[patch 14/33] fs: dcache remove dcache_lock

From: npiggin
Date: Fri Sep 04 2009 - 03:01:49 EST


dcache_lock no longer protects anything (I hope). remove it.

This breaks a lot of the tree where I haven't thought about the problem,
but it simplifies the dcache.c code quite a bit (and it's also probably
a good thing to break unconverted code). So I include this here before
making further changes to the locking.

---
Documentation/filesystems/Locking | 2
arch/powerpc/platforms/cell/spufs/inode.c | 5 -
drivers/infiniband/hw/ipath/ipath_fs.c | 6 -
drivers/staging/pohmelfs/path_entry.c | 2
drivers/usb/core/inode.c | 3
fs/affs/amigaffs.c | 2
fs/autofs4/expire.c | 11 --
fs/autofs4/inode.c | 6 -
fs/autofs4/root.c | 20 ----
fs/autofs4/waitq.c | 3
fs/coda/cache.c | 2
fs/configfs/configfs_internal.h | 2
fs/configfs/inode.c | 6 -
fs/dcache.c | 131 ++++--------------------------
fs/exportfs/expfs.c | 4
fs/namei.c | 5 -
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/notify/inotify/inotify.c | 4
fs/ocfs2/dcache.c | 2
fs/seq_file.c | 2
fs/smbfs/cache.c | 4
fs/sysfs/dir.c | 3
include/linux/dcache.h | 17 +--
include/linux/fsnotify_backend.h | 5 -
kernel/cgroup.c | 6 -
net/sunrpc/rpc_pipe.c | 11 +-
security/selinux/selinuxfs.c | 4
security/tomoyo/realpath.c | 2
33 files changed, 37 insertions(+), 250 deletions(-)

Index: linux-2.6/fs/dcache.c
===================================================================
--- linux-2.6.orig/fs/dcache.c
+++ linux-2.6/fs/dcache.c
@@ -50,11 +50,10 @@
* - d_subdirs and children's d_child
*
* 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
*/
int sysctl_vfs_cache_pressure __read_mostly = 100;
EXPORT_SYMBOL_GPL(sysctl_vfs_cache_pressure);
@@ -62,12 +61,10 @@ EXPORT_SYMBOL_GPL(sysctl_vfs_cache_press
__cacheline_aligned_in_smp DEFINE_SPINLOCK(dcache_inode_lock);
__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(dcache_inode_lock);
EXPORT_SYMBOL(dcache_hash_lock);
-EXPORT_SYMBOL(dcache_lock);

static struct kmem_cache *dentry_cache __read_mostly;

@@ -109,7 +106,7 @@ static void d_callback(struct rcu_head *
}

/*
- * no dcache_lock, please.
+ * no locks, please.
*/
static void d_free(struct dentry *dentry)
{
@@ -131,7 +128,6 @@ 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) {
@@ -139,7 +135,6 @@ static void dentry_iput(struct 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)
@@ -149,7 +144,6 @@ static void dentry_iput(struct dentry *
} else {
spin_unlock(&dentry->d_lock);
spin_unlock(&dcache_inode_lock);
- spin_unlock(&dcache_lock);
}
}

@@ -215,13 +209,12 @@ static void dentry_lru_del_init(struct d
*
* 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
+ * 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)
__releases(dentry->d_lock)
__releases(dcache_inode_lock)
- __releases(dcache_lock)
{
struct dentry *parent;

@@ -278,21 +271,10 @@ repeat:
might_sleep();
spin_lock(&dentry->d_lock);
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;
}
parent = dentry->d_parent;
if (parent) {
@@ -306,7 +288,6 @@ drop2:
dentry->d_count--;
if (dentry->d_count) {
spin_unlock(&dentry->d_lock);
- spin_unlock(&dcache_lock);
return;
}

@@ -328,7 +309,6 @@ drop2:
if (parent)
spin_unlock(&parent->d_lock);
spin_unlock(&dcache_inode_lock);
- spin_unlock(&dcache_lock);
return;

unhash_it:
@@ -358,11 +338,9 @@ 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;
}
/*
@@ -371,9 +349,7 @@ 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);
}

/*
@@ -390,14 +366,12 @@ 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;
}

@@ -501,11 +475,9 @@ struct dentry * d_find_alias(struct inod
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;
}
@@ -518,7 +490,6 @@ 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);
@@ -527,14 +498,12 @@ 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);
}

/*
@@ -547,20 +516,16 @@ restart:
*/
static void prune_one_dentry(struct dentry * dentry)
__releases(dentry->d_lock)
- __releases(dcache_lock)
- __acquires(dcache_lock)
{
__d_drop(dentry);
dentry = d_kill(dentry);

/*
- * Prune ancestors. Locking is simpler than in dput(),
- * because dcache_lock needs to be taken anyway.
+ * Prune ancestors.
*/
while (dentry) {
struct dentry *parent = NULL;

- spin_lock(&dcache_lock);
spin_lock(&dcache_inode_lock);
again:
spin_lock(&dentry->d_lock);
@@ -577,7 +542,6 @@ again:
spin_unlock(&parent->d_lock);
spin_unlock(&dentry->d_lock);
spin_unlock(&dcache_inode_lock);
- spin_unlock(&dcache_lock);
return;
}

@@ -646,7 +610,6 @@ restart:
}
spin_unlock(&dcache_lru_lock);

- spin_lock(&dcache_lock);
spin_lock(&dcache_inode_lock);
again:
spin_lock(&dcache_lru_lock); /* lru_lock also protects tmp list */
@@ -677,14 +640,13 @@ again1:
}
__dentry_lru_del_init(dentry);
spin_unlock(&dcache_lru_lock);
+
prune_one_dentry(dentry);
- /* dcache_lock and dentry->d_lock dropped */
- spin_lock(&dcache_lock);
+ /* dentry->d_lock dropped */
spin_lock(&dcache_inode_lock);
spin_lock(&dcache_lru_lock);
}
spin_unlock(&dcache_inode_lock);
- spin_unlock(&dcache_lock);

if (count == NULL && !list_empty(&sb->s_dentry_lru))
goto restart;
@@ -714,7 +676,6 @@ static void prune_dcache(int count)

if (unused == 0 || count == 0)
return;
- spin_lock(&dcache_lock);
restart:
if (count >= unused)
prune_ratio = 1;
@@ -750,11 +711,9 @@ restart:
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);
}
@@ -770,7 +729,6 @@ restart:
}
}
spin_unlock(&sb_lock);
- spin_unlock(&dcache_lock);
}

/**
@@ -799,12 +757,10 @@ static void shrink_dcache_for_umount_sub
BUG_ON(!IS_ROOT(dentry));

/* detach this root from the system */
- spin_lock(&dcache_lock);
spin_lock(&dentry->d_lock);
dentry_lru_del_init(dentry);
__d_drop(dentry);
spin_unlock(&dentry->d_lock);
- spin_unlock(&dcache_lock);

for (;;) {
/* descend to the first leaf in the current subtree */
@@ -813,7 +769,6 @@ static void shrink_dcache_for_umount_sub

/* 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) {
@@ -823,7 +778,6 @@ static void shrink_dcache_for_umount_sub
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,
@@ -894,8 +848,7 @@ out:

/*
* 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
@@ -946,7 +899,6 @@ 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);
@@ -993,7 +945,6 @@ resume:
// d_unlinked(this_parent) || XXX
read_seqretry(&rename_lock, seq)) {
spin_unlock(&this_parent->d_lock);
- spin_unlock(&dcache_lock);
rcu_read_unlock();
goto rename_retry;
}
@@ -1002,12 +953,10 @@ 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;
@@ -1038,7 +987,6 @@ 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;
@@ -1101,7 +1049,6 @@ resume:
// d_unlinked(this_parent) || XXX
read_seqretry(&rename_lock, seq)) {
spin_unlock(&this_parent->d_lock);
- spin_unlock(&dcache_lock);
rcu_read_unlock();
goto rename_retry;
}
@@ -1111,7 +1058,6 @@ resume:
}
out:
spin_unlock(&this_parent->d_lock);
- spin_unlock(&dcache_lock);
if (read_seqretry(&rename_lock, seq))
goto rename_retry;
return found;
@@ -1211,7 +1157,6 @@ struct dentry *d_alloc(struct dentry * p
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);
@@ -1219,7 +1164,6 @@ struct dentry *d_alloc(struct dentry * p
list_add(&dentry->d_u.d_child, &parent->d_subdirs);
spin_unlock(&dentry->d_lock);
spin_unlock(&parent->d_lock);
- spin_unlock(&dcache_lock);
}

atomic_inc(&dentry_stat.nr_dentry);
@@ -1237,7 +1181,6 @@ struct dentry *d_alloc_name(struct dentr
return d_alloc(parent, &q);
}

-/* the caller must hold dcache_lock */
static void __d_instantiate(struct dentry *dentry, struct inode *inode)
{
if (inode)
@@ -1264,11 +1207,9 @@ static void __d_instantiate(struct dentr
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);
}

@@ -1326,11 +1267,9 @@ struct dentry *d_instantiate_unique(stru

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);
@@ -1418,12 +1357,10 @@ struct dentry *d_obtain_alias(struct ino
}
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;
}
@@ -1439,7 +1376,6 @@ struct dentry *d_obtain_alias(struct ino
spin_unlock(&tmp->d_lock);
spin_unlock(&dcache_inode_lock);

- spin_unlock(&dcache_lock);
return tmp;

out_iput:
@@ -1469,22 +1405,19 @@ struct dentry *d_splice_alias(struct ino
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_rehash(dentry);
d_move(new, dentry);
iput(inode);
} else {
- /* already taking dcache_lock, so d_add() by hand */
+ /* already taken dcache_inode_lock, 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);
}
@@ -1556,12 +1489,10 @@ struct dentry *d_add_ci(struct dentry *d
* 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;
}
@@ -1573,7 +1504,6 @@ struct dentry *d_add_ci(struct dentry *d
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);
@@ -1595,7 +1525,7 @@ err_out:
* is returned. The caller must use dput to free the entry when it has
* finished using it. %NULL is returned on failure.
*
- * __d_lookup is dcache_lock free. The hash list is protected using RCU.
+ * __d_lookup is global lock free. The hash list is protected using RCU.
* Memory barriers are used while updating and doing lockless traversal.
* To avoid races with d_move while rename is happening, d_lock is used.
*
@@ -1607,7 +1537,7 @@ err_out:
*
* The dentry unused LRU is not updated even if lookup finds the required dentry
* in there. It is updated in places such as prune_dcache, shrink_dcache_sb,
- * select_parent and __dget_locked. This laziness saves lookup from dcache_lock
+ * select_parent and __dget_locked. This laziness saves lookup from LRU lock
* acquisition.
*
* d_lookup() is protected against the concurrent renames in some unrelated
@@ -1737,25 +1667,22 @@ int d_validate(struct dentry *dentry, st
if (dentry->d_parent != dparent)
goto out;

- spin_lock(&dcache_lock);
spin_lock(&dentry->d_lock);
spin_lock(&dcache_hash_lock);
base = d_hash(dparent, dentry->d_name.hash);
hlist_for_each(lhp,base) {
/* hlist_for_each_entry_rcu() not required for d_hash list
- * as it is parsed under dcache_lock
+ * as it is parsed under dcache_hash_lock
*/
if (dentry == hlist_entry(lhp, struct dentry, d_hash)) {
spin_unlock(&dcache_hash_lock);
__dget_locked_dlock(dentry);
spin_unlock(&dentry->d_lock);
- spin_unlock(&dcache_lock);
return 1;
}
}
spin_unlock(&dcache_hash_lock);
spin_unlock(&dentry->d_lock);
- spin_unlock(&dcache_lock);
out:
return 0;
}
@@ -1787,7 +1714,6 @@ 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);
@@ -1802,7 +1728,6 @@ void d_delete(struct dentry * dentry)

spin_unlock(&dentry->d_lock);
spin_unlock(&dcache_inode_lock);
- spin_unlock(&dcache_lock);

fsnotify_nameremove(dentry, isdir);
}
@@ -1828,13 +1753,11 @@ static void _d_rehash(struct dentry * en

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);
}

/*
@@ -1988,9 +1911,7 @@ static void d_move_locked(struct dentry

void d_move(struct dentry * dentry, struct dentry * target)
{
- spin_lock(&dcache_lock);
d_move_locked(dentry, target);
- spin_unlock(&dcache_lock);
}

/**
@@ -2016,13 +1937,12 @@ struct dentry *d_ancestor(struct dentry
* 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
*
* 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)
{
struct mutex *m1 = NULL, *m2 = NULL;
struct dentry *ret;
@@ -2049,7 +1969,6 @@ out_unalias:
ret = alias;
out_err:
spin_unlock(&dcache_inode_lock);
- spin_unlock(&dcache_lock);
if (m2)
mutex_unlock(m2);
if (m1)
@@ -2113,7 +2032,6 @@ struct dentry *d_materialise_unique(stru

BUG_ON(!d_unhashed(dentry));

- spin_lock(&dcache_lock);
spin_lock(&dcache_inode_lock);

if (!inode) {
@@ -2160,7 +2078,6 @@ 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);
@@ -2172,7 +2089,6 @@ out_nolock:

shouldnt_be_hashed:
spin_unlock(&dcache_inode_lock);
- spin_unlock(&dcache_lock);
BUG();
}

@@ -2204,8 +2120,7 @@ static int prepend_name(char **buffer, i
* Returns a pointer into the buffer or an error code if the
* path was too long.
*
- * "buflen" should be positive. Caller holds the dcache_lock and
- * path->dentry->d_lock.
+ * "buflen" should be positive. Caller holds the path->dentry->d_lock.
*
* If path is not reachable from the supplied root, then the value of
* root is changed (without modifying refcounts).
@@ -2310,14 +2225,12 @@ char *d_path(const struct path *path, ch

rename_retry:
seq = read_seqbegin(&rename_lock);
- spin_lock(&dcache_lock);
vfsmount_read_lock();
spin_lock(&path->dentry->d_lock);
tmp = root;
res = __d_path(path, &tmp, buf, buflen);
spin_unlock(&path->dentry->d_lock);
vfsmount_read_unlock();
- spin_unlock(&dcache_lock);
if (read_seqretry(&rename_lock, seq))
goto rename_retry;

@@ -2359,7 +2272,6 @@ rename_retry:
end = buf + buflen;
seq = read_seqbegin(&rename_lock);
rcu_read_lock(); /* protect parent */
- spin_lock(&dcache_lock);
spin_lock(&dentry->d_lock);
prepend(&end, &buflen, "\0", 1);
if (d_unlinked(dentry) &&
@@ -2384,7 +2296,6 @@ rename_retry:
}
out:
spin_unlock(&dentry->d_lock);
- spin_unlock(&dcache_lock);
rcu_read_unlock();
if (read_seqretry(&rename_lock, seq))
goto rename_retry;
@@ -2429,7 +2340,6 @@ SYSCALL_DEFINE2(getcwd, char __user *, b
read_unlock(&current->fs->lock);

error = -ENOENT;
- spin_lock(&dcache_lock);
vfsmount_read_lock();
spin_lock(&pwd.dentry->d_lock);
if (!d_unlinked(pwd.dentry)) {
@@ -2440,7 +2350,6 @@ SYSCALL_DEFINE2(getcwd, char __user *, b
cwd = __d_path(&pwd, &tmp, page, PAGE_SIZE);
spin_unlock(&pwd.dentry->d_lock);
vfsmount_read_unlock();
- spin_unlock(&dcache_lock);

error = PTR_ERR(cwd);
if (IS_ERR(cwd))
@@ -2456,7 +2365,6 @@ SYSCALL_DEFINE2(getcwd, char __user *, b
} else {
spin_unlock(&pwd.dentry->d_lock);
vfsmount_read_unlock();
- spin_unlock(&dcache_lock);
}

out:
@@ -2517,7 +2425,6 @@ 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;
@@ -2559,7 +2466,6 @@ resume:
// d_unlinked(this_parent) || XXX
read_seqretry(&rename_lock, seq)) {
spin_unlock(&this_parent->d_lock);
- spin_unlock(&dcache_lock);
rcu_read_unlock();
goto rename_retry;
}
@@ -2568,7 +2474,6 @@ resume:
goto resume;
}
spin_unlock(&this_parent->d_lock);
- spin_unlock(&dcache_lock);
if (read_seqretry(&rename_lock, seq))
goto rename_retry;
}
Index: linux-2.6/fs/namei.c
===================================================================
--- linux-2.6.orig/fs/namei.c
+++ linux-2.6/fs/namei.c
@@ -759,14 +759,11 @@ static __always_inline void follow_dotdo
nd->path.mnt == nd->root.mnt) {
break;
}
- spin_lock(&dcache_lock);
if (nd->path.dentry != nd->path.mnt->mnt_root) {
nd->path.dentry = dget(nd->path.dentry->d_parent);
- spin_unlock(&dcache_lock);
dput(old);
break;
}
- spin_unlock(&dcache_lock);
vfsmount_read_lock();
parent = nd->path.mnt->mnt_parent;
if (parent == nd->path.mnt) {
@@ -2159,12 +2156,10 @@ 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)
Index: linux-2.6/fs/seq_file.c
===================================================================
--- linux-2.6.orig/fs/seq_file.c
+++ linux-2.6/fs/seq_file.c
@@ -463,11 +463,9 @@ int seq_path_root(struct seq_file *m, st

rename_retry:
seq = read_seqbegin(&rename_lock);
- spin_lock(&dcache_lock);
vfsmount_read_lock();
p = __d_path(path, root, s, m->size - m->count);
vfsmount_read_unlock();
- spin_unlock(&dcache_lock);
if (read_seqretry(&rename_lock, seq))
goto rename_retry;

Index: linux-2.6/fs/sysfs/dir.c
===================================================================
--- linux-2.6.orig/fs/sysfs/dir.c
+++ linux-2.6/fs/sysfs/dir.c
@@ -547,7 +547,6 @@ static void sysfs_drop_dentry(struct sys
* dput to immediately free the dentry if it is not in use.
*/
repeat:
- spin_lock(&dcache_lock);
spin_lock(&dcache_inode_lock);
list_for_each_entry(dentry, &inode->i_dentry, d_alias) {
spin_lock(&dentry->d_lock);
@@ -559,12 +558,10 @@ repeat:
__d_drop(dentry);
spin_unlock(&dentry->d_lock);
spin_unlock(&dcache_inode_lock);
- spin_unlock(&dcache_lock);
dput(dentry);
goto repeat;
}
spin_unlock(&dcache_inode_lock);
- spin_unlock(&dcache_lock);

/* adjust nlink and update timestamp */
mutex_lock(&inode->i_mutex);
Index: linux-2.6/include/linux/dcache.h
===================================================================
--- linux-2.6.orig/include/linux/dcache.h
+++ linux-2.6/include/linux/dcache.h
@@ -150,13 +150,13 @@ struct dentry_operations {

/*
locking rules:
- big lock dcache_lock d_lock may block
-d_revalidate: no no no yes
-d_hash no no no yes
-d_compare: no yes yes no
-d_delete: no yes no no
-d_release: no no no yes
-d_iput: no no no yes
+ big lock d_lock may block
+d_revalidate: no no yes
+d_hash no no yes
+d_compare: no yes no
+d_delete: no no no
+d_release: no no yes
+d_iput: no no yes
*/

/* d_flags entries */
@@ -188,7 +188,6 @@ d_iput: no no no yes

extern spinlock_t dcache_inode_lock;
extern spinlock_t dcache_hash_lock;
-extern spinlock_t dcache_lock;
extern seqlock_t rename_lock;

/**
@@ -219,11 +218,9 @@ static inline void __d_drop(struct dentr

static inline 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);
}

static inline int dname_external(struct dentry *dentry)
Index: linux-2.6/fs/notify/inotify/inotify.c
===================================================================
--- linux-2.6.orig/fs/notify/inotify/inotify.c
+++ linux-2.6/fs/notify/inotify/inotify.c
@@ -185,7 +185,6 @@ static void set_dentry_child_flags(struc
{
struct dentry *alias;

- spin_lock(&dcache_lock);
spin_lock(&dcache_inode_lock);
list_for_each_entry(alias, &inode->i_dentry, d_alias) {
struct dentry *child;
@@ -205,7 +204,6 @@ static void set_dentry_child_flags(struc
spin_unlock(&alias->d_lock);
}
spin_unlock(&dcache_inode_lock);
- spin_unlock(&dcache_lock);
}

/*
@@ -273,6 +271,7 @@ void inotify_d_instantiate(struct dentry
if (!inode)
return;

+ /* XXX: need parent lock in place of dcache_lock? */
spin_lock(&entry->d_lock);
parent = entry->d_parent;
if (parent->d_inode && inotify_inode_watched(parent->d_inode))
@@ -287,6 +286,7 @@ void inotify_d_move(struct dentry *entry
{
struct dentry *parent;

+ /* XXX: need parent lock in place of dcache_lock? */
parent = entry->d_parent;
if (inotify_inode_watched(parent->d_inode))
entry->d_flags |= DCACHE_INOTIFY_PARENT_WATCHED;
Index: linux-2.6/fs/exportfs/expfs.c
===================================================================
--- linux-2.6.orig/fs/exportfs/expfs.c
+++ linux-2.6/fs/exportfs/expfs.c
@@ -47,24 +47,20 @@ find_acceptable_alias(struct dentry *res
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);
Index: linux-2.6/Documentation/filesystems/Locking
===================================================================
--- linux-2.6.orig/Documentation/filesystems/Locking
+++ linux-2.6/Documentation/filesystems/Locking
@@ -17,7 +17,7 @@ prototypes:
void (*d_iput)(struct dentry *, struct inode *);
char *(*d_dname)((struct dentry *dentry, char *buffer, int buflen);

-locking rules:
+locking rules: XXX: update these!!
none have BKL
dcache_lock rename_lock ->d_lock may block
d_revalidate: no no no yes
Index: linux-2.6/arch/powerpc/platforms/cell/spufs/inode.c
===================================================================
--- linux-2.6.orig/arch/powerpc/platforms/cell/spufs/inode.c
+++ linux-2.6/arch/powerpc/platforms/cell/spufs/inode.c
@@ -158,21 +158,18 @@ static void spufs_prune_dir(struct dentr

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);
Index: linux-2.6/drivers/infiniband/hw/ipath/ipath_fs.c
===================================================================
--- linux-2.6.orig/drivers/infiniband/hw/ipath/ipath_fs.c
+++ linux-2.6/drivers/infiniband/hw/ipath/ipath_fs.c
@@ -272,18 +272,14 @@ static int remove_file(struct dentry *pa
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:
Index: linux-2.6/drivers/usb/core/inode.c
===================================================================
--- linux-2.6.orig/drivers/usb/core/inode.c
+++ linux-2.6/drivers/usb/core/inode.c
@@ -348,18 +348,15 @@ static int usbfs_empty (struct dentry *d
{
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);
if (usbfs_positive(de)) {
spin_unlock(&dentry->d_lock);
- spin_unlock(&dcache_lock);
return 0;
}
}
spin_unlock(&dentry->d_lock);
- spin_unlock(&dcache_lock);

return 1;
}
Index: linux-2.6/fs/affs/amigaffs.c
===================================================================
--- linux-2.6.orig/fs/affs/amigaffs.c
+++ linux-2.6/fs/affs/amigaffs.c
@@ -128,7 +128,6 @@ affs_fix_dcache(struct dentry *dentry, u
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, u
next = next->next;
}
spin_unlock(&dcache_inode_lock);
- spin_unlock(&dcache_lock);
}


Index: linux-2.6/fs/autofs4/expire.c
===================================================================
--- linux-2.6.orig/fs/autofs4/expire.c
+++ linux-2.6/fs/autofs4/expire.c
@@ -105,7 +105,6 @@ static struct dentry *get_next_positive_
struct list_head *next;
struct dentry *ret;

- spin_lock(&dcache_lock);
spin_lock(&p->d_lock);
again:
next = p->d_subdirs.next;
@@ -123,9 +122,7 @@ again:
dget_dlock(p);
spin_unlock(&p->d_lock);
parent = dget_parent(p);
- spin_unlock(&dcache_lock);
dput(p);
- spin_lock(&dcache_lock);
spin_lock(&parent->d_lock);
} else
spin_unlock(&p->d_lock);
@@ -147,8 +144,6 @@ again:
dget_dlock(ret);
spin_unlock(&ret->d_lock);

- spin_unlock(&dcache_lock);
-
return ret;
}

@@ -338,7 +333,6 @@ struct dentry *autofs4_expire_indirect(s
now = jiffies;
timeout = sbi->exp_timeout;

- spin_lock(&dcache_lock);
spin_lock(&root->d_lock);
next = root->d_subdirs.next;

@@ -355,7 +349,6 @@ struct dentry *autofs4_expire_indirect(s

dentry = dget(dentry);
spin_unlock(&root->d_lock);
- spin_unlock(&dcache_lock);

spin_lock(&sbi->fs_lock);
ino = autofs4_dentry_ino(dentry);
@@ -420,12 +413,10 @@ struct dentry *autofs4_expire_indirect(s
next:
spin_unlock(&sbi->fs_lock);
dput(dentry);
- spin_lock(&dcache_lock);
spin_lock(&root->d_lock);
next = next->next;
}
spin_unlock(&root->d_lock);
- spin_unlock(&dcache_lock);
return NULL;

found:
@@ -435,11 +426,9 @@ found:
ino->flags |= AUTOFS_INF_EXPIRING;
init_completion(&ino->expire_complete);
spin_unlock(&sbi->fs_lock);
- spin_lock(&dcache_lock);
spin_lock(&expired->d_parent->d_lock);
list_move(&expired->d_parent->d_subdirs, &expired->d_u.d_child);
spin_unlock(&expired->d_parent->d_lock);
- spin_unlock(&dcache_lock);
return expired;
}

Index: linux-2.6/fs/autofs4/inode.c
===================================================================
--- linux-2.6.orig/fs/autofs4/inode.c
+++ linux-2.6/fs/autofs4/inode.c
@@ -109,7 +109,6 @@ static void autofs4_force_release(struct
if (!sbi->sb->s_root)
return;

- spin_lock(&dcache_lock);
repeat:
spin_lock(&this_parent->d_lock);
next = this_parent->d_subdirs.next;
@@ -130,13 +129,11 @@ resume:

next = next->next;
spin_unlock(&this_parent->d_lock);
- spin_unlock(&dcache_lock);

DPRINTK("dentry %p %.*s",
dentry, (int)dentry->d_name.len, dentry->d_name.name);

dput(dentry);
- spin_lock(&dcache_lock);
}

if (this_parent != sbi->sb->s_root) {
@@ -145,15 +142,12 @@ resume:
next = this_parent->d_u.d_child.next;
spin_unlock(&this_parent->d_lock);
this_parent = this_parent->d_parent;
- spin_unlock(&dcache_lock);
DPRINTK("parent dentry %p %.*s",
dentry, (int)dentry->d_name.len, dentry->d_name.name);
dput(dentry);
- spin_lock(&dcache_lock);
spin_lock(&this_parent->d_lock);
goto resume;
}
- spin_unlock(&dcache_lock);
spin_unlock(&this_parent->d_lock);
}

Index: linux-2.6/fs/autofs4/root.c
===================================================================
--- linux-2.6.orig/fs/autofs4/root.c
+++ linux-2.6/fs/autofs4/root.c
@@ -92,15 +92,12 @@ static int autofs4_dir_open(struct inode
* autofs file system so just let the libfs routines handle
* it.
*/
- spin_lock(&dcache_lock);
spin_lock(&dentry->d_lock);
if (!d_mountpoint(dentry) && __simple_empty(dentry)) {
spin_unlock(&dentry->d_lock);
- spin_unlock(&dcache_lock);
return -ENOENT;
}
spin_unlock(&dentry->d_lock);
- spin_unlock(&dcache_lock);

out:
return dcache_dir_open(inode, file);
@@ -214,12 +211,10 @@ static void *autofs4_follow_link(struct
* multi-mount with no root mount offset. So don't try to
* mount it again.
*/
- spin_lock(&dcache_lock);
spin_lock(&dentry->d_lock);
if (dentry->d_flags & DCACHE_AUTOFS_PENDING ||
(!d_mountpoint(dentry) && __simple_empty(dentry))) {
spin_unlock(&dentry->d_lock);
- spin_unlock(&dcache_lock);

status = try_to_fill_dentry(dentry, 0);
if (status)
@@ -228,7 +223,6 @@ static void *autofs4_follow_link(struct
goto follow;
}
spin_unlock(&dentry->d_lock);
- spin_unlock(&dcache_lock);
follow:
/*
* If there is no root mount it must be an autofs
@@ -298,13 +292,11 @@ static int autofs4_revalidate(struct den
return 0;

/* Check for a non-mountpoint directory with no contents */
- spin_lock(&dcache_lock);
if (S_ISDIR(dentry->d_inode->i_mode) &&
!d_mountpoint(dentry) &&
__simple_empty(dentry)) {
DPRINTK("dentry=%p %.*s, emptydir",
dentry, dentry->d_name.len, dentry->d_name.name);
- spin_unlock(&dcache_lock);

/* The daemon never causes a mount to trigger */
if (oz_mode)
@@ -320,7 +312,6 @@ static int autofs4_revalidate(struct den

return status;
}
- spin_unlock(&dcache_lock);

return 1;
}
@@ -372,7 +363,6 @@ static struct dentry *autofs4_lookup_act
const unsigned char *str = name->name;
struct list_head *p, *head;

- spin_lock(&dcache_lock);
spin_lock(&sbi->lookup_lock);
head = &sbi->active_list;
list_for_each(p, head) {
@@ -405,14 +395,12 @@ static struct dentry *autofs4_lookup_act
dget_locked_dlock(dentry);
spin_unlock(&dentry->d_lock);
spin_unlock(&sbi->lookup_lock);
- spin_unlock(&dcache_lock);
return dentry;
}
next:
spin_unlock(&dentry->d_lock);
}
spin_unlock(&sbi->lookup_lock);
- spin_unlock(&dcache_lock);

return NULL;
}
@@ -424,7 +412,6 @@ static struct dentry *autofs4_lookup_exp
const unsigned char *str = name->name;
struct list_head *p, *head;

- spin_lock(&dcache_lock);
spin_lock(&sbi->lookup_lock);
head = &sbi->expiring_list;
list_for_each(p, head) {
@@ -457,14 +444,12 @@ static struct dentry *autofs4_lookup_exp
dget_locked_dlock(dentry);
spin_unlock(&dentry->d_lock);
spin_unlock(&sbi->lookup_lock);
- spin_unlock(&dcache_lock);
return dentry;
}
next:
spin_unlock(&dentry->d_lock);
}
spin_unlock(&sbi->lookup_lock);
- spin_unlock(&dcache_lock);

return NULL;
}
@@ -710,7 +695,6 @@ static int autofs4_dir_unlink(struct ino

dir->i_mtime = CURRENT_TIME;

- spin_lock(&dcache_lock);
spin_lock(&sbi->lookup_lock);
if (list_empty(&ino->expiring))
list_add(&ino->expiring, &sbi->expiring_list);
@@ -718,7 +702,6 @@ static int autofs4_dir_unlink(struct ino
spin_lock(&dentry->d_lock);
__d_drop(dentry);
spin_unlock(&dentry->d_lock);
- spin_unlock(&dcache_lock);

return 0;
}
@@ -735,11 +718,9 @@ static int autofs4_dir_rmdir(struct inod
if (!autofs4_oz_mode(sbi))
return -EACCES;

- spin_lock(&dcache_lock);
spin_lock(&dentry->d_lock);
if (!list_empty(&dentry->d_subdirs)) {
spin_unlock(&dentry->d_lock);
- spin_unlock(&dcache_lock);
return -ENOTEMPTY;
}
spin_lock(&sbi->lookup_lock);
@@ -748,7 +729,6 @@ static int autofs4_dir_rmdir(struct inod
spin_unlock(&sbi->lookup_lock);
__d_drop(dentry);
spin_unlock(&dentry->d_lock);
- spin_unlock(&dcache_lock);

if (atomic_dec_and_test(&ino->count)) {
p_ino = autofs4_dentry_ino(dentry->d_parent);
Index: linux-2.6/fs/coda/cache.c
===================================================================
--- linux-2.6.orig/fs/coda/cache.c
+++ linux-2.6/fs/coda/cache.c
@@ -86,7 +86,6 @@ static void coda_flag_children(struct de
struct list_head *child;
struct dentry *de;

- spin_lock(&dcache_lock);
spin_lock(&parent->d_lock);
list_for_each(child, &parent->d_subdirs)
{
@@ -97,7 +96,6 @@ static void coda_flag_children(struct de
coda_flag_inode(de->d_inode, flag);
}
spin_unlock(&parent->d_lock);
- spin_unlock(&dcache_lock);
return;
}

Index: linux-2.6/fs/configfs/configfs_internal.h
===================================================================
--- linux-2.6.orig/fs/configfs/configfs_internal.h
+++ linux-2.6/fs/configfs/configfs_internal.h
@@ -120,7 +120,6 @@ static inline struct config_item *config
{
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 *config
item = config_item_get(sd->s_element);
}
spin_unlock(&dentry->d_lock);
- spin_unlock(&dcache_lock);

return item;
}
Index: linux-2.6/fs/configfs/inode.c
===================================================================
--- linux-2.6.orig/fs/configfs/inode.c
+++ linux-2.6/fs/configfs/inode.c
@@ -253,18 +253,14 @@ void configfs_drop_dentry(struct configf
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);
- }
}
}

Index: linux-2.6/fs/ncpfs/dir.c
===================================================================
--- linux-2.6.orig/fs/ncpfs/dir.c
+++ linux-2.6/fs/ncpfs/dir.c
@@ -364,7 +364,6 @@ ncp_dget_fpos(struct dentry *dentry, str
}

/* 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) {
@@ -375,13 +374,11 @@ ncp_dget_fpos(struct dentry *dentry, str
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:
Index: linux-2.6/fs/ncpfs/ncplib_kernel.h
===================================================================
--- linux-2.6.orig/fs/ncpfs/ncplib_kernel.h
+++ linux-2.6/fs/ncpfs/ncplib_kernel.h
@@ -192,7 +192,6 @@ 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) {
@@ -206,7 +205,6 @@ ncp_renew_dentries(struct dentry *parent
next = next->next;
}
spin_unlock(&parent->d_lock);
- spin_unlock(&dcache_lock);
}

static inline void
@@ -216,7 +214,6 @@ ncp_invalidate_dircache_entries(struct d
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) {
@@ -226,7 +223,6 @@ ncp_invalidate_dircache_entries(struct d
next = next->next;
}
spin_unlock(&parent->d_lock);
- spin_unlock(&dcache_lock);
}

struct ncp_cache_head {
Index: linux-2.6/fs/nfs/dir.c
===================================================================
--- linux-2.6.orig/fs/nfs/dir.c
+++ linux-2.6/fs/nfs/dir.c
@@ -1432,11 +1432,9 @@ static int nfs_unlink(struct inode *dir,
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);
@@ -1447,7 +1445,6 @@ static int nfs_unlink(struct inode *dir,
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));
Index: linux-2.6/fs/ocfs2/dcache.c
===================================================================
--- linux-2.6.orig/fs/ocfs2/dcache.c
+++ linux-2.6/fs/ocfs2/dcache.c
@@ -140,7 +140,6 @@ struct dentry *ocfs2_find_local_alias(st
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);
@@ -160,7 +159,6 @@ struct dentry *ocfs2_find_local_alias(st
}

spin_unlock(&dcache_inode_lock);
- spin_unlock(&dcache_lock);

return dentry;
}
Index: linux-2.6/fs/smbfs/cache.c
===================================================================
--- linux-2.6.orig/fs/smbfs/cache.c
+++ linux-2.6/fs/smbfs/cache.c
@@ -62,7 +62,6 @@ smb_invalidate_dircache_entries(struct d
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 d
next = next->next;
}
spin_unlock(&parent->d_lock);
- spin_unlock(&dcache_lock);
}

/*
@@ -98,7 +96,6 @@ smb_dget_fpos(struct dentry *dentry, str
}

/* 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, str
dent = NULL;
out_unlock:
spin_unlock(&parent->d_lock);
- spin_unlock(&dcache_lock);
return dent;
}

Index: linux-2.6/kernel/cgroup.c
===================================================================
--- linux-2.6.orig/kernel/cgroup.c
+++ linux-2.6/kernel/cgroup.c
@@ -695,7 +695,6 @@ static void cgroup_clear_directory(struc
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) {
@@ -710,18 +709,15 @@ static void cgroup_clear_directory(struc
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);
}

/*
@@ -733,14 +729,12 @@ static void cgroup_d_remove_dir(struct d

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);
}

Index: linux-2.6/net/sunrpc/rpc_pipe.c
===================================================================
--- linux-2.6.orig/net/sunrpc/rpc_pipe.c
+++ linux-2.6/net/sunrpc/rpc_pipe.c
@@ -547,15 +547,14 @@ static void rpc_depopulate(struct dentry

mutex_lock_nested(&dir->i_mutex, I_MUTEX_CHILD);
repeat:
- spin_lock(&dcache_lock);
spin_lock(&parent->d_lock);
list_for_each_safe(pos, next, &parent->d_subdirs) {
dentry = list_entry(pos, struct dentry, d_u.d_child);
+ spin_lock(&dentry->d_lock);
if (!dentry->d_inode ||
dentry->d_inode->i_ino < start ||
dentry->d_inode->i_ino >= eof)
- continue;
- spin_lock(&dentry->d_lock);
+ goto next;
if (!d_unhashed(dentry)) {
dget_locked_dlock(dentry);
__d_drop(dentry);
@@ -563,11 +562,11 @@ repeat:
dvec[n++] = dentry;
if (n == ARRAY_SIZE(dvec))
break;
- } else
- spin_unlock(&dentry->d_lock);
+ }
+next:
+ spin_unlock(&dentry->d_lock);
}
spin_unlock(&parent->d_lock);
- spin_unlock(&dcache_lock);
if (n) {
do {
dentry = dvec[--n];
Index: linux-2.6/security/selinux/selinuxfs.c
===================================================================
--- linux-2.6.orig/security/selinux/selinuxfs.c
+++ linux-2.6/security/selinux/selinuxfs.c
@@ -943,7 +943,6 @@ static void sel_remove_entries(struct de
{
struct list_head *node;

- spin_lock(&dcache_lock);
spin_lock(&de->d_lock);
node = de->d_subdirs.next;
while (node != &de->d_subdirs) {
@@ -956,11 +955,9 @@ static void sel_remove_entries(struct 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);
@@ -968,7 +965,6 @@ static void sel_remove_entries(struct de
}

spin_unlock(&de->d_lock);
- spin_unlock(&dcache_lock);
}

#define BOOL_DIR_NAME "booleans"
Index: linux-2.6/security/tomoyo/realpath.c
===================================================================
--- linux-2.6.orig/security/tomoyo/realpath.c
+++ linux-2.6/security/tomoyo/realpath.c
@@ -102,10 +102,8 @@ int tomoyo_realpath_from_path2(struct pa
if (ns_root.mnt)
ns_root.dentry = dget(ns_root.mnt->mnt_root);
vfsmount_read_unlock();
- spin_lock(&dcache_lock);
tmp = ns_root;
sp = __d_path(path, &tmp, newname, newname_len);
- spin_unlock(&dcache_lock);
path_put(&root);
path_put(&ns_root);
}
Index: linux-2.6/fs/nfs/getroot.c
===================================================================
--- linux-2.6.orig/fs/nfs/getroot.c
+++ linux-2.6/fs/nfs/getroot.c
@@ -64,13 +64,11 @@ static int nfs_superblock_set_dummy_root
* 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;
}
Index: linux-2.6/drivers/staging/pohmelfs/path_entry.c
===================================================================
--- linux-2.6.orig/drivers/staging/pohmelfs/path_entry.c
+++ linux-2.6/drivers/staging/pohmelfs/path_entry.c
@@ -100,7 +100,6 @@ int pohmelfs_path_length(struct pohmelfs
rcu_read_lock();
rename_retry:
seq = read_seqbegin(&rename_lock);
- spin_lock(&dcache_lock);

if (!IS_ROOT(d) && d_unhashed(d))
len += UNHASHED_OBSCURE_STRING_SIZE; /* Obscure " (deleted)" string */
@@ -109,7 +108,6 @@ rename_retry:
len += d->d_name.len + 1; /* Plus slash */
d = d->d_parent;
}
- spin_unlock(&dcache_lock);
if (read_seqretry(&rename_lock, seq))
goto rename_retry;
rcu_read_unlock();
Index: linux-2.6/fs/autofs4/waitq.c
===================================================================
--- linux-2.6.orig/fs/autofs4/waitq.c
+++ linux-2.6/fs/autofs4/waitq.c
@@ -194,12 +194,10 @@ static int autofs4_getpath(struct autofs
rcu_read_lock();
rename_retry:
seq = read_seqbegin(&rename_lock);
- spin_lock(&dcache_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);
if (read_seqretry(&rename_lock, seq))
goto rename_retry;
rcu_read_unlock();
@@ -215,7 +213,6 @@ rename_retry:
p -= tmp->d_name.len;
strncpy(p, tmp->d_name.name, tmp->d_name.len);
}
- spin_unlock(&dcache_lock);
if (read_seqretry(&rename_lock, seq))
goto rename_retry;
rcu_read_unlock();
Index: linux-2.6/fs/nfs/namespace.c
===================================================================
--- linux-2.6.orig/fs/nfs/namespace.c
+++ linux-2.6/fs/nfs/namespace.c
@@ -57,7 +57,6 @@ char *nfs_path(const char *base,
rcu_read_lock();
rename_retry:
seq = read_seqbegin(&rename_lock);
- spin_lock(&dcache_lock);
while (!IS_ROOT(dentry) && dentry != droot) {
namelen = dentry->d_name.len;
buflen -= namelen + 1;
@@ -68,7 +67,6 @@ rename_retry:
*--end = '/';
dentry = dentry->d_parent;
}
- spin_unlock(&dcache_lock);
if (read_seqretry(&rename_lock, seq))
goto rename_retry;
rcu_read_unlock();
@@ -88,7 +86,6 @@ rename_retry:
memcpy(end, base, namelen);
return end;
Elong_unlock:
- spin_unlock(&dcache_lock);
if (read_seqretry(&rename_lock, seq))
goto rename_retry;
rcu_read_unlock();
Index: linux-2.6/include/linux/fsnotify_backend.h
===================================================================
--- linux-2.6.orig/include/linux/fsnotify_backend.h
+++ linux-2.6/include/linux/fsnotify_backend.h
@@ -276,10 +276,10 @@ static inline void __fsnotify_update_dca
{
struct dentry *parent;

- assert_spin_locked(&dcache_lock);
assert_spin_locked(&dentry->d_lock);

parent = dentry->d_parent;
+ /* XXX: after dcache_lock removal, there is a race with parent->d_inode and fsnotify_inode_watches_children. must fix */
if (parent->d_inode && fsnotify_inode_watches_children(parent->d_inode))
dentry->d_flags |= DCACHE_FSNOTIFY_PARENT_WATCHED;
else
@@ -288,15 +288,12 @@ static inline void __fsnotify_update_dca

/*
* 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);
Index: linux-2.6/fs/notify/fsnotify.c
===================================================================
--- linux-2.6.orig/fs/notify/fsnotify.c
+++ linux-2.6/fs/notify/fsnotify.c
@@ -52,7 +52,6 @@ void __fsnotify_update_child_dentry_flag
/* 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 */
@@ -77,7 +76,6 @@ void __fsnotify_update_child_dentry_flag
spin_unlock(&alias->d_lock);
}
spin_unlock(&dcache_inode_lock);
- spin_unlock(&dcache_lock);
}

/* Notify this dentry's parent about a child's events. */


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