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fs/dcache.c
62.1 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 "internal.h" |
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|
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int sysctl_vfs_cache_pressure __read_mostly = 100; |
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EXPORT_SYMBOL_GPL(sysctl_vfs_cache_pressure); __cacheline_aligned_in_smp DEFINE_SPINLOCK(dcache_lock); |
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__cacheline_aligned_in_smp DEFINE_SEQLOCK(rename_lock); |
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EXPORT_SYMBOL(dcache_lock); |
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static struct kmem_cache *dentry_cache __read_mostly; |
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#define DNAME_INLINE_LEN (sizeof(struct dentry)-offsetof(struct dentry,d_iname)) /* * 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; static struct hlist_head *dentry_hashtable __read_mostly; |
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/* Statistics gathering. */ struct dentry_stat_t dentry_stat = { .age_limit = 45, }; |
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static void __d_free(struct dentry *dentry) |
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{ |
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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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static void d_callback(struct rcu_head *head) { struct dentry * dentry = container_of(head, struct dentry, d_u.d_rcu); __d_free(dentry); } |
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/* * no dcache_lock, please. The caller must decrement dentry_stat.nr_dentry * inside dcache_lock. */ static void d_free(struct dentry *dentry) { if (dentry->d_op && dentry->d_op->d_release) dentry->d_op->d_release(dentry); |
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/* if dentry was never inserted into hash, immediate free is OK */ |
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if (hlist_unhashed(&dentry->d_hash)) |
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__d_free(dentry); else call_rcu(&dentry->d_u.d_rcu, d_callback); |
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} /* * Release the dentry's inode, using the filesystem * d_iput() operation if defined. |
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*/ |
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static void dentry_iput(struct dentry * dentry) |
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__releases(dentry->d_lock) __releases(dcache_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); spin_unlock(&dcache_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); spin_unlock(&dcache_lock); } } |
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/* * dentry_lru_(add|add_tail|del|del_init) must be called with dcache_lock held. */ static void dentry_lru_add(struct dentry *dentry) { list_add(&dentry->d_lru, &dentry->d_sb->s_dentry_lru); dentry->d_sb->s_nr_dentry_unused++; dentry_stat.nr_unused++; } static void dentry_lru_add_tail(struct dentry *dentry) { list_add_tail(&dentry->d_lru, &dentry->d_sb->s_dentry_lru); dentry->d_sb->s_nr_dentry_unused++; dentry_stat.nr_unused++; } static void dentry_lru_del(struct dentry *dentry) { if (!list_empty(&dentry->d_lru)) { list_del(&dentry->d_lru); dentry->d_sb->s_nr_dentry_unused--; dentry_stat.nr_unused--; } } static void dentry_lru_del_init(struct dentry *dentry) { if (likely(!list_empty(&dentry->d_lru))) { list_del_init(&dentry->d_lru); dentry->d_sb->s_nr_dentry_unused--; dentry_stat.nr_unused--; } } |
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/** * d_kill - kill dentry and return parent * @dentry: dentry to kill * |
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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. */ static struct dentry *d_kill(struct dentry *dentry) |
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__releases(dentry->d_lock) __releases(dcache_lock) |
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{ struct dentry *parent; list_del(&dentry->d_u.d_child); dentry_stat.nr_dentry--; /* For d_free, below */ /*drops the locks, at that point nobody can reach this dentry */ dentry_iput(dentry); |
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if (IS_ROOT(dentry)) parent = NULL; else parent = dentry->d_parent; |
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d_free(dentry); |
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return parent; |
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} |
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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. * * no dcache lock, please. */ void dput(struct dentry *dentry) { if (!dentry) return; repeat: if (atomic_read(&dentry->d_count) == 1) might_sleep(); if (!atomic_dec_and_lock(&dentry->d_count, &dcache_lock)) return; spin_lock(&dentry->d_lock); if (atomic_read(&dentry->d_count)) { spin_unlock(&dentry->d_lock); spin_unlock(&dcache_lock); return; } /* * AV: ->d_delete() is _NOT_ allowed to block now. */ if (dentry->d_op && dentry->d_op->d_delete) { if (dentry->d_op->d_delete(dentry)) goto unhash_it; } /* Unreachable? Get rid of it */ if (d_unhashed(dentry)) goto kill_it; if (list_empty(&dentry->d_lru)) { dentry->d_flags |= DCACHE_REFERENCED; |
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dentry_lru_add(dentry); |
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} spin_unlock(&dentry->d_lock); spin_unlock(&dcache_lock); return; unhash_it: __d_drop(dentry); |
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kill_it: |
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/* if dentry was on the d_lru list delete it from there */ dentry_lru_del(dentry); |
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dentry = d_kill(dentry); if (dentry) goto repeat; |
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} |
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EXPORT_SYMBOL(dput); |
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/** * 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. */ spin_lock(&dcache_lock); if (d_unhashed(dentry)) { spin_unlock(&dcache_lock); return 0; } /* * Check whether to do a partial shrink_dcache * to get rid of unused child entries. */ if (!list_empty(&dentry->d_subdirs)) { spin_unlock(&dcache_lock); shrink_dcache_parent(dentry); spin_lock(&dcache_lock); } /* * 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). */ spin_lock(&dentry->d_lock); if (atomic_read(&dentry->d_count) > 1) { if (dentry->d_inode && S_ISDIR(dentry->d_inode->i_mode)) { spin_unlock(&dentry->d_lock); spin_unlock(&dcache_lock); return -EBUSY; } } __d_drop(dentry); spin_unlock(&dentry->d_lock); spin_unlock(&dcache_lock); return 0; } |
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EXPORT_SYMBOL(d_invalidate); |
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/* This should be called _only_ with dcache_lock held */ static inline struct dentry * __dget_locked(struct dentry *dentry) { atomic_inc(&dentry->d_count); |
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dentry_lru_del_init(dentry); |
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return dentry; } struct dentry * dget_locked(struct dentry *dentry) { return __dget_locked(dentry); } |
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EXPORT_SYMBOL(dget_locked); |
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/** * 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. * |
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* If the inode has an IS_ROOT, DCACHE_DISCONNECTED alias, then prefer |
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* any other hashed alias over that one unless @want_discon is set, |
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* in which case only return an IS_ROOT, DCACHE_DISCONNECTED alias. |
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*/ static struct dentry * __d_find_alias(struct inode *inode, int want_discon) { struct list_head *head, *next, *tmp; struct dentry *alias, *discon_alias=NULL; head = &inode->i_dentry; next = inode->i_dentry.next; while (next != head) { tmp = next; next = tmp->next; prefetch(next); alias = list_entry(tmp, struct dentry, d_alias); if (S_ISDIR(inode->i_mode) || !d_unhashed(alias)) { |
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if (IS_ROOT(alias) && (alias->d_flags & DCACHE_DISCONNECTED)) |
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discon_alias = alias; else if (!want_discon) { __dget_locked(alias); return alias; } } } if (discon_alias) __dget_locked(discon_alias); return discon_alias; } struct dentry * d_find_alias(struct inode *inode) { |
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struct dentry *de = NULL; if (!list_empty(&inode->i_dentry)) { spin_lock(&dcache_lock); de = __d_find_alias(inode, 0); spin_unlock(&dcache_lock); } |
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return de; } |
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EXPORT_SYMBOL(d_find_alias); |
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/* * Try to kill dentries associated with this inode. * WARNING: you must own a reference to inode. */ void d_prune_aliases(struct inode *inode) { |
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struct dentry *dentry; |
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restart: spin_lock(&dcache_lock); |
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list_for_each_entry(dentry, &inode->i_dentry, d_alias) { |
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spin_lock(&dentry->d_lock); if (!atomic_read(&dentry->d_count)) { __dget_locked(dentry); __d_drop(dentry); spin_unlock(&dentry->d_lock); spin_unlock(&dcache_lock); dput(dentry); goto restart; } spin_unlock(&dentry->d_lock); } spin_unlock(&dcache_lock); } |
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EXPORT_SYMBOL(d_prune_aliases); |
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/* |
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* Throw away a dentry - free the inode, dput the parent. This requires that * the LRU list has already been removed. * |
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* Try to prune ancestors as well. This is necessary to prevent * quadratic behavior of shrink_dcache_parent(), but is also expected * to be beneficial in reducing dentry cache fragmentation. |
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*/ |
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static void prune_one_dentry(struct dentry * dentry) |
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{ |
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__d_drop(dentry); |
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dentry = d_kill(dentry); |
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/* * Prune ancestors. Locking is simpler than in dput(), * because dcache_lock needs to be taken anyway. */ |
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spin_lock(&dcache_lock); |
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while (dentry) { if (!atomic_dec_and_lock(&dentry->d_count, &dentry->d_lock)) return; if (dentry->d_op && dentry->d_op->d_delete) dentry->d_op->d_delete(dentry); |
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dentry_lru_del_init(dentry); |
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__d_drop(dentry); dentry = d_kill(dentry); spin_lock(&dcache_lock); } |
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} |
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/* * Shrink the dentry LRU on a given superblock. * @sb : superblock to shrink dentry LRU. * @count: If count is NULL, we prune all dentries on superblock. * @flags: If flags is non-zero, we need to do special processing based on * which flags are set. This means we don't need to maintain multiple * similar copies of this loop. |
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*/ |
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static void __shrink_dcache_sb(struct super_block *sb, int *count, int flags) |
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{ |
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LIST_HEAD(referenced); LIST_HEAD(tmp); struct dentry *dentry; int cnt = 0; |
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BUG_ON(!sb); BUG_ON((flags & DCACHE_REFERENCED) && count == NULL); spin_lock(&dcache_lock); if (count != NULL) /* called from prune_dcache() and shrink_dcache_parent() */ cnt = *count; restart: if (count == NULL) list_splice_init(&sb->s_dentry_lru, &tmp); else { 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); spin_lock(&dentry->d_lock); /* * 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. |
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*/ |
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if ((flags & DCACHE_REFERENCED) && (dentry->d_flags & DCACHE_REFERENCED)) { dentry->d_flags &= ~DCACHE_REFERENCED; |
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list_move(&dentry->d_lru, &referenced); |
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spin_unlock(&dentry->d_lock); } else { list_move_tail(&dentry->d_lru, &tmp); spin_unlock(&dentry->d_lock); cnt--; if (!cnt) break; |
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} |
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cond_resched_lock(&dcache_lock); |
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} |
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} while (!list_empty(&tmp)) { dentry = list_entry(tmp.prev, struct dentry, d_lru); dentry_lru_del_init(dentry); spin_lock(&dentry->d_lock); |
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/* * We found an inuse dentry which was not removed from |
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* the LRU because of laziness during lookup. Do not free * it - just keep it off the LRU list. |
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*/ |
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if (atomic_read(&dentry->d_count)) { spin_unlock(&dentry->d_lock); |
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continue; } |
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prune_one_dentry(dentry); /* dentry->d_lock was dropped in prune_one_dentry() */ cond_resched_lock(&dcache_lock); } if (count == NULL && !list_empty(&sb->s_dentry_lru)) goto restart; if (count != NULL) *count = cnt; if (!list_empty(&referenced)) list_splice(&referenced, &sb->s_dentry_lru); spin_unlock(&dcache_lock); } /** * prune_dcache - shrink the dcache * @count: number of entries to try to free * * Shrink the dcache. This is done when we need more memory, or simply when we * need to unmount something (at which point we need to unuse all dentries). * * This function may fail to free any resources if all the dentries are in use. */ static void prune_dcache(int count) { |
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struct super_block *sb, *p = NULL; |
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int w_count; int unused = dentry_stat.nr_unused; int prune_ratio; int pruned; if (unused == 0 || count == 0) return; spin_lock(&dcache_lock); |
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if (count >= unused) prune_ratio = 1; else prune_ratio = unused / count; spin_lock(&sb_lock); |
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list_for_each_entry(sb, &super_blocks, s_list) { |
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if (list_empty(&sb->s_instances)) continue; |
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if (sb->s_nr_dentry_unused == 0) |
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continue; |
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sb->s_count++; /* Now, we reclaim unused dentrins with fairness. * We reclaim them same percentage from each superblock. * We calculate number of dentries to scan on this sb * as follows, but the implementation is arranged to avoid * overflows: * number of dentries to scan on this sb = * count * (number of dentries on this sb / * number of dentries in the machine) |
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*/ |
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spin_unlock(&sb_lock); if (prune_ratio != 1) w_count = (sb->s_nr_dentry_unused / prune_ratio) + 1; else w_count = sb->s_nr_dentry_unused; pruned = w_count; |
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/* |
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* We need to be sure this filesystem isn't being unmounted, * otherwise we could race with generic_shutdown_super(), and * end up holding a reference to an inode while the filesystem * is unmounted. So we try to get s_umount, and make sure * s_root isn't NULL. |
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*/ |
da3bbdd46 fix soft lock up ... |
571 572 573 574 575 576 577 578 |
if (down_read_trylock(&sb->s_umount)) { if ((sb->s_root != NULL) && (!list_empty(&sb->s_dentry_lru))) { spin_unlock(&dcache_lock); __shrink_dcache_sb(sb, &w_count, DCACHE_REFERENCED); pruned -= w_count; spin_lock(&dcache_lock); |
0feae5c47 [PATCH] Fix dcach... |
579 |
} |
da3bbdd46 fix soft lock up ... |
580 |
up_read(&sb->s_umount); |
0feae5c47 [PATCH] Fix dcach... |
581 |
} |
da3bbdd46 fix soft lock up ... |
582 |
spin_lock(&sb_lock); |
dca332528 no need for list_... |
583 584 |
if (p) __put_super(p); |
da3bbdd46 fix soft lock up ... |
585 |
count -= pruned; |
dca332528 no need for list_... |
586 |
p = sb; |
79893c17b fix prune_dcache(... |
587 588 589 |
/* more work left to do? */ if (count <= 0) break; |
1da177e4c Linux-2.6.12-rc2 |
590 |
} |
dca332528 no need for list_... |
591 592 |
if (p) __put_super(p); |
da3bbdd46 fix soft lock up ... |
593 |
spin_unlock(&sb_lock); |
1da177e4c Linux-2.6.12-rc2 |
594 595 |
spin_unlock(&dcache_lock); } |
1da177e4c Linux-2.6.12-rc2 |
596 597 598 599 600 601 602 603 |
/** * shrink_dcache_sb - shrink dcache for a superblock * @sb: superblock * * 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 |
604 605 |
void shrink_dcache_sb(struct super_block * sb) { |
da3bbdd46 fix soft lock up ... |
606 |
__shrink_dcache_sb(sb, NULL, 0); |
1da177e4c Linux-2.6.12-rc2 |
607 |
} |
ec4f86059 fs/dcache.c: Codi... |
608 |
EXPORT_SYMBOL(shrink_dcache_sb); |
1da177e4c Linux-2.6.12-rc2 |
609 610 |
/* |
c636ebdb1 [PATCH] VFS: Dest... |
611 612 613 614 615 616 617 |
* 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; |
f87135762 [PATCH] VFS: Fix ... |
618 |
unsigned detached = 0; |
c636ebdb1 [PATCH] VFS: Dest... |
619 620 621 622 623 |
BUG_ON(!IS_ROOT(dentry)); /* detach this root from the system */ spin_lock(&dcache_lock); |
da3bbdd46 fix soft lock up ... |
624 |
dentry_lru_del_init(dentry); |
c636ebdb1 [PATCH] VFS: Dest... |
625 626 627 628 629 630 631 632 633 634 635 636 637 |
__d_drop(dentry); spin_unlock(&dcache_lock); for (;;) { /* descend to the first leaf in the current subtree */ while (!list_empty(&dentry->d_subdirs)) { struct dentry *loop; /* this is a branch with children - detach all of them * from the system in one go */ spin_lock(&dcache_lock); list_for_each_entry(loop, &dentry->d_subdirs, d_u.d_child) { |
da3bbdd46 fix soft lock up ... |
638 |
dentry_lru_del_init(loop); |
c636ebdb1 [PATCH] VFS: Dest... |
639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 |
__d_drop(loop); cond_resched_lock(&dcache_lock); } spin_unlock(&dcache_lock); /* move to the first child */ dentry = list_entry(dentry->d_subdirs.next, struct dentry, d_u.d_child); } /* consume the dentries from this leaf up through its parents * until we find one with children or run out altogether */ do { struct inode *inode; if (atomic_read(&dentry->d_count) != 0) { 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, atomic_read(&dentry->d_count), dentry->d_sb->s_type->name, dentry->d_sb->s_id); BUG(); } |
871c0067d [PATCH vfs-2.6 1/... |
669 |
if (IS_ROOT(dentry)) |
c636ebdb1 [PATCH] VFS: Dest... |
670 |
parent = NULL; |
871c0067d [PATCH vfs-2.6 1/... |
671 672 |
else { parent = dentry->d_parent; |
c636ebdb1 [PATCH] VFS: Dest... |
673 |
atomic_dec(&parent->d_count); |
871c0067d [PATCH vfs-2.6 1/... |
674 |
} |
c636ebdb1 [PATCH] VFS: Dest... |
675 676 |
list_del(&dentry->d_u.d_child); |
f87135762 [PATCH] VFS: Fix ... |
677 |
detached++; |
c636ebdb1 [PATCH] VFS: Dest... |
678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 |
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) |
f87135762 [PATCH] VFS: Fix ... |
695 |
goto out; |
c636ebdb1 [PATCH] VFS: Dest... |
696 697 698 699 700 701 702 703 |
dentry = parent; } while (list_empty(&dentry->d_subdirs)); dentry = list_entry(dentry->d_subdirs.next, struct dentry, d_u.d_child); } |
f87135762 [PATCH] VFS: Fix ... |
704 705 706 707 708 |
out: /* several dentries were freed, need to correct nr_dentry */ spin_lock(&dcache_lock); dentry_stat.nr_dentry -= detached; spin_unlock(&dcache_lock); |
c636ebdb1 [PATCH] VFS: Dest... |
709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 |
} /* * destroy the dentries attached to a superblock on unmounting * - we don't need to use dentry->d_lock, and only need dcache_lock when * removing the dentry from the system lists and hashes because: * - 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; atomic_dec(&dentry->d_count); shrink_dcache_for_umount_subtree(dentry); while (!hlist_empty(&sb->s_anon)) { dentry = hlist_entry(sb->s_anon.first, struct dentry, d_hash); shrink_dcache_for_umount_subtree(dentry); } } /* |
1da177e4c Linux-2.6.12-rc2 |
741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 |
* 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 */ int have_submounts(struct dentry *parent) { struct dentry *this_parent = parent; struct list_head *next; spin_lock(&dcache_lock); if (d_mountpoint(parent)) goto positive; repeat: next = this_parent->d_subdirs.next; resume: while (next != &this_parent->d_subdirs) { struct list_head *tmp = next; |
5160ee6fc [PATCH] shrink de... |
767 |
struct dentry *dentry = list_entry(tmp, struct dentry, d_u.d_child); |
1da177e4c Linux-2.6.12-rc2 |
768 769 770 771 772 773 774 775 776 777 778 779 780 |
next = tmp->next; /* Have we found a mount point ? */ if (d_mountpoint(dentry)) goto positive; if (!list_empty(&dentry->d_subdirs)) { this_parent = dentry; goto repeat; } } /* * All done at this level ... ascend and resume the search. */ if (this_parent != parent) { |
5160ee6fc [PATCH] shrink de... |
781 |
next = this_parent->d_u.d_child.next; |
1da177e4c Linux-2.6.12-rc2 |
782 783 784 785 786 787 788 789 790 |
this_parent = this_parent->d_parent; goto resume; } spin_unlock(&dcache_lock); return 0; /* No mount points found in tree */ positive: spin_unlock(&dcache_lock); return 1; } |
ec4f86059 fs/dcache.c: Codi... |
791 |
EXPORT_SYMBOL(have_submounts); |
1da177e4c Linux-2.6.12-rc2 |
792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 |
/* * 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) { struct dentry *this_parent = parent; struct list_head *next; int found = 0; spin_lock(&dcache_lock); repeat: next = this_parent->d_subdirs.next; resume: while (next != &this_parent->d_subdirs) { struct list_head *tmp = next; |
5160ee6fc [PATCH] shrink de... |
819 |
struct dentry *dentry = list_entry(tmp, struct dentry, d_u.d_child); |
1da177e4c Linux-2.6.12-rc2 |
820 |
next = tmp->next; |
da3bbdd46 fix soft lock up ... |
821 |
dentry_lru_del_init(dentry); |
1da177e4c Linux-2.6.12-rc2 |
822 823 824 825 826 |
/* * move only zero ref count dentries to the end * of the unused list for prune_dcache */ if (!atomic_read(&dentry->d_count)) { |
da3bbdd46 fix soft lock up ... |
827 |
dentry_lru_add_tail(dentry); |
1da177e4c Linux-2.6.12-rc2 |
828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 |
found++; } /* * We can return to the caller if we have found some (this * ensures forward progress). We'll be coming back to find * the rest. */ if (found && need_resched()) goto out; /* * Descend a level if the d_subdirs list is non-empty. */ if (!list_empty(&dentry->d_subdirs)) { this_parent = dentry; |
1da177e4c Linux-2.6.12-rc2 |
844 845 846 847 848 849 850 |
goto repeat; } } /* * All done at this level ... ascend and resume the search. */ if (this_parent != parent) { |
5160ee6fc [PATCH] shrink de... |
851 |
next = this_parent->d_u.d_child.next; |
1da177e4c Linux-2.6.12-rc2 |
852 |
this_parent = this_parent->d_parent; |
1da177e4c Linux-2.6.12-rc2 |
853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 |
goto resume; } out: spin_unlock(&dcache_lock); return found; } /** * 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 ... |
869 |
struct super_block *sb = parent->d_sb; |
1da177e4c Linux-2.6.12-rc2 |
870 871 872 |
int found; while ((found = select_parent(parent)) != 0) |
da3bbdd46 fix soft lock up ... |
873 |
__shrink_dcache_sb(sb, &found, 0); |
1da177e4c Linux-2.6.12-rc2 |
874 |
} |
ec4f86059 fs/dcache.c: Codi... |
875 |
EXPORT_SYMBOL(shrink_dcache_parent); |
1da177e4c Linux-2.6.12-rc2 |
876 |
|
1da177e4c Linux-2.6.12-rc2 |
877 878 879 880 881 882 883 884 885 886 887 888 |
/* * Scan `nr' dentries and return the number which remain. * * We need to avoid reentering the filesystem if the caller is performing a * GFP_NOFS allocation attempt. One example deadlock is: * * ext2_new_block->getblk->GFP->shrink_dcache_memory->prune_dcache-> * prune_one_dentry->dput->dentry_iput->iput->inode->i_sb->s_op->put_inode-> * ext2_discard_prealloc->ext2_free_blocks->lock_super->DEADLOCK. * * In this case we return -1 to tell the caller that we baled. */ |
7f8275d0d mm: add context a... |
889 |
static int shrink_dcache_memory(struct shrinker *shrink, int nr, gfp_t gfp_mask) |
1da177e4c Linux-2.6.12-rc2 |
890 891 892 893 |
{ if (nr) { if (!(gfp_mask & __GFP_FS)) return -1; |
da3bbdd46 fix soft lock up ... |
894 |
prune_dcache(nr); |
1da177e4c Linux-2.6.12-rc2 |
895 896 897 |
} return (dentry_stat.nr_unused / 100) * sysctl_vfs_cache_pressure; } |
8e1f936b7 mm: clean up and ... |
898 899 900 901 |
static struct shrinker dcache_shrinker = { .shrink = shrink_dcache_memory, .seeks = DEFAULT_SEEKS, }; |
1da177e4c Linux-2.6.12-rc2 |
902 903 904 905 906 907 908 909 910 911 912 913 914 915 |
/** * 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; char *dname; |
e12ba74d8 Group short-lived... |
916 |
dentry = kmem_cache_alloc(dentry_cache, GFP_KERNEL); |
1da177e4c Linux-2.6.12-rc2 |
917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 |
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; atomic_set(&dentry->d_count, 1); dentry->d_flags = DCACHE_UNHASHED; spin_lock_init(&dentry->d_lock); dentry->d_inode = NULL; dentry->d_parent = NULL; dentry->d_sb = NULL; dentry->d_op = NULL; dentry->d_fsdata = NULL; dentry->d_mounted = 0; |
1da177e4c Linux-2.6.12-rc2 |
945 946 947 948 949 950 951 952 953 |
INIT_HLIST_NODE(&dentry->d_hash); INIT_LIST_HEAD(&dentry->d_lru); INIT_LIST_HEAD(&dentry->d_subdirs); INIT_LIST_HEAD(&dentry->d_alias); if (parent) { dentry->d_parent = dget(parent); dentry->d_sb = parent->d_sb; } else { |
5160ee6fc [PATCH] shrink de... |
954 |
INIT_LIST_HEAD(&dentry->d_u.d_child); |
1da177e4c Linux-2.6.12-rc2 |
955 956 957 958 |
} spin_lock(&dcache_lock); if (parent) |
5160ee6fc [PATCH] shrink de... |
959 |
list_add(&dentry->d_u.d_child, &parent->d_subdirs); |
1da177e4c Linux-2.6.12-rc2 |
960 961 962 963 964 |
dentry_stat.nr_dentry++; spin_unlock(&dcache_lock); return dentry; } |
ec4f86059 fs/dcache.c: Codi... |
965 |
EXPORT_SYMBOL(d_alloc); |
1da177e4c Linux-2.6.12-rc2 |
966 967 968 969 970 971 972 973 974 975 |
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... |
976 |
EXPORT_SYMBOL(d_alloc_name); |
1da177e4c Linux-2.6.12-rc2 |
977 |
|
360da9002 [PATCH vfs-2.6 3/... |
978 979 980 981 982 983 984 985 |
/* the caller must hold dcache_lock */ static void __d_instantiate(struct dentry *dentry, struct inode *inode) { if (inode) list_add(&dentry->d_alias, &inode->i_dentry); dentry->d_inode = inode; fsnotify_d_instantiate(dentry, inode); } |
1da177e4c Linux-2.6.12-rc2 |
986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 |
/** * 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... |
1003 |
BUG_ON(!list_empty(&entry->d_alias)); |
1da177e4c Linux-2.6.12-rc2 |
1004 |
spin_lock(&dcache_lock); |
360da9002 [PATCH vfs-2.6 3/... |
1005 |
__d_instantiate(entry, inode); |
1da177e4c Linux-2.6.12-rc2 |
1006 1007 1008 |
spin_unlock(&dcache_lock); security_d_instantiate(entry, inode); } |
ec4f86059 fs/dcache.c: Codi... |
1009 |
EXPORT_SYMBOL(d_instantiate); |
1da177e4c Linux-2.6.12-rc2 |
1010 1011 1012 1013 1014 1015 1016 1017 |
/** * 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... |
1018 |
* aliased dentry instead and drop one reference to inode. |
1da177e4c Linux-2.6.12-rc2 |
1019 1020 1021 |
* * Note that in order to avoid conflicts with rename() etc, the caller * had better be holding the parent directory semaphore. |
e866cfa93 [PATCH] d_instant... |
1022 1023 1024 1025 |
* * 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 |
1026 |
*/ |
770bfad84 NFS: Add dentry m... |
1027 1028 |
static struct dentry *__d_instantiate_unique(struct dentry *entry, struct inode *inode) |
1da177e4c Linux-2.6.12-rc2 |
1029 1030 1031 1032 1033 |
{ 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... |
1034 |
if (!inode) { |
360da9002 [PATCH vfs-2.6 3/... |
1035 |
__d_instantiate(entry, NULL); |
770bfad84 NFS: Add dentry m... |
1036 1037 |
return NULL; } |
1da177e4c Linux-2.6.12-rc2 |
1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 |
list_for_each_entry(alias, &inode->i_dentry, d_alias) { struct qstr *qstr = &alias->d_name; if (qstr->hash != hash) continue; if (alias->d_parent != entry->d_parent) continue; if (qstr->len != len) continue; if (memcmp(qstr->name, name, len)) continue; dget_locked(alias); |
1da177e4c Linux-2.6.12-rc2 |
1050 1051 |
return alias; } |
770bfad84 NFS: Add dentry m... |
1052 |
|
360da9002 [PATCH vfs-2.6 3/... |
1053 |
__d_instantiate(entry, inode); |
1da177e4c Linux-2.6.12-rc2 |
1054 1055 |
return NULL; } |
770bfad84 NFS: Add dentry m... |
1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 |
struct dentry *d_instantiate_unique(struct dentry *entry, struct inode *inode) { struct dentry *result; BUG_ON(!list_empty(&entry->d_alias)); spin_lock(&dcache_lock); result = __d_instantiate_unique(entry, inode); spin_unlock(&dcache_lock); if (!result) { security_d_instantiate(entry, inode); return NULL; } BUG_ON(!d_unhashed(result)); iput(inode); return result; } |
1da177e4c Linux-2.6.12-rc2 |
1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 |
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 }; res = d_alloc(NULL, &name); if (res) { res->d_sb = root_inode->i_sb; res->d_parent = res; d_instantiate(res, root_inode); } } return res; } |
ec4f86059 fs/dcache.c: Codi... |
1103 |
EXPORT_SYMBOL(d_alloc_root); |
1da177e4c Linux-2.6.12-rc2 |
1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 |
static inline struct hlist_head *d_hash(struct dentry *parent, 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); } /** |
4ea3ada29 [PATCH] new helpe... |
1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 |
* 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... |
1126 1127 1128 1129 |
* 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... |
1130 1131 1132 |
*/ struct dentry *d_obtain_alias(struct inode *inode) { |
9308a6128 [PATCH] kill d_al... |
1133 1134 1135 |
static const struct qstr anonstring = { .name = "" }; struct dentry *tmp; struct dentry *res; |
4ea3ada29 [PATCH] new helpe... |
1136 1137 |
if (!inode) |
440037287 [PATCH] switch al... |
1138 |
return ERR_PTR(-ESTALE); |
4ea3ada29 [PATCH] new helpe... |
1139 1140 |
if (IS_ERR(inode)) return ERR_CAST(inode); |
9308a6128 [PATCH] kill d_al... |
1141 1142 1143 1144 1145 1146 1147 1148 |
res = d_find_alias(inode); if (res) goto out_iput; tmp = d_alloc(NULL, &anonstring); if (!tmp) { res = ERR_PTR(-ENOMEM); goto out_iput; |
4ea3ada29 [PATCH] new helpe... |
1149 |
} |
9308a6128 [PATCH] kill d_al... |
1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 |
tmp->d_parent = tmp; /* make sure dput doesn't croak */ spin_lock(&dcache_lock); res = __d_find_alias(inode, 0); if (res) { spin_unlock(&dcache_lock); dput(tmp); goto out_iput; } /* attach a disconnected dentry */ spin_lock(&tmp->d_lock); tmp->d_sb = inode->i_sb; tmp->d_inode = inode; tmp->d_flags |= DCACHE_DISCONNECTED; tmp->d_flags &= ~DCACHE_UNHASHED; list_add(&tmp->d_alias, &inode->i_dentry); hlist_add_head(&tmp->d_hash, &inode->i_sb->s_anon); spin_unlock(&tmp->d_lock); spin_unlock(&dcache_lock); return tmp; out_iput: iput(inode); return res; |
4ea3ada29 [PATCH] new helpe... |
1176 |
} |
adc487204 EXPORT_SYMBOL(d_o... |
1177 |
EXPORT_SYMBOL(d_obtain_alias); |
1da177e4c Linux-2.6.12-rc2 |
1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 |
/** * 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; |
21c0d8fdd [PATCH] knfsd: cl... |
1198 |
if (inode && S_ISDIR(inode->i_mode)) { |
1da177e4c Linux-2.6.12-rc2 |
1199 1200 1201 1202 1203 1204 |
spin_lock(&dcache_lock); new = __d_find_alias(inode, 1); if (new) { BUG_ON(!(new->d_flags & DCACHE_DISCONNECTED)); spin_unlock(&dcache_lock); security_d_instantiate(new, inode); |
1da177e4c Linux-2.6.12-rc2 |
1205 1206 1207 |
d_move(new, dentry); iput(inode); } else { |
360da9002 [PATCH vfs-2.6 3/... |
1208 1209 |
/* already taking dcache_lock, so d_add() by hand */ __d_instantiate(dentry, inode); |
1da177e4c Linux-2.6.12-rc2 |
1210 1211 1212 1213 1214 1215 1216 1217 |
spin_unlock(&dcache_lock); security_d_instantiate(dentry, inode); d_rehash(dentry); } } else d_add(dentry, inode); return new; } |
ec4f86059 fs/dcache.c: Codi... |
1218 |
EXPORT_SYMBOL(d_splice_alias); |
1da177e4c Linux-2.6.12-rc2 |
1219 |
|
9403540c0 dcache: Add case-... |
1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 |
/** * 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_... |
1236 |
struct dentry *d_add_ci(struct dentry *dentry, struct inode *inode, |
9403540c0 dcache: Add case-... |
1237 1238 1239 1240 1241 |
struct qstr *name) { int error; struct dentry *found; struct dentry *new; |
b6520c819 cleanup d_add_ci |
1242 1243 1244 1245 |
/* * First check if a dentry matching the name already exists, * if not go ahead and create it now. */ |
9403540c0 dcache: Add case-... |
1246 |
found = d_hash_and_lookup(dentry->d_parent, name); |
9403540c0 dcache: Add case-... |
1247 1248 1249 1250 1251 1252 |
if (!found) { new = d_alloc(dentry->d_parent, name); if (!new) { error = -ENOMEM; goto err_out; } |
b6520c819 cleanup d_add_ci |
1253 |
|
9403540c0 dcache: Add case-... |
1254 1255 1256 1257 1258 1259 1260 |
found = d_splice_alias(inode, new); if (found) { dput(new); return found; } return new; } |
b6520c819 cleanup d_add_ci |
1261 1262 1263 1264 1265 1266 1267 |
/* * 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-... |
1268 1269 1270 1271 1272 1273 |
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-... |
1274 1275 1276 |
iput(inode); return found; } |
b6520c819 cleanup d_add_ci |
1277 |
|
9403540c0 dcache: Add case-... |
1278 1279 |
/* * Negative dentry: instantiate it unless the inode is a directory and |
b6520c819 cleanup d_add_ci |
1280 |
* already has a dentry. |
9403540c0 dcache: Add case-... |
1281 |
*/ |
9403540c0 dcache: Add case-... |
1282 |
spin_lock(&dcache_lock); |
b6520c819 cleanup d_add_ci |
1283 |
if (!S_ISDIR(inode->i_mode) || list_empty(&inode->i_dentry)) { |
360da9002 [PATCH vfs-2.6 3/... |
1284 |
__d_instantiate(found, inode); |
9403540c0 dcache: Add case-... |
1285 1286 1287 1288 |
spin_unlock(&dcache_lock); security_d_instantiate(found, inode); return found; } |
b6520c819 cleanup d_add_ci |
1289 |
|
9403540c0 dcache: Add case-... |
1290 |
/* |
b6520c819 cleanup d_add_ci |
1291 1292 |
* In case a directory already has a (disconnected) entry grab a * reference to it, move it in place and use it. |
9403540c0 dcache: Add case-... |
1293 1294 1295 1296 |
*/ new = list_entry(inode->i_dentry.next, struct dentry, d_alias); dget_locked(new); spin_unlock(&dcache_lock); |
9403540c0 dcache: Add case-... |
1297 |
security_d_instantiate(found, inode); |
9403540c0 dcache: Add case-... |
1298 |
d_move(new, found); |
9403540c0 dcache: Add case-... |
1299 |
iput(inode); |
9403540c0 dcache: Add case-... |
1300 |
dput(found); |
9403540c0 dcache: Add case-... |
1301 1302 1303 1304 1305 1306 |
return new; err_out: iput(inode); return ERR_PTR(error); } |
ec4f86059 fs/dcache.c: Codi... |
1307 |
EXPORT_SYMBOL(d_add_ci); |
1da177e4c Linux-2.6.12-rc2 |
1308 1309 1310 1311 1312 |
/** * d_lookup - search for a dentry * @parent: parent dentry * @name: qstr of name we wish to find |
b04f784e5 fs: remove extra ... |
1313 |
* Returns: dentry, or NULL |
1da177e4c Linux-2.6.12-rc2 |
1314 |
* |
b04f784e5 fs: remove extra ... |
1315 1316 1317 1318 |
* 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 |
1319 |
*/ |
1da177e4c Linux-2.6.12-rc2 |
1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 |
struct dentry * d_lookup(struct dentry * parent, struct qstr * name) { struct dentry * dentry = NULL; unsigned long seq; 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... |
1333 |
EXPORT_SYMBOL(d_lookup); |
1da177e4c Linux-2.6.12-rc2 |
1334 |
|
b04f784e5 fs: remove extra ... |
1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 |
/* * __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. */ |
1da177e4c Linux-2.6.12-rc2 |
1350 1351 1352 1353 1354 1355 1356 1357 |
struct dentry * __d_lookup(struct dentry * parent, struct qstr * name) { unsigned int len = name->len; unsigned int hash = name->hash; const unsigned char *str = name->name; struct hlist_head *head = d_hash(parent,hash); struct dentry *found = NULL; struct hlist_node *node; |
665a7583f [PATCH] Remove hl... |
1358 |
struct dentry *dentry; |
1da177e4c Linux-2.6.12-rc2 |
1359 |
|
b04f784e5 fs: remove extra ... |
1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 |
/* * 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. * * See Documentation/vfs/dcache-locking.txt for more details. */ |
1da177e4c Linux-2.6.12-rc2 |
1373 1374 |
rcu_read_lock(); |
665a7583f [PATCH] Remove hl... |
1375 |
hlist_for_each_entry_rcu(dentry, node, head, d_hash) { |
1da177e4c Linux-2.6.12-rc2 |
1376 |
struct qstr *qstr; |
1da177e4c Linux-2.6.12-rc2 |
1377 1378 1379 1380 1381 1382 1383 1384 1385 |
if (dentry->d_name.hash != hash) continue; if (dentry->d_parent != parent) continue; spin_lock(&dentry->d_lock); /* * Recheck the dentry after taking the lock - d_move may have |
b04f784e5 fs: remove extra ... |
1386 1387 |
* changed things. Don't bother checking the hash because * we're about to compare the whole name anyway. |
1da177e4c Linux-2.6.12-rc2 |
1388 1389 1390 |
*/ if (dentry->d_parent != parent) goto next; |
d0185c088 Fix NULL pointer ... |
1391 1392 1393 |
/* non-existing due to RCU? */ if (d_unhashed(dentry)) goto next; |
1da177e4c Linux-2.6.12-rc2 |
1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 |
/* * It is safe to compare names since d_move() cannot * change the qstr (protected by d_lock). */ qstr = &dentry->d_name; if (parent->d_op && parent->d_op->d_compare) { if (parent->d_op->d_compare(parent, qstr, name)) goto next; } else { if (qstr->len != len) goto next; if (memcmp(qstr->name, str, len)) goto next; } |
d0185c088 Fix NULL pointer ... |
1408 1409 |
atomic_inc(&dentry->d_count); found = dentry; |
1da177e4c Linux-2.6.12-rc2 |
1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 |
spin_unlock(&dentry->d_lock); break; next: spin_unlock(&dentry->d_lock); } rcu_read_unlock(); return found; } /** |
3e7e241f8 [PATCH] dcache: A... |
1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 |
* 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); if (dir->d_op && dir->d_op->d_hash) { if (dir->d_op->d_hash(dir, name) < 0) goto out; } dentry = d_lookup(dir, name); out: return dentry; } /** |
1da177e4c Linux-2.6.12-rc2 |
1447 1448 1449 |
* d_validate - verify dentry provided from insecure source * @dentry: The dentry alleged to be valid child of @dparent * @dparent: The parent dentry (known to be valid) |
1da177e4c Linux-2.6.12-rc2 |
1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 |
* * 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. */ int d_validate(struct dentry *dentry, struct dentry *dparent) { struct hlist_head *base; struct hlist_node *lhp; /* Check whether the ptr might be valid at all.. */ if (!kmem_ptr_validate(dentry_cache, dentry)) goto out; if (dentry->d_parent != dparent) goto out; spin_lock(&dcache_lock); base = d_hash(dparent, dentry->d_name.hash); hlist_for_each(lhp,base) { |
665a7583f [PATCH] Remove hl... |
1471 |
/* hlist_for_each_entry_rcu() not required for d_hash list |
1da177e4c Linux-2.6.12-rc2 |
1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 |
* as it is parsed under dcache_lock */ if (dentry == hlist_entry(lhp, struct dentry, d_hash)) { __dget_locked(dentry); spin_unlock(&dcache_lock); return 1; } } spin_unlock(&dcache_lock); out: return 0; } |
ec4f86059 fs/dcache.c: Codi... |
1484 |
EXPORT_SYMBOL(d_validate); |
1da177e4c Linux-2.6.12-rc2 |
1485 1486 1487 1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 |
/* * 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) { |
7a91bf7f5 [PATCH] fsnotify_... |
1509 |
int isdir = 0; |
1da177e4c Linux-2.6.12-rc2 |
1510 1511 1512 1513 1514 |
/* * Are we the only user? */ spin_lock(&dcache_lock); spin_lock(&dentry->d_lock); |
7a91bf7f5 [PATCH] fsnotify_... |
1515 |
isdir = S_ISDIR(dentry->d_inode->i_mode); |
1da177e4c Linux-2.6.12-rc2 |
1516 |
if (atomic_read(&dentry->d_count) == 1) { |
13e3c5e5b clean DCACHE_CANT... |
1517 |
dentry->d_flags &= ~DCACHE_CANT_MOUNT; |
1da177e4c Linux-2.6.12-rc2 |
1518 |
dentry_iput(dentry); |
7a91bf7f5 [PATCH] fsnotify_... |
1519 |
fsnotify_nameremove(dentry, isdir); |
1da177e4c Linux-2.6.12-rc2 |
1520 1521 1522 1523 1524 1525 1526 1527 |
return; } if (!d_unhashed(dentry)) __d_drop(dentry); spin_unlock(&dentry->d_lock); spin_unlock(&dcache_lock); |
7a91bf7f5 [PATCH] fsnotify_... |
1528 1529 |
fsnotify_nameremove(dentry, isdir); |
1da177e4c Linux-2.6.12-rc2 |
1530 |
} |
ec4f86059 fs/dcache.c: Codi... |
1531 |
EXPORT_SYMBOL(d_delete); |
1da177e4c Linux-2.6.12-rc2 |
1532 1533 1534 1535 1536 1537 1538 |
static void __d_rehash(struct dentry * entry, struct hlist_head *list) { entry->d_flags &= ~DCACHE_UNHASHED; hlist_add_head_rcu(&entry->d_hash, list); } |
770bfad84 NFS: Add dentry m... |
1539 1540 1541 1542 |
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 |
1543 1544 1545 1546 1547 1548 1549 1550 1551 |
/** * 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 |
1552 1553 |
spin_lock(&dcache_lock); spin_lock(&entry->d_lock); |
770bfad84 NFS: Add dentry m... |
1554 |
_d_rehash(entry); |
1da177e4c Linux-2.6.12-rc2 |
1555 1556 1557 |
spin_unlock(&entry->d_lock); spin_unlock(&dcache_lock); } |
ec4f86059 fs/dcache.c: Codi... |
1558 |
EXPORT_SYMBOL(d_rehash); |
1da177e4c Linux-2.6.12-rc2 |
1559 |
|
1da177e4c Linux-2.6.12-rc2 |
1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 |
/* * 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.. */ 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... |
1578 |
swap(target->d_name.name, dentry->d_name.name); |
1da177e4c Linux-2.6.12-rc2 |
1579 1580 1581 1582 1583 |
} else { /* * dentry:internal, target:external. Steal target's * storage and make target internal. */ |
321bcf921 dcache: don't exp... |
1584 1585 |
memcpy(target->d_iname, dentry->d_name.name, dentry->d_name.len + 1); |
1da177e4c Linux-2.6.12-rc2 |
1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 |
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(... |
1605 1606 |
dentry->d_name.len = target->d_name.len; return; |
1da177e4c Linux-2.6.12-rc2 |
1607 1608 |
} } |
9a8d5bb4a generic swap(): d... |
1609 |
swap(dentry->d_name.len, target->d_name.len); |
1da177e4c Linux-2.6.12-rc2 |
1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 |
} /* * We cannibalize "target" when moving dentry on top of it, * because it's going to be thrown away anyway. We could be more * polite about it, though. * * This forceful removal will result in ugly /proc output if * somebody holds a file open that got deleted due to a rename. * We could be nicer about the deleted file, and let it show |
bc154b1ef dcache: trivial c... |
1620 1621 |
* up under the name it had before it was deleted rather than * under the original name of the file that was moved on top of it. |
1da177e4c Linux-2.6.12-rc2 |
1622 1623 |
*/ |
9eaef27b3 [PATCH] VFS: Make... |
1624 1625 |
/* * d_move_locked - move a dentry |
1da177e4c Linux-2.6.12-rc2 |
1626 1627 1628 1629 1630 1631 |
* @dentry: entry to move * @target: new dentry * * Update the dcache to reflect the move of a file name. Negative * dcache entries should not be moved in this way. */ |
9eaef27b3 [PATCH] VFS: Make... |
1632 |
static void d_move_locked(struct dentry * dentry, struct dentry * target) |
1da177e4c Linux-2.6.12-rc2 |
1633 1634 1635 1636 1637 1638 |
{ struct hlist_head *list; if (!dentry->d_inode) printk(KERN_WARNING "VFS: moving negative dcache entry "); |
1da177e4c Linux-2.6.12-rc2 |
1639 1640 1641 1642 1643 1644 |
write_seqlock(&rename_lock); /* * XXXX: do we really need to take target->d_lock? */ if (target < dentry) { spin_lock(&target->d_lock); |
a90b9c05d [PATCH] lockdep: ... |
1645 |
spin_lock_nested(&dentry->d_lock, DENTRY_D_LOCK_NESTED); |
1da177e4c Linux-2.6.12-rc2 |
1646 1647 |
} else { spin_lock(&dentry->d_lock); |
a90b9c05d [PATCH] lockdep: ... |
1648 |
spin_lock_nested(&target->d_lock, DENTRY_D_LOCK_NESTED); |
1da177e4c Linux-2.6.12-rc2 |
1649 1650 1651 |
} /* Move the dentry to the target hash queue, if on different bucket */ |
f77e34987 vfs: use the pred... |
1652 |
if (d_unhashed(dentry)) |
1da177e4c Linux-2.6.12-rc2 |
1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 |
goto already_unhashed; hlist_del_rcu(&dentry->d_hash); already_unhashed: list = d_hash(target->d_parent, target->d_name.hash); __d_rehash(dentry, list); /* Unhash the target: dput() will then get rid of it */ __d_drop(target); |
5160ee6fc [PATCH] shrink de... |
1663 1664 |
list_del(&dentry->d_u.d_child); list_del(&target->d_u.d_child); |
1da177e4c Linux-2.6.12-rc2 |
1665 1666 1667 |
/* Switch the names.. */ switch_names(dentry, target); |
9a8d5bb4a generic swap(): d... |
1668 |
swap(dentry->d_name.hash, target->d_name.hash); |
1da177e4c Linux-2.6.12-rc2 |
1669 1670 1671 1672 1673 |
/* ... and switch the parents */ if (IS_ROOT(dentry)) { dentry->d_parent = target->d_parent; target->d_parent = target; |
5160ee6fc [PATCH] shrink de... |
1674 |
INIT_LIST_HEAD(&target->d_u.d_child); |
1da177e4c Linux-2.6.12-rc2 |
1675 |
} else { |
9a8d5bb4a generic swap(): d... |
1676 |
swap(dentry->d_parent, target->d_parent); |
1da177e4c Linux-2.6.12-rc2 |
1677 1678 |
/* And add them back to the (new) parent lists */ |
5160ee6fc [PATCH] shrink de... |
1679 |
list_add(&target->d_u.d_child, &target->d_parent->d_subdirs); |
1da177e4c Linux-2.6.12-rc2 |
1680 |
} |
5160ee6fc [PATCH] shrink de... |
1681 |
list_add(&dentry->d_u.d_child, &dentry->d_parent->d_subdirs); |
1da177e4c Linux-2.6.12-rc2 |
1682 |
spin_unlock(&target->d_lock); |
c32ccd87b [PATCH] inotify: ... |
1683 |
fsnotify_d_move(dentry); |
1da177e4c Linux-2.6.12-rc2 |
1684 1685 |
spin_unlock(&dentry->d_lock); write_sequnlock(&rename_lock); |
9eaef27b3 [PATCH] VFS: Make... |
1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 |
} /** * d_move - move a dentry * @dentry: entry to move * @target: new dentry * * Update the dcache to reflect the move of a file name. Negative * dcache entries should not be moved in this way. */ void d_move(struct dentry * dentry, struct dentry * target) { spin_lock(&dcache_lock); d_move_locked(dentry, target); |
1da177e4c Linux-2.6.12-rc2 |
1701 1702 |
spin_unlock(&dcache_lock); } |
ec4f86059 fs/dcache.c: Codi... |
1703 |
EXPORT_SYMBOL(d_move); |
1da177e4c Linux-2.6.12-rc2 |
1704 |
|
e2761a116 [PATCH vfs-2.6 2/... |
1705 1706 1707 1708 1709 1710 1711 |
/** * 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... |
1712 |
*/ |
e2761a116 [PATCH vfs-2.6 2/... |
1713 |
struct dentry *d_ancestor(struct dentry *p1, struct dentry *p2) |
9eaef27b3 [PATCH] VFS: Make... |
1714 1715 |
{ struct dentry *p; |
871c0067d [PATCH vfs-2.6 1/... |
1716 |
for (p = p2; !IS_ROOT(p); p = p->d_parent) { |
9eaef27b3 [PATCH] VFS: Make... |
1717 |
if (p->d_parent == p1) |
e2761a116 [PATCH vfs-2.6 2/... |
1718 |
return p; |
9eaef27b3 [PATCH] VFS: Make... |
1719 |
} |
e2761a116 [PATCH vfs-2.6 2/... |
1720 |
return NULL; |
9eaef27b3 [PATCH] VFS: Make... |
1721 1722 1723 1724 1725 1726 1727 1728 1729 1730 |
} /* * This helper attempts to cope with remotely renamed directories * * It assumes that the caller is already holding * dentry->d_parent->d_inode->i_mutex and the dcache_lock * * Note: If ever the locking in lock_rename() changes, then please * remember to update this too... |
9eaef27b3 [PATCH] VFS: Make... |
1731 1732 |
*/ static struct dentry *__d_unalias(struct dentry *dentry, struct dentry *alias) |
31f3e0b3a [patch 1/3] vfs: ... |
1733 |
__releases(dcache_lock) |
9eaef27b3 [PATCH] VFS: Make... |
1734 1735 1736 1737 1738 1739 1740 1741 1742 1743 |
{ 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; /* Check for loops */ ret = ERR_PTR(-ELOOP); |
e2761a116 [PATCH vfs-2.6 2/... |
1744 |
if (d_ancestor(alias, dentry)) |
9eaef27b3 [PATCH] VFS: Make... |
1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756 1757 1758 1759 1760 1761 1762 1763 1764 1765 1766 1767 |
goto out_err; /* 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: d_move_locked(alias, dentry); ret = alias; out_err: spin_unlock(&dcache_lock); if (m2) mutex_unlock(m2); if (m1) mutex_unlock(m1); return ret; } /* |
770bfad84 NFS: Add dentry m... |
1768 1769 1770 1771 1772 1773 1774 1775 |
* Prepare an anonymous dentry for life in the superblock's dentry tree as a * named dentry in place of the dentry to be replaced. */ static void __d_materialise_dentry(struct dentry *dentry, struct dentry *anon) { struct dentry *dparent, *aparent; switch_names(dentry, anon); |
9a8d5bb4a generic swap(): d... |
1776 |
swap(dentry->d_name.hash, anon->d_name.hash); |
770bfad84 NFS: Add dentry m... |
1777 1778 1779 1780 1781 1782 1783 1784 1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 1806 1807 |
dparent = dentry->d_parent; aparent = anon->d_parent; 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); 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 * root directory alias in its place if there is one */ struct dentry *d_materialise_unique(struct dentry *dentry, struct inode *inode) { |
9eaef27b3 [PATCH] VFS: Make... |
1808 |
struct dentry *actual; |
770bfad84 NFS: Add dentry m... |
1809 1810 1811 1812 1813 1814 1815 |
BUG_ON(!d_unhashed(dentry)); spin_lock(&dcache_lock); if (!inode) { actual = dentry; |
360da9002 [PATCH vfs-2.6 3/... |
1816 |
__d_instantiate(dentry, NULL); |
770bfad84 NFS: Add dentry m... |
1817 1818 |
goto found_lock; } |
9eaef27b3 [PATCH] VFS: Make... |
1819 1820 1821 1822 1823 1824 1825 1826 1827 1828 1829 1830 1831 1832 1833 1834 1835 1836 1837 1838 1839 |
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; /* Is this an anonymous mountpoint that we could splice * into our tree? */ if (IS_ROOT(alias)) { spin_lock(&alias->d_lock); __d_materialise_dentry(dentry, alias); __d_drop(alias); goto found; } /* Nope, but we must(!) avoid directory aliasing */ actual = __d_unalias(dentry, alias); if (IS_ERR(actual)) dput(alias); goto out_nolock; } |
770bfad84 NFS: Add dentry m... |
1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 |
} /* Add a unique reference */ actual = __d_instantiate_unique(dentry, inode); if (!actual) actual = dentry; else if (unlikely(!d_unhashed(actual))) goto shouldnt_be_hashed; found_lock: spin_lock(&actual->d_lock); found: _d_rehash(actual); spin_unlock(&actual->d_lock); spin_unlock(&dcache_lock); |
9eaef27b3 [PATCH] VFS: Make... |
1855 |
out_nolock: |
770bfad84 NFS: Add dentry m... |
1856 1857 1858 1859 1860 1861 1862 |
if (actual == dentry) { security_d_instantiate(dentry, inode); return NULL; } iput(inode); return actual; |
770bfad84 NFS: Add dentry m... |
1863 1864 1865 |
shouldnt_be_hashed: spin_unlock(&dcache_lock); BUG(); |
770bfad84 NFS: Add dentry m... |
1866 |
} |
ec4f86059 fs/dcache.c: Codi... |
1867 |
EXPORT_SYMBOL_GPL(d_materialise_unique); |
770bfad84 NFS: Add dentry m... |
1868 |
|
cdd16d026 [patch 2/3] vfs: ... |
1869 |
static int prepend(char **buffer, int *buflen, const char *str, int namelen) |
6092d0481 [patch 1/7] vfs: ... |
1870 1871 1872 1873 1874 1875 1876 1877 |
{ *buflen -= namelen; if (*buflen < 0) return -ENAMETOOLONG; *buffer -= namelen; memcpy(*buffer, str, namelen); return 0; } |
cdd16d026 [patch 2/3] vfs: ... |
1878 1879 1880 1881 |
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 |
1882 |
/** |
f2eb6575d vfs: add prepend_... |
1883 1884 |
* Prepend path string to a buffer * |
9d1bc6013 [patch 2/7] vfs: ... |
1885 1886 |
* @path: the dentry/vfsmount to report * @root: root vfsmnt/dentry (may be modified by this function) |
f2eb6575d vfs: add prepend_... |
1887 1888 |
* @buffer: pointer to the end of the buffer * @buflen: pointer to buffer length |
552ce544e Revert "[PATCH] F... |
1889 |
* |
f2eb6575d vfs: add prepend_... |
1890 |
* Caller holds the dcache_lock. |
9d1bc6013 [patch 2/7] vfs: ... |
1891 1892 1893 |
* * 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 |
1894 |
*/ |
f2eb6575d vfs: add prepend_... |
1895 1896 |
static int prepend_path(const struct path *path, struct path *root, char **buffer, int *buflen) |
1da177e4c Linux-2.6.12-rc2 |
1897 |
{ |
9d1bc6013 [patch 2/7] vfs: ... |
1898 1899 |
struct dentry *dentry = path->dentry; struct vfsmount *vfsmnt = path->mnt; |
f2eb6575d vfs: add prepend_... |
1900 1901 |
bool slash = false; int error = 0; |
6092d0481 [patch 1/7] vfs: ... |
1902 |
|
99b7db7b8 fs: brlock vfsmou... |
1903 |
br_read_lock(vfsmount_lock); |
f2eb6575d vfs: add prepend_... |
1904 |
while (dentry != root->dentry || vfsmnt != root->mnt) { |
1da177e4c Linux-2.6.12-rc2 |
1905 |
struct dentry * parent; |
1da177e4c Linux-2.6.12-rc2 |
1906 |
if (dentry == vfsmnt->mnt_root || IS_ROOT(dentry)) { |
552ce544e Revert "[PATCH] F... |
1907 |
/* Global root? */ |
1da177e4c Linux-2.6.12-rc2 |
1908 |
if (vfsmnt->mnt_parent == vfsmnt) { |
1da177e4c Linux-2.6.12-rc2 |
1909 1910 1911 1912 |
goto global_root; } dentry = vfsmnt->mnt_mountpoint; vfsmnt = vfsmnt->mnt_parent; |
1da177e4c Linux-2.6.12-rc2 |
1913 1914 1915 1916 |
continue; } parent = dentry->d_parent; prefetch(parent); |
f2eb6575d vfs: add prepend_... |
1917 1918 1919 1920 1921 1922 1923 |
error = prepend_name(buffer, buflen, &dentry->d_name); if (!error) error = prepend(buffer, buflen, "/", 1); if (error) break; slash = true; |
1da177e4c Linux-2.6.12-rc2 |
1924 1925 |
dentry = parent; } |
be285c712 [patch 3/3] vfs: ... |
1926 |
out: |
f2eb6575d vfs: add prepend_... |
1927 1928 |
if (!error && !slash) error = prepend(buffer, buflen, "/", 1); |
99b7db7b8 fs: brlock vfsmou... |
1929 |
br_read_unlock(vfsmount_lock); |
f2eb6575d vfs: add prepend_... |
1930 |
return error; |
1da177e4c Linux-2.6.12-rc2 |
1931 1932 |
global_root: |
98dc568bc vfs: __d_path: do... |
1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 |
/* * 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: ... |
1943 1944 |
root->mnt = vfsmnt; root->dentry = dentry; |
be285c712 [patch 3/3] vfs: ... |
1945 |
goto out; |
f2eb6575d vfs: add prepend_... |
1946 |
} |
be285c712 [patch 3/3] vfs: ... |
1947 |
|
f2eb6575d vfs: add prepend_... |
1948 1949 1950 1951 |
/** * __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... |
1952 |
* @buf: buffer to return value in |
f2eb6575d vfs: add prepend_... |
1953 1954 |
* @buflen: buffer length * |
ffd1f4ed5 vfs: only add " (... |
1955 |
* Convert a dentry into an ASCII path name. |
f2eb6575d vfs: add prepend_... |
1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 |
* * Returns a pointer into the buffer or an error code if the * path was too long. * * "buflen" should be positive. Caller holds the dcache_lock. * * 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); |
f2eb6575d vfs: add prepend_... |
1972 1973 1974 1975 1976 |
error = prepend_path(path, root, &res, &buflen); if (error) return ERR_PTR(error); return res; |
1da177e4c Linux-2.6.12-rc2 |
1977 |
} |
ffd1f4ed5 vfs: only add " (... |
1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 |
/* * 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... |
1993 1994 1995 1996 |
static int prepend_unreachable(char **buffer, int *buflen) { return prepend(buffer, buflen, "(unreachable)", 13); } |
a03a8a709 d_path: kerneldoc... |
1997 1998 |
/** * d_path - return the path of a dentry |
cf28b4863 d_path: Make d_pa... |
1999 |
* @path: path to report |
a03a8a709 d_path: kerneldoc... |
2000 2001 2002 2003 2004 2005 |
* @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... |
2006 2007 2008 2009 |
* 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... |
2010 |
* |
31f3e0b3a [patch 1/3] vfs: ... |
2011 |
* "buflen" should be positive. |
a03a8a709 d_path: kerneldoc... |
2012 |
*/ |
20d4fdc1a [patch 2/4] fs: m... |
2013 |
char *d_path(const struct path *path, char *buf, int buflen) |
1da177e4c Linux-2.6.12-rc2 |
2014 |
{ |
ffd1f4ed5 vfs: only add " (... |
2015 |
char *res = buf + buflen; |
6ac08c39a Use struct path i... |
2016 |
struct path root; |
9d1bc6013 [patch 2/7] vfs: ... |
2017 |
struct path tmp; |
ffd1f4ed5 vfs: only add " (... |
2018 |
int error; |
1da177e4c Linux-2.6.12-rc2 |
2019 |
|
c23fbb6bc VFS: delay the de... |
2020 2021 2022 2023 2024 2025 2026 |
/* * 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... |
2027 2028 |
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... |
2029 |
|
f7ad3c6be vfs: add helpers ... |
2030 |
get_fs_root(current->fs, &root); |
552ce544e Revert "[PATCH] F... |
2031 |
spin_lock(&dcache_lock); |
9d1bc6013 [patch 2/7] vfs: ... |
2032 |
tmp = root; |
ffd1f4ed5 vfs: only add " (... |
2033 2034 2035 |
error = path_with_deleted(path, &tmp, &res, &buflen); if (error) res = ERR_PTR(error); |
552ce544e Revert "[PATCH] F... |
2036 |
spin_unlock(&dcache_lock); |
6ac08c39a Use struct path i... |
2037 |
path_put(&root); |
1da177e4c Linux-2.6.12-rc2 |
2038 2039 |
return res; } |
ec4f86059 fs/dcache.c: Codi... |
2040 |
EXPORT_SYMBOL(d_path); |
1da177e4c Linux-2.6.12-rc2 |
2041 |
|
8df9d1a41 vfs: show unreach... |
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 |
/** * 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); spin_lock(&dcache_lock); tmp = root; error = path_with_deleted(path, &tmp, &res, &buflen); if (!error && !path_equal(&tmp, &root)) error = prepend_unreachable(&res, &buflen); spin_unlock(&dcache_lock); path_put(&root); if (error) res = ERR_PTR(error); return res; } |
1da177e4c Linux-2.6.12-rc2 |
2074 |
/* |
c23fbb6bc VFS: delay the de... |
2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093 2094 2095 |
* 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: ... |
2096 2097 |
* Write full pathname from the root of the filesystem into the buffer. */ |
c103135c1 new helper: __den... |
2098 |
char *__dentry_path(struct dentry *dentry, char *buf, int buflen) |
6092d0481 [patch 1/7] vfs: ... |
2099 2100 2101 |
{ char *end = buf + buflen; char *retval; |
6092d0481 [patch 1/7] vfs: ... |
2102 |
prepend(&end, &buflen, "\0", 1); |
6092d0481 [patch 1/7] vfs: ... |
2103 2104 2105 2106 2107 |
if (buflen < 1) goto Elong; /* Get '/' right */ retval = end-1; *retval = '/'; |
cdd16d026 [patch 2/3] vfs: ... |
2108 2109 |
while (!IS_ROOT(dentry)) { struct dentry *parent = dentry->d_parent; |
6092d0481 [patch 1/7] vfs: ... |
2110 |
|
6092d0481 [patch 1/7] vfs: ... |
2111 |
prefetch(parent); |
cdd16d026 [patch 2/3] vfs: ... |
2112 |
if ((prepend_name(&end, &buflen, &dentry->d_name) != 0) || |
6092d0481 [patch 1/7] vfs: ... |
2113 2114 2115 2116 2117 2118 |
(prepend(&end, &buflen, "/", 1) != 0)) goto Elong; retval = end; dentry = parent; } |
c103135c1 new helper: __den... |
2119 2120 2121 2122 2123 2124 2125 2126 2127 2128 2129 2130 2131 2132 2133 2134 2135 2136 2137 |
return retval; Elong: return ERR_PTR(-ENAMETOOLONG); } EXPORT_SYMBOL(__dentry_path); char *dentry_path(struct dentry *dentry, char *buf, int buflen) { char *p = NULL; char *retval; spin_lock(&dcache_lock); if (d_unlinked(dentry)) { p = buf + buflen; if (prepend(&p, &buflen, "//deleted", 10) != 0) goto Elong; buflen++; } retval = __dentry_path(dentry, buf, buflen); |
6092d0481 [patch 1/7] vfs: ... |
2138 |
spin_unlock(&dcache_lock); |
c103135c1 new helper: __den... |
2139 2140 |
if (!IS_ERR(retval) && p) *p = '/'; /* restore '/' overriden with '\0' */ |
6092d0481 [patch 1/7] vfs: ... |
2141 2142 2143 2144 2145 2146 2147 |
return retval; Elong: spin_unlock(&dcache_lock); return ERR_PTR(-ENAMETOOLONG); } /* |
1da177e4c Linux-2.6.12-rc2 |
2148 2149 2150 2151 2152 2153 2154 2155 2156 2157 2158 2159 2160 2161 2162 2163 2164 |
* 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... |
2165 |
SYSCALL_DEFINE2(getcwd, char __user *, buf, unsigned long, size) |
1da177e4c Linux-2.6.12-rc2 |
2166 |
{ |
552ce544e Revert "[PATCH] F... |
2167 |
int error; |
6ac08c39a Use struct path i... |
2168 |
struct path pwd, root; |
552ce544e Revert "[PATCH] F... |
2169 |
char *page = (char *) __get_free_page(GFP_USER); |
1da177e4c Linux-2.6.12-rc2 |
2170 2171 2172 |
if (!page) return -ENOMEM; |
f7ad3c6be vfs: add helpers ... |
2173 |
get_fs_root_and_pwd(current->fs, &root, &pwd); |
1da177e4c Linux-2.6.12-rc2 |
2174 |
|
552ce544e Revert "[PATCH] F... |
2175 |
error = -ENOENT; |
552ce544e Revert "[PATCH] F... |
2176 |
spin_lock(&dcache_lock); |
f3da392e9 dcache: extrace a... |
2177 |
if (!d_unlinked(pwd.dentry)) { |
552ce544e Revert "[PATCH] F... |
2178 |
unsigned long len; |
9d1bc6013 [patch 2/7] vfs: ... |
2179 |
struct path tmp = root; |
8df9d1a41 vfs: show unreach... |
2180 2181 |
char *cwd = page + PAGE_SIZE; int buflen = PAGE_SIZE; |
1da177e4c Linux-2.6.12-rc2 |
2182 |
|
8df9d1a41 vfs: show unreach... |
2183 2184 |
prepend(&cwd, &buflen, "\0", 1); error = prepend_path(&pwd, &tmp, &cwd, &buflen); |
552ce544e Revert "[PATCH] F... |
2185 |
spin_unlock(&dcache_lock); |
8df9d1a41 vfs: show unreach... |
2186 |
if (error) |
552ce544e Revert "[PATCH] F... |
2187 |
goto out; |
8df9d1a41 vfs: show unreach... |
2188 2189 2190 2191 2192 2193 |
/* Unreachable from current root */ if (!path_equal(&tmp, &root)) { error = prepend_unreachable(&cwd, &buflen); if (error) goto out; } |
552ce544e Revert "[PATCH] F... |
2194 2195 2196 2197 2198 2199 2200 2201 2202 |
error = -ERANGE; len = PAGE_SIZE + page - cwd; if (len <= size) { error = len; if (copy_to_user(buf, cwd, len)) error = -EFAULT; } } else spin_unlock(&dcache_lock); |
1da177e4c Linux-2.6.12-rc2 |
2203 2204 |
out: |
6ac08c39a Use struct path i... |
2205 2206 |
path_put(&pwd); path_put(&root); |
1da177e4c Linux-2.6.12-rc2 |
2207 2208 2209 2210 2211 2212 2213 2214 2215 2216 2217 2218 2219 2220 2221 2222 2223 2224 2225 2226 |
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/... |
2227 |
int is_subdir(struct dentry *new_dentry, struct dentry *old_dentry) |
1da177e4c Linux-2.6.12-rc2 |
2228 2229 |
{ int result; |
1da177e4c Linux-2.6.12-rc2 |
2230 |
unsigned long seq; |
e2761a116 [PATCH vfs-2.6 2/... |
2231 2232 2233 2234 2235 2236 |
if (new_dentry == old_dentry) return 1; /* * Need rcu_readlock to protect against the d_parent trashing * due to d_move |
1da177e4c Linux-2.6.12-rc2 |
2237 2238 |
*/ rcu_read_lock(); |
e2761a116 [PATCH vfs-2.6 2/... |
2239 |
do { |
1da177e4c Linux-2.6.12-rc2 |
2240 |
/* for restarting inner loop in case of seq retry */ |
1da177e4c Linux-2.6.12-rc2 |
2241 |
seq = read_seqbegin(&rename_lock); |
e2761a116 [PATCH vfs-2.6 2/... |
2242 |
if (d_ancestor(old_dentry, new_dentry)) |
1da177e4c Linux-2.6.12-rc2 |
2243 |
result = 1; |
e2761a116 [PATCH vfs-2.6 2/... |
2244 2245 |
else result = 0; |
1da177e4c Linux-2.6.12-rc2 |
2246 2247 2248 2249 2250 |
} while (read_seqretry(&rename_lock, seq)); rcu_read_unlock(); return result; } |
2096f759a New helper: path_... |
2251 2252 2253 2254 2255 |
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... |
2256 2257 |
br_read_lock(vfsmount_lock); |
2096f759a New helper: path_... |
2258 2259 2260 |
if (mnt != path2->mnt) { for (;;) { if (mnt->mnt_parent == mnt) { |
99b7db7b8 fs: brlock vfsmou... |
2261 |
br_read_unlock(vfsmount_lock); |
2096f759a New helper: path_... |
2262 2263 2264 2265 2266 2267 2268 2269 2270 |
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... |
2271 |
br_read_unlock(vfsmount_lock); |
2096f759a New helper: path_... |
2272 2273 2274 |
return res; } EXPORT_SYMBOL(path_is_under); |
1da177e4c Linux-2.6.12-rc2 |
2275 2276 2277 2278 2279 2280 2281 2282 2283 2284 2285 |
void d_genocide(struct dentry *root) { struct dentry *this_parent = root; struct list_head *next; spin_lock(&dcache_lock); repeat: next = this_parent->d_subdirs.next; resume: while (next != &this_parent->d_subdirs) { struct list_head *tmp = next; |
5160ee6fc [PATCH] shrink de... |
2286 |
struct dentry *dentry = list_entry(tmp, struct dentry, d_u.d_child); |
1da177e4c Linux-2.6.12-rc2 |
2287 2288 2289 2290 2291 2292 2293 2294 2295 2296 |
next = tmp->next; if (d_unhashed(dentry)||!dentry->d_inode) continue; if (!list_empty(&dentry->d_subdirs)) { this_parent = dentry; goto repeat; } atomic_dec(&dentry->d_count); } if (this_parent != root) { |
5160ee6fc [PATCH] shrink de... |
2297 |
next = this_parent->d_u.d_child.next; |
1da177e4c Linux-2.6.12-rc2 |
2298 2299 2300 2301 2302 2303 2304 2305 2306 2307 2308 2309 2310 2311 2312 2313 2314 2315 2316 2317 2318 2319 2320 2321 2322 |
atomic_dec(&this_parent->d_count); this_parent = this_parent->d_parent; goto resume; } spin_unlock(&dcache_lock); } /** * 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... |
2323 2324 |
dentry = d_hash_and_lookup(dir, name); if (dentry) { |
1da177e4c Linux-2.6.12-rc2 |
2325 2326 2327 2328 |
if (dentry->d_inode) ino = dentry->d_inode->i_ino; dput(dentry); } |
1da177e4c Linux-2.6.12-rc2 |
2329 2330 |
return ino; } |
ec4f86059 fs/dcache.c: Codi... |
2331 |
EXPORT_SYMBOL(find_inode_number); |
1da177e4c Linux-2.6.12-rc2 |
2332 2333 2334 2335 2336 2337 2338 2339 2340 2341 2342 2343 2344 2345 2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356 2357 2358 2359 2360 2361 2362 2363 2364 2365 |
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", sizeof(struct hlist_head), dhash_entries, 13, HASH_EARLY, &d_hash_shift, &d_hash_mask, 0); for (loop = 0; loop < (1 << d_hash_shift); loop++) INIT_HLIST_HEAD(&dentry_hashtable[loop]); } |
74bf17cff fs: remove the un... |
2366 |
static void __init dcache_init(void) |
1da177e4c Linux-2.6.12-rc2 |
2367 2368 2369 2370 2371 2372 2373 2374 |
{ 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... |
2375 2376 |
dentry_cache = KMEM_CACHE(dentry, SLAB_RECLAIM_ACCOUNT|SLAB_PANIC|SLAB_MEM_SPREAD); |
1da177e4c Linux-2.6.12-rc2 |
2377 |
|
8e1f936b7 mm: clean up and ... |
2378 |
register_shrinker(&dcache_shrinker); |
1da177e4c Linux-2.6.12-rc2 |
2379 2380 2381 2382 2383 2384 2385 2386 2387 2388 2389 2390 2391 2392 2393 2394 2395 2396 2397 2398 |
/* Hash may have been set up in dcache_init_early */ if (!hashdist) return; dentry_hashtable = alloc_large_system_hash("Dentry cache", sizeof(struct hlist_head), dhash_entries, 13, 0, &d_hash_shift, &d_hash_mask, 0); for (loop = 0; loop < (1 << d_hash_shift); loop++) INIT_HLIST_HEAD(&dentry_hashtable[loop]); } /* SLAB cache for __getname() consumers */ |
e18b890bb [PATCH] slab: rem... |
2399 |
struct kmem_cache *names_cachep __read_mostly; |
ec4f86059 fs/dcache.c: Codi... |
2400 |
EXPORT_SYMBOL(names_cachep); |
1da177e4c Linux-2.6.12-rc2 |
2401 |
|
1da177e4c Linux-2.6.12-rc2 |
2402 |
EXPORT_SYMBOL(d_genocide); |
1da177e4c Linux-2.6.12-rc2 |
2403 2404 2405 2406 2407 2408 2409 2410 2411 2412 2413 2414 2415 2416 2417 2418 2419 |
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... |
2420 |
SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL); |
1da177e4c Linux-2.6.12-rc2 |
2421 |
|
74bf17cff fs: remove the un... |
2422 2423 |
dcache_init(); inode_init(); |
1da177e4c Linux-2.6.12-rc2 |
2424 |
files_init(mempages); |
74bf17cff fs: remove the un... |
2425 |
mnt_init(); |
1da177e4c Linux-2.6.12-rc2 |
2426 2427 2428 |
bdev_cache_init(); chrdev_init(); } |