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-rw-r--r--fs/autofs4/autofs_i.h21
-rw-r--r--fs/autofs4/expire.c141
-rw-r--r--fs/autofs4/inode.c2
-rw-r--r--fs/autofs4/root.c91
-rw-r--r--fs/autofs4/waitq.c23
5 files changed, 164 insertions, 114 deletions
diff --git a/fs/autofs4/autofs_i.h b/fs/autofs4/autofs_i.h
index 3d283abf67d..0fffe1c24ce 100644
--- a/fs/autofs4/autofs_i.h
+++ b/fs/autofs4/autofs_i.h
@@ -16,6 +16,7 @@
#include <linux/auto_fs4.h>
#include <linux/auto_dev-ioctl.h>
#include <linux/mutex.h>
+#include <linux/spinlock.h>
#include <linux/list.h>
/* 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
@@ -254,17 +257,15 @@ static inline int simple_positive(struct dentry *dentry)
return dentry->d_inode && !d_unhashed(dentry);
}
-static inline int __simple_empty(struct dentry *dentry)
+static inline void __autofs4_add_expiring(struct dentry *dentry)
{
- struct dentry *child;
- int ret = 0;
-
- list_for_each_entry(child, &dentry->d_subdirs, d_u.d_child)
- if (simple_positive(child))
- goto out;
- ret = 1;
-out:
- return ret;
+ 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)
diff --git a/fs/autofs4/expire.c b/fs/autofs4/expire.c
index a796c9417fb..cc1d0136590 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(&autofs4_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(&autofs4_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(&autofs4_lock);
+
+ dput(prev);
+
+ return ret;
}
/*
@@ -158,18 +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)) {
- /* Negative dentry - give up */
- if (!simple_positive(p))
- 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(p);
- spin_unlock(&dcache_lock);
-
/*
* Is someone visiting anywhere in the subtree ?
* If there's no mount we need to check the usage
@@ -198,16 +231,13 @@ static int autofs4_tree_busy(struct vfsmount *mnt,
else
ino_count++;
- if (atomic_read(&p->d_count) > ino_count) {
+ if (p->d_count > ino_count) {
top_ino->last_used = jiffies;
dput(p);
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))
@@ -226,32 +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)) {
- /* Negative dentry - give up */
- if (!simple_positive(p))
- 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(p);
- 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;
}
@@ -276,7 +295,9 @@ struct dentry *autofs4_expire_direct(struct super_block *sb,
struct autofs_info *ino = autofs4_dentry_ino(root);
if (d_mountpoint(root)) {
ino->flags |= AUTOFS_INF_MOUNTPOINT;
- root->d_mounted--;
+ spin_lock(&root->d_lock);
+ root->d_flags &= ~DCACHE_MOUNTED;
+ spin_unlock(&root->d_lock);
}
ino->flags |= AUTOFS_INF_EXPIRING;
init_completion(&ino->expire_complete);
@@ -302,8 +323,8 @@ 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;
@@ -315,23 +336,8 @@ 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 */
- if (!simple_positive(dentry)) {
- next = next->next;
- continue;
- }
-
- dentry = dget(dentry);
- spin_unlock(&dcache_lock);
-
+ dentry = NULL;
+ while ((dentry = get_next_positive_dentry(dentry, root))) {
spin_lock(&sbi->fs_lock);
ino = autofs4_dentry_ino(dentry);
@@ -347,7 +353,7 @@ struct dentry *autofs4_expire_indirect(struct super_block *sb,
/* Path walk currently on this dentry? */
ino_count = atomic_read(&ino->count) + 2;
- if (atomic_read(&dentry->d_count) > ino_count)
+ if (dentry->d_count > ino_count)
goto next;
/* Can we umount this guy */
@@ -369,7 +375,7 @@ struct dentry *autofs4_expire_indirect(struct super_block *sb,
if (!exp_leaves) {
/* Path walk currently on this dentry? */
ino_count = atomic_read(&ino->count) + 1;
- if (atomic_read(&dentry->d_count) > ino_count)
+ if (dentry->d_count > ino_count)
goto next;
if (!autofs4_tree_busy(mnt, dentry, timeout, do_now)) {
@@ -383,7 +389,7 @@ struct dentry *autofs4_expire_indirect(struct super_block *sb,
} else {
/* Path walk currently on this dentry? */
ino_count = atomic_read(&ino->count) + 1;
- if (atomic_read(&dentry->d_count) > ino_count)
+ if (dentry->d_count > ino_count)
goto next;
expired = autofs4_check_leaves(mnt, dentry, timeout, do_now);
@@ -394,11 +400,7 @@ 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:
@@ -408,9 +410,13 @@ 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(&dcache_lock);
+ spin_unlock(&expired->d_lock);
+ spin_unlock(&expired->d_parent->d_lock);
+ spin_unlock(&autofs4_lock);
return expired;
}
@@ -499,7 +505,14 @@ int autofs4_do_expire_multi(struct super_block *sb, struct vfsmount *mnt,
spin_lock(&sbi->fs_lock);
if (ino->flags & AUTOFS_INF_MOUNTPOINT) {
- sb->s_root->d_mounted++;
+ spin_lock(&sb->s_root->d_lock);
+ /*
+ * If we haven't been expired away, then reset
+ * mounted status.
+ */
+ if (mnt->mnt_parent != mnt)
+ sb->s_root->d_flags |= DCACHE_MOUNTED;
+ spin_unlock(&sb->s_root->d_lock);
ino->flags &= ~AUTOFS_INF_MOUNTPOINT;
}
ino->flags &= ~AUTOFS_INF_EXPIRING;
diff --git a/fs/autofs4/inode.c b/fs/autofs4/inode.c
index ac87e49fa70..a7bdb9dcac8 100644
--- a/fs/autofs4/inode.c
+++ b/fs/autofs4/inode.c
@@ -309,7 +309,7 @@ int autofs4_fill_super(struct super_block *s, void *data, int silent)
goto fail_iput;
pipe = NULL;
- root->d_op = &autofs4_sb_dentry_operations;
+ d_set_d_op(root, &autofs4_sb_dentry_operations);
root->d_fsdata = ino;
/* Can this call block? */
diff --git a/fs/autofs4/root.c b/fs/autofs4/root.c
index d34896cfb19..651e4ef563b 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 *);
@@ -142,12 +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(&dcache_lock);
+ spin_unlock(&dentry->d_lock);
+ spin_unlock(&autofs4_lock);
return -ENOENT;
}
- spin_unlock(&dcache_lock);
+ spin_unlock(&dentry->d_lock);
+ spin_unlock(&autofs4_lock);
out:
return dcache_dir_open(inode, file);
@@ -252,9 +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(&dcache_lock);
+ spin_unlock(&dentry->d_lock);
+ spin_unlock(&autofs4_lock);
spin_unlock(&sbi->fs_lock);
goto follow;
}
@@ -266,7 +273,8 @@ 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(&dcache_lock);
+ spin_unlock(&dentry->d_lock);
+ spin_unlock(&autofs4_lock);
spin_unlock(&sbi->fs_lock);
status = try_to_fill_dentry(dentry, nd->flags);
@@ -275,7 +283,8 @@ static void *autofs4_follow_link(struct dentry *dentry, struct nameidata *nd)
goto follow;
}
- spin_unlock(&dcache_lock);
+ spin_unlock(&dentry->d_lock);
+ spin_unlock(&autofs4_lock);
spin_unlock(&sbi->fs_lock);
follow:
/*
@@ -306,12 +315,19 @@ out_error:
*/
static int autofs4_revalidate(struct dentry *dentry, struct nameidata *nd)
{
- struct inode *dir = dentry->d_parent->d_inode;
- struct autofs_sb_info *sbi = autofs4_sbi(dir->i_sb);
- int oz_mode = autofs4_oz_mode(sbi);
+ struct inode *dir;
+ struct autofs_sb_info *sbi;
+ int oz_mode;
int flags = nd ? nd->flags : 0;
int status = 1;
+ if (flags & LOOKUP_RCU)
+ return -ECHILD;
+
+ dir = dentry->d_parent->d_inode;
+ sbi = autofs4_sbi(dir->i_sb);
+ oz_mode = autofs4_oz_mode(sbi);
+
/* Pending dentry */
spin_lock(&sbi->fs_lock);
if (autofs4_ispending(dentry)) {
@@ -346,12 +362,14 @@ 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(&dcache_lock);
+ spin_unlock(&dentry->d_lock);
+ spin_unlock(&autofs4_lock);
/* The daemon never causes a mount to trigger */
if (oz_mode)
@@ -367,7 +385,8 @@ static int autofs4_revalidate(struct dentry *dentry, struct nameidata *nd)
return status;
}
- spin_unlock(&dcache_lock);
+ spin_unlock(&dentry->d_lock);
+ spin_unlock(&autofs4_lock);
return 1;
}
@@ -422,7 +441,7 @@ 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) {
@@ -436,7 +455,7 @@ static struct dentry *autofs4_lookup_active(struct dentry *dentry)
spin_lock(&active->d_lock);
/* Already gone? */
- if (atomic_read(&active->d_count) == 0)
+ if (active->d_count == 0)
goto next;
qstr = &active->d_name;
@@ -452,17 +471,17 @@ static struct dentry *autofs4_lookup_active(struct dentry *dentry)
goto next;
if (d_unhashed(active)) {
- dget(active);
+ 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;
}
@@ -477,7 +496,7 @@ 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) {
@@ -507,17 +526,17 @@ static struct dentry *autofs4_lookup_expiring(struct dentry *dentry)
goto next;
if (d_unhashed(expiring)) {
- dget(expiring);
+ 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;
}
@@ -559,7 +578,7 @@ static struct dentry *autofs4_lookup(struct inode *dir, struct dentry *dentry, s
* we check for the hashed dentry and return the newly
* hashed dentry.
*/
- dentry->d_op = &autofs4_root_dentry_operations;
+ d_set_d_op(dentry, &autofs4_root_dentry_operations);
/*
* And we need to ensure that the same dentry is used for
@@ -698,9 +717,9 @@ static int autofs4_dir_symlink(struct inode *dir,
d_add(dentry, inode);
if (dir == dir->i_sb->s_root->d_inode)
- dentry->d_op = &autofs4_root_dentry_operations;
+ d_set_d_op(dentry, &autofs4_root_dentry_operations);
else
- dentry->d_op = &autofs4_dentry_operations;
+ d_set_d_op(dentry, &autofs4_dentry_operations);
dentry->d_fsdata = ino;
ino->dentry = dget(dentry);
@@ -753,12 +772,12 @@ 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;
}
@@ -775,16 +794,20 @@ 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(&dcache_lock);
+ spin_unlock(&dentry->d_lock);
+ spin_unlock(&sbi->lookup_lock);
+ spin_unlock(&autofs4_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);
+ spin_unlock(&autofs4_lock);
if (atomic_dec_and_test(&ino->count)) {
p_ino = autofs4_dentry_ino(dentry->d_parent);
@@ -829,9 +852,9 @@ static int autofs4_dir_mkdir(struct inode *dir, struct dentry *dentry, int mode)
d_add(dentry, inode);
if (dir == dir->i_sb->s_root->d_inode)
- dentry->d_op = &autofs4_root_dentry_operations;
+ d_set_d_op(dentry, &autofs4_root_dentry_operations);
else
- dentry->d_op = &autofs4_dentry_operations;
+ d_set_d_op(dentry, &autofs4_dentry_operations);
dentry->d_fsdata = ino;
ino->dentry = dget(dentry);
diff --git a/fs/autofs4/waitq.c b/fs/autofs4/waitq.c
index 2341375386f..c5f8459c905 100644
--- a/fs/autofs4/waitq.c
+++ b/fs/autofs4/waitq.c
@@ -186,16 +186,26 @@ static int autofs4_getpath(struct autofs_sb_info *sbi,
{
struct dentry *root = sbi->sb->s_root;
struct dentry *tmp;
- char *buf = *name;
+ char *buf;
char *p;
- int len = 0;
+ int len;
+ unsigned seq;
- spin_lock(&dcache_lock);
+rename_retry:
+ buf = *name;
+ len = 0;
+
+ seq = read_seqbegin(&rename_lock);
+ rcu_read_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;
return 0;
}
@@ -208,7 +218,10 @@ static int autofs4_getpath(struct autofs_sb_info *sbi,
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;
return len;
}
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-27 14:33:38 +0000