH] kill d_al... |
1461 1462 |
if (res) goto out_iput; |
a4464dbc0 Make ->d_sb assig... |
1463 |
tmp = __d_alloc(inode->i_sb, &anonstring); |
9308a6128 [PATCH] kill d_al... |
1464 1465 1466 |
if (!tmp) { res = ERR_PTR(-ENOMEM); goto out_iput; |
4ea3ada29 [PATCH] new helpe... |
1467 |
} |
b5c84bf6f fs: dcache remove... |
1468 |
|
873feea09 fs: dcache per-in... |
1469 |
spin_lock(&inode->i_lock); |
d891eedbc fs/dcache: allow ... |
1470 |
res = __d_find_any_alias(inode); |
9308a6128 [PATCH] kill d_al... |
1471 |
if (res) { |
873feea09 fs: dcache per-in... |
1472 |
spin_unlock(&inode->i_lock); |
9308a6128 [PATCH] kill d_al... |
1473 1474 1475 1476 1477 1478 |
dput(tmp); goto out_iput; } /* attach a disconnected dentry */ spin_lock(&tmp->d_lock); |
9308a6128 [PATCH] kill d_al... |
1479 1480 |
tmp->d_inode = inode; tmp->d_flags |= DCACHE_DISCONNECTED; |
9308a6128 [PATCH] kill d_al... |
1481 |
list_add(&tmp->d_alias, &inode->i_dentry); |
1879fd6a2 add hlist_bl_lock... |
1482 |
hlist_bl_lock(&tmp->d_sb->s_anon); |
ceb5bdc2d fs: dcache per-bu... |
1483 |
hlist_bl_add_head(&tmp->d_hash, &tmp->d_sb->s_anon); |
1879fd6a2 add hlist_bl_lock... |
1484 |
hlist_bl_unlock(&tmp->d_sb->s_anon); |
9308a6128 [PATCH] kill d_al... |
1485 |
spin_unlock(&tmp->d_lock); |
873feea09 fs: dcache per-in... |
1486 |
spin_unlock(&inode->i_lock); |
24ff6663c fs: call security... |
1487 |
security_d_instantiate(tmp, inode); |
9308a6128 [PATCH] kill d_al... |
1488 |
|
9308a6128 [PATCH] kill d_al... |
1489 1490 1491 |
return tmp; out_iput: |
24ff6663c fs: call security... |
1492 1493 |
if (res && !IS_ERR(res)) security_d_instantiate(res, inode); |
9308a6128 [PATCH] kill d_al... |
1494 1495 |
iput(inode); return res; |
4ea3ada29 [PATCH] new helpe... |
1496 |
} |
adc487204 EXPORT_SYMBOL(d_o... |
1497 |
EXPORT_SYMBOL(d_obtain_alias); |
1da177e4c Linux-2.6.12-rc2 |
1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 |
/** * 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... |
1518 1519 |
if (IS_ERR(inode)) return ERR_CAST(inode); |
21c0d8fdd [PATCH] knfsd: cl... |
1520 |
if (inode && S_ISDIR(inode->i_mode)) { |
873feea09 fs: dcache per-in... |
1521 |
spin_lock(&inode->i_lock); |
1da177e4c Linux-2.6.12-rc2 |
1522 1523 1524 |
new = __d_find_alias(inode, 1); if (new) { BUG_ON(!(new->d_flags & DCACHE_DISCONNECTED)); |
873feea09 fs: dcache per-in... |
1525 |
spin_unlock(&inode->i_lock); |
1da177e4c Linux-2.6.12-rc2 |
1526 |
security_d_instantiate(new, inode); |
1da177e4c Linux-2.6.12-rc2 |
1527 1528 1529 |
d_move(new, dentry); iput(inode); } else { |
873feea09 fs: dcache per-in... |
1530 |
/* already taking inode->i_lock, so d_add() by hand */ |
360da9002 [PATCH vfs-2.6 3/... |
1531 |
__d_instantiate(dentry, inode); |
873feea09 fs: dcache per-in... |
1532 |
spin_unlock(&inode->i_lock); |
1da177e4c Linux-2.6.12-rc2 |
1533 1534 1535 1536 1537 1538 1539 |
security_d_instantiate(dentry, inode); d_rehash(dentry); } } else d_add(dentry, inode); return new; } |
ec4f86059 fs/dcache.c: Codi... |
1540 |
EXPORT_SYMBOL(d_splice_alias); |
1da177e4c Linux-2.6.12-rc2 |
1541 |
|
9403540c0 dcache: Add case-... |
1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 |
/** * 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_... |
1558 |
struct dentry *d_add_ci(struct dentry *dentry, struct inode *inode, |
9403540c0 dcache: Add case-... |
1559 1560 1561 1562 1563 |
struct qstr *name) { int error; struct dentry *found; struct dentry *new; |
b6520c819 cleanup d_add_ci |
1564 1565 1566 1567 |
/* * First check if a dentry matching the name already exists, * if not go ahead and create it now. */ |
9403540c0 dcache: Add case-... |
1568 |
found = d_hash_and_lookup(dentry->d_parent, name); |
9403540c0 dcache: Add case-... |
1569 1570 1571 1572 1573 1574 |
if (!found) { new = d_alloc(dentry->d_parent, name); if (!new) { error = -ENOMEM; goto err_out; } |
b6520c819 cleanup d_add_ci |
1575 |
|
9403540c0 dcache: Add case-... |
1576 1577 1578 1579 1580 1581 1582 |
found = d_splice_alias(inode, new); if (found) { dput(new); return found; } return new; } |
b6520c819 cleanup d_add_ci |
1583 1584 1585 1586 1587 1588 1589 |
/* * 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-... |
1590 1591 1592 1593 1594 1595 |
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-... |
1596 1597 1598 |
iput(inode); return found; } |
b6520c819 cleanup d_add_ci |
1599 |
|
9403540c0 dcache: Add case-... |
1600 |
/* |
44396f4b5 fs: add a DCACHE_... |
1601 1602 |
* We are going to instantiate this dentry, unhash it and clear the * lookup flag so we can do that. |
9403540c0 dcache: Add case-... |
1603 |
*/ |
44396f4b5 fs: add a DCACHE_... |
1604 1605 |
if (unlikely(d_need_lookup(found))) d_clear_need_lookup(found); |
b6520c819 cleanup d_add_ci |
1606 |
|
9403540c0 dcache: Add case-... |
1607 |
/* |
9403540c0 dcache: Add case-... |
1608 |
* Negative dentry: instantiate it unless the inode is a directory and |
b6520c819 cleanup d_add_ci |
1609 |
* already has a dentry. |
9403540c0 dcache: Add case-... |
1610 |
*/ |
4513d899c switch d_add_ci()... |
1611 1612 1613 1614 |
new = d_splice_alias(inode, found); if (new) { dput(found); found = new; |
9403540c0 dcache: Add case-... |
1615 |
} |
4513d899c switch d_add_ci()... |
1616 |
return found; |
9403540c0 dcache: Add case-... |
1617 1618 1619 1620 1621 |
err_out: iput(inode); return ERR_PTR(error); } |
ec4f86059 fs/dcache.c: Codi... |
1622 |
EXPORT_SYMBOL(d_add_ci); |
1da177e4c Linux-2.6.12-rc2 |
1623 1624 |
/** |
31e6b01f4 fs: rcu-walk for ... |
1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 |
* __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 '... |
1657 |
struct hlist_bl_head *b = d_hash(parent, hash); |
ceb5bdc2d fs: dcache per-bu... |
1658 |
struct hlist_bl_node *node; |
31e6b01f4 fs: rcu-walk for ... |
1659 1660 1661 1662 1663 1664 1665 1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 |
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... |
1679 |
* See Documentation/filesystems/path-lookup.txt for more details. |
31e6b01f4 fs: rcu-walk for ... |
1680 |
*/ |
b07ad9967 vfs: get rid of '... |
1681 |
hlist_bl_for_each_entry_rcu(dentry, node, b, d_hash) { |
31e6b01f4 fs: rcu-walk for ... |
1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 |
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... |
1698 |
prefetch(tname); |
31e6b01f4 fs: rcu-walk for ... |
1699 1700 1701 1702 1703 1704 1705 1706 |
/* * 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... |
1707 |
if (unlikely(parent->d_flags & DCACHE_OP_COMPARE)) { |
31e6b01f4 fs: rcu-walk for ... |
1708 1709 1710 1711 1712 |
if (parent->d_op->d_compare(parent, *inode, dentry, i, tlen, tname, name)) continue; } else { |
9d55c369b fs: implement fas... |
1713 |
if (dentry_cmp(tname, tlen, str, len)) |
31e6b01f4 fs: rcu-walk for ... |
1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726 1727 1728 |
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 |
1729 1730 1731 |
* d_lookup - search for a dentry * @parent: parent dentry * @name: qstr of name we wish to find |
b04f784e5 fs: remove extra ... |
1732 |
* Returns: dentry, or NULL |
1da177e4c Linux-2.6.12-rc2 |
1733 |
* |
b04f784e5 fs: remove extra ... |
1734 1735 1736 1737 |
* 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 |
1738 |
*/ |
31e6b01f4 fs: rcu-walk for ... |
1739 |
struct dentry *d_lookup(struct dentry *parent, struct qstr *name) |
1da177e4c Linux-2.6.12-rc2 |
1740 |
{ |
31e6b01f4 fs: rcu-walk for ... |
1741 |
struct dentry *dentry; |
949854d02 fs: Use rename lo... |
1742 |
unsigned seq; |
1da177e4c Linux-2.6.12-rc2 |
1743 1744 1745 1746 1747 1748 1749 1750 1751 |
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... |
1752 |
EXPORT_SYMBOL(d_lookup); |
1da177e4c Linux-2.6.12-rc2 |
1753 |
|
31e6b01f4 fs: rcu-walk for ... |
1754 |
/** |
b04f784e5 fs: remove extra ... |
1755 1756 1757 1758 1759 1760 1761 1762 1763 1764 1765 1766 1767 1768 |
* __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 ... |
1769 |
struct dentry *__d_lookup(struct dentry *parent, struct qstr *name) |
1da177e4c Linux-2.6.12-rc2 |
1770 1771 1772 1773 |
{ unsigned int len = name->len; unsigned int hash = name->hash; const unsigned char *str = name->name; |
b07ad9967 vfs: get rid of '... |
1774 |
struct hlist_bl_head *b = d_hash(parent, hash); |
ceb5bdc2d fs: dcache per-bu... |
1775 |
struct hlist_bl_node *node; |
31e6b01f4 fs: rcu-walk for ... |
1776 |
struct dentry *found = NULL; |
665a7583f [PATCH] Remove hl... |
1777 |
struct dentry *dentry; |
1da177e4c Linux-2.6.12-rc2 |
1778 |
|
b04f784e5 fs: remove extra ... |
1779 |
/* |
31e6b01f4 fs: rcu-walk for ... |
1780 1781 1782 1783 1784 1785 1786 |
* 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 ... |
1787 1788 1789 1790 1791 1792 1793 1794 1795 1796 |
* 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... |
1797 |
* See Documentation/filesystems/path-lookup.txt for more details. |
b04f784e5 fs: remove extra ... |
1798 |
*/ |
1da177e4c Linux-2.6.12-rc2 |
1799 1800 |
rcu_read_lock(); |
b07ad9967 vfs: get rid of '... |
1801 |
hlist_bl_for_each_entry_rcu(dentry, node, b, d_hash) { |
31e6b01f4 fs: rcu-walk for ... |
1802 1803 |
const char *tname; int tlen; |
1da177e4c Linux-2.6.12-rc2 |
1804 |
|
1da177e4c Linux-2.6.12-rc2 |
1805 1806 |
if (dentry->d_name.hash != hash) continue; |
1da177e4c Linux-2.6.12-rc2 |
1807 1808 |
spin_lock(&dentry->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
1809 1810 |
if (dentry->d_parent != parent) goto next; |
d0185c088 Fix NULL pointer ... |
1811 1812 |
if (d_unhashed(dentry)) goto next; |
1da177e4c Linux-2.6.12-rc2 |
1813 1814 1815 1816 |
/* * It is safe to compare names since d_move() cannot * change the qstr (protected by d_lock). */ |
31e6b01f4 fs: rcu-walk for ... |
1817 1818 |
tlen = dentry->d_name.len; tname = dentry->d_name.name; |
fb045adb9 fs: dcache reduce... |
1819 |
if (parent->d_flags & DCACHE_OP_COMPARE) { |
621e155a3 fs: change d_comp... |
1820 1821 |
if (parent->d_op->d_compare(parent, parent->d_inode, dentry, dentry->d_inode, |
31e6b01f4 fs: rcu-walk for ... |
1822 |
tlen, tname, name)) |
1da177e4c Linux-2.6.12-rc2 |
1823 1824 |
goto next; } else { |
9d55c369b fs: implement fas... |
1825 |
if (dentry_cmp(tname, tlen, str, len)) |
1da177e4c Linux-2.6.12-rc2 |
1826 1827 |
goto next; } |
b7ab39f63 fs: dcache scale ... |
1828 |
dentry->d_count++; |
d0185c088 Fix NULL pointer ... |
1829 |
found = dentry; |
1da177e4c Linux-2.6.12-rc2 |
1830 1831 1832 1833 1834 1835 1836 1837 1838 1839 1840 |
spin_unlock(&dentry->d_lock); break; next: spin_unlock(&dentry->d_lock); } rcu_read_unlock(); return found; } /** |
3e7e241f8 [PATCH] dcache: A... |
1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 |
* 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... |
1857 |
if (dir->d_flags & DCACHE_OP_HASH) { |
b1e6a015a fs: change d_hash... |
1858 |
if (dir->d_op->d_hash(dir, dir->d_inode, name) < 0) |
3e7e241f8 [PATCH] dcache: A... |
1859 1860 1861 1862 1863 1864 1865 1866 |
goto out; } dentry = d_lookup(dir, name); out: return dentry; } /** |
786a5e15b fs: d_validate fixes |
1867 |
* d_validate - verify dentry provided from insecure source (deprecated) |
1da177e4c Linux-2.6.12-rc2 |
1868 |
* @dentry: The dentry alleged to be valid child of @dparent |
ff5fdb614 fs: fix new dcach... |
1869 |
* @dparent: The parent dentry (known to be valid) |
1da177e4c Linux-2.6.12-rc2 |
1870 1871 1872 1873 |
* * 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 |
1874 1875 |
* * This function is slow for big directories, and deprecated, do not use it. |
1da177e4c Linux-2.6.12-rc2 |
1876 |
*/ |
d3a23e167 Revert "fs: use R... |
1877 |
int d_validate(struct dentry *dentry, struct dentry *dparent) |
1da177e4c Linux-2.6.12-rc2 |
1878 |
{ |
786a5e15b fs: d_validate fixes |
1879 |
struct dentry *child; |
d3a23e167 Revert "fs: use R... |
1880 |
|
2fd6b7f50 fs: dcache scale ... |
1881 |
spin_lock(&dparent->d_lock); |
786a5e15b fs: d_validate fixes |
1882 1883 |
list_for_each_entry(child, &dparent->d_subdirs, d_u.d_child) { if (dentry == child) { |
2fd6b7f50 fs: dcache scale ... |
1884 |
spin_lock_nested(&dentry->d_lock, DENTRY_D_LOCK_NESTED); |
dc0474be3 fs: dcache ration... |
1885 |
__dget_dlock(dentry); |
2fd6b7f50 fs: dcache scale ... |
1886 1887 |
spin_unlock(&dentry->d_lock); spin_unlock(&dparent->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
1888 1889 1890 |
return 1; } } |
2fd6b7f50 fs: dcache scale ... |
1891 |
spin_unlock(&dparent->d_lock); |
786a5e15b fs: d_validate fixes |
1892 |
|
1da177e4c Linux-2.6.12-rc2 |
1893 1894 |
return 0; } |
ec4f86059 fs/dcache.c: Codi... |
1895 |
EXPORT_SYMBOL(d_validate); |
1da177e4c Linux-2.6.12-rc2 |
1896 1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 |
/* * 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... |
1920 |
struct inode *inode; |
7a91bf7f5 [PATCH] fsnotify_... |
1921 |
int isdir = 0; |
1da177e4c Linux-2.6.12-rc2 |
1922 1923 1924 |
/* * Are we the only user? */ |
357f8e658 fs: dcache reduce... |
1925 |
again: |
1da177e4c Linux-2.6.12-rc2 |
1926 |
spin_lock(&dentry->d_lock); |
873feea09 fs: dcache per-in... |
1927 1928 |
inode = dentry->d_inode; isdir = S_ISDIR(inode->i_mode); |
b7ab39f63 fs: dcache scale ... |
1929 |
if (dentry->d_count == 1) { |
873feea09 fs: dcache per-in... |
1930 |
if (inode && !spin_trylock(&inode->i_lock)) { |
357f8e658 fs: dcache reduce... |
1931 1932 1933 1934 |
spin_unlock(&dentry->d_lock); cpu_relax(); goto again; } |
13e3c5e5b clean DCACHE_CANT... |
1935 |
dentry->d_flags &= ~DCACHE_CANT_MOUNT; |
31e6b01f4 fs: rcu-walk for ... |
1936 |
dentry_unlink_inode(dentry); |
7a91bf7f5 [PATCH] fsnotify_... |
1937 |
fsnotify_nameremove(dentry, isdir); |
1da177e4c Linux-2.6.12-rc2 |
1938 1939 1940 1941 1942 1943 1944 |
return; } if (!d_unhashed(dentry)) __d_drop(dentry); spin_unlock(&dentry->d_lock); |
7a91bf7f5 [PATCH] fsnotify_... |
1945 1946 |
fsnotify_nameremove(dentry, isdir); |
1da177e4c Linux-2.6.12-rc2 |
1947 |
} |
ec4f86059 fs/dcache.c: Codi... |
1948 |
EXPORT_SYMBOL(d_delete); |
1da177e4c Linux-2.6.12-rc2 |
1949 |
|
b07ad9967 vfs: get rid of '... |
1950 |
static void __d_rehash(struct dentry * entry, struct hlist_bl_head *b) |
1da177e4c Linux-2.6.12-rc2 |
1951 |
{ |
ceb5bdc2d fs: dcache per-bu... |
1952 |
BUG_ON(!d_unhashed(entry)); |
1879fd6a2 add hlist_bl_lock... |
1953 |
hlist_bl_lock(b); |
dea3667bc vfs: get rid of i... |
1954 |
entry->d_flags |= DCACHE_RCUACCESS; |
b07ad9967 vfs: get rid of '... |
1955 |
hlist_bl_add_head_rcu(&entry->d_hash, b); |
1879fd6a2 add hlist_bl_lock... |
1956 |
hlist_bl_unlock(b); |
1da177e4c Linux-2.6.12-rc2 |
1957 |
} |
770bfad84 NFS: Add dentry m... |
1958 1959 1960 1961 |
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 |
1962 1963 1964 1965 1966 1967 1968 1969 1970 |
/** * 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 |
1971 |
spin_lock(&entry->d_lock); |
770bfad84 NFS: Add dentry m... |
1972 |
_d_rehash(entry); |
1da177e4c Linux-2.6.12-rc2 |
1973 |
spin_unlock(&entry->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
1974 |
} |
ec4f86059 fs/dcache.c: Codi... |
1975 |
EXPORT_SYMBOL(d_rehash); |
1da177e4c Linux-2.6.12-rc2 |
1976 |
|
fb2d5b86a fs: name case upd... |
1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 |
/** * 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... |
1993 |
BUG_ON(!mutex_is_locked(&dentry->d_parent->d_inode->i_mutex)); |
fb2d5b86a fs: name case upd... |
1994 |
BUG_ON(dentry->d_name.len != name->len); /* d_lookup gives this */ |
fb2d5b86a fs: name case upd... |
1995 |
spin_lock(&dentry->d_lock); |
31e6b01f4 fs: rcu-walk for ... |
1996 |
write_seqcount_begin(&dentry->d_seq); |
fb2d5b86a fs: name case upd... |
1997 |
memcpy((unsigned char *)dentry->d_name.name, name->name, name->len); |
31e6b01f4 fs: rcu-walk for ... |
1998 |
write_seqcount_end(&dentry->d_seq); |
fb2d5b86a fs: name case upd... |
1999 |
spin_unlock(&dentry->d_lock); |
fb2d5b86a fs: name case upd... |
2000 2001 |
} EXPORT_SYMBOL(dentry_update_name_case); |
1da177e4c Linux-2.6.12-rc2 |
2002 2003 2004 2005 2006 2007 2008 |
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... |
2009 |
swap(target->d_name.name, dentry->d_name.name); |
1da177e4c Linux-2.6.12-rc2 |
2010 2011 2012 2013 2014 |
} else { /* * dentry:internal, target:external. Steal target's * storage and make target internal. */ |
321bcf921 dcache: don't exp... |
2015 2016 |
memcpy(target->d_iname, dentry->d_name.name, dentry->d_name.len + 1); |
1da177e4c Linux-2.6.12-rc2 |
2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 |
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(... |
2036 2037 |
dentry->d_name.len = target->d_name.len; return; |
1da177e4c Linux-2.6.12-rc2 |
2038 2039 |
} } |
9a8d5bb4a generic swap(): d... |
2040 |
swap(dentry->d_name.len, target->d_name.len); |
1da177e4c Linux-2.6.12-rc2 |
2041 |
} |
2fd6b7f50 fs: dcache scale ... |
2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076 |
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 |
2077 |
/* |
2fd6b7f50 fs: dcache scale ... |
2078 2079 2080 2081 2082 2083 2084 2085 2086 |
* 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 |
2087 |
*/ |
9eaef27b3 [PATCH] VFS: Make... |
2088 |
/* |
183675011 fix loop checks i... |
2089 |
* __d_move - move a dentry |
1da177e4c Linux-2.6.12-rc2 |
2090 2091 2092 2093 |
* @dentry: entry to move * @target: new dentry * * Update the dcache to reflect the move of a file name. Negative |
c46c88774 vfs: document loc... |
2094 2095 2096 |
* 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 |
2097 |
*/ |
183675011 fix loop checks i... |
2098 |
static void __d_move(struct dentry * dentry, struct dentry * target) |
1da177e4c Linux-2.6.12-rc2 |
2099 |
{ |
1da177e4c Linux-2.6.12-rc2 |
2100 2101 2102 |
if (!dentry->d_inode) printk(KERN_WARNING "VFS: moving negative dcache entry "); |
2fd6b7f50 fs: dcache scale ... |
2103 2104 |
BUG_ON(d_ancestor(dentry, target)); BUG_ON(d_ancestor(target, dentry)); |
2fd6b7f50 fs: dcache scale ... |
2105 |
dentry_lock_for_move(dentry, target); |
1da177e4c Linux-2.6.12-rc2 |
2106 |
|
31e6b01f4 fs: rcu-walk for ... |
2107 2108 |
write_seqcount_begin(&dentry->d_seq); write_seqcount_begin(&target->d_seq); |
ceb5bdc2d fs: dcache per-bu... |
2109 2110 2111 2112 2113 2114 2115 |
/* __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 ... |
2116 |
__d_rehash(dentry, d_hash(target->d_parent, target->d_name.hash)); |
1da177e4c Linux-2.6.12-rc2 |
2117 2118 2119 |
/* Unhash the target: dput() will then get rid of it */ __d_drop(target); |
5160ee6fc [PATCH] shrink de... |
2120 2121 |
list_del(&dentry->d_u.d_child); list_del(&target->d_u.d_child); |
1da177e4c Linux-2.6.12-rc2 |
2122 2123 2124 |
/* Switch the names.. */ switch_names(dentry, target); |
9a8d5bb4a generic swap(): d... |
2125 |
swap(dentry->d_name.hash, target->d_name.hash); |
1da177e4c Linux-2.6.12-rc2 |
2126 2127 2128 2129 2130 |
/* ... and switch the parents */ if (IS_ROOT(dentry)) { dentry->d_parent = target->d_parent; target->d_parent = target; |
5160ee6fc [PATCH] shrink de... |
2131 |
INIT_LIST_HEAD(&target->d_u.d_child); |
1da177e4c Linux-2.6.12-rc2 |
2132 |
} else { |
9a8d5bb4a generic swap(): d... |
2133 |
swap(dentry->d_parent, target->d_parent); |
1da177e4c Linux-2.6.12-rc2 |
2134 2135 |
/* And add them back to the (new) parent lists */ |
5160ee6fc [PATCH] shrink de... |
2136 |
list_add(&target->d_u.d_child, &target->d_parent->d_subdirs); |
1da177e4c Linux-2.6.12-rc2 |
2137 |
} |
5160ee6fc [PATCH] shrink de... |
2138 |
list_add(&dentry->d_u.d_child, &dentry->d_parent->d_subdirs); |
2fd6b7f50 fs: dcache scale ... |
2139 |
|
31e6b01f4 fs: rcu-walk for ... |
2140 2141 |
write_seqcount_end(&target->d_seq); write_seqcount_end(&dentry->d_seq); |
2fd6b7f50 fs: dcache scale ... |
2142 |
dentry_unlock_parents_for_move(dentry, target); |
1da177e4c Linux-2.6.12-rc2 |
2143 |
spin_unlock(&target->d_lock); |
c32ccd87b [PATCH] inotify: ... |
2144 |
fsnotify_d_move(dentry); |
1da177e4c Linux-2.6.12-rc2 |
2145 |
spin_unlock(&dentry->d_lock); |
183675011 fix loop checks i... |
2146 2147 2148 2149 2150 2151 2152 2153 |
} /* * 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... |
2154 2155 |
* dcache entries should not be moved in this way. See the locking * requirements for __d_move. |
183675011 fix loop checks i... |
2156 2157 2158 2159 2160 |
*/ void d_move(struct dentry *dentry, struct dentry *target) { write_seqlock(&rename_lock); __d_move(dentry, target); |
1da177e4c Linux-2.6.12-rc2 |
2161 |
write_sequnlock(&rename_lock); |
9eaef27b3 [PATCH] VFS: Make... |
2162 |
} |
ec4f86059 fs/dcache.c: Codi... |
2163 |
EXPORT_SYMBOL(d_move); |
1da177e4c Linux-2.6.12-rc2 |
2164 |
|
e2761a116 [PATCH vfs-2.6 2/... |
2165 2166 2167 2168 2169 2170 2171 |
/** * 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... |
2172 |
*/ |
e2761a116 [PATCH vfs-2.6 2/... |
2173 |
struct dentry *d_ancestor(struct dentry *p1, struct dentry *p2) |
9eaef27b3 [PATCH] VFS: Make... |
2174 2175 |
{ struct dentry *p; |
871c0067d [PATCH vfs-2.6 1/... |
2176 |
for (p = p2; !IS_ROOT(p); p = p->d_parent) { |
9eaef27b3 [PATCH] VFS: Make... |
2177 |
if (p->d_parent == p1) |
e2761a116 [PATCH vfs-2.6 2/... |
2178 |
return p; |
9eaef27b3 [PATCH] VFS: Make... |
2179 |
} |
e2761a116 [PATCH vfs-2.6 2/... |
2180 |
return NULL; |
9eaef27b3 [PATCH] VFS: Make... |
2181 2182 2183 2184 2185 2186 |
} /* * This helper attempts to cope with remotely renamed directories * * It assumes that the caller is already holding |
183675011 fix loop checks i... |
2187 |
* dentry->d_parent->d_inode->i_mutex, inode->i_lock and rename_lock |
9eaef27b3 [PATCH] VFS: Make... |
2188 2189 2190 |
* * Note: If ever the locking in lock_rename() changes, then please * remember to update this too... |
9eaef27b3 [PATCH] VFS: Make... |
2191 |
*/ |
873feea09 fs: dcache per-in... |
2192 2193 |
static struct dentry *__d_unalias(struct inode *inode, struct dentry *dentry, struct dentry *alias) |
9eaef27b3 [PATCH] VFS: Make... |
2194 2195 2196 2197 2198 2199 2200 |
{ 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... |
2201 2202 2203 2204 2205 2206 2207 2208 2209 |
/* 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... |
2210 |
__d_move(alias, dentry); |
9eaef27b3 [PATCH] VFS: Make... |
2211 2212 |
ret = alias; out_err: |
873feea09 fs: dcache per-in... |
2213 |
spin_unlock(&inode->i_lock); |
9eaef27b3 [PATCH] VFS: Make... |
2214 2215 2216 2217 2218 2219 2220 2221 |
if (m2) mutex_unlock(m2); if (m1) mutex_unlock(m1); return ret; } /* |
770bfad84 NFS: Add dentry m... |
2222 2223 |
* 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 ... |
2224 |
* returns with anon->d_lock held! |
770bfad84 NFS: Add dentry m... |
2225 2226 2227 2228 |
*/ static void __d_materialise_dentry(struct dentry *dentry, struct dentry *anon) { struct dentry *dparent, *aparent; |
2fd6b7f50 fs: dcache scale ... |
2229 |
dentry_lock_for_move(anon, dentry); |
770bfad84 NFS: Add dentry m... |
2230 |
|
31e6b01f4 fs: rcu-walk for ... |
2231 2232 |
write_seqcount_begin(&dentry->d_seq); write_seqcount_begin(&anon->d_seq); |
770bfad84 NFS: Add dentry m... |
2233 2234 |
dparent = dentry->d_parent; aparent = anon->d_parent; |
2fd6b7f50 fs: dcache scale ... |
2235 2236 |
switch_names(dentry, anon); swap(dentry->d_name.hash, anon->d_name.hash); |
770bfad84 NFS: Add dentry m... |
2237 2238 2239 2240 2241 2242 2243 2244 2245 2246 2247 2248 2249 |
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 ... |
2250 2251 |
write_seqcount_end(&dentry->d_seq); write_seqcount_end(&anon->d_seq); |
2fd6b7f50 fs: dcache scale ... |
2252 2253 2254 2255 |
dentry_unlock_parents_for_move(anon, dentry); spin_unlock(&dentry->d_lock); /* anon->d_lock still locked, returns locked */ |
770bfad84 NFS: Add dentry m... |
2256 2257 2258 2259 2260 2261 2262 2263 2264 |
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... |
2265 2266 |
* 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... |
2267 2268 2269 |
*/ struct dentry *d_materialise_unique(struct dentry *dentry, struct inode *inode) { |
9eaef27b3 [PATCH] VFS: Make... |
2270 |
struct dentry *actual; |
770bfad84 NFS: Add dentry m... |
2271 2272 |
BUG_ON(!d_unhashed(dentry)); |
770bfad84 NFS: Add dentry m... |
2273 2274 |
if (!inode) { actual = dentry; |
360da9002 [PATCH vfs-2.6 3/... |
2275 |
__d_instantiate(dentry, NULL); |
357f8e658 fs: dcache reduce... |
2276 2277 |
d_rehash(actual); goto out_nolock; |
770bfad84 NFS: Add dentry m... |
2278 |
} |
873feea09 fs: dcache per-in... |
2279 |
spin_lock(&inode->i_lock); |
357f8e658 fs: dcache reduce... |
2280 |
|
9eaef27b3 [PATCH] VFS: Make... |
2281 2282 2283 2284 2285 2286 2287 |
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... |
2288 2289 2290 2291 2292 2293 2294 2295 |
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... |
2296 |
__d_materialise_dentry(dentry, alias); |
183675011 fix loop checks i... |
2297 |
write_sequnlock(&rename_lock); |
9eaef27b3 [PATCH] VFS: Make... |
2298 2299 |
__d_drop(alias); goto found; |
183675011 fix loop checks i... |
2300 2301 2302 2303 |
} else { /* Nope, but we must(!) avoid directory * aliasing */ actual = __d_unalias(inode, dentry, alias); |
9eaef27b3 [PATCH] VFS: Make... |
2304 |
} |
183675011 fix loop checks i... |
2305 |
write_sequnlock(&rename_lock); |
9eaef27b3 [PATCH] VFS: Make... |
2306 2307 2308 2309 |
if (IS_ERR(actual)) dput(alias); goto out_nolock; } |
770bfad84 NFS: Add dentry m... |
2310 2311 2312 2313 2314 2315 |
} /* Add a unique reference */ actual = __d_instantiate_unique(dentry, inode); if (!actual) actual = dentry; |
357f8e658 fs: dcache reduce... |
2316 2317 |
else BUG_ON(!d_unhashed(actual)); |
770bfad84 NFS: Add dentry m... |
2318 |
|
770bfad84 NFS: Add dentry m... |
2319 2320 2321 2322 |
spin_lock(&actual->d_lock); found: _d_rehash(actual); spin_unlock(&actual->d_lock); |
873feea09 fs: dcache per-in... |
2323 |
spin_unlock(&inode->i_lock); |
9eaef27b3 [PATCH] VFS: Make... |
2324 |
out_nolock: |
770bfad84 NFS: Add dentry m... |
2325 2326 2327 2328 2329 2330 2331 |
if (actual == dentry) { security_d_instantiate(dentry, inode); return NULL; } iput(inode); return actual; |
770bfad84 NFS: Add dentry m... |
2332 |
} |
ec4f86059 fs/dcache.c: Codi... |
2333 |
EXPORT_SYMBOL_GPL(d_materialise_unique); |
770bfad84 NFS: Add dentry m... |
2334 |
|
cdd16d026 [patch 2/3] vfs: ... |
2335 |
static int prepend(char **buffer, int *buflen, const char *str, int namelen) |
6092d0481 [patch 1/7] vfs: ... |
2336 2337 2338 2339 2340 2341 2342 2343 |
{ *buflen -= namelen; if (*buflen < 0) return -ENAMETOOLONG; *buffer -= namelen; memcpy(*buffer, str, namelen); return 0; } |
cdd16d026 [patch 2/3] vfs: ... |
2344 2345 2346 2347 |
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 |
2348 |
/** |
208898c17 fs: fix kernel-do... |
2349 |
* prepend_path - Prepend path string to a buffer |
9d1bc6013 [patch 2/7] vfs: ... |
2350 2351 |
* @path: the dentry/vfsmount to report * @root: root vfsmnt/dentry (may be modified by this function) |
f2eb6575d vfs: add prepend_... |
2352 2353 |
* @buffer: pointer to the end of the buffer * @buflen: pointer to buffer length |
552ce544e Revert "[PATCH] F... |
2354 |
* |
949854d02 fs: Use rename lo... |
2355 |
* Caller holds the rename_lock. |
9d1bc6013 [patch 2/7] vfs: ... |
2356 2357 2358 |
* * If path is not reachable from the supplied root, then the value of * root is changed (without modifying refcounts). |
1da177e4c Linux-2.6.12-rc2 |
2359 |
*/ |
f2eb6575d vfs: add prepend_... |
2360 2361 |
static int prepend_path(const struct path *path, struct path *root, char **buffer, int *buflen) |
1da177e4c Linux-2.6.12-rc2 |
2362 |
{ |
9d1bc6013 [patch 2/7] vfs: ... |
2363 2364 |
struct dentry *dentry = path->dentry; struct vfsmount *vfsmnt = path->mnt; |
f2eb6575d vfs: add prepend_... |
2365 2366 |
bool slash = false; int error = 0; |
6092d0481 [patch 1/7] vfs: ... |
2367 |
|
99b7db7b8 fs: brlock vfsmou... |
2368 |
br_read_lock(vfsmount_lock); |
f2eb6575d vfs: add prepend_... |
2369 |
while (dentry != root->dentry || vfsmnt != root->mnt) { |
1da177e4c Linux-2.6.12-rc2 |
2370 |
struct dentry * parent; |
1da177e4c Linux-2.6.12-rc2 |
2371 |
if (dentry == vfsmnt->mnt_root || IS_ROOT(dentry)) { |
552ce544e Revert "[PATCH] F... |
2372 |
/* Global root? */ |
1da177e4c Linux-2.6.12-rc2 |
2373 |
if (vfsmnt->mnt_parent == vfsmnt) { |
1da177e4c Linux-2.6.12-rc2 |
2374 2375 2376 2377 |
goto global_root; } dentry = vfsmnt->mnt_mountpoint; vfsmnt = vfsmnt->mnt_parent; |
1da177e4c Linux-2.6.12-rc2 |
2378 2379 2380 2381 |
continue; } parent = dentry->d_parent; prefetch(parent); |
9abca3608 fs: increase d_na... |
2382 |
spin_lock(&dentry->d_lock); |
f2eb6575d vfs: add prepend_... |
2383 |
error = prepend_name(buffer, buflen, &dentry->d_name); |
9abca3608 fs: increase d_na... |
2384 |
spin_unlock(&dentry->d_lock); |
f2eb6575d vfs: add prepend_... |
2385 2386 2387 2388 2389 2390 |
if (!error) error = prepend(buffer, buflen, "/", 1); if (error) break; slash = true; |
1da177e4c Linux-2.6.12-rc2 |
2391 2392 |
dentry = parent; } |
be285c712 [patch 3/3] vfs: ... |
2393 |
out: |
f2eb6575d vfs: add prepend_... |
2394 2395 |
if (!error && !slash) error = prepend(buffer, buflen, "/", 1); |
99b7db7b8 fs: brlock vfsmou... |
2396 |
br_read_unlock(vfsmount_lock); |
f2eb6575d vfs: add prepend_... |
2397 |
return error; |
1da177e4c Linux-2.6.12-rc2 |
2398 2399 |
global_root: |
98dc568bc vfs: __d_path: do... |
2400 2401 2402 2403 2404 2405 2406 2407 2408 2409 |
/* * 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); } |
9d1bc6013 [patch 2/7] vfs: ... |
2410 2411 |
root->mnt = vfsmnt; root->dentry = dentry; |
be285c712 [patch 3/3] vfs: ... |
2412 |
goto out; |
f2eb6575d vfs: add prepend_... |
2413 |
} |
be285c712 [patch 3/3] vfs: ... |
2414 |
|
f2eb6575d vfs: add prepend_... |
2415 2416 2417 2418 |
/** * __d_path - return the path of a dentry * @path: the dentry/vfsmount to report * @root: root vfsmnt/dentry (may be modified by this function) |
cd956a1c0 fs/dcache: fix fu... |
2419 |
* @buf: buffer to return value in |
f2eb6575d vfs: add prepend_... |
2420 2421 |
* @buflen: buffer length * |
ffd1f4ed5 vfs: only add " (... |
2422 |
* Convert a dentry into an ASCII path name. |
f2eb6575d vfs: add prepend_... |
2423 2424 2425 2426 |
* * Returns a pointer into the buffer or an error code if the * path was too long. * |
be148247c fs: take dcache_l... |
2427 |
* "buflen" should be positive. |
f2eb6575d vfs: add prepend_... |
2428 2429 2430 2431 2432 2433 2434 2435 2436 2437 2438 |
* * If path is not reachable from the supplied root, then the value of * root is changed (without modifying refcounts). */ char *__d_path(const struct path *path, struct path *root, char *buf, int buflen) { char *res = buf + buflen; int error; prepend(&res, &buflen, "\0", 1); |
949854d02 fs: Use rename lo... |
2439 |
write_seqlock(&rename_lock); |
f2eb6575d vfs: add prepend_... |
2440 |
error = prepend_path(path, root, &res, &buflen); |
949854d02 fs: Use rename lo... |
2441 |
write_sequnlock(&rename_lock); |
be148247c fs: take dcache_l... |
2442 |
|
f2eb6575d vfs: add prepend_... |
2443 2444 |
if (error) return ERR_PTR(error); |
f2eb6575d vfs: add prepend_... |
2445 |
return res; |
1da177e4c Linux-2.6.12-rc2 |
2446 |
} |
ffd1f4ed5 vfs: only add " (... |
2447 2448 2449 2450 2451 2452 2453 2454 2455 2456 2457 2458 2459 2460 2461 |
/* * same as __d_path but appends "(deleted)" for unlinked files. */ static int path_with_deleted(const struct path *path, struct path *root, char **buf, int *buflen) { 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... |
2462 2463 2464 2465 |
static int prepend_unreachable(char **buffer, int *buflen) { return prepend(buffer, buflen, "(unreachable)", 13); } |
a03a8a709 d_path: kerneldoc... |
2466 2467 |
/** * d_path - return the path of a dentry |
cf28b4863 d_path: Make d_pa... |
2468 |
* @path: path to report |
a03a8a709 d_path: kerneldoc... |
2469 2470 2471 2472 2473 2474 |
* @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... |
2475 2476 2477 2478 |
* 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... |
2479 |
* |
31f3e0b3a [patch 1/3] vfs: ... |
2480 |
* "buflen" should be positive. |
a03a8a709 d_path: kerneldoc... |
2481 |
*/ |
20d4fdc1a [patch 2/4] fs: m... |
2482 |
char *d_path(const struct path *path, char *buf, int buflen) |
1da177e4c Linux-2.6.12-rc2 |
2483 |
{ |
ffd1f4ed5 vfs: only add " (... |
2484 |
char *res = buf + buflen; |
6ac08c39a Use struct path i... |
2485 |
struct path root; |
9d1bc6013 [patch 2/7] vfs: ... |
2486 |
struct path tmp; |
ffd1f4ed5 vfs: only add " (... |
2487 |
int error; |
1da177e4c Linux-2.6.12-rc2 |
2488 |
|
c23fbb6bc VFS: delay the de... |
2489 2490 2491 2492 2493 2494 2495 |
/* * 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... |
2496 2497 |
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... |
2498 |
|
f7ad3c6be vfs: add helpers ... |
2499 |
get_fs_root(current->fs, &root); |
949854d02 fs: Use rename lo... |
2500 |
write_seqlock(&rename_lock); |
9d1bc6013 [patch 2/7] vfs: ... |
2501 |
tmp = root; |
ffd1f4ed5 vfs: only add " (... |
2502 2503 2504 |
error = path_with_deleted(path, &tmp, &res, &buflen); if (error) res = ERR_PTR(error); |
949854d02 fs: Use rename lo... |
2505 |
write_sequnlock(&rename_lock); |
6ac08c39a Use struct path i... |
2506 |
path_put(&root); |
1da177e4c Linux-2.6.12-rc2 |
2507 2508 |
return res; } |
ec4f86059 fs/dcache.c: Codi... |
2509 |
EXPORT_SYMBOL(d_path); |
1da177e4c Linux-2.6.12-rc2 |
2510 |
|
8df9d1a41 vfs: show unreach... |
2511 2512 2513 2514 2515 2516 2517 2518 2519 2520 2521 2522 2523 2524 2525 2526 2527 2528 2529 2530 |
/** * 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; struct path tmp; 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... |
2531 |
write_seqlock(&rename_lock); |
8df9d1a41 vfs: show unreach... |
2532 2533 2534 2535 |
tmp = root; error = path_with_deleted(path, &tmp, &res, &buflen); if (!error && !path_equal(&tmp, &root)) error = prepend_unreachable(&res, &buflen); |
949854d02 fs: Use rename lo... |
2536 |
write_sequnlock(&rename_lock); |
8df9d1a41 vfs: show unreach... |
2537 2538 2539 2540 2541 2542 |
path_put(&root); if (error) res = ERR_PTR(error); return res; } |
1da177e4c Linux-2.6.12-rc2 |
2543 |
/* |
c23fbb6bc VFS: delay the de... |
2544 2545 2546 2547 2548 2549 2550 2551 2552 2553 2554 2555 2556 2557 2558 2559 2560 2561 2562 2563 2564 |
* 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: ... |
2565 2566 |
* Write full pathname from the root of the filesystem into the buffer. */ |
ec2447c27 hostfs: simplify ... |
2567 |
static char *__dentry_path(struct dentry *dentry, char *buf, int buflen) |
6092d0481 [patch 1/7] vfs: ... |
2568 2569 2570 |
{ char *end = buf + buflen; char *retval; |
6092d0481 [patch 1/7] vfs: ... |
2571 |
prepend(&end, &buflen, "\0", 1); |
6092d0481 [patch 1/7] vfs: ... |
2572 2573 2574 2575 2576 |
if (buflen < 1) goto Elong; /* Get '/' right */ retval = end-1; *retval = '/'; |
cdd16d026 [patch 2/3] vfs: ... |
2577 2578 |
while (!IS_ROOT(dentry)) { struct dentry *parent = dentry->d_parent; |
9abca3608 fs: increase d_na... |
2579 |
int error; |
6092d0481 [patch 1/7] vfs: ... |
2580 |
|
6092d0481 [patch 1/7] vfs: ... |
2581 |
prefetch(parent); |
9abca3608 fs: increase d_na... |
2582 2583 2584 2585 |
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: ... |
2586 2587 2588 2589 2590 |
goto Elong; retval = end; dentry = parent; } |
c103135c1 new helper: __den... |
2591 2592 2593 2594 |
return retval; Elong: return ERR_PTR(-ENAMETOOLONG); } |
ec2447c27 hostfs: simplify ... |
2595 2596 2597 2598 |
char *dentry_path_raw(struct dentry *dentry, char *buf, int buflen) { char *retval; |
949854d02 fs: Use rename lo... |
2599 |
write_seqlock(&rename_lock); |
ec2447c27 hostfs: simplify ... |
2600 |
retval = __dentry_path(dentry, buf, buflen); |
949854d02 fs: Use rename lo... |
2601 |
write_sequnlock(&rename_lock); |
ec2447c27 hostfs: simplify ... |
2602 2603 2604 2605 |
return retval; } EXPORT_SYMBOL(dentry_path_raw); |
c103135c1 new helper: __den... |
2606 2607 2608 2609 2610 |
char *dentry_path(struct dentry *dentry, char *buf, int buflen) { char *p = NULL; char *retval; |
949854d02 fs: Use rename lo... |
2611 |
write_seqlock(&rename_lock); |
c103135c1 new helper: __den... |
2612 2613 2614 2615 2616 2617 2618 |
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... |
2619 |
write_sequnlock(&rename_lock); |
c103135c1 new helper: __den... |
2620 2621 |
if (!IS_ERR(retval) && p) *p = '/'; /* restore '/' overriden with '\0' */ |
6092d0481 [patch 1/7] vfs: ... |
2622 2623 |
return retval; Elong: |
6092d0481 [patch 1/7] vfs: ... |
2624 2625 2626 2627 |
return ERR_PTR(-ENAMETOOLONG); } /* |
1da177e4c Linux-2.6.12-rc2 |
2628 2629 2630 2631 2632 2633 2634 2635 2636 2637 2638 2639 2640 2641 2642 2643 2644 |
* 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... |
2645 |
SYSCALL_DEFINE2(getcwd, char __user *, buf, unsigned long, size) |
1da177e4c Linux-2.6.12-rc2 |
2646 |
{ |
552ce544e Revert "[PATCH] F... |
2647 |
int error; |
6ac08c39a Use struct path i... |
2648 |
struct path pwd, root; |
552ce544e Revert "[PATCH] F... |
2649 |
char *page = (char *) __get_free_page(GFP_USER); |
1da177e4c Linux-2.6.12-rc2 |
2650 2651 2652 |
if (!page) return -ENOMEM; |
f7ad3c6be vfs: add helpers ... |
2653 |
get_fs_root_and_pwd(current->fs, &root, &pwd); |
1da177e4c Linux-2.6.12-rc2 |
2654 |
|
552ce544e Revert "[PATCH] F... |
2655 |
error = -ENOENT; |
949854d02 fs: Use rename lo... |
2656 |
write_seqlock(&rename_lock); |
f3da392e9 dcache: extrace a... |
2657 |
if (!d_unlinked(pwd.dentry)) { |
552ce544e Revert "[PATCH] F... |
2658 |
unsigned long len; |
9d1bc6013 [patch 2/7] vfs: ... |
2659 |
struct path tmp = root; |
8df9d1a41 vfs: show unreach... |
2660 2661 |
char *cwd = page + PAGE_SIZE; int buflen = PAGE_SIZE; |
1da177e4c Linux-2.6.12-rc2 |
2662 |
|
8df9d1a41 vfs: show unreach... |
2663 2664 |
prepend(&cwd, &buflen, "\0", 1); error = prepend_path(&pwd, &tmp, &cwd, &buflen); |
949854d02 fs: Use rename lo... |
2665 |
write_sequnlock(&rename_lock); |
552ce544e Revert "[PATCH] F... |
2666 |
|
8df9d1a41 vfs: show unreach... |
2667 |
if (error) |
552ce544e Revert "[PATCH] F... |
2668 |
goto out; |
8df9d1a41 vfs: show unreach... |
2669 2670 2671 2672 2673 2674 |
/* Unreachable from current root */ if (!path_equal(&tmp, &root)) { error = prepend_unreachable(&cwd, &buflen); if (error) goto out; } |
552ce544e Revert "[PATCH] F... |
2675 2676 2677 2678 2679 2680 2681 |
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... |
2682 2683 |
} else { write_sequnlock(&rename_lock); |
949854d02 fs: Use rename lo... |
2684 |
} |
1da177e4c Linux-2.6.12-rc2 |
2685 2686 |
out: |
6ac08c39a Use struct path i... |
2687 2688 |
path_put(&pwd); path_put(&root); |
1da177e4c Linux-2.6.12-rc2 |
2689 2690 2691 2692 2693 2694 2695 2696 2697 2698 2699 2700 2701 2702 2703 2704 2705 2706 2707 2708 |
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/... |
2709 |
int is_subdir(struct dentry *new_dentry, struct dentry *old_dentry) |
1da177e4c Linux-2.6.12-rc2 |
2710 2711 |
{ int result; |
949854d02 fs: Use rename lo... |
2712 |
unsigned seq; |
1da177e4c Linux-2.6.12-rc2 |
2713 |
|
e2761a116 [PATCH vfs-2.6 2/... |
2714 2715 |
if (new_dentry == old_dentry) return 1; |
e2761a116 [PATCH vfs-2.6 2/... |
2716 |
do { |
1da177e4c Linux-2.6.12-rc2 |
2717 |
/* for restarting inner loop in case of seq retry */ |
1da177e4c Linux-2.6.12-rc2 |
2718 |
seq = read_seqbegin(&rename_lock); |
949854d02 fs: Use rename lo... |
2719 2720 2721 2722 2723 |
/* * Need rcu_readlock to protect against the d_parent trashing * due to d_move */ rcu_read_lock(); |
e2761a116 [PATCH vfs-2.6 2/... |
2724 |
if (d_ancestor(old_dentry, new_dentry)) |
1da177e4c Linux-2.6.12-rc2 |
2725 |
result = 1; |
e2761a116 [PATCH vfs-2.6 2/... |
2726 2727 |
else result = 0; |
949854d02 fs: Use rename lo... |
2728 |
rcu_read_unlock(); |
1da177e4c Linux-2.6.12-rc2 |
2729 |
} while (read_seqretry(&rename_lock, seq)); |
1da177e4c Linux-2.6.12-rc2 |
2730 2731 2732 |
return result; } |
2096f759a New helper: path_... |
2733 2734 2735 2736 2737 |
int path_is_under(struct path *path1, struct path *path2) { struct vfsmount *mnt = path1->mnt; struct dentry *dentry = path1->dentry; int res; |
99b7db7b8 fs: brlock vfsmou... |
2738 2739 |
br_read_lock(vfsmount_lock); |
2096f759a New helper: path_... |
2740 2741 2742 |
if (mnt != path2->mnt) { for (;;) { if (mnt->mnt_parent == mnt) { |
99b7db7b8 fs: brlock vfsmou... |
2743 |
br_read_unlock(vfsmount_lock); |
2096f759a New helper: path_... |
2744 2745 2746 2747 2748 2749 2750 2751 2752 |
return 0; } if (mnt->mnt_parent == path2->mnt) break; mnt = mnt->mnt_parent; } dentry = mnt->mnt_mountpoint; } res = is_subdir(dentry, path2->dentry); |
99b7db7b8 fs: brlock vfsmou... |
2753 |
br_read_unlock(vfsmount_lock); |
2096f759a New helper: path_... |
2754 2755 2756 |
return res; } EXPORT_SYMBOL(path_is_under); |
1da177e4c Linux-2.6.12-rc2 |
2757 2758 |
void d_genocide(struct dentry *root) { |
949854d02 fs: Use rename lo... |
2759 |
struct dentry *this_parent; |
1da177e4c Linux-2.6.12-rc2 |
2760 |
struct list_head *next; |
949854d02 fs: Use rename lo... |
2761 |
unsigned seq; |
58db63d08 fs: dcache avoid ... |
2762 |
int locked = 0; |
1da177e4c Linux-2.6.12-rc2 |
2763 |
|
949854d02 fs: Use rename lo... |
2764 |
seq = read_seqbegin(&rename_lock); |
58db63d08 fs: dcache avoid ... |
2765 2766 |
again: this_parent = root; |
2fd6b7f50 fs: dcache scale ... |
2767 |
spin_lock(&this_parent->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
2768 2769 2770 2771 2772 |
repeat: next = this_parent->d_subdirs.next; resume: while (next != &this_parent->d_subdirs) { struct list_head *tmp = next; |
5160ee6fc [PATCH] shrink de... |
2773 |
struct dentry *dentry = list_entry(tmp, struct dentry, d_u.d_child); |
1da177e4c Linux-2.6.12-rc2 |
2774 |
next = tmp->next; |
949854d02 fs: Use rename lo... |
2775 |
|
da5029563 fs: dcache scale ... |
2776 2777 2778 |
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 |
2779 |
continue; |
da5029563 fs: dcache scale ... |
2780 |
} |
1da177e4c Linux-2.6.12-rc2 |
2781 |
if (!list_empty(&dentry->d_subdirs)) { |
2fd6b7f50 fs: dcache scale ... |
2782 2783 |
spin_unlock(&this_parent->d_lock); spin_release(&dentry->d_lock.dep_map, 1, _RET_IP_); |
1da177e4c Linux-2.6.12-rc2 |
2784 |
this_parent = dentry; |
2fd6b7f50 fs: dcache scale ... |
2785 |
spin_acquire(&this_parent->d_lock.dep_map, 0, 1, _RET_IP_); |
1da177e4c Linux-2.6.12-rc2 |
2786 2787 |
goto repeat; } |
949854d02 fs: Use rename lo... |
2788 2789 2790 2791 |
if (!(dentry->d_flags & DCACHE_GENOCIDE)) { dentry->d_flags |= DCACHE_GENOCIDE; dentry->d_count--; } |
b7ab39f63 fs: dcache scale ... |
2792 |
spin_unlock(&dentry->d_lock); |
1da177e4c Linux-2.6.12-rc2 |
2793 2794 |
} if (this_parent != root) { |
c826cb7df dcache.c: create ... |
2795 |
struct dentry *child = this_parent; |
949854d02 fs: Use rename lo... |
2796 2797 2798 2799 |
if (!(this_parent->d_flags & DCACHE_GENOCIDE)) { this_parent->d_flags |= DCACHE_GENOCIDE; this_parent->d_count--; } |
c826cb7df dcache.c: create ... |
2800 2801 |
this_parent = try_to_ascend(this_parent, locked, seq); if (!this_parent) |
949854d02 fs: Use rename lo... |
2802 |
goto rename_retry; |
949854d02 fs: Use rename lo... |
2803 |
next = child->d_u.d_child.next; |
1da177e4c Linux-2.6.12-rc2 |
2804 2805 |
goto resume; } |
2fd6b7f50 fs: dcache scale ... |
2806 |
spin_unlock(&this_parent->d_lock); |
58db63d08 fs: dcache avoid ... |
2807 |
if (!locked && read_seqretry(&rename_lock, seq)) |
949854d02 fs: Use rename lo... |
2808 |
goto rename_retry; |
58db63d08 fs: dcache avoid ... |
2809 2810 2811 2812 2813 2814 2815 2816 |
if (locked) write_sequnlock(&rename_lock); return; rename_retry: locked = 1; write_seqlock(&rename_lock); goto again; |
1da177e4c Linux-2.6.12-rc2 |
2817 2818 2819 2820 2821 2822 2823 2824 2825 2826 2827 2828 2829 2830 2831 2832 2833 2834 2835 2836 |
} /** * 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... |
2837 2838 |
dentry = d_hash_and_lookup(dir, name); if (dentry) { |
1da177e4c Linux-2.6.12-rc2 |
2839 2840 2841 2842 |
if (dentry->d_inode) ino = dentry->d_inode->i_ino; dput(dentry); } |
1da177e4c Linux-2.6.12-rc2 |
2843 2844 |
return ino; } |
ec4f86059 fs/dcache.c: Codi... |
2845 |
EXPORT_SYMBOL(find_inode_number); |
1da177e4c Linux-2.6.12-rc2 |
2846 2847 2848 2849 2850 2851 2852 2853 2854 2855 2856 2857 2858 2859 2860 2861 2862 2863 2864 2865 2866 2867 2868 |
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 '... |
2869 |
sizeof(struct hlist_bl_head), |
1da177e4c Linux-2.6.12-rc2 |
2870 2871 2872 2873 2874 2875 2876 2877 |
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 '... |
2878 |
INIT_HLIST_BL_HEAD(dentry_hashtable + loop); |
1da177e4c Linux-2.6.12-rc2 |
2879 |
} |
74bf17cff fs: remove the un... |
2880 |
static void __init dcache_init(void) |
1da177e4c Linux-2.6.12-rc2 |
2881 2882 2883 2884 2885 2886 2887 2888 |
{ 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... |
2889 2890 |
dentry_cache = KMEM_CACHE(dentry, SLAB_RECLAIM_ACCOUNT|SLAB_PANIC|SLAB_MEM_SPREAD); |
1da177e4c Linux-2.6.12-rc2 |
2891 2892 2893 2894 2895 2896 2897 |
/* 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 '... |
2898 |
sizeof(struct hlist_bl_head), |
1da177e4c Linux-2.6.12-rc2 |
2899 2900 2901 2902 2903 2904 2905 2906 |
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 '... |
2907 |
INIT_HLIST_BL_HEAD(dentry_hashtable + loop); |
1da177e4c Linux-2.6.12-rc2 |
2908 2909 2910 |
} /* SLAB cache for __getname() consumers */ |
e18b890bb [PATCH] slab: rem... |
2911 |
struct kmem_cache *names_cachep __read_mostly; |
ec4f86059 fs/dcache.c: Codi... |
2912 |
EXPORT_SYMBOL(names_cachep); |
1da177e4c Linux-2.6.12-rc2 |
2913 |
|
1da177e4c Linux-2.6.12-rc2 |
2914 |
EXPORT_SYMBOL(d_genocide); |
1da177e4c Linux-2.6.12-rc2 |
2915 2916 2917 2918 2919 2920 2921 2922 2923 2924 2925 2926 2927 2928 2929 2930 2931 |
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... |
2932 |
SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL); |
1da177e4c Linux-2.6.12-rc2 |
2933 |
|
74bf17cff fs: remove the un... |
2934 2935 |
dcache_init(); inode_init(); |
1da177e4c Linux-2.6.12-rc2 |
2936 |
files_init(mempages); |
74bf17cff fs: remove the un... |
2937 |
mnt_init(); |
1da177e4c Linux-2.6.12-rc2 |
2938 2939 2940 |
bdev_cache_init(); chrdev_init(); } |