From da5029563a0a026c64821b09e8e7b4fd81d3fe1b Mon Sep 17 00:00:00 2001 From: Nick Piggin Date: Fri, 7 Jan 2011 17:49:33 +1100 Subject: fs: dcache scale d_unhashed Protect d_unhashed(dentry) condition with d_lock. This means keeping DCACHE_UNHASHED bit in synch with hash manipulations. Signed-off-by: Nick Piggin --- drivers/usb/core/inode.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'drivers/usb') diff --git a/drivers/usb/core/inode.c b/drivers/usb/core/inode.c index b690aa35df9a..e3ab4437ea96 100644 --- a/drivers/usb/core/inode.c +++ b/drivers/usb/core/inode.c @@ -347,10 +347,13 @@ static int usbfs_empty (struct dentry *dentry) list_for_each(list, &dentry->d_subdirs) { struct dentry *de = list_entry(list, struct dentry, d_u.d_child); + spin_lock(&de->d_lock); if (usbfs_positive(de)) { + spin_unlock(&de->d_lock); spin_unlock(&dcache_lock); return 0; } + spin_unlock(&de->d_lock); } spin_unlock(&dcache_lock); -- cgit v1.2.3 From 2fd6b7f50797f2e993eea59e0a0b8c6399c811dc Mon Sep 17 00:00:00 2001 From: Nick Piggin Date: Fri, 7 Jan 2011 17:49:34 +1100 Subject: fs: dcache scale subdirs Protect d_subdirs and d_child with d_lock, except in filesystems that aren't using dcache_lock for these anyway (eg. using i_mutex). Note: if we change the locking rule in future so that ->d_child protection is provided only with ->d_parent->d_lock, it may allow us to reduce some locking. But it would be an exception to an otherwise regular locking scheme, so we'd have to see some good results. Probably not worthwhile. Signed-off-by: Nick Piggin --- drivers/staging/smbfs/cache.c | 4 + drivers/usb/core/inode.c | 8 +- fs/autofs4/autofs_i.h | 11 ++ fs/autofs4/expire.c | 127 ++++++++++----------- fs/autofs4/root.c | 18 ++- fs/ceph/dir.c | 6 +- fs/ceph/inode.c | 8 +- fs/coda/cache.c | 2 + fs/dcache.c | 248 +++++++++++++++++++++++++++++------------- fs/libfs.c | 24 +++- fs/ncpfs/dir.c | 3 + fs/ncpfs/ncplib_kernel.h | 4 + fs/notify/fsnotify.c | 4 +- include/linux/dcache.h | 1 + kernel/cgroup.c | 19 +++- security/selinux/selinuxfs.c | 12 +- 16 files changed, 339 insertions(+), 160 deletions(-) (limited to 'drivers/usb') diff --git a/drivers/staging/smbfs/cache.c b/drivers/staging/smbfs/cache.c index 0beded260b00..920434b6c071 100644 --- a/drivers/staging/smbfs/cache.c +++ b/drivers/staging/smbfs/cache.c @@ -63,6 +63,7 @@ smb_invalidate_dircache_entries(struct dentry *parent) struct dentry *dentry; spin_lock(&dcache_lock); + spin_lock(&parent->d_lock); next = parent->d_subdirs.next; while (next != &parent->d_subdirs) { dentry = list_entry(next, struct dentry, d_u.d_child); @@ -70,6 +71,7 @@ smb_invalidate_dircache_entries(struct dentry *parent) smb_age_dentry(server, dentry); next = next->next; } + spin_unlock(&parent->d_lock); spin_unlock(&dcache_lock); } @@ -97,6 +99,7 @@ smb_dget_fpos(struct dentry *dentry, struct dentry *parent, unsigned long fpos) /* If a pointer is invalid, we search the dentry. */ spin_lock(&dcache_lock); + spin_lock(&parent->d_lock); next = parent->d_subdirs.next; while (next != &parent->d_subdirs) { dent = list_entry(next, struct dentry, d_u.d_child); @@ -111,6 +114,7 @@ smb_dget_fpos(struct dentry *dentry, struct dentry *parent, unsigned long fpos) } dent = NULL; out_unlock: + spin_unlock(&parent->d_lock); spin_unlock(&dcache_lock); return dent; } diff --git a/drivers/usb/core/inode.c b/drivers/usb/core/inode.c index e3ab4437ea96..89a0e8366585 100644 --- a/drivers/usb/core/inode.c +++ b/drivers/usb/core/inode.c @@ -344,18 +344,20 @@ static int usbfs_empty (struct dentry *dentry) struct list_head *list; spin_lock(&dcache_lock); - + spin_lock(&dentry->d_lock); list_for_each(list, &dentry->d_subdirs) { struct dentry *de = list_entry(list, struct dentry, d_u.d_child); - spin_lock(&de->d_lock); + + spin_lock_nested(&de->d_lock, DENTRY_D_LOCK_NESTED); if (usbfs_positive(de)) { spin_unlock(&de->d_lock); + spin_unlock(&dentry->d_lock); spin_unlock(&dcache_lock); return 0; } spin_unlock(&de->d_lock); } - + spin_unlock(&dentry->d_lock); spin_unlock(&dcache_lock); return 1; } diff --git a/fs/autofs4/autofs_i.h b/fs/autofs4/autofs_i.h index 3912dcf047e5..9d2ae9b30d9f 100644 --- a/fs/autofs4/autofs_i.h +++ b/fs/autofs4/autofs_i.h @@ -254,6 +254,17 @@ static inline int simple_positive(struct dentry *dentry) return dentry->d_inode && !d_unhashed(dentry); } +static inline void __autofs4_add_expiring(struct dentry *dentry) +{ + struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb); + struct autofs_info *ino = autofs4_dentry_ino(dentry); + if (ino) { + if (list_empty(&ino->expiring)) + list_add(&ino->expiring, &sbi->expiring_list); + } + return; +} + static inline void autofs4_add_expiring(struct dentry *dentry) { struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb); diff --git a/fs/autofs4/expire.c b/fs/autofs4/expire.c index ee6402050f13..968c1434af62 100644 --- a/fs/autofs4/expire.c +++ b/fs/autofs4/expire.c @@ -91,24 +91,64 @@ done: } /* - * Calculate next entry in top down tree traversal. - * From next_mnt in namespace.c - elegant. + * Calculate and dget next entry in top down tree traversal. */ -static struct dentry *next_dentry(struct dentry *p, struct dentry *root) +static struct dentry *get_next_positive_dentry(struct dentry *prev, + struct dentry *root) { - struct list_head *next = p->d_subdirs.next; + struct list_head *next; + struct dentry *p, *ret; + + if (prev == NULL) + return dget(prev); + spin_lock(&dcache_lock); +relock: + p = prev; + spin_lock(&p->d_lock); +again: + next = p->d_subdirs.next; if (next == &p->d_subdirs) { while (1) { - if (p == root) + struct dentry *parent; + + if (p == root) { + spin_unlock(&p->d_lock); + spin_unlock(&dcache_lock); + dput(prev); return NULL; + } + + parent = p->d_parent; + if (!spin_trylock(&parent->d_lock)) { + spin_unlock(&p->d_lock); + cpu_relax(); + goto relock; + } + spin_unlock(&p->d_lock); next = p->d_u.d_child.next; - if (next != &p->d_parent->d_subdirs) + p = parent; + if (next != &parent->d_subdirs) break; - p = p->d_parent; } } - return list_entry(next, struct dentry, d_u.d_child); + ret = list_entry(next, struct dentry, d_u.d_child); + + spin_lock_nested(&ret->d_lock, DENTRY_D_LOCK_NESTED); + /* Negative dentry - try next */ + if (!simple_positive(ret)) { + spin_unlock(&ret->d_lock); + p = ret; + goto again; + } + dget_dlock(ret); + spin_unlock(&ret->d_lock); + spin_unlock(&p->d_lock); + spin_unlock(&dcache_lock); + + dput(prev); + + return ret; } /* @@ -158,22 +198,11 @@ static int autofs4_tree_busy(struct vfsmount *mnt, if (!simple_positive(top)) return 1; - spin_lock(&dcache_lock); - for (p = top; p; p = next_dentry(p, top)) { - spin_lock(&p->d_lock); - /* Negative dentry - give up */ - if (!simple_positive(p)) { - spin_unlock(&p->d_lock); - continue; - } - + p = NULL; + while ((p = get_next_positive_dentry(p, top))) { DPRINTK("dentry %p %.*s", p, (int) p->d_name.len, p->d_name.name); - p = dget_dlock(p); - spin_unlock(&p->d_lock); - spin_unlock(&dcache_lock); - /* * Is someone visiting anywhere in the subtree ? * If there's no mount we need to check the usage @@ -208,10 +237,7 @@ static int autofs4_tree_busy(struct vfsmount *mnt, return 1; } } - dput(p); - spin_lock(&dcache_lock); } - spin_unlock(&dcache_lock); /* Timeout of a tree mount is ultimately determined by its top dentry */ if (!autofs4_can_expire(top, timeout, do_now)) @@ -230,36 +256,21 @@ static struct dentry *autofs4_check_leaves(struct vfsmount *mnt, DPRINTK("parent %p %.*s", parent, (int)parent->d_name.len, parent->d_name.name); - spin_lock(&dcache_lock); - for (p = parent; p; p = next_dentry(p, parent)) { - spin_lock(&p->d_lock); - /* Negative dentry - give up */ - if (!simple_positive(p)) { - spin_unlock(&p->d_lock); - continue; - } - + p = NULL; + while ((p = get_next_positive_dentry(p, parent))) { DPRINTK("dentry %p %.*s", p, (int) p->d_name.len, p->d_name.name); - p = dget_dlock(p); - spin_unlock(&p->d_lock); - spin_unlock(&dcache_lock); - if (d_mountpoint(p)) { /* Can we umount this guy */ if (autofs4_mount_busy(mnt, p)) - goto cont; + continue; /* Can we expire this guy */ if (autofs4_can_expire(p, timeout, do_now)) return p; } -cont: - dput(p); - spin_lock(&dcache_lock); } - spin_unlock(&dcache_lock); return NULL; } @@ -310,8 +321,8 @@ struct dentry *autofs4_expire_indirect(struct super_block *sb, { unsigned long timeout; struct dentry *root = sb->s_root; + struct dentry *dentry; struct dentry *expired = NULL; - struct list_head *next; int do_now = how & AUTOFS_EXP_IMMEDIATE; int exp_leaves = how & AUTOFS_EXP_LEAVES; struct autofs_info *ino; @@ -323,26 +334,8 @@ struct dentry *autofs4_expire_indirect(struct super_block *sb, now = jiffies; timeout = sbi->exp_timeout; - spin_lock(&dcache_lock); - next = root->d_subdirs.next; - - /* On exit from the loop expire is set to a dgot dentry - * to expire or it's NULL */ - while ( next != &root->d_subdirs ) { - struct dentry *dentry = list_entry(next, struct dentry, d_u.d_child); - - /* Negative dentry - give up */ - spin_lock(&dentry->d_lock); - if (!simple_positive(dentry)) { - next = next->next; - spin_unlock(&dentry->d_lock); - continue; - } - - dentry = dget_dlock(dentry); - spin_unlock(&dentry->d_lock); - spin_unlock(&dcache_lock); - + dentry = NULL; + while ((dentry = get_next_positive_dentry(dentry, root))) { spin_lock(&sbi->fs_lock); ino = autofs4_dentry_ino(dentry); @@ -405,11 +398,7 @@ struct dentry *autofs4_expire_indirect(struct super_block *sb, } next: spin_unlock(&sbi->fs_lock); - dput(dentry); - spin_lock(&dcache_lock); - next = next->next; } - spin_unlock(&dcache_lock); return NULL; found: @@ -420,7 +409,11 @@ found: init_completion(&ino->expire_complete); spin_unlock(&sbi->fs_lock); spin_lock(&dcache_lock); + spin_lock(&expired->d_parent->d_lock); + spin_lock_nested(&expired->d_lock, DENTRY_D_LOCK_NESTED); list_move(&expired->d_parent->d_subdirs, &expired->d_u.d_child); + spin_unlock(&expired->d_lock); + spin_unlock(&expired->d_parent->d_lock); spin_unlock(&dcache_lock); return expired; } diff --git a/fs/autofs4/root.c b/fs/autofs4/root.c index 7922509b5b2b..7a9ed6b88291 100644 --- a/fs/autofs4/root.c +++ b/fs/autofs4/root.c @@ -143,10 +143,13 @@ static int autofs4_dir_open(struct inode *inode, struct file *file) * it. */ spin_lock(&dcache_lock); + spin_lock(&dentry->d_lock); if (!d_mountpoint(dentry) && list_empty(&dentry->d_subdirs)) { + spin_unlock(&dentry->d_lock); spin_unlock(&dcache_lock); return -ENOENT; } + spin_unlock(&dentry->d_lock); spin_unlock(&dcache_lock); out: @@ -253,7 +256,9 @@ static void *autofs4_follow_link(struct dentry *dentry, struct nameidata *nd) lookup_type = autofs4_need_mount(nd->flags); spin_lock(&sbi->fs_lock); spin_lock(&dcache_lock); + spin_lock(&dentry->d_lock); if (!(lookup_type || ino->flags & AUTOFS_INF_PENDING)) { + spin_unlock(&dentry->d_lock); spin_unlock(&dcache_lock); spin_unlock(&sbi->fs_lock); goto follow; @@ -266,6 +271,7 @@ static void *autofs4_follow_link(struct dentry *dentry, struct nameidata *nd) */ if (ino->flags & AUTOFS_INF_PENDING || (!d_mountpoint(dentry) && list_empty(&dentry->d_subdirs))) { + spin_unlock(&dentry->d_lock); spin_unlock(&dcache_lock); spin_unlock(&sbi->fs_lock); @@ -275,6 +281,7 @@ static void *autofs4_follow_link(struct dentry *dentry, struct nameidata *nd) goto follow; } + spin_unlock(&dentry->d_lock); spin_unlock(&dcache_lock); spin_unlock(&sbi->fs_lock); follow: @@ -347,10 +354,12 @@ static int autofs4_revalidate(struct dentry *dentry, struct nameidata *nd) /* Check for a non-mountpoint directory with no contents */ spin_lock(&dcache_lock); + spin_lock(&dentry->d_lock); if (S_ISDIR(dentry->d_inode->i_mode) && !d_mountpoint(dentry) && list_empty(&dentry->d_subdirs)) { DPRINTK("dentry=%p %.*s, emptydir", dentry, dentry->d_name.len, dentry->d_name.name); + spin_unlock(&dentry->d_lock); spin_unlock(&dcache_lock); /* The daemon never causes a mount to trigger */ @@ -367,6 +376,7 @@ static int autofs4_revalidate(struct dentry *dentry, struct nameidata *nd) return status; } + spin_unlock(&dentry->d_lock); spin_unlock(&dcache_lock); return 1; @@ -776,12 +786,16 @@ static int autofs4_dir_rmdir(struct inode *dir, struct dentry *dentry) return -EACCES; spin_lock(&dcache_lock); + spin_lock(&sbi->lookup_lock); + spin_lock(&dentry->d_lock); if (!list_empty(&dentry->d_subdirs)) { + spin_unlock(&dentry->d_lock); + spin_unlock(&sbi->lookup_lock); spin_unlock(&dcache_lock); return -ENOTEMPTY; } - autofs4_add_expiring(dentry); - spin_lock(&dentry->d_lock); + __autofs4_add_expiring(dentry); + spin_unlock(&sbi->lookup_lock); __d_drop(dentry); spin_unlock(&dentry->d_lock); spin_unlock(&dcache_lock); diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c index 571f270dca0f..2c924e8d85fe 100644 --- a/fs/ceph/dir.c +++ b/fs/ceph/dir.c @@ -113,6 +113,7 @@ static int __dcache_readdir(struct file *filp, last); spin_lock(&dcache_lock); + spin_lock(&parent->d_lock); /* start at beginning? */ if (filp->f_pos == 2 || last == NULL || @@ -136,7 +137,7 @@ more: fi->at_end = 1; goto out_unlock; } - spin_lock(&dentry->d_lock); + spin_lock_nested(&dentry->d_lock, DENTRY_D_LOCK_NESTED); if (!d_unhashed(dentry) && dentry->d_inode && ceph_snap(dentry->d_inode) != CEPH_SNAPDIR && ceph_ino(dentry->d_inode) != CEPH_INO_CEPH && @@ -154,6 +155,7 @@ more: dget_dlock(dentry); spin_unlock(&dentry->d_lock); + spin_unlock(&parent->d_lock); spin_unlock(&dcache_lock); dout(" %llu (%llu) dentry %p %.*s %p\n", di->offset, filp->f_pos, @@ -188,10 +190,12 @@ more: } spin_lock(&dcache_lock); + spin_lock(&parent->d_lock); p = p->prev; /* advance to next dentry */ goto more; out_unlock: + spin_unlock(&parent->d_lock); spin_unlock(&dcache_lock); out: if (last) diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c index bb68c799074d..2c6944473366 100644 --- a/fs/ceph/inode.c +++ b/fs/ceph/inode.c @@ -842,11 +842,13 @@ static void ceph_set_dentry_offset(struct dentry *dn) spin_unlock(&inode->i_lock); spin_lock(&dcache_lock); - spin_lock(&dn->d_lock); + spin_lock(&dir->d_lock); + spin_lock_nested(&dn->d_lock, DENTRY_D_LOCK_NESTED); list_move(&dn->d_u.d_child, &dir->d_subdirs); dout("set_dentry_offset %p %lld (%p %p)\n", dn, di->offset, dn->d_u.d_child.prev, dn->d_u.d_child.next); spin_unlock(&dn->d_lock); + spin_unlock(&dir->d_lock); spin_unlock(&dcache_lock); } @@ -1232,9 +1234,11 @@ retry_lookup: } else { /* reorder parent's d_subdirs */ spin_lock(&dcache_lock); - spin_lock(&dn->d_lock); + spin_lock(&parent->d_lock); + spin_lock_nested(&dn->d_lock, DENTRY_D_LOCK_NESTED); list_move(&dn->d_u.d_child, &parent->d_subdirs); spin_unlock(&dn->d_lock); + spin_unlock(&parent->d_lock); spin_unlock(&dcache_lock); } diff --git a/fs/coda/cache.c b/fs/coda/cache.c index 9060f08e70cf..859393fca2b7 100644 --- a/fs/coda/cache.c +++ b/fs/coda/cache.c @@ -94,6 +94,7 @@ static void coda_flag_children(struct dentry *parent, int flag) struct dentry *de; spin_lock(&dcache_lock); + spin_lock(&parent->d_lock); list_for_each(child, &parent->d_subdirs) { de = list_entry(child, struct dentry, d_u.d_child); @@ -102,6 +103,7 @@ static void coda_flag_children(struct dentry *parent, int flag) continue; coda_flag_inode(de->d_inode, flag); } + spin_unlock(&parent->d_lock); spin_unlock(&dcache_lock); return; } diff --git a/fs/dcache.c b/fs/dcache.c index ee127f9ab274..a661247a20d5 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -47,6 +47,8 @@ * - d_lru * - d_count * - d_unhashed() + * - d_parent and d_subdirs + * - childrens' d_child and d_parent * * Ordering: * dcache_lock @@ -223,24 +225,22 @@ static void dentry_lru_move_tail(struct dentry *dentry) * * If this is the root of the dentry tree, return NULL. * - * dcache_lock and d_lock must be held by caller, are dropped by d_kill. + * dcache_lock and d_lock and d_parent->d_lock must be held by caller, and + * are dropped by d_kill. */ -static struct dentry *d_kill(struct dentry *dentry) +static struct dentry *d_kill(struct dentry *dentry, struct dentry *parent) __releases(dentry->d_lock) + __releases(parent->d_lock) __releases(dcache_lock) { - struct dentry *parent; - list_del(&dentry->d_u.d_child); + if (parent) + spin_unlock(&parent->d_lock); dentry_iput(dentry); /* * dentry_iput drops the locks, at which point nobody (except * transient RCU lookups) can reach this dentry. */ - if (IS_ROOT(dentry)) - parent = NULL; - else - parent = dentry->d_parent; d_free(dentry); return parent; } @@ -312,6 +312,7 @@ EXPORT_SYMBOL(d_drop); void dput(struct dentry *dentry) { + struct dentry *parent; if (!dentry) return; @@ -319,6 +320,10 @@ repeat: if (dentry->d_count == 1) might_sleep(); spin_lock(&dentry->d_lock); + if (IS_ROOT(dentry)) + parent = NULL; + else + parent = dentry->d_parent; if (dentry->d_count == 1) { if (!spin_trylock(&dcache_lock)) { /* @@ -330,10 +335,17 @@ repeat: spin_unlock(&dentry->d_lock); goto repeat; } + if (parent && !spin_trylock(&parent->d_lock)) { + spin_unlock(&dentry->d_lock); + spin_unlock(&dcache_lock); + goto repeat; + } } dentry->d_count--; if (dentry->d_count) { spin_unlock(&dentry->d_lock); + if (parent) + spin_unlock(&parent->d_lock); spin_unlock(&dcache_lock); return; } @@ -355,6 +367,8 @@ repeat: dentry_lru_add(dentry); spin_unlock(&dentry->d_lock); + if (parent) + spin_unlock(&parent->d_lock); spin_unlock(&dcache_lock); return; @@ -363,7 +377,7 @@ unhash_it: kill_it: /* if dentry was on the d_lru list delete it from there */ dentry_lru_del(dentry); - dentry = d_kill(dentry); + dentry = d_kill(dentry, parent); if (dentry) goto repeat; } @@ -584,12 +598,13 @@ EXPORT_SYMBOL(d_prune_aliases); * quadratic behavior of shrink_dcache_parent(), but is also expected * to be beneficial in reducing dentry cache fragmentation. */ -static void prune_one_dentry(struct dentry * dentry) +static void prune_one_dentry(struct dentry *dentry, struct dentry *parent) __releases(dentry->d_lock) + __releases(parent->d_lock) __releases(dcache_lock) { __d_drop(dentry); - dentry = d_kill(dentry); + dentry = d_kill(dentry, parent); /* * Prune ancestors. Locking is simpler than in dput(), @@ -597,9 +612,20 @@ static void prune_one_dentry(struct dentry * dentry) */ while (dentry) { spin_lock(&dcache_lock); +again: spin_lock(&dentry->d_lock); + if (IS_ROOT(dentry)) + parent = NULL; + else + parent = dentry->d_parent; + if (parent && !spin_trylock(&parent->d_lock)) { + spin_unlock(&dentry->d_lock); + goto again; + } dentry->d_count--; if (dentry->d_count) { + if (parent) + spin_unlock(&parent->d_lock); spin_unlock(&dentry->d_lock); spin_unlock(&dcache_lock); return; @@ -607,7 +633,7 @@ static void prune_one_dentry(struct dentry * dentry) dentry_lru_del(dentry); __d_drop(dentry); - dentry = d_kill(dentry); + dentry = d_kill(dentry, parent); } } @@ -616,29 +642,40 @@ static void shrink_dentry_list(struct list_head *list) struct dentry *dentry; while (!list_empty(list)) { + struct dentry *parent; + dentry = list_entry(list->prev, struct dentry, d_lru); if (!spin_trylock(&dentry->d_lock)) { +relock: spin_unlock(&dcache_lru_lock); cpu_relax(); spin_lock(&dcache_lru_lock); continue; } - __dentry_lru_del(dentry); - /* * We found an inuse dentry which was not removed from * the LRU because of laziness during lookup. Do not free * it - just keep it off the LRU list. */ if (dentry->d_count) { + __dentry_lru_del(dentry); spin_unlock(&dentry->d_lock); continue; } + if (IS_ROOT(dentry)) + parent = NULL; + else + parent = dentry->d_parent; + if (parent && !spin_trylock(&parent->d_lock)) { + spin_unlock(&dentry->d_lock); + goto relock; + } + __dentry_lru_del(dentry); spin_unlock(&dcache_lru_lock); - prune_one_dentry(dentry); + prune_one_dentry(dentry, parent); /* dcache_lock and dentry->d_lock dropped */ spin_lock(&dcache_lock); spin_lock(&dcache_lru_lock); @@ -833,14 +870,16 @@ static void shrink_dcache_for_umount_subtree(struct dentry *dentry) /* this is a branch with children - detach all of them * from the system in one go */ spin_lock(&dcache_lock); + spin_lock(&dentry->d_lock); list_for_each_entry(loop, &dentry->d_subdirs, d_u.d_child) { - spin_lock(&loop->d_lock); + spin_lock_nested(&loop->d_lock, + DENTRY_D_LOCK_NESTED); dentry_lru_del(loop); __d_drop(loop); spin_unlock(&loop->d_lock); - cond_resched_lock(&dcache_lock); } + spin_unlock(&dentry->d_lock); spin_unlock(&dcache_lock); /* move to the first child */ @@ -868,16 +907,17 @@ static void shrink_dcache_for_umount_subtree(struct dentry *dentry) BUG(); } - if (IS_ROOT(dentry)) + if (IS_ROOT(dentry)) { parent = NULL; - else { + list_del(&dentry->d_u.d_child); + } else { parent = dentry->d_parent; spin_lock(&parent->d_lock); parent->d_count--; + list_del(&dentry->d_u.d_child); spin_unlock(&parent->d_lock); } - list_del(&dentry->d_u.d_child); detached++; inode = dentry->d_inode; @@ -958,6 +998,7 @@ int have_submounts(struct dentry *parent) spin_lock(&dcache_lock); if (d_mountpoint(parent)) goto positive; + spin_lock(&this_parent->d_lock); repeat: next = this_parent->d_subdirs.next; resume: @@ -965,22 +1006,34 @@ resume: struct list_head *tmp = next; struct dentry *dentry = list_entry(tmp, struct dentry, d_u.d_child); next = tmp->next; + + spin_lock_nested(&dentry->d_lock, DENTRY_D_LOCK_NESTED); /* Have we found a mount point ? */ - if (d_mountpoint(dentry)) + if (d_mountpoint(dentry)) { + spin_unlock(&dentry->d_lock); + spin_unlock(&this_parent->d_lock); goto positive; + } if (!list_empty(&dentry->d_subdirs)) { + spin_unlock(&this_parent->d_lock); + spin_release(&dentry->d_lock.dep_map, 1, _RET_IP_); this_parent = dentry; + spin_acquire(&this_parent->d_lock.dep_map, 0, 1, _RET_IP_); goto repeat; } + spin_unlock(&dentry->d_lock); } /* * All done at this level ... ascend and resume the search. */ if (this_parent != parent) { next = this_parent->d_u.d_child.next; + spin_unlock(&this_parent->d_lock); this_parent = this_parent->d_parent; + spin_lock(&this_parent->d_lock); goto resume; } + spin_unlock(&this_parent->d_lock); spin_unlock(&dcache_lock); return 0; /* No mount points found in tree */ positive: @@ -1010,6 +1063,7 @@ static int select_parent(struct dentry * parent) int found = 0; spin_lock(&dcache_lock); + spin_lock(&this_parent->d_lock); repeat: next = this_parent->d_subdirs.next; resume: @@ -1017,8 +1071,9 @@ resume: struct list_head *tmp = next; struct dentry *dentry = list_entry(tmp, struct dentry, d_u.d_child); next = tmp->next; + BUG_ON(this_parent == dentry); - spin_lock(&dentry->d_lock); + spin_lock_nested(&dentry->d_lock, DENTRY_D_LOCK_NESTED); /* * move only zero ref count dentries to the end @@ -1031,33 +1086,44 @@ resume: dentry_lru_del(dentry); } - spin_unlock(&dentry->d_lock); - /* * 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()) + if (found && need_resched()) { + spin_unlock(&dentry->d_lock); goto out; + } /* * Descend a level if the d_subdirs list is non-empty. */ if (!list_empty(&dentry->d_subdirs)) { + spin_unlock(&this_parent->d_lock); + spin_release(&dentry->d_lock.dep_map, 1, _RET_IP_); this_parent = dentry; + spin_acquire(&this_parent->d_lock.dep_map, 0, 1, _RET_IP_); goto repeat; } + + spin_unlock(&dentry->d_lock); } /* * All done at this level ... ascend and resume the search. */ if (this_parent != parent) { + struct dentry *tmp; next = this_parent->d_u.d_child.next; - this_parent = this_parent->d_parent; + tmp = this_parent->d_parent; + spin_unlock(&this_parent->d_lock); + BUG_ON(tmp == this_parent); + this_parent = tmp; + spin_lock(&this_parent->d_lock); goto resume; } out: + spin_unlock(&this_parent->d_lock); spin_unlock(&dcache_lock); return found; } @@ -1155,18 +1221,19 @@ struct dentry *d_alloc(struct dentry * parent, const struct qstr *name) INIT_LIST_HEAD(&dentry->d_lru); INIT_LIST_HEAD(&dentry->d_subdirs); INIT_LIST_HEAD(&dentry->d_alias); + INIT_LIST_HEAD(&dentry->d_u.d_child); if (parent) { - dentry->d_parent = dget(parent); + spin_lock(&dcache_lock); + spin_lock(&parent->d_lock); + spin_lock_nested(&dentry->d_lock, DENTRY_D_LOCK_NESTED); + dentry->d_parent = dget_dlock(parent); dentry->d_sb = parent->d_sb; - } else { - INIT_LIST_HEAD(&dentry->d_u.d_child); - } - - spin_lock(&dcache_lock); - if (parent) list_add(&dentry->d_u.d_child, &parent->d_subdirs); - spin_unlock(&dcache_lock); + spin_unlock(&dentry->d_lock); + spin_unlock(&parent->d_lock); + spin_unlock(&dcache_lock); + } this_cpu_inc(nr_dentry); @@ -1684,13 +1751,18 @@ int d_validate(struct dentry *dentry, struct dentry *dparent) struct dentry *child; spin_lock(&dcache_lock); + spin_lock(&dparent->d_lock); list_for_each_entry(child, &dparent->d_subdirs, d_u.d_child) { if (dentry == child) { - __dget_locked(dentry); + spin_lock_nested(&dentry->d_lock, DENTRY_D_LOCK_NESTED); + __dget_locked_dlock(dentry); + spin_unlock(&dentry->d_lock); + spin_unlock(&dparent->d_lock); spin_unlock(&dcache_lock); return 1; } } + spin_unlock(&dparent->d_lock); spin_unlock(&dcache_lock); return 0; @@ -1802,17 +1874,6 @@ void dentry_update_name_case(struct dentry *dentry, struct qstr *name) } EXPORT_SYMBOL(dentry_update_name_case); -/* - * 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)) { @@ -1854,18 +1915,53 @@ static void switch_names(struct dentry *dentry, struct dentry *target) swap(dentry->d_name.len, target->d_name.len); } +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); +} + /* - * 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 - * 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. + * 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.. */ - /* * d_move_locked - move a dentry * @dentry: entry to move @@ -1879,20 +1975,12 @@ static void d_move_locked(struct dentry * dentry, struct dentry * target) if (!dentry->d_inode) printk(KERN_WARNING "VFS: moving negative dcache entry\n"); + BUG_ON(d_ancestor(dentry, target)); + BUG_ON(d_ancestor(target, dentry)); + write_seqlock(&rename_lock); - /* - * XXXX: do we really need to take target->d_lock? - */ - if (d_ancestor(dentry, target)) { - spin_lock(&dentry->d_lock); - spin_lock_nested(&target->d_lock, DENTRY_D_LOCK_NESTED); - } else if (d_ancestor(target, dentry) || target < dentry) { - spin_lock(&target->d_lock); - spin_lock_nested(&dentry->d_lock, DENTRY_D_LOCK_NESTED); - } else { - spin_lock(&dentry->d_lock); - spin_lock_nested(&target->d_lock, DENTRY_D_LOCK_NESTED); - } + + dentry_lock_for_move(dentry, target); /* Move the dentry to the target hash queue, if on different bucket */ spin_lock(&dcache_hash_lock); @@ -1924,6 +2012,8 @@ static void d_move_locked(struct dentry * dentry, struct dentry * target) } list_add(&dentry->d_u.d_child, &dentry->d_parent->d_subdirs); + + dentry_unlock_parents_for_move(dentry, target); spin_unlock(&target->d_lock); fsnotify_d_move(dentry); spin_unlock(&dentry->d_lock); @@ -2013,17 +2103,20 @@ out_err: /* * Prepare an anonymous dentry for life in the superblock's dentry tree as a * named dentry in place of the dentry to be replaced. + * returns with anon->d_lock held! */ static void __d_materialise_dentry(struct dentry *dentry, struct dentry *anon) { struct dentry *dparent, *aparent; - switch_names(dentry, anon); - swap(dentry->d_name.hash, anon->d_name.hash); + dentry_lock_for_move(anon, dentry); dparent = dentry->d_parent; aparent = anon->d_parent; + switch_names(dentry, anon); + swap(dentry->d_name.hash, anon->d_name.hash); + dentry->d_parent = (aparent == anon) ? dentry : aparent; list_del(&dentry->d_u.d_child); if (!IS_ROOT(dentry)) @@ -2038,6 +2131,10 @@ static void __d_materialise_dentry(struct dentry *dentry, struct dentry *anon) else INIT_LIST_HEAD(&anon->d_u.d_child); + dentry_unlock_parents_for_move(anon, dentry); + spin_unlock(&dentry->d_lock); + + /* anon->d_lock still locked, returns locked */ anon->d_flags &= ~DCACHE_DISCONNECTED; } @@ -2073,7 +2170,6 @@ struct dentry *d_materialise_unique(struct dentry *dentry, struct inode *inode) /* 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; @@ -2558,6 +2654,7 @@ void d_genocide(struct dentry *root) struct list_head *next; spin_lock(&dcache_lock); + spin_lock(&this_parent->d_lock); repeat: next = this_parent->d_subdirs.next; resume: @@ -2571,8 +2668,10 @@ resume: continue; } if (!list_empty(&dentry->d_subdirs)) { - spin_unlock(&dentry->d_lock); + spin_unlock(&this_parent->d_lock); + spin_release(&dentry->d_lock.dep_map, 1, _RET_IP_); this_parent = dentry; + spin_acquire(&this_parent->d_lock.dep_map, 0, 1, _RET_IP_); goto repeat; } dentry->d_count--; @@ -2580,12 +2679,13 @@ resume: } if (this_parent != root) { next = this_parent->d_u.d_child.next; - spin_lock(&this_parent->d_lock); this_parent->d_count--; spin_unlock(&this_parent->d_lock); this_parent = this_parent->d_parent; + spin_lock(&this_parent->d_lock); goto resume; } + spin_unlock(&this_parent->d_lock); spin_unlock(&dcache_lock); } diff --git a/fs/libfs.c b/fs/libfs.c index 433e7139c23a..cc4794914b52 100644 --- a/fs/libfs.c +++ b/fs/libfs.c @@ -81,7 +81,8 @@ int dcache_dir_close(struct inode *inode, struct file *file) loff_t dcache_dir_lseek(struct file *file, loff_t offset, int origin) { - mutex_lock(&file->f_path.dentry->d_inode->i_mutex); + struct dentry *dentry = file->f_path.dentry; + mutex_lock(&dentry->d_inode->i_mutex); switch (origin) { case 1: offset += file->f_pos; @@ -89,7 +90,7 @@ loff_t dcache_dir_lseek(struct file *file, loff_t offset, int origin) if (offset >= 0) break; default: - mutex_unlock(&file->f_path.dentry->d_inode->i_mutex); + mutex_unlock(&dentry->d_inode->i_mutex); return -EINVAL; } if (offset != file->f_pos) { @@ -100,22 +101,25 @@ loff_t dcache_dir_lseek(struct file *file, loff_t offset, int origin) loff_t n = file->f_pos - 2; spin_lock(&dcache_lock); + spin_lock(&dentry->d_lock); + /* d_lock not required for cursor */ list_del(&cursor->d_u.d_child); - p = file->f_path.dentry->d_subdirs.next; - while (n && p != &file->f_path.dentry->d_subdirs) { + p = dentry->d_subdirs.next; + while (n && p != &dentry->d_subdirs) { struct dentry *next; next = list_entry(p, struct dentry, d_u.d_child); - spin_lock(&next->d_lock); + spin_lock_nested(&next->d_lock, DENTRY_D_LOCK_NESTED); if (simple_positive(next)) n--; spin_unlock(&next->d_lock); p = p->next; } list_add_tail(&cursor->d_u.d_child, p); + spin_unlock(&dentry->d_lock); spin_unlock(&dcache_lock); } } - mutex_unlock(&file->f_path.dentry->d_inode->i_mutex); + mutex_unlock(&dentry->d_inode->i_mutex); return offset; } @@ -156,6 +160,7 @@ int dcache_readdir(struct file * filp, void * dirent, filldir_t filldir) /* fallthrough */ default: spin_lock(&dcache_lock); + spin_lock(&dentry->d_lock); if (filp->f_pos == 2) list_move(q, &dentry->d_subdirs); @@ -169,6 +174,7 @@ int dcache_readdir(struct file * filp, void * dirent, filldir_t filldir) } spin_unlock(&next->d_lock); + spin_unlock(&dentry->d_lock); spin_unlock(&dcache_lock); if (filldir(dirent, next->d_name.name, next->d_name.len, filp->f_pos, @@ -176,11 +182,15 @@ int dcache_readdir(struct file * filp, void * dirent, filldir_t filldir) dt_type(next->d_inode)) < 0) return 0; spin_lock(&dcache_lock); + spin_lock(&dentry->d_lock); + spin_lock_nested(&next->d_lock, DENTRY_D_LOCK_NESTED); /* next is still alive */ list_move(q, p); + spin_unlock(&next->d_lock); p = q; filp->f_pos++; } + spin_unlock(&dentry->d_lock); spin_unlock(&dcache_lock); } return 0; @@ -276,6 +286,7 @@ int simple_empty(struct dentry *dentry) int ret = 0; spin_lock(&dcache_lock); + spin_lock(&dentry->d_lock); list_for_each_entry(child, &dentry->d_subdirs, d_u.d_child) { spin_lock_nested(&child->d_lock, DENTRY_D_LOCK_NESTED); if (simple_positive(child)) { @@ -286,6 +297,7 @@ int simple_empty(struct dentry *dentry) } ret = 1; out: + spin_unlock(&dentry->d_lock); spin_unlock(&dcache_lock); return ret; } diff --git a/fs/ncpfs/dir.c b/fs/ncpfs/dir.c index bbbf7922f422..102278ed38bd 100644 --- a/fs/ncpfs/dir.c +++ b/fs/ncpfs/dir.c @@ -392,6 +392,7 @@ ncp_dget_fpos(struct dentry *dentry, struct dentry *parent, unsigned long fpos) /* If a pointer is invalid, we search the dentry. */ spin_lock(&dcache_lock); + spin_lock(&parent->d_lock); next = parent->d_subdirs.next; while (next != &parent->d_subdirs) { dent = list_entry(next, struct dentry, d_u.d_child); @@ -400,11 +401,13 @@ ncp_dget_fpos(struct dentry *dentry, struct dentry *parent, unsigned long fpos) dget_locked(dent); else dent = NULL; + spin_unlock(&parent->d_lock); spin_unlock(&dcache_lock); goto out; } next = next->next; } + spin_unlock(&parent->d_lock); spin_unlock(&dcache_lock); return NULL; diff --git a/fs/ncpfs/ncplib_kernel.h b/fs/ncpfs/ncplib_kernel.h index 244d1b73fda7..c4b718ff9a6b 100644 --- a/fs/ncpfs/ncplib_kernel.h +++ b/fs/ncpfs/ncplib_kernel.h @@ -194,6 +194,7 @@ ncp_renew_dentries(struct dentry *parent) struct dentry *dentry; spin_lock(&dcache_lock); + spin_lock(&parent->d_lock); next = parent->d_subdirs.next; while (next != &parent->d_subdirs) { dentry = list_entry(next, struct dentry, d_u.d_child); @@ -205,6 +206,7 @@ ncp_renew_dentries(struct dentry *parent) next = next->next; } + spin_unlock(&parent->d_lock); spin_unlock(&dcache_lock); } @@ -216,6 +218,7 @@ ncp_invalidate_dircache_entries(struct dentry *parent) struct dentry *dentry; spin_lock(&dcache_lock); + spin_lock(&parent->d_lock); next = parent->d_subdirs.next; while (next != &parent->d_subdirs) { dentry = list_entry(next, struct dentry, d_u.d_child); @@ -223,6 +226,7 @@ ncp_invalidate_dircache_entries(struct dentry *parent) ncp_age_dentry(server, dentry); next = next->next; } + spin_unlock(&parent->d_lock); spin_unlock(&dcache_lock); } diff --git a/fs/notify/fsnotify.c b/fs/notify/fsnotify.c index 20dc218707ca..aa4f25e803f6 100644 --- a/fs/notify/fsnotify.c +++ b/fs/notify/fsnotify.c @@ -68,17 +68,19 @@ void __fsnotify_update_child_dentry_flags(struct inode *inode) /* run all of the children of the original inode and fix their * d_flags to indicate parental interest (their parent is the * original inode) */ + spin_lock(&alias->d_lock); list_for_each_entry(child, &alias->d_subdirs, d_u.d_child) { if (!child->d_inode) continue; - spin_lock(&child->d_lock); + spin_lock_nested(&child->d_lock, DENTRY_D_LOCK_NESTED); if (watched) child->d_flags |= DCACHE_FSNOTIFY_PARENT_WATCHED; else child->d_flags &= ~DCACHE_FSNOTIFY_PARENT_WATCHED; spin_unlock(&child->d_lock); } + spin_unlock(&alias->d_lock); } spin_unlock(&dcache_lock); } diff --git a/include/linux/dcache.h b/include/linux/dcache.h index b0ade2d46805..ddf4f55624f7 100644 --- a/include/linux/dcache.h +++ b/include/linux/dcache.h @@ -305,6 +305,7 @@ static inline struct dentry *dget_dlock(struct dentry *dentry) } return dentry; } + static inline struct dentry *dget(struct dentry *dentry) { if (dentry) { diff --git a/kernel/cgroup.c b/kernel/cgroup.c index eb7af39350c6..7b4705b51d4a 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -877,23 +877,31 @@ static void cgroup_clear_directory(struct dentry *dentry) BUG_ON(!mutex_is_locked(&dentry->d_inode->i_mutex)); spin_lock(&dcache_lock); + spin_lock(&dentry->d_lock); node = dentry->d_subdirs.next; while (node != &dentry->d_subdirs) { struct dentry *d = list_entry(node, struct dentry, d_u.d_child); + + spin_lock_nested(&d->d_lock, DENTRY_D_LOCK_NESTED); list_del_init(node); if (d->d_inode) { /* This should never be called on a cgroup * directory with child cgroups */ BUG_ON(d->d_inode->i_mode & S_IFDIR); - d = dget_locked(d); + dget_locked_dlock(d); + spin_unlock(&d->d_lock); + spin_unlock(&dentry->d_lock); spin_unlock(&dcache_lock); d_delete(d); simple_unlink(dentry->d_inode, d); dput(d); spin_lock(&dcache_lock); - } + spin_lock(&dentry->d_lock); + } else + spin_unlock(&d->d_lock); node = dentry->d_subdirs.next; } + spin_unlock(&dentry->d_lock); spin_unlock(&dcache_lock); } @@ -902,10 +910,17 @@ static void cgroup_clear_directory(struct dentry *dentry) */ static void cgroup_d_remove_dir(struct dentry *dentry) { + struct dentry *parent; + cgroup_clear_directory(dentry); spin_lock(&dcache_lock); + parent = dentry->d_parent; + spin_lock(&parent->d_lock); + spin_lock(&dentry->d_lock); list_del_init(&dentry->d_u.d_child); + spin_unlock(&dentry->d_lock); + spin_unlock(&parent->d_lock); spin_unlock(&dcache_lock); remove_dir(dentry); } diff --git a/security/selinux/selinuxfs.c b/security/selinux/selinuxfs.c index 073fd5b0a53a..017ec096446e 100644 --- a/security/selinux/selinuxfs.c +++ b/security/selinux/selinuxfs.c @@ -1146,22 +1146,30 @@ static void sel_remove_entries(struct dentry *de) struct list_head *node; spin_lock(&dcache_lock); + spin_lock(&de->d_lock); node = de->d_subdirs.next; while (node != &de->d_subdirs) { struct dentry *d = list_entry(node, struct dentry, d_u.d_child); + + spin_lock_nested(&d->d_lock, DENTRY_D_LOCK_NESTED); list_del_init(node); if (d->d_inode) { - d = dget_locked(d); + dget_locked_dlock(d); + spin_unlock(&de->d_lock); + spin_unlock(&d->d_lock); spin_unlock(&dcache_lock); d_delete(d); simple_unlink(de->d_inode, d); dput(d); spin_lock(&dcache_lock); - } + spin_lock(&de->d_lock); + } else + spin_unlock(&d->d_lock); node = de->d_subdirs.next; } + spin_unlock(&de->d_lock); spin_unlock(&dcache_lock); } -- cgit v1.2.3 From b5c84bf6f6fa3a7dfdcb556023a62953574b60ee Mon Sep 17 00:00:00 2001 From: Nick Piggin Date: Fri, 7 Jan 2011 17:49:38 +1100 Subject: fs: dcache remove dcache_lock dcache_lock no longer protects anything. remove it. Signed-off-by: Nick Piggin --- Documentation/filesystems/Locking | 16 +-- Documentation/filesystems/dentry-locking.txt | 40 ++++--- Documentation/filesystems/porting | 8 +- arch/powerpc/platforms/cell/spufs/inode.c | 5 +- drivers/infiniband/hw/ipath/ipath_fs.c | 6 +- drivers/infiniband/hw/qib/qib_fs.c | 3 - drivers/staging/pohmelfs/path_entry.c | 2 - drivers/staging/smbfs/cache.c | 4 - drivers/usb/core/inode.c | 3 - fs/9p/vfs_inode.c | 2 - fs/affs/amigaffs.c | 2 - fs/autofs4/autofs_i.h | 3 + fs/autofs4/expire.c | 10 +- fs/autofs4/root.c | 44 ++++---- fs/autofs4/waitq.c | 7 +- fs/ceph/dir.c | 6 +- fs/ceph/inode.c | 4 - fs/cifs/inode.c | 3 - fs/coda/cache.c | 2 - fs/configfs/configfs_internal.h | 2 - fs/configfs/inode.c | 6 +- fs/dcache.c | 160 ++++----------------------- fs/exportfs/expfs.c | 4 - fs/libfs.c | 8 -- fs/namei.c | 9 +- fs/ncpfs/dir.c | 3 - fs/ncpfs/ncplib_kernel.h | 4 - fs/nfs/dir.c | 3 - fs/nfs/getroot.c | 2 - fs/nfs/namespace.c | 3 - fs/notify/fsnotify.c | 2 - fs/ocfs2/dcache.c | 2 - include/linux/dcache.h | 5 +- include/linux/fs.h | 6 +- include/linux/fsnotify.h | 2 - include/linux/fsnotify_backend.h | 11 +- include/linux/namei.h | 1 - kernel/cgroup.c | 6 - mm/filemap.c | 3 - security/selinux/selinuxfs.c | 4 - 40 files changed, 109 insertions(+), 307 deletions(-) (limited to 'drivers/usb') diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking index a15ee207b449..bdad6414dfa0 100644 --- a/Documentation/filesystems/Locking +++ b/Documentation/filesystems/Locking @@ -21,14 +21,14 @@ prototypes: char *(*d_dname)((struct dentry *dentry, char *buffer, int buflen); locking rules: - dcache_lock rename_lock ->d_lock may block -d_revalidate: no no no yes -d_hash no no no no -d_compare: no yes no no -d_delete: yes no yes no -d_release: no no no yes -d_iput: no no no yes -d_dname: no no no no + rename_lock ->d_lock may block +d_revalidate: no no yes +d_hash no no no +d_compare: yes no no +d_delete: no yes no +d_release: no no yes +d_iput: no no yes +d_dname: no no no --------------------------- inode_operations --------------------------- prototypes: diff --git a/Documentation/filesystems/dentry-locking.txt b/Documentation/filesystems/dentry-locking.txt index 79334ed5daa7..30b6a40f5650 100644 --- a/Documentation/filesystems/dentry-locking.txt +++ b/Documentation/filesystems/dentry-locking.txt @@ -31,6 +31,7 @@ significant change is the way d_lookup traverses the hash chain, it doesn't acquire the dcache_lock for this and rely on RCU to ensure that the dentry has not been *freed*. +dcache_lock no longer exists, dentry locking is explained in fs/dcache.c Dcache locking details ====================== @@ -50,14 +51,12 @@ Safe lock-free look-up of dcache hash table Dcache is a complex data structure with the hash table entries also linked together in other lists. In 2.4 kernel, dcache_lock protected -all the lists. We applied RCU only on hash chain walking. The rest of -the lists are still protected by dcache_lock. Some of the important -changes are : +all the lists. RCU dentry hash walking works like this: 1. The deletion from hash chain is done using hlist_del_rcu() macro which doesn't initialize next pointer of the deleted dentry and this allows us to walk safely lock-free while a deletion is - happening. + happening. This is a standard hlist_rcu iteration. 2. Insertion of a dentry into the hash table is done using hlist_add_head_rcu() which take care of ordering the writes - the @@ -66,19 +65,18 @@ changes are : which has since been replaced by hlist_for_each_entry_rcu(), while walking the hash chain. The only requirement is that all initialization to the dentry must be done before - hlist_add_head_rcu() since we don't have dcache_lock protection - while traversing the hash chain. This isn't different from the - existing code. - -3. The dentry looked up without holding dcache_lock by cannot be - returned for walking if it is unhashed. It then may have a NULL - d_inode or other bogosity since RCU doesn't protect the other - fields in the dentry. We therefore use a flag DCACHE_UNHASHED to - indicate unhashed dentries and use this in conjunction with a - per-dentry lock (d_lock). Once looked up without the dcache_lock, - we acquire the per-dentry lock (d_lock) and check if the dentry is - unhashed. If so, the look-up is failed. If not, the reference count - of the dentry is increased and the dentry is returned. + hlist_add_head_rcu() since we don't have lock protection + while traversing the hash chain. + +3. The dentry looked up without holding locks cannot be returned for + walking if it is unhashed. It then may have a NULL d_inode or other + bogosity since RCU doesn't protect the other fields in the dentry. We + therefore use a flag DCACHE_UNHASHED to indicate unhashed dentries + and use this in conjunction with a per-dentry lock (d_lock). Once + looked up without locks, we acquire the per-dentry lock (d_lock) and + check if the dentry is unhashed. If so, the look-up is failed. If not, + the reference count of the dentry is increased and the dentry is + returned. 4. Once a dentry is looked up, it must be ensured during the path walk for that component it doesn't go away. In pre-2.5.10 code, this was @@ -86,10 +84,10 @@ changes are : In some sense, dcache_rcu path walking looks like the pre-2.5.10 version. -5. All dentry hash chain updates must take the dcache_lock as well as - the per-dentry lock in that order. dput() does this to ensure that - a dentry that has just been looked up in another CPU doesn't get - deleted before dget() can be done on it. +5. All dentry hash chain updates must take the per-dentry lock (see + fs/dcache.c). This excludes dput() to ensure that a dentry that has + been looked up concurrently does not get deleted before dget() can + take a ref. 6. There are several ways to do reference counting of RCU protected objects. One such example is in ipv4 route cache where deferred diff --git a/Documentation/filesystems/porting b/Documentation/filesystems/porting index 9fd31940a8ef..1eb76959d096 100644 --- a/Documentation/filesystems/porting +++ b/Documentation/filesystems/porting @@ -216,7 +216,6 @@ had ->revalidate()) add calls in ->follow_link()/->readlink(). ->d_parent changes are not protected by BKL anymore. Read access is safe if at least one of the following is true: * filesystem has no cross-directory rename() - * dcache_lock is held * we know that parent had been locked (e.g. we are looking at ->d_parent of ->lookup() argument). * we are called from ->rename(). @@ -340,3 +339,10 @@ look at examples of other filesystems) for guidance. .d_hash() calling convention and locking rules are significantly changed. Read updated documentation in Documentation/filesystems/vfs.txt (and look at examples of other filesystems) for guidance. + +--- +[mandatory] + dcache_lock is gone, replaced by fine grained locks. See fs/dcache.c +for details of what locks to replace dcache_lock with in order to protect +particular things. Most of the time, a filesystem only needs ->d_lock, which +protects *all* the dcache state of a given dentry. diff --git a/arch/powerpc/platforms/cell/spufs/inode.c b/arch/powerpc/platforms/cell/spufs/inode.c index 5aef1a7f5e4b..2662b50ea8d4 100644 --- a/arch/powerpc/platforms/cell/spufs/inode.c +++ b/arch/powerpc/platforms/cell/spufs/inode.c @@ -159,21 +159,18 @@ static void spufs_prune_dir(struct dentry *dir) mutex_lock(&dir->d_inode->i_mutex); list_for_each_entry_safe(dentry, tmp, &dir->d_subdirs, d_u.d_child) { - spin_lock(&dcache_lock); spin_lock(&dentry->d_lock); if (!(d_unhashed(dentry)) && dentry->d_inode) { dget_locked_dlock(dentry); __d_drop(dentry); spin_unlock(&dentry->d_lock); simple_unlink(dir->d_inode, dentry); - /* XXX: what is dcache_lock protecting here? Other + /* XXX: what was dcache_lock protecting here? Other * filesystems (IB, configfs) release dcache_lock * before unlink */ - spin_unlock(&dcache_lock); dput(dentry); } else { spin_unlock(&dentry->d_lock); - spin_unlock(&dcache_lock); } } shrink_dcache_parent(dir); diff --git a/drivers/infiniband/hw/ipath/ipath_fs.c b/drivers/infiniband/hw/ipath/ipath_fs.c index 18aee04a8411..925e88227ded 100644 --- a/drivers/infiniband/hw/ipath/ipath_fs.c +++ b/drivers/infiniband/hw/ipath/ipath_fs.c @@ -277,18 +277,14 @@ static int remove_file(struct dentry *parent, char *name) goto bail; } - spin_lock(&dcache_lock); spin_lock(&tmp->d_lock); if (!(d_unhashed(tmp) && tmp->d_inode)) { dget_locked_dlock(tmp); __d_drop(tmp); spin_unlock(&tmp->d_lock); - spin_unlock(&dcache_lock); simple_unlink(parent->d_inode, tmp); - } else { + } else spin_unlock(&tmp->d_lock); - spin_unlock(&dcache_lock); - } ret = 0; bail: diff --git a/drivers/infiniband/hw/qib/qib_fs.c b/drivers/infiniband/hw/qib/qib_fs.c index fe4b242f0094..49af4a6538ba 100644 --- a/drivers/infiniband/hw/qib/qib_fs.c +++ b/drivers/infiniband/hw/qib/qib_fs.c @@ -453,17 +453,14 @@ static int remove_file(struct dentry *parent, char *name) goto bail; } - spin_lock(&dcache_lock); spin_lock(&tmp->d_lock); if (!(d_unhashed(tmp) && tmp->d_inode)) { dget_locked_dlock(tmp); __d_drop(tmp); spin_unlock(&tmp->d_lock); - spin_unlock(&dcache_lock); simple_unlink(parent->d_inode, tmp); } else { spin_unlock(&tmp->d_lock); - spin_unlock(&dcache_lock); } ret = 0; diff --git a/drivers/staging/pohmelfs/path_entry.c b/drivers/staging/pohmelfs/path_entry.c index bbe42f42ca8f..400a9fc386ad 100644 --- a/drivers/staging/pohmelfs/path_entry.c +++ b/drivers/staging/pohmelfs/path_entry.c @@ -101,7 +101,6 @@ rename_retry: d = first; seq = read_seqbegin(&rename_lock); rcu_read_lock(); - spin_lock(&dcache_lock); if (!IS_ROOT(d) && d_unhashed(d)) len += UNHASHED_OBSCURE_STRING_SIZE; /* Obscure " (deleted)" string */ @@ -110,7 +109,6 @@ rename_retry: len += d->d_name.len + 1; /* Plus slash */ d = d->d_parent; } - spin_unlock(&dcache_lock); rcu_read_unlock(); if (read_seqretry(&rename_lock, seq)) goto rename_retry; diff --git a/drivers/staging/smbfs/cache.c b/drivers/staging/smbfs/cache.c index 920434b6c071..75dfd403fb90 100644 --- a/drivers/staging/smbfs/cache.c +++ b/drivers/staging/smbfs/cache.c @@ -62,7 +62,6 @@ smb_invalidate_dircache_entries(struct dentry *parent) struct list_head *next; struct dentry *dentry; - spin_lock(&dcache_lock); spin_lock(&parent->d_lock); next = parent->d_subdirs.next; while (next != &parent->d_subdirs) { @@ -72,7 +71,6 @@ smb_invalidate_dircache_entries(struct dentry *parent) next = next->next; } spin_unlock(&parent->d_lock); - spin_unlock(&dcache_lock); } /* @@ -98,7 +96,6 @@ smb_dget_fpos(struct dentry *dentry, struct dentry *parent, unsigned long fpos) } /* If a pointer is invalid, we search the dentry. */ - spin_lock(&dcache_lock); spin_lock(&parent->d_lock); next = parent->d_subdirs.next; while (next != &parent->d_subdirs) { @@ -115,7 +112,6 @@ smb_dget_fpos(struct dentry *dentry, struct dentry *parent, unsigned long fpos) dent = NULL; out_unlock: spin_unlock(&parent->d_lock); - spin_unlock(&dcache_lock); return dent; } diff --git a/drivers/usb/core/inode.c b/drivers/usb/core/inode.c index 89a0e8366585..1b125c224dcf 100644 --- a/drivers/usb/core/inode.c +++ b/drivers/usb/core/inode.c @@ -343,7 +343,6 @@ static int usbfs_empty (struct dentry *dentry) { struct list_head *list; - spin_lock(&dcache_lock); spin_lock(&dentry->d_lock); list_for_each(list, &dentry->d_subdirs) { struct dentry *de = list_entry(list, struct dentry, d_u.d_child); @@ -352,13 +351,11 @@ static int usbfs_empty (struct dentry *dentry) if (usbfs_positive(de)) { spin_unlock(&de->d_lock); spin_unlock(&dentry->d_lock); - spin_unlock(&dcache_lock); return 0; } spin_unlock(&de->d_lock); } spin_unlock(&dentry->d_lock); - spin_unlock(&dcache_lock); return 1; } diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c index 47dfd5d29a6b..1073bca8488c 100644 --- a/fs/9p/vfs_inode.c +++ b/fs/9p/vfs_inode.c @@ -270,13 +270,11 @@ static struct dentry *v9fs_dentry_from_dir_inode(struct inode *inode) { struct dentry *dentry; - spin_lock(&dcache_lock); spin_lock(&dcache_inode_lock); /* Directory should have only one entry. */ BUG_ON(S_ISDIR(inode->i_mode) && !list_is_singular(&inode->i_dentry)); dentry = list_entry(inode->i_dentry.next, struct dentry, d_alias); spin_unlock(&dcache_inode_lock); - spin_unlock(&dcache_lock); return dentry; } diff --git a/fs/affs/amigaffs.c b/fs/affs/amigaffs.c index 2321cc92d44f..600101a21ba2 100644 --- a/fs/affs/amigaffs.c +++ b/fs/affs/amigaffs.c @@ -128,7 +128,6 @@ affs_fix_dcache(struct dentry *dentry, u32 entry_ino) void *data = dentry->d_fsdata; struct list_head *head, *next; - spin_lock(&dcache_lock); spin_lock(&dcache_inode_lock); head = &inode->i_dentry; next = head->next; @@ -141,7 +140,6 @@ affs_fix_dcache(struct dentry *dentry, u32 entry_ino) next = next->next; } spin_unlock(&dcache_inode_lock); - spin_unlock(&dcache_lock); } diff --git a/fs/autofs4/autofs_i.h b/fs/autofs4/autofs_i.h index 9d2ae9b30d9f..0fffe1c24cec 100644 --- a/fs/autofs4/autofs_i.h +++ b/fs/autofs4/autofs_i.h @@ -16,6 +16,7 @@ #include #include #include +#include #include /* This is the range of ioctl() numbers we claim as ours */ @@ -60,6 +61,8 @@ do { \ current->pid, __func__, ##args); \ } while (0) +extern spinlock_t autofs4_lock; + /* Unified info structure. This is pointed to by both the dentry and inode structures. Each file in the filesystem has an instance of this structure. It holds a reference to the dentry, so dentries are never diff --git a/fs/autofs4/expire.c b/fs/autofs4/expire.c index 968c1434af62..2f7951d67d16 100644 --- a/fs/autofs4/expire.c +++ b/fs/autofs4/expire.c @@ -102,7 +102,7 @@ static struct dentry *get_next_positive_dentry(struct dentry *prev, if (prev == NULL) return dget(prev); - spin_lock(&dcache_lock); + spin_lock(&autofs4_lock); relock: p = prev; spin_lock(&p->d_lock); @@ -114,7 +114,7 @@ again: if (p == root) { spin_unlock(&p->d_lock); - spin_unlock(&dcache_lock); + spin_unlock(&autofs4_lock); dput(prev); return NULL; } @@ -144,7 +144,7 @@ again: dget_dlock(ret); spin_unlock(&ret->d_lock); spin_unlock(&p->d_lock); - spin_unlock(&dcache_lock); + spin_unlock(&autofs4_lock); dput(prev); @@ -408,13 +408,13 @@ found: ino->flags |= AUTOFS_INF_EXPIRING; init_completion(&ino->expire_complete); spin_unlock(&sbi->fs_lock); - spin_lock(&dcache_lock); + spin_lock(&autofs4_lock); spin_lock(&expired->d_parent->d_lock); spin_lock_nested(&expired->d_lock, DENTRY_D_LOCK_NESTED); list_move(&expired->d_parent->d_subdirs, &expired->d_u.d_child); spin_unlock(&expired->d_lock); spin_unlock(&expired->d_parent->d_lock); - spin_unlock(&dcache_lock); + spin_unlock(&autofs4_lock); return expired; } diff --git a/fs/autofs4/root.c b/fs/autofs4/root.c index 7a9ed6b88291..10ca68a96dc7 100644 --- a/fs/autofs4/root.c +++ b/fs/autofs4/root.c @@ -23,6 +23,8 @@ #include "autofs_i.h" +DEFINE_SPINLOCK(autofs4_lock); + static int autofs4_dir_symlink(struct inode *,struct dentry *,const char *); static int autofs4_dir_unlink(struct inode *,struct dentry *); static int autofs4_dir_rmdir(struct inode *,struct dentry *); @@ -142,15 +144,15 @@ static int autofs4_dir_open(struct inode *inode, struct file *file) * autofs file system so just let the libfs routines handle * it. */ - spin_lock(&dcache_lock); + spin_lock(&autofs4_lock); spin_lock(&dentry->d_lock); if (!d_mountpoint(dentry) && list_empty(&dentry->d_subdirs)) { spin_unlock(&dentry->d_lock); - spin_unlock(&dcache_lock); + spin_unlock(&autofs4_lock); return -ENOENT; } spin_unlock(&dentry->d_lock); - spin_unlock(&dcache_lock); + spin_unlock(&autofs4_lock); out: return dcache_dir_open(inode, file); @@ -255,11 +257,11 @@ static void *autofs4_follow_link(struct dentry *dentry, struct nameidata *nd) /* We trigger a mount for almost all flags */ lookup_type = autofs4_need_mount(nd->flags); spin_lock(&sbi->fs_lock); - spin_lock(&dcache_lock); + spin_lock(&autofs4_lock); spin_lock(&dentry->d_lock); if (!(lookup_type || ino->flags & AUTOFS_INF_PENDING)) { spin_unlock(&dentry->d_lock); - spin_unlock(&dcache_lock); + spin_unlock(&autofs4_lock); spin_unlock(&sbi->fs_lock); goto follow; } @@ -272,7 +274,7 @@ static void *autofs4_follow_link(struct dentry *dentry, struct nameidata *nd) if (ino->flags & AUTOFS_INF_PENDING || (!d_mountpoint(dentry) && list_empty(&dentry->d_subdirs))) { spin_unlock(&dentry->d_lock); - spin_unlock(&dcache_lock); + spin_unlock(&autofs4_lock); spin_unlock(&sbi->fs_lock); status = try_to_fill_dentry(dentry, nd->flags); @@ -282,7 +284,7 @@ static void *autofs4_follow_link(struct dentry *dentry, struct nameidata *nd) goto follow; } spin_unlock(&dentry->d_lock); - spin_unlock(&dcache_lock); + spin_unlock(&autofs4_lock); spin_unlock(&sbi->fs_lock); follow: /* @@ -353,14 +355,14 @@ static int autofs4_revalidate(struct dentry *dentry, struct nameidata *nd) return 0; /* Check for a non-mountpoint directory with no contents */ - spin_lock(&dcache_lock); + spin_lock(&autofs4_lock); spin_lock(&dentry->d_lock); if (S_ISDIR(dentry->d_inode->i_mode) && !d_mountpoint(dentry) && list_empty(&dentry->d_subdirs)) { DPRINTK("dentry=%p %.*s, emptydir", dentry, dentry->d_name.len, dentry->d_name.name); spin_unlock(&dentry->d_lock); - spin_unlock(&dcache_lock); + spin_unlock(&autofs4_lock); /* The daemon never causes a mount to trigger */ if (oz_mode) @@ -377,7 +379,7 @@ static int autofs4_revalidate(struct dentry *dentry, struct nameidata *nd) return status; } spin_unlock(&dentry->d_lock); - spin_unlock(&dcache_lock); + spin_unlock(&autofs4_lock); return 1; } @@ -432,7 +434,7 @@ static struct dentry *autofs4_lookup_active(struct dentry *dentry) const unsigned char *str = name->name; struct list_head *p, *head; - spin_lock(&dcache_lock); + spin_lock(&autofs4_lock); spin_lock(&sbi->lookup_lock); head = &sbi->active_list; list_for_each(p, head) { @@ -465,14 +467,14 @@ static struct dentry *autofs4_lookup_active(struct dentry *dentry) dget_dlock(active); spin_unlock(&active->d_lock); spin_unlock(&sbi->lookup_lock); - spin_unlock(&dcache_lock); + spin_unlock(&autofs4_lock); return active; } next: spin_unlock(&active->d_lock); } spin_unlock(&sbi->lookup_lock); - spin_unlock(&dcache_lock); + spin_unlock(&autofs4_lock); return NULL; } @@ -487,7 +489,7 @@ static struct dentry *autofs4_lookup_expiring(struct dentry *dentry) const unsigned char *str = name->name; struct list_head *p, *head; - spin_lock(&dcache_lock); + spin_lock(&autofs4_lock); spin_lock(&sbi->lookup_lock); head = &sbi->expiring_list; list_for_each(p, head) { @@ -520,14 +522,14 @@ static struct dentry *autofs4_lookup_expiring(struct dentry *dentry) dget_dlock(expiring); spin_unlock(&expiring->d_lock); spin_unlock(&sbi->lookup_lock); - spin_unlock(&dcache_lock); + spin_unlock(&autofs4_lock); return expiring; } next: spin_unlock(&expiring->d_lock); } spin_unlock(&sbi->lookup_lock); - spin_unlock(&dcache_lock); + spin_unlock(&autofs4_lock); return NULL; } @@ -763,12 +765,12 @@ static int autofs4_dir_unlink(struct inode *dir, struct dentry *dentry) dir->i_mtime = CURRENT_TIME; - spin_lock(&dcache_lock); + spin_lock(&autofs4_lock); autofs4_add_expiring(dentry); spin_lock(&dentry->d_lock); __d_drop(dentry); spin_unlock(&dentry->d_lock); - spin_unlock(&dcache_lock); + spin_unlock(&autofs4_lock); return 0; } @@ -785,20 +787,20 @@ static int autofs4_dir_rmdir(struct inode *dir, struct dentry *dentry) if (!autofs4_oz_mode(sbi)) return -EACCES; - spin_lock(&dcache_lock); + spin_lock(&autofs4_lock); spin_lock(&sbi->lookup_lock); spin_lock(&dentry->d_lock); if (!list_empty(&dentry->d_subdirs)) { spin_unlock(&dentry->d_lock); spin_unlock(&sbi->lookup_lock); - spin_unlock(&dcache_lock); + spin_unlock(&autofs4_lock); return -ENOTEMPTY; } __autofs4_add_expiring(dentry); spin_unlock(&sbi->lookup_lock); __d_drop(dentry); spin_unlock(&dentry->d_lock); - spin_unlock(&dcache_lock); + spin_unlock(&autofs4_lock); if (atomic_dec_and_test(&ino->count)) { p_ino = autofs4_dentry_ino(dentry->d_parent); diff --git a/fs/autofs4/waitq.c b/fs/autofs4/waitq.c index 4be8f778a418..c5f8459c905e 100644 --- a/fs/autofs4/waitq.c +++ b/fs/autofs4/waitq.c @@ -194,14 +194,15 @@ static int autofs4_getpath(struct autofs_sb_info *sbi, rename_retry: buf = *name; len = 0; + seq = read_seqbegin(&rename_lock); rcu_read_lock(); - spin_lock(&dcache_lock); + spin_lock(&autofs4_lock); for (tmp = dentry ; tmp != root ; tmp = tmp->d_parent) len += tmp->d_name.len + 1; if (!len || --len > NAME_MAX) { - spin_unlock(&dcache_lock); + spin_unlock(&autofs4_lock); rcu_read_unlock(); if (read_seqretry(&rename_lock, seq)) goto rename_retry; @@ -217,7 +218,7 @@ rename_retry: p -= tmp->d_name.len; strncpy(p, tmp->d_name.name, tmp->d_name.len); } - spin_unlock(&dcache_lock); + spin_unlock(&autofs4_lock); rcu_read_unlock(); if (read_seqretry(&rename_lock, seq)) goto rename_retry; diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c index 2c924e8d85fe..58abc3da6111 100644 --- a/fs/ceph/dir.c +++ b/fs/ceph/dir.c @@ -112,7 +112,6 @@ static int __dcache_readdir(struct file *filp, dout("__dcache_readdir %p at %llu (last %p)\n", dir, filp->f_pos, last); - spin_lock(&dcache_lock); spin_lock(&parent->d_lock); /* start at beginning? */ @@ -156,7 +155,6 @@ more: dget_dlock(dentry); spin_unlock(&dentry->d_lock); spin_unlock(&parent->d_lock); - spin_unlock(&dcache_lock); dout(" %llu (%llu) dentry %p %.*s %p\n", di->offset, filp->f_pos, dentry, dentry->d_name.len, dentry->d_name.name, dentry->d_inode); @@ -182,21 +180,19 @@ more: filp->f_pos++; - /* make sure a dentry wasn't dropped while we didn't have dcache_lock */ + /* make sure a dentry wasn't dropped while we didn't have parent lock */ if (!ceph_i_test(dir, CEPH_I_COMPLETE)) { dout(" lost I_COMPLETE on %p; falling back to mds\n", dir); err = -EAGAIN; goto out; } - spin_lock(&dcache_lock); spin_lock(&parent->d_lock); p = p->prev; /* advance to next dentry */ goto more; out_unlock: spin_unlock(&parent->d_lock); - spin_unlock(&dcache_lock); out: if (last) dput(last); diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c index 2c6944473366..2a48cafc174b 100644 --- a/fs/ceph/inode.c +++ b/fs/ceph/inode.c @@ -841,7 +841,6 @@ static void ceph_set_dentry_offset(struct dentry *dn) di->offset = ceph_inode(inode)->i_max_offset++; spin_unlock(&inode->i_lock); - spin_lock(&dcache_lock); spin_lock(&dir->d_lock); spin_lock_nested(&dn->d_lock, DENTRY_D_LOCK_NESTED); list_move(&dn->d_u.d_child, &dir->d_subdirs); @@ -849,7 +848,6 @@ static void ceph_set_dentry_offset(struct dentry *dn) dn->d_u.d_child.prev, dn->d_u.d_child.next); spin_unlock(&dn->d_lock); spin_unlock(&dir->d_lock); - spin_unlock(&dcache_lock); } /* @@ -1233,13 +1231,11 @@ retry_lookup: goto retry_lookup; } else { /* reorder parent's d_subdirs */ - spin_lock(&dcache_lock); spin_lock(&parent->d_lock); spin_lock_nested(&dn->d_lock, DENTRY_D_LOCK_NESTED); list_move(&dn->d_u.d_child, &parent->d_subdirs); spin_unlock(&dn->d_lock); spin_unlock(&parent->d_lock); - spin_unlock(&dcache_lock); } di = dn->d_fsdata; diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c index 003698365ece..99b9a2cc14b7 100644 --- a/fs/cifs/inode.c +++ b/fs/cifs/inode.c @@ -809,17 +809,14 @@ inode_has_hashed_dentries(struct inode *inode) { struct dentry *dentry; - spin_lock(&dcache_lock); spin_lock(&dcache_inode_lock); list_for_each_entry(dentry, &inode->i_dentry, d_alias) { if (!d_unhashed(dentry) || IS_ROOT(dentry)) { spin_unlock(&dcache_inode_lock); - spin_unlock(&dcache_lock); return true; } } spin_unlock(&dcache_inode_lock); - spin_unlock(&dcache_lock); return false; } diff --git a/fs/coda/cache.c b/fs/coda/cache.c index 859393fca2b7..5525e1c660fd 100644 --- a/fs/coda/cache.c +++ b/fs/coda/cache.c @@ -93,7 +93,6 @@ static void coda_flag_children(struct dentry *parent, int flag) struct list_head *child; struct dentry *de; - spin_lock(&dcache_lock); spin_lock(&parent->d_lock); list_for_each(child, &parent->d_subdirs) { @@ -104,7 +103,6 @@ static void coda_flag_children(struct dentry *parent, int flag) coda_flag_inode(de->d_inode, flag); } spin_unlock(&parent->d_lock); - spin_unlock(&dcache_lock); return; } diff --git a/fs/configfs/configfs_internal.h b/fs/configfs/configfs_internal.h index e58b4c30e216..026cf68553a4 100644 --- a/fs/configfs/configfs_internal.h +++ b/fs/configfs/configfs_internal.h @@ -120,7 +120,6 @@ static inline struct config_item *configfs_get_config_item(struct dentry *dentry { struct config_item * item = NULL; - spin_lock(&dcache_lock); spin_lock(&dentry->d_lock); if (!d_unhashed(dentry)) { struct configfs_dirent * sd = dentry->d_fsdata; @@ -131,7 +130,6 @@ static inline struct config_item *configfs_get_config_item(struct dentry *dentry item = config_item_get(sd->s_element); } spin_unlock(&dentry->d_lock); - spin_unlock(&dcache_lock); return item; } diff --git a/fs/configfs/inode.c b/fs/configfs/inode.c index 79b37765d8ff..fb3a55fff82a 100644 --- a/fs/configfs/inode.c +++ b/fs/configfs/inode.c @@ -250,18 +250,14 @@ void configfs_drop_dentry(struct configfs_dirent * sd, struct dentry * parent) struct dentry * dentry = sd->s_dentry; if (dentry) { - spin_lock(&dcache_lock); spin_lock(&dentry->d_lock); if (!(d_unhashed(dentry) && dentry->d_inode)) { dget_locked_dlock(dentry); __d_drop(dentry); spin_unlock(&dentry->d_lock); - spin_unlock(&dcache_lock); simple_unlink(parent->d_inode, dentry); - } else { + } else spin_unlock(&dentry->d_lock); - spin_unlock(&dcache_lock); - } } } diff --git a/fs/dcache.c b/fs/dcache.c index a9bc4ecc21e1..0dbae053b664 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -54,11 +54,10 @@ * - d_alias, d_inode * * Ordering: - * dcache_lock - * dcache_inode_lock - * dentry->d_lock - * dcache_lru_lock - * dcache_hash_lock + * dcache_inode_lock + * dentry->d_lock + * dcache_lru_lock + * dcache_hash_lock * * If there is an ancestor relationship: * dentry->d_parent->...->d_parent->d_lock @@ -77,12 +76,10 @@ EXPORT_SYMBOL_GPL(sysctl_vfs_cache_pressure); __cacheline_aligned_in_smp DEFINE_SPINLOCK(dcache_inode_lock); static __cacheline_aligned_in_smp DEFINE_SPINLOCK(dcache_hash_lock); static __cacheline_aligned_in_smp DEFINE_SPINLOCK(dcache_lru_lock); -__cacheline_aligned_in_smp DEFINE_SPINLOCK(dcache_lock); __cacheline_aligned_in_smp DEFINE_SEQLOCK(rename_lock); EXPORT_SYMBOL(rename_lock); EXPORT_SYMBOL(dcache_inode_lock); -EXPORT_SYMBOL(dcache_lock); static struct kmem_cache *dentry_cache __read_mostly; @@ -139,7 +136,7 @@ static void __d_free(struct rcu_head *head) } /* - * no dcache_lock, please. + * no locks, please. */ static void d_free(struct dentry *dentry) { @@ -162,7 +159,6 @@ static void d_free(struct dentry *dentry) static void dentry_iput(struct dentry * dentry) __releases(dentry->d_lock) __releases(dcache_inode_lock) - __releases(dcache_lock) { struct inode *inode = dentry->d_inode; if (inode) { @@ -170,7 +166,6 @@ static void dentry_iput(struct dentry * dentry) list_del_init(&dentry->d_alias); spin_unlock(&dentry->d_lock); spin_unlock(&dcache_inode_lock); - spin_unlock(&dcache_lock); if (!inode->i_nlink) fsnotify_inoderemove(inode); if (dentry->d_op && dentry->d_op->d_iput) @@ -180,7 +175,6 @@ static void dentry_iput(struct dentry * dentry) } else { spin_unlock(&dentry->d_lock); spin_unlock(&dcache_inode_lock); - spin_unlock(&dcache_lock); } } @@ -235,14 +229,13 @@ static void dentry_lru_move_tail(struct dentry *dentry) * * If this is the root of the dentry tree, return NULL. * - * dcache_lock and d_lock and d_parent->d_lock must be held by caller, and - * are dropped by d_kill. + * dentry->d_lock and parent->d_lock must be held by caller, and are dropped by + * d_kill. */ static struct dentry *d_kill(struct dentry *dentry, struct dentry *parent) __releases(dentry->d_lock) __releases(parent->d_lock) __releases(dcache_inode_lock) - __releases(dcache_lock) { dentry->d_parent = NULL; list_del(&dentry->d_u.d_child); @@ -285,11 +278,9 @@ EXPORT_SYMBOL(__d_drop); void d_drop(struct dentry *dentry) { - spin_lock(&dcache_lock); spin_lock(&dentry->d_lock); __d_drop(dentry); spin_unlock(&dentry->d_lock); - spin_unlock(&dcache_lock); } EXPORT_SYMBOL(d_drop); @@ -337,21 +328,10 @@ repeat: else parent = dentry->d_parent; if (dentry->d_count == 1) { - if (!spin_trylock(&dcache_lock)) { - /* - * Something of a livelock possibility we could avoid - * by taking dcache_lock and trying again, but we - * want to reduce dcache_lock anyway so this will - * get improved. - */ -drop1: - spin_unlock(&dentry->d_lock); - goto repeat; - } if (!spin_trylock(&dcache_inode_lock)) { drop2: - spin_unlock(&dcache_lock); - goto drop1; + spin_unlock(&dentry->d_lock); + goto repeat; } if (parent && !spin_trylock(&parent->d_lock)) { spin_unlock(&dcache_inode_lock); @@ -363,7 +343,6 @@ drop2: spin_unlock(&dentry->d_lock); if (parent) spin_unlock(&parent->d_lock); - spin_unlock(&dcache_lock); return; } @@ -387,7 +366,6 @@ drop2: if (parent) spin_unlock(&parent->d_lock); spin_unlock(&dcache_inode_lock); - spin_unlock(&dcache_lock); return; unhash_it: @@ -418,11 +396,9 @@ int d_invalidate(struct dentry * dentry) /* * If it's already been dropped, return OK. */ - spin_lock(&dcache_lock); spin_lock(&dentry->d_lock); if (d_unhashed(dentry)) { spin_unlock(&dentry->d_lock); - spin_unlock(&dcache_lock); return 0; } /* @@ -431,9 +407,7 @@ int d_invalidate(struct dentry * dentry) */ if (!list_empty(&dentry->d_subdirs)) { spin_unlock(&dentry->d_lock); - spin_unlock(&dcache_lock); shrink_dcache_parent(dentry); - spin_lock(&dcache_lock); spin_lock(&dentry->d_lock); } @@ -450,19 +424,17 @@ int d_invalidate(struct dentry * dentry) if (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; } EXPORT_SYMBOL(d_invalidate); -/* This must be called with dcache_lock and d_lock held */ +/* This must be called with d_lock held */ static inline struct dentry * __dget_locked_dlock(struct dentry *dentry) { dentry->d_count++; @@ -470,7 +442,7 @@ static inline struct dentry * __dget_locked_dlock(struct dentry *dentry) return dentry; } -/* This should be called _only_ with dcache_lock held */ +/* This must be called with d_lock held */ static inline struct dentry * __dget_locked(struct dentry *dentry) { spin_lock(&dentry->d_lock); @@ -575,11 +547,9 @@ struct dentry *d_find_alias(struct inode *inode) struct dentry *de = NULL; if (!list_empty(&inode->i_dentry)) { - spin_lock(&dcache_lock); spin_lock(&dcache_inode_lock); de = __d_find_alias(inode, 0); spin_unlock(&dcache_inode_lock); - spin_unlock(&dcache_lock); } return de; } @@ -593,7 +563,6 @@ void d_prune_aliases(struct inode *inode) { struct dentry *dentry; restart: - spin_lock(&dcache_lock); spin_lock(&dcache_inode_lock); list_for_each_entry(dentry, &inode->i_dentry, d_alias) { spin_lock(&dentry->d_lock); @@ -602,14 +571,12 @@ restart: __d_drop(dentry); spin_unlock(&dentry->d_lock); spin_unlock(&dcache_inode_lock); - spin_unlock(&dcache_lock); dput(dentry); goto restart; } spin_unlock(&dentry->d_lock); } spin_unlock(&dcache_inode_lock); - spin_unlock(&dcache_lock); } EXPORT_SYMBOL(d_prune_aliases); @@ -625,17 +592,14 @@ static void prune_one_dentry(struct dentry *dentry, struct dentry *parent) __releases(dentry->d_lock) __releases(parent->d_lock) __releases(dcache_inode_lock) - __releases(dcache_lock) { __d_drop(dentry); dentry = d_kill(dentry, parent); /* - * Prune ancestors. Locking is simpler than in dput(), - * because dcache_lock needs to be taken anyway. + * Prune ancestors. */ while (dentry) { - spin_lock(&dcache_lock); spin_lock(&dcache_inode_lock); again: spin_lock(&dentry->d_lock); @@ -653,7 +617,6 @@ again: spin_unlock(&parent->d_lock); spin_unlock(&dentry->d_lock); spin_unlock(&dcache_inode_lock); - spin_unlock(&dcache_lock); return; } @@ -702,8 +665,7 @@ relock: spin_unlock(&dcache_lru_lock); prune_one_dentry(dentry, parent); - /* dcache_lock, dcache_inode_lock and dentry->d_lock dropped */ - spin_lock(&dcache_lock); + /* dcache_inode_lock and dentry->d_lock dropped */ spin_lock(&dcache_inode_lock); spin_lock(&dcache_lru_lock); } @@ -725,7 +687,6 @@ static void __shrink_dcache_sb(struct super_block *sb, int *count, int flags) LIST_HEAD(tmp); int cnt = *count; - spin_lock(&dcache_lock); spin_lock(&dcache_inode_lock); relock: spin_lock(&dcache_lru_lock); @@ -766,7 +727,6 @@ relock: list_splice(&referenced, &sb->s_dentry_lru); spin_unlock(&dcache_lru_lock); spin_unlock(&dcache_inode_lock); - spin_unlock(&dcache_lock); } /** @@ -788,7 +748,6 @@ static void prune_dcache(int count) if (unused == 0 || count == 0) return; - spin_lock(&dcache_lock); if (count >= unused) prune_ratio = 1; else @@ -825,11 +784,9 @@ static void prune_dcache(int count) 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); } up_read(&sb->s_umount); } @@ -845,7 +802,6 @@ static void prune_dcache(int count) if (p) __put_super(p); spin_unlock(&sb_lock); - spin_unlock(&dcache_lock); } /** @@ -859,7 +815,6 @@ void shrink_dcache_sb(struct super_block *sb) { LIST_HEAD(tmp); - spin_lock(&dcache_lock); spin_lock(&dcache_inode_lock); spin_lock(&dcache_lru_lock); while (!list_empty(&sb->s_dentry_lru)) { @@ -868,7 +823,6 @@ void shrink_dcache_sb(struct super_block *sb) } spin_unlock(&dcache_lru_lock); spin_unlock(&dcache_inode_lock); - spin_unlock(&dcache_lock); } EXPORT_SYMBOL(shrink_dcache_sb); @@ -885,12 +839,10 @@ static void shrink_dcache_for_umount_subtree(struct dentry *dentry) BUG_ON(!IS_ROOT(dentry)); /* detach this root from the system */ - spin_lock(&dcache_lock); spin_lock(&dentry->d_lock); dentry_lru_del(dentry); __d_drop(dentry); spin_unlock(&dentry->d_lock); - spin_unlock(&dcache_lock); for (;;) { /* descend to the first leaf in the current subtree */ @@ -899,7 +851,6 @@ static void shrink_dcache_for_umount_subtree(struct dentry *dentry) /* this is a branch with children - detach all of them * from the system in one go */ - spin_lock(&dcache_lock); spin_lock(&dentry->d_lock); list_for_each_entry(loop, &dentry->d_subdirs, d_u.d_child) { @@ -910,7 +861,6 @@ static void shrink_dcache_for_umount_subtree(struct dentry *dentry) spin_unlock(&loop->d_lock); } spin_unlock(&dentry->d_lock); - spin_unlock(&dcache_lock); /* move to the first child */ dentry = list_entry(dentry->d_subdirs.next, @@ -977,8 +927,7 @@ static void shrink_dcache_for_umount_subtree(struct dentry *dentry) /* * 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: + * - we don't need to use dentry->d_lock 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 @@ -1029,7 +978,6 @@ rename_retry: this_parent = parent; seq = read_seqbegin(&rename_lock); - spin_lock(&dcache_lock); if (d_mountpoint(parent)) goto positive; spin_lock(&this_parent->d_lock); @@ -1075,7 +1023,6 @@ resume: if (this_parent != child->d_parent || read_seqretry(&rename_lock, seq)) { spin_unlock(&this_parent->d_lock); - spin_unlock(&dcache_lock); rcu_read_unlock(); goto rename_retry; } @@ -1084,12 +1031,10 @@ resume: goto resume; } spin_unlock(&this_parent->d_lock); - spin_unlock(&dcache_lock); if (read_seqretry(&rename_lock, seq)) goto rename_retry; return 0; /* No mount points found in tree */ positive: - spin_unlock(&dcache_lock); if (read_seqretry(&rename_lock, seq)) goto rename_retry; return 1; @@ -1121,7 +1066,6 @@ rename_retry: this_parent = parent; seq = read_seqbegin(&rename_lock); - spin_lock(&dcache_lock); spin_lock(&this_parent->d_lock); repeat: next = this_parent->d_subdirs.next; @@ -1185,7 +1129,6 @@ resume: if (this_parent != child->d_parent || read_seqretry(&rename_lock, seq)) { spin_unlock(&this_parent->d_lock); - spin_unlock(&dcache_lock); rcu_read_unlock(); goto rename_retry; } @@ -1195,7 +1138,6 @@ resume: } out: spin_unlock(&this_parent->d_lock); - spin_unlock(&dcache_lock); if (read_seqretry(&rename_lock, seq)) goto rename_retry; return found; @@ -1297,7 +1239,6 @@ struct dentry *d_alloc(struct dentry * parent, const struct qstr *name) INIT_LIST_HEAD(&dentry->d_u.d_child); if (parent) { - spin_lock(&dcache_lock); spin_lock(&parent->d_lock); spin_lock_nested(&dentry->d_lock, DENTRY_D_LOCK_NESTED); dentry->d_parent = dget_dlock(parent); @@ -1305,7 +1246,6 @@ struct dentry *d_alloc(struct dentry * parent, const struct qstr *name) list_add(&dentry->d_u.d_child, &parent->d_subdirs); spin_unlock(&dentry->d_lock); spin_unlock(&parent->d_lock); - spin_unlock(&dcache_lock); } this_cpu_inc(nr_dentry); @@ -1325,7 +1265,6 @@ struct dentry *d_alloc_name(struct dentry *parent, const char *name) } EXPORT_SYMBOL(d_alloc_name); -/* the caller must hold dcache_lock */ static void __d_instantiate(struct dentry *dentry, struct inode *inode) { spin_lock(&dentry->d_lock); @@ -1354,11 +1293,9 @@ static void __d_instantiate(struct dentry *dentry, struct inode *inode) void d_instantiate(struct dentry *entry, struct inode * inode) { BUG_ON(!list_empty(&entry->d_alias)); - spin_lock(&dcache_lock); spin_lock(&dcache_inode_lock); __d_instantiate(entry, inode); spin_unlock(&dcache_inode_lock); - spin_unlock(&dcache_lock); security_d_instantiate(entry, inode); } EXPORT_SYMBOL(d_instantiate); @@ -1422,11 +1359,9 @@ struct dentry *d_instantiate_unique(struct dentry *entry, struct inode *inode) BUG_ON(!list_empty(&entry->d_alias)); - spin_lock(&dcache_lock); spin_lock(&dcache_inode_lock); result = __d_instantiate_unique(entry, inode); spin_unlock(&dcache_inode_lock); - spin_unlock(&dcache_lock); if (!result) { security_d_instantiate(entry, inode); @@ -1515,12 +1450,11 @@ struct dentry *d_obtain_alias(struct inode *inode) } tmp->d_parent = tmp; /* make sure dput doesn't croak */ - spin_lock(&dcache_lock); + spin_lock(&dcache_inode_lock); res = __d_find_alias(inode, 0); if (res) { spin_unlock(&dcache_inode_lock); - spin_unlock(&dcache_lock); dput(tmp); goto out_iput; } @@ -1538,7 +1472,6 @@ struct dentry *d_obtain_alias(struct inode *inode) spin_unlock(&tmp->d_lock); spin_unlock(&dcache_inode_lock); - spin_unlock(&dcache_lock); return tmp; out_iput: @@ -1568,21 +1501,18 @@ struct dentry *d_splice_alias(struct inode *inode, struct dentry *dentry) struct dentry *new = NULL; if (inode && S_ISDIR(inode->i_mode)) { - spin_lock(&dcache_lock); spin_lock(&dcache_inode_lock); new = __d_find_alias(inode, 1); if (new) { BUG_ON(!(new->d_flags & DCACHE_DISCONNECTED)); spin_unlock(&dcache_inode_lock); - spin_unlock(&dcache_lock); security_d_instantiate(new, inode); d_move(new, dentry); iput(inode); } else { - /* already taking dcache_lock, so d_add() by hand */ + /* already taking dcache_inode_lock, so d_add() by hand */ __d_instantiate(dentry, inode); spin_unlock(&dcache_inode_lock); - spin_unlock(&dcache_lock); security_d_instantiate(dentry, inode); d_rehash(dentry); } @@ -1655,12 +1585,10 @@ struct dentry *d_add_ci(struct dentry *dentry, struct inode *inode, * Negative dentry: instantiate it unless the inode is a directory and * already has a dentry. */ - spin_lock(&dcache_lock); spin_lock(&dcache_inode_lock); if (!S_ISDIR(inode->i_mode) || list_empty(&inode->i_dentry)) { __d_instantiate(found, inode); spin_unlock(&dcache_inode_lock); - spin_unlock(&dcache_lock); security_d_instantiate(found, inode); return found; } @@ -1672,7 +1600,6 @@ struct dentry *d_add_ci(struct dentry *dentry, struct inode *inode, new = list_entry(inode->i_dentry.next, struct dentry, d_alias); dget_locked(new); spin_unlock(&dcache_inode_lock); - spin_unlock(&dcache_lock); security_d_instantiate(found, inode); d_move(new, found); iput(inode); @@ -1843,7 +1770,6 @@ int d_validate(struct dentry *dentry, struct dentry *dparent) { struct dentry *child; - spin_lock(&dcache_lock); spin_lock(&dparent->d_lock); list_for_each_entry(child, &dparent->d_subdirs, d_u.d_child) { if (dentry == child) { @@ -1851,12 +1777,10 @@ int d_validate(struct dentry *dentry, struct dentry *dparent) __dget_locked_dlock(dentry); spin_unlock(&dentry->d_lock); spin_unlock(&dparent->d_lock); - spin_unlock(&dcache_lock); return 1; } } spin_unlock(&dparent->d_lock); - spin_unlock(&dcache_lock); return 0; } @@ -1889,7 +1813,6 @@ void d_delete(struct dentry * dentry) /* * Are we the only user? */ - spin_lock(&dcache_lock); spin_lock(&dcache_inode_lock); spin_lock(&dentry->d_lock); isdir = S_ISDIR(dentry->d_inode->i_mode); @@ -1905,7 +1828,6 @@ void d_delete(struct dentry * dentry) spin_unlock(&dentry->d_lock); spin_unlock(&dcache_inode_lock); - spin_unlock(&dcache_lock); fsnotify_nameremove(dentry, isdir); } @@ -1932,13 +1854,11 @@ static void _d_rehash(struct dentry * entry) void d_rehash(struct dentry * entry) { - spin_lock(&dcache_lock); spin_lock(&entry->d_lock); spin_lock(&dcache_hash_lock); _d_rehash(entry); spin_unlock(&dcache_hash_lock); spin_unlock(&entry->d_lock); - spin_unlock(&dcache_lock); } EXPORT_SYMBOL(d_rehash); @@ -1961,11 +1881,9 @@ void dentry_update_name_case(struct dentry *dentry, struct qstr *name) BUG_ON(!mutex_is_locked(&dentry->d_inode->i_mutex)); BUG_ON(dentry->d_name.len != name->len); /* d_lookup gives this */ - spin_lock(&dcache_lock); spin_lock(&dentry->d_lock); memcpy((unsigned char *)dentry->d_name.name, name->name, name->len); spin_unlock(&dentry->d_lock); - spin_unlock(&dcache_lock); } EXPORT_SYMBOL(dentry_update_name_case); @@ -2058,14 +1976,14 @@ static void dentry_unlock_parents_for_move(struct dentry *dentry, * The hash value has to match the hash queue that the dentry is on.. */ /* - * d_move_locked - move a dentry + * 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. */ -static void d_move_locked(struct dentry * dentry, struct dentry * target) +void d_move(struct dentry * dentry, struct dentry * target) { if (!dentry->d_inode) printk(KERN_WARNING "VFS: moving negative dcache entry\n"); @@ -2114,22 +2032,6 @@ static void d_move_locked(struct dentry * dentry, struct dentry * target) spin_unlock(&dentry->d_lock); write_sequnlock(&rename_lock); } - -/** - * 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); - spin_unlock(&dcache_lock); -} EXPORT_SYMBOL(d_move); /** @@ -2155,13 +2057,12 @@ struct dentry *d_ancestor(struct dentry *p1, struct dentry *p2) * 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 + * dentry->d_parent->d_inode->i_mutex and the dcache_inode_lock * * Note: If ever the locking in lock_rename() changes, then please * remember to update this too... */ static struct dentry *__d_unalias(struct dentry *dentry, struct dentry *alias) - __releases(dcache_lock) __releases(dcache_inode_lock) { struct mutex *m1 = NULL, *m2 = NULL; @@ -2185,11 +2086,10 @@ static struct dentry *__d_unalias(struct dentry *dentry, struct dentry *alias) goto out_err; m2 = &alias->d_parent->d_inode->i_mutex; out_unalias: - d_move_locked(alias, dentry); + d_move(alias, dentry); ret = alias; out_err: spin_unlock(&dcache_inode_lock); - spin_unlock(&dcache_lock); if (m2) mutex_unlock(m2); if (m1) @@ -2249,7 +2149,6 @@ struct dentry *d_materialise_unique(struct dentry *dentry, struct inode *inode) BUG_ON(!d_unhashed(dentry)); - spin_lock(&dcache_lock); spin_lock(&dcache_inode_lock); if (!inode) { @@ -2295,7 +2194,6 @@ found: spin_unlock(&dcache_hash_lock); spin_unlock(&actual->d_lock); spin_unlock(&dcache_inode_lock); - spin_unlock(&dcache_lock); out_nolock: if (actual == dentry) { security_d_instantiate(dentry, inode); @@ -2307,7 +2205,6 @@ out_nolock: shouldnt_be_hashed: spin_unlock(&dcache_inode_lock); - spin_unlock(&dcache_lock); BUG(); } EXPORT_SYMBOL_GPL(d_materialise_unique); @@ -2421,11 +2318,9 @@ char *__d_path(const struct path *path, struct path *root, int error; prepend(&res, &buflen, "\0", 1); - spin_lock(&dcache_lock); write_seqlock(&rename_lock); error = prepend_path(path, root, &res, &buflen); write_sequnlock(&rename_lock); - spin_unlock(&dcache_lock); if (error) return ERR_PTR(error); @@ -2487,14 +2382,12 @@ char *d_path(const struct path *path, char *buf, int buflen) return path->dentry->d_op->d_dname(path->dentry, buf, buflen); get_fs_root(current->fs, &root); - spin_lock(&dcache_lock); write_seqlock(&rename_lock); tmp = root; error = path_with_deleted(path, &tmp, &res, &buflen); if (error) res = ERR_PTR(error); write_sequnlock(&rename_lock); - spin_unlock(&dcache_lock); path_put(&root); return res; } @@ -2520,14 +2413,12 @@ char *d_path_with_unreachable(const struct path *path, char *buf, int buflen) return path->dentry->d_op->d_dname(path->dentry, buf, buflen); get_fs_root(current->fs, &root); - spin_lock(&dcache_lock); write_seqlock(&rename_lock); tmp = root; error = path_with_deleted(path, &tmp, &res, &buflen); if (!error && !path_equal(&tmp, &root)) error = prepend_unreachable(&res, &buflen); write_sequnlock(&rename_lock); - spin_unlock(&dcache_lock); path_put(&root); if (error) res = ERR_PTR(error); @@ -2594,11 +2485,9 @@ char *dentry_path_raw(struct dentry *dentry, char *buf, int buflen) { char *retval; - spin_lock(&dcache_lock); write_seqlock(&rename_lock); retval = __dentry_path(dentry, buf, buflen); write_sequnlock(&rename_lock); - spin_unlock(&dcache_lock); return retval; } @@ -2609,7 +2498,6 @@ char *dentry_path(struct dentry *dentry, char *buf, int buflen) char *p = NULL; char *retval; - spin_lock(&dcache_lock); write_seqlock(&rename_lock); if (d_unlinked(dentry)) { p = buf + buflen; @@ -2619,12 +2507,10 @@ char *dentry_path(struct dentry *dentry, char *buf, int buflen) } retval = __dentry_path(dentry, buf, buflen); write_sequnlock(&rename_lock); - spin_unlock(&dcache_lock); if (!IS_ERR(retval) && p) *p = '/'; /* restore '/' overriden with '\0' */ return retval; Elong: - spin_unlock(&dcache_lock); return ERR_PTR(-ENAMETOOLONG); } @@ -2658,7 +2544,6 @@ SYSCALL_DEFINE2(getcwd, char __user *, buf, unsigned long, size) get_fs_root_and_pwd(current->fs, &root, &pwd); error = -ENOENT; - spin_lock(&dcache_lock); write_seqlock(&rename_lock); if (!d_unlinked(pwd.dentry)) { unsigned long len; @@ -2669,7 +2554,6 @@ SYSCALL_DEFINE2(getcwd, char __user *, buf, unsigned long, size) prepend(&cwd, &buflen, "\0", 1); error = prepend_path(&pwd, &tmp, &cwd, &buflen); write_sequnlock(&rename_lock); - spin_unlock(&dcache_lock); if (error) goto out; @@ -2690,7 +2574,6 @@ SYSCALL_DEFINE2(getcwd, char __user *, buf, unsigned long, size) } } else { write_sequnlock(&rename_lock); - spin_unlock(&dcache_lock); } out: @@ -2776,7 +2659,6 @@ void d_genocide(struct dentry *root) rename_retry: this_parent = root; seq = read_seqbegin(&rename_lock); - spin_lock(&dcache_lock); spin_lock(&this_parent->d_lock); repeat: next = this_parent->d_subdirs.next; @@ -2823,7 +2705,6 @@ resume: if (this_parent != child->d_parent || read_seqretry(&rename_lock, seq)) { spin_unlock(&this_parent->d_lock); - spin_unlock(&dcache_lock); rcu_read_unlock(); goto rename_retry; } @@ -2832,7 +2713,6 @@ resume: goto resume; } spin_unlock(&this_parent->d_lock); - spin_unlock(&dcache_lock); if (read_seqretry(&rename_lock, seq)) goto rename_retry; } diff --git a/fs/exportfs/expfs.c b/fs/exportfs/expfs.c index 84b8c460a781..53a5c08fb63c 100644 --- a/fs/exportfs/expfs.c +++ b/fs/exportfs/expfs.c @@ -47,24 +47,20 @@ find_acceptable_alias(struct dentry *result, if (acceptable(context, result)) return result; - spin_lock(&dcache_lock); spin_lock(&dcache_inode_lock); list_for_each_entry(dentry, &result->d_inode->i_dentry, d_alias) { dget_locked(dentry); spin_unlock(&dcache_inode_lock); - spin_unlock(&dcache_lock); if (toput) dput(toput); if (dentry != result && acceptable(context, dentry)) { dput(result); return dentry; } - spin_lock(&dcache_lock); spin_lock(&dcache_inode_lock); toput = dentry; } spin_unlock(&dcache_inode_lock); - spin_unlock(&dcache_lock); if (toput) dput(toput); diff --git a/fs/libfs.c b/fs/libfs.c index cc4794914b52..28b36663c44e 100644 --- a/fs/libfs.c +++ b/fs/libfs.c @@ -100,7 +100,6 @@ loff_t dcache_dir_lseek(struct file *file, loff_t offset, int origin) struct dentry *cursor = file->private_data; loff_t n = file->f_pos - 2; - spin_lock(&dcache_lock); spin_lock(&dentry->d_lock); /* d_lock not required for cursor */ list_del(&cursor->d_u.d_child); @@ -116,7 +115,6 @@ loff_t dcache_dir_lseek(struct file *file, loff_t offset, int origin) } list_add_tail(&cursor->d_u.d_child, p); spin_unlock(&dentry->d_lock); - spin_unlock(&dcache_lock); } } mutex_unlock(&dentry->d_inode->i_mutex); @@ -159,7 +157,6 @@ int dcache_readdir(struct file * filp, void * dirent, filldir_t filldir) i++; /* fallthrough */ default: - spin_lock(&dcache_lock); spin_lock(&dentry->d_lock); if (filp->f_pos == 2) list_move(q, &dentry->d_subdirs); @@ -175,13 +172,11 @@ int dcache_readdir(struct file * filp, void * dirent, filldir_t filldir) spin_unlock(&next->d_lock); spin_unlock(&dentry->d_lock); - spin_unlock(&dcache_lock); if (filldir(dirent, next->d_name.name, next->d_name.len, filp->f_pos, next->d_inode->i_ino, dt_type(next->d_inode)) < 0) return 0; - spin_lock(&dcache_lock); spin_lock(&dentry->d_lock); spin_lock_nested(&next->d_lock, DENTRY_D_LOCK_NESTED); /* next is still alive */ @@ -191,7 +186,6 @@ int dcache_readdir(struct file * filp, void * dirent, filldir_t filldir) filp->f_pos++; } spin_unlock(&dentry->d_lock); - spin_unlock(&dcache_lock); } return 0; } @@ -285,7 +279,6 @@ int simple_empty(struct dentry *dentry) struct dentry *child; int ret = 0; - spin_lock(&dcache_lock); spin_lock(&dentry->d_lock); list_for_each_entry(child, &dentry->d_subdirs, d_u.d_child) { spin_lock_nested(&child->d_lock, DENTRY_D_LOCK_NESTED); @@ -298,7 +291,6 @@ int simple_empty(struct dentry *dentry) ret = 1; out: spin_unlock(&dentry->d_lock); - spin_unlock(&dcache_lock); return ret; } diff --git a/fs/namei.c b/fs/namei.c index cbfa5fb31072..5642bc2be418 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -612,8 +612,8 @@ int follow_up(struct path *path) return 1; } -/* no need for dcache_lock, as serialization is taken care in - * namespace.c +/* + * serialization is taken care of in namespace.c */ static int __follow_mount(struct path *path) { @@ -645,9 +645,6 @@ static void follow_mount(struct path *path) } } -/* no need for dcache_lock, as serialization is taken care in - * namespace.c - */ int follow_down(struct path *path) { struct vfsmount *mounted; @@ -2131,12 +2128,10 @@ void dentry_unhash(struct dentry *dentry) { dget(dentry); shrink_dcache_parent(dentry); - spin_lock(&dcache_lock); spin_lock(&dentry->d_lock); if (dentry->d_count == 2) __d_drop(dentry); spin_unlock(&dentry->d_lock); - spin_unlock(&dcache_lock); } int vfs_rmdir(struct inode *dir, struct dentry *dentry) diff --git a/fs/ncpfs/dir.c b/fs/ncpfs/dir.c index 102278ed38bd..de15c533311c 100644 --- a/fs/ncpfs/dir.c +++ b/fs/ncpfs/dir.c @@ -391,7 +391,6 @@ ncp_dget_fpos(struct dentry *dentry, struct dentry *parent, unsigned long fpos) } /* If a pointer is invalid, we search the dentry. */ - spin_lock(&dcache_lock); spin_lock(&parent->d_lock); next = parent->d_subdirs.next; while (next != &parent->d_subdirs) { @@ -402,13 +401,11 @@ ncp_dget_fpos(struct dentry *dentry, struct dentry *parent, unsigned long fpos) else dent = NULL; spin_unlock(&parent->d_lock); - spin_unlock(&dcache_lock); goto out; } next = next->next; } spin_unlock(&parent->d_lock); - spin_unlock(&dcache_lock); return NULL; out: diff --git a/fs/ncpfs/ncplib_kernel.h b/fs/ncpfs/ncplib_kernel.h index c4b718ff9a6b..1220df75ff22 100644 --- a/fs/ncpfs/ncplib_kernel.h +++ b/fs/ncpfs/ncplib_kernel.h @@ -193,7 +193,6 @@ ncp_renew_dentries(struct dentry *parent) struct list_head *next; struct dentry *dentry; - spin_lock(&dcache_lock); spin_lock(&parent->d_lock); next = parent->d_subdirs.next; while (next != &parent->d_subdirs) { @@ -207,7 +206,6 @@ ncp_renew_dentries(struct dentry *parent) next = next->next; } spin_unlock(&parent->d_lock); - spin_unlock(&dcache_lock); } static inline void @@ -217,7 +215,6 @@ ncp_invalidate_dircache_entries(struct dentry *parent) struct list_head *next; struct dentry *dentry; - spin_lock(&dcache_lock); spin_lock(&parent->d_lock); next = parent->d_subdirs.next; while (next != &parent->d_subdirs) { @@ -227,7 +224,6 @@ ncp_invalidate_dircache_entries(struct dentry *parent) next = next->next; } spin_unlock(&parent->d_lock); - spin_unlock(&dcache_lock); } struct ncp_cache_head { diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c index 12de824edb5c..eb77471b8823 100644 --- a/fs/nfs/dir.c +++ b/fs/nfs/dir.c @@ -1718,11 +1718,9 @@ static int nfs_unlink(struct inode *dir, struct dentry *dentry) dfprintk(VFS, "NFS: unlink(%s/%ld, %s)\n", dir->i_sb->s_id, dir->i_ino, dentry->d_name.name); - spin_lock(&dcache_lock); spin_lock(&dentry->d_lock); if (dentry->d_count > 1) { spin_unlock(&dentry->d_lock); - spin_unlock(&dcache_lock); /* Start asynchronous writeout of the inode */ write_inode_now(dentry->d_inode, 0); error = nfs_sillyrename(dir, dentry); @@ -1733,7 +1731,6 @@ static int nfs_unlink(struct inode *dir, struct dentry *dentry) need_rehash = 1; } spin_unlock(&dentry->d_lock); - spin_unlock(&dcache_lock); error = nfs_safe_remove(dentry); if (!error || error == -ENOENT) { nfs_set_verifier(dentry, nfs_save_change_attribute(dir)); diff --git a/fs/nfs/getroot.c b/fs/nfs/getroot.c index 850f67d5f0ac..b3e36c3430de 100644 --- a/fs/nfs/getroot.c +++ b/fs/nfs/getroot.c @@ -63,13 +63,11 @@ static int nfs_superblock_set_dummy_root(struct super_block *sb, struct inode *i * This again causes shrink_dcache_for_umount_subtree() to * Oops, since the test for IS_ROOT() will fail. */ - spin_lock(&dcache_lock); spin_lock(&dcache_inode_lock); spin_lock(&sb->s_root->d_lock); list_del_init(&sb->s_root->d_alias); spin_unlock(&sb->s_root->d_lock); spin_unlock(&dcache_inode_lock); - spin_unlock(&dcache_lock); } return 0; } diff --git a/fs/nfs/namespace.c b/fs/nfs/namespace.c index 78c0ebb0b07c..74aaf3963c10 100644 --- a/fs/nfs/namespace.c +++ b/fs/nfs/namespace.c @@ -60,7 +60,6 @@ rename_retry: seq = read_seqbegin(&rename_lock); rcu_read_lock(); - spin_lock(&dcache_lock); while (!IS_ROOT(dentry) && dentry != droot) { namelen = dentry->d_name.len; buflen -= namelen + 1; @@ -71,7 +70,6 @@ rename_retry: *--end = '/'; dentry = dentry->d_parent; } - spin_unlock(&dcache_lock); rcu_read_unlock(); if (read_seqretry(&rename_lock, seq)) goto rename_retry; @@ -91,7 +89,6 @@ rename_retry: memcpy(end, base, namelen); return end; Elong_unlock: - spin_unlock(&dcache_lock); rcu_read_unlock(); if (read_seqretry(&rename_lock, seq)) goto rename_retry; diff --git a/fs/notify/fsnotify.c b/fs/notify/fsnotify.c index ae769fc9b66c..9be6ec1f36d8 100644 --- a/fs/notify/fsnotify.c +++ b/fs/notify/fsnotify.c @@ -59,7 +59,6 @@ void __fsnotify_update_child_dentry_flags(struct inode *inode) /* determine if the children should tell inode about their events */ watched = fsnotify_inode_watches_children(inode); - spin_lock(&dcache_lock); spin_lock(&dcache_inode_lock); /* run all of the dentries associated with this inode. Since this is a * directory, there damn well better only be one item on this list */ @@ -84,7 +83,6 @@ void __fsnotify_update_child_dentry_flags(struct inode *inode) spin_unlock(&alias->d_lock); } spin_unlock(&dcache_inode_lock); - spin_unlock(&dcache_lock); } /* Notify this dentry's parent about a child's events. */ diff --git a/fs/ocfs2/dcache.c b/fs/ocfs2/dcache.c index c31b5c647ac7..b7de749bdd12 100644 --- a/fs/ocfs2/dcache.c +++ b/fs/ocfs2/dcache.c @@ -169,7 +169,6 @@ struct dentry *ocfs2_find_local_alias(struct inode *inode, struct list_head *p; struct dentry *dentry = NULL; - spin_lock(&dcache_lock); spin_lock(&dcache_inode_lock); list_for_each(p, &inode->i_dentry) { dentry = list_entry(p, struct dentry, d_alias); @@ -189,7 +188,6 @@ struct dentry *ocfs2_find_local_alias(struct inode *inode, } spin_unlock(&dcache_inode_lock); - spin_unlock(&dcache_lock); return dentry; } diff --git a/include/linux/dcache.h b/include/linux/dcache.h index c963ebada922..a2ceb94b0e38 100644 --- a/include/linux/dcache.h +++ b/include/linux/dcache.h @@ -183,7 +183,6 @@ struct dentry_operations { #define DCACHE_GENOCIDE 0x0200 extern spinlock_t dcache_inode_lock; -extern spinlock_t dcache_lock; extern seqlock_t rename_lock; static inline int dname_external(struct dentry *dentry) @@ -296,8 +295,8 @@ extern char *dentry_path(struct dentry *, char *, int); * destroyed when it has references. dget() should never be * called for dentries with zero reference counter. For these cases * (preferably none, functions in dcache.c are sufficient for normal - * needs and they take necessary precautions) you should hold dcache_lock - * and call dget_locked() instead of dget(). + * needs and they take necessary precautions) you should hold d_lock + * and call dget_dlock() instead of dget(). */ static inline struct dentry *dget_dlock(struct dentry *dentry) { diff --git a/include/linux/fs.h b/include/linux/fs.h index 090f0eacde29..296cf2fde945 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1378,7 +1378,7 @@ struct super_block { #else struct list_head s_files; #endif - /* s_dentry_lru and s_nr_dentry_unused are protected by dcache_lock */ + /* s_dentry_lru, s_nr_dentry_unused protected by dcache.c lru locks */ struct list_head s_dentry_lru; /* unused dentry lru */ int s_nr_dentry_unused; /* # of dentry on lru */ @@ -2446,6 +2446,10 @@ static inline ino_t parent_ino(struct dentry *dentry) { ino_t res; + /* + * Don't strictly need d_lock here? If the parent ino could change + * then surely we'd have a deeper race in the caller? + */ spin_lock(&dentry->d_lock); res = dentry->d_parent->d_inode->i_ino; spin_unlock(&dentry->d_lock); diff --git a/include/linux/fsnotify.h b/include/linux/fsnotify.h index b10bcdeaef76..2a53f10712b3 100644 --- a/include/linux/fsnotify.h +++ b/include/linux/fsnotify.h @@ -17,7 +17,6 @@ /* * fsnotify_d_instantiate - instantiate a dentry for inode - * Called with dcache_lock held. */ static inline void fsnotify_d_instantiate(struct dentry *dentry, struct inode *inode) @@ -62,7 +61,6 @@ static inline int fsnotify_perm(struct file *file, int mask) /* * fsnotify_d_move - dentry has been moved - * Called with dcache_lock and dentry->d_lock held. */ static inline void fsnotify_d_move(struct dentry *dentry) { diff --git a/include/linux/fsnotify_backend.h b/include/linux/fsnotify_backend.h index 7380763595d3..69ad89b50489 100644 --- a/include/linux/fsnotify_backend.h +++ b/include/linux/fsnotify_backend.h @@ -329,9 +329,15 @@ static inline void __fsnotify_update_dcache_flags(struct dentry *dentry) { struct dentry *parent; - assert_spin_locked(&dcache_lock); assert_spin_locked(&dentry->d_lock); + /* + * Serialisation of setting PARENT_WATCHED on the dentries is provided + * by d_lock. If inotify_inode_watched changes after we have taken + * d_lock, the following __fsnotify_update_child_dentry_flags call will + * find our entry, so it will spin until we complete here, and update + * us with the new state. + */ parent = dentry->d_parent; if (parent->d_inode && fsnotify_inode_watches_children(parent->d_inode)) dentry->d_flags |= DCACHE_FSNOTIFY_PARENT_WATCHED; @@ -341,15 +347,12 @@ static inline void __fsnotify_update_dcache_flags(struct dentry *dentry) /* * fsnotify_d_instantiate - instantiate a dentry for inode - * Called with dcache_lock held. */ static inline void __fsnotify_d_instantiate(struct dentry *dentry, struct inode *inode) { if (!inode) return; - assert_spin_locked(&dcache_lock); - spin_lock(&dentry->d_lock); __fsnotify_update_dcache_flags(dentry); spin_unlock(&dentry->d_lock); diff --git a/include/linux/namei.h b/include/linux/namei.h index 05b441d93642..aec730b53935 100644 --- a/include/linux/namei.h +++ b/include/linux/namei.h @@ -41,7 +41,6 @@ enum {LAST_NORM, LAST_ROOT, LAST_DOT, LAST_DOTDOT, LAST_BIND}; * - require a directory * - ending slashes ok even for nonexistent files * - internal "there are more path components" flag - * - locked when lookup done with dcache_lock held * - dentry cache is untrusted; force a real lookup */ #define LOOKUP_FOLLOW 1 diff --git a/kernel/cgroup.c b/kernel/cgroup.c index 7b4705b51d4a..1864cb6a6a59 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -876,7 +876,6 @@ static void cgroup_clear_directory(struct dentry *dentry) struct list_head *node; BUG_ON(!mutex_is_locked(&dentry->d_inode->i_mutex)); - spin_lock(&dcache_lock); spin_lock(&dentry->d_lock); node = dentry->d_subdirs.next; while (node != &dentry->d_subdirs) { @@ -891,18 +890,15 @@ static void cgroup_clear_directory(struct dentry *dentry) dget_locked_dlock(d); spin_unlock(&d->d_lock); spin_unlock(&dentry->d_lock); - spin_unlock(&dcache_lock); d_delete(d); simple_unlink(dentry->d_inode, d); dput(d); - spin_lock(&dcache_lock); spin_lock(&dentry->d_lock); } else spin_unlock(&d->d_lock); node = dentry->d_subdirs.next; } spin_unlock(&dentry->d_lock); - spin_unlock(&dcache_lock); } /* @@ -914,14 +910,12 @@ static void cgroup_d_remove_dir(struct dentry *dentry) cgroup_clear_directory(dentry); - spin_lock(&dcache_lock); parent = dentry->d_parent; spin_lock(&parent->d_lock); spin_lock(&dentry->d_lock); list_del_init(&dentry->d_u.d_child); spin_unlock(&dentry->d_lock); spin_unlock(&parent->d_lock); - spin_unlock(&dcache_lock); remove_dir(dentry); } diff --git a/mm/filemap.c b/mm/filemap.c index 6b9aee20f242..ca389394fa2a 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -102,9 +102,6 @@ * ->inode_lock (zap_pte_range->set_page_dirty) * ->private_lock (zap_pte_range->__set_page_dirty_buffers) * - * ->task->proc_lock - * ->dcache_lock (proc_pid_lookup) - * * (code doesn't rely on that order, so you could switch it around) * ->tasklist_lock (memory_failure, collect_procs_ao) * ->i_mmap_lock diff --git a/security/selinux/selinuxfs.c b/security/selinux/selinuxfs.c index 017ec096446e..2285d693f296 100644 --- a/security/selinux/selinuxfs.c +++ b/security/selinux/selinuxfs.c @@ -1145,7 +1145,6 @@ static void sel_remove_entries(struct dentry *de) { struct list_head *node; - spin_lock(&dcache_lock); spin_lock(&de->d_lock); node = de->d_subdirs.next; while (node != &de->d_subdirs) { @@ -1158,11 +1157,9 @@ static void sel_remove_entries(struct dentry *de) dget_locked_dlock(d); spin_unlock(&de->d_lock); spin_unlock(&d->d_lock); - spin_unlock(&dcache_lock); d_delete(d); simple_unlink(de->d_inode, d); dput(d); - spin_lock(&dcache_lock); spin_lock(&de->d_lock); } else spin_unlock(&d->d_lock); @@ -1170,7 +1167,6 @@ static void sel_remove_entries(struct dentry *de) } spin_unlock(&de->d_lock); - spin_unlock(&dcache_lock); } #define BOOL_DIR_NAME "booleans" -- cgit v1.2.3