diff options
Diffstat (limited to 'fs/autofs4')
-rw-r--r-- | fs/autofs4/autofs_i.h | 11 | ||||
-rw-r--r-- | fs/autofs4/expire.c | 127 | ||||
-rw-r--r-- | fs/autofs4/root.c | 18 |
3 files changed, 87 insertions, 69 deletions
diff --git a/fs/autofs4/autofs_i.h b/fs/autofs4/autofs_i.h index 3912dcf..9d2ae9b 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 ee64020..968c143 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 7922509..7a9ed6b 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); |