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authorLinus Torvalds <torvalds@linux-foundation.org>2013-03-03 13:23:02 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2013-03-03 13:23:03 -0800
commit56a79b7b021bf1b08334e63c2c14b280e2dbf47a (patch)
tree0419233e6194f4f12073c9284852885aa8984bec /fs/9p
parent1c82315a12144cde732636e259d39e3ee81b3c5b (diff)
parentdcf787f39162ce32ca325b3e784aba2d2444619a (diff)
downloadlinux-56a79b7b021bf1b08334e63c2c14b280e2dbf47a.tar.bz2
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull more VFS bits from Al Viro: "Unfortunately, it looks like xattr series will have to wait until the next cycle ;-/ This pile contains 9p cleanups and fixes (races in v9fs_fid_add() etc), fixup for nommu breakage in shmem.c, several cleanups and a bit more file_inode() work" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: constify path_get/path_put and fs_struct.c stuff fix nommu breakage in shmem.c cache the value of file_inode() in struct file 9p: if v9fs_fid_lookup() gets to asking server, it'd better have hashed dentry 9p: make sure ->lookup() adds fid to the right dentry 9p: untangle ->lookup() a bit 9p: double iput() in ->lookup() if d_materialise_unique() fails 9p: v9fs_fid_add() can't fail now v9fs: get rid of v9fs_dentry 9p: turn fid->dlist into hlist 9p: don't bother with private lock in ->d_fsdata; dentry->d_lock will do just fine more file_inode() open-coded instances selinux: opened file can't have NULL or negative ->f_path.dentry (In the meantime, the hlist traversal macros have changed, so this required a semantic conflict fixup for the newly hlistified fid->dlist)
Diffstat (limited to 'fs/9p')
-rw-r--r--fs/9p/fid.c54
-rw-r--r--fs/9p/fid.h22
-rw-r--r--fs/9p/vfs_dentry.c17
-rw-r--r--fs/9p/vfs_inode.c40
-rw-r--r--fs/9p/vfs_inode_dotl.c19
5 files changed, 51 insertions, 101 deletions
diff --git a/fs/9p/fid.c b/fs/9p/fid.c
index afd4724b2d92..d51ec9fafcc8 100644
--- a/fs/9p/fid.c
+++ b/fs/9p/fid.c
@@ -41,29 +41,16 @@
*
*/
-int v9fs_fid_add(struct dentry *dentry, struct p9_fid *fid)
+static inline void __add_fid(struct dentry *dentry, struct p9_fid *fid)
{
- struct v9fs_dentry *dent;
-
- p9_debug(P9_DEBUG_VFS, "fid %d dentry %s\n",
- fid->fid, dentry->d_name.name);
-
- dent = dentry->d_fsdata;
- if (!dent) {
- dent = kmalloc(sizeof(struct v9fs_dentry), GFP_KERNEL);
- if (!dent)
- return -ENOMEM;
-
- spin_lock_init(&dent->lock);
- INIT_LIST_HEAD(&dent->fidlist);
- dentry->d_fsdata = dent;
- }
-
- spin_lock(&dent->lock);
- list_add(&fid->dlist, &dent->fidlist);
- spin_unlock(&dent->lock);
+ hlist_add_head(&fid->dlist, (struct hlist_head *)&dentry->d_fsdata);
+}
- return 0;
+void v9fs_fid_add(struct dentry *dentry, struct p9_fid *fid)
+{
+ spin_lock(&dentry->d_lock);
+ __add_fid(dentry, fid);
+ spin_unlock(&dentry->d_lock);
}
/**
@@ -76,23 +63,23 @@ int v9fs_fid_add(struct dentry *dentry, struct p9_fid *fid)
static struct p9_fid *v9fs_fid_find(struct dentry *dentry, kuid_t uid, int any)
{
- struct v9fs_dentry *dent;
struct p9_fid *fid, *ret;
p9_debug(P9_DEBUG_VFS, " dentry: %s (%p) uid %d any %d\n",
dentry->d_name.name, dentry, from_kuid(&init_user_ns, uid),
any);
- dent = (struct v9fs_dentry *) dentry->d_fsdata;
ret = NULL;
- if (dent) {
- spin_lock(&dent->lock);
- list_for_each_entry(fid, &dent->fidlist, dlist) {
+ /* we'll recheck under lock if there's anything to look in */
+ if (dentry->d_fsdata) {
+ struct hlist_head *h = (struct hlist_head *)&dentry->d_fsdata;
+ spin_lock(&dentry->d_lock);
+ hlist_for_each_entry(fid, h, dlist) {
if (any || uid_eq(fid->uid, uid)) {
ret = fid;
break;
}
}
- spin_unlock(&dent->lock);
+ spin_unlock(&dentry->d_lock);
}
return ret;
@@ -215,8 +202,17 @@ static struct p9_fid *v9fs_fid_lookup_with_uid(struct dentry *dentry,
}
kfree(wnames);
fid_out:
- if (!IS_ERR(fid))
- v9fs_fid_add(dentry, fid);
+ if (!IS_ERR(fid)) {
+ spin_lock(&dentry->d_lock);
+ if (d_unhashed(dentry)) {
+ spin_unlock(&dentry->d_lock);
+ p9_client_clunk(fid);
+ fid = ERR_PTR(-ENOENT);
+ } else {
+ __add_fid(dentry, fid);
+ spin_unlock(&dentry->d_lock);
+ }
+ }
err_out:
up_read(&v9ses->rename_sem);
return fid;
diff --git a/fs/9p/fid.h b/fs/9p/fid.h
index bb0b6e7f58fc..2b6787fcb626 100644
--- a/fs/9p/fid.h
+++ b/fs/9p/fid.h
@@ -23,28 +23,8 @@
#define FS_9P_FID_H
#include <linux/list.h>
-/**
- * struct v9fs_dentry - 9p private data stored in dentry d_fsdata
- * @lock: protects the fidlist
- * @fidlist: list of FIDs currently associated with this dentry
- *
- * This structure defines the 9p private data associated with
- * a particular dentry. In particular, this private data is used
- * to lookup which 9P FID handle should be used for a particular VFS
- * operation. FID handles are associated with dentries instead of
- * inodes in order to more closely map functionality to the Plan 9
- * expected behavior for FID reclaimation and tracking.
- *
- * See Also: Mapping FIDs to Linux VFS model in
- * Design and Implementation of the Linux 9P File System documentation
- */
-struct v9fs_dentry {
- spinlock_t lock; /* protect fidlist */
- struct list_head fidlist;
-};
-
struct p9_fid *v9fs_fid_lookup(struct dentry *dentry);
struct p9_fid *v9fs_fid_clone(struct dentry *dentry);
-int v9fs_fid_add(struct dentry *dentry, struct p9_fid *fid);
+void v9fs_fid_add(struct dentry *dentry, struct p9_fid *fid);
struct p9_fid *v9fs_writeback_fid(struct dentry *dentry);
#endif
diff --git a/fs/9p/vfs_dentry.c b/fs/9p/vfs_dentry.c
index 9ad68628522c..f039b104a98e 100644
--- a/fs/9p/vfs_dentry.c
+++ b/fs/9p/vfs_dentry.c
@@ -83,21 +83,12 @@ static int v9fs_cached_dentry_delete(const struct dentry *dentry)
static void v9fs_dentry_release(struct dentry *dentry)
{
- struct v9fs_dentry *dent;
- struct p9_fid *temp, *current_fid;
-
+ struct hlist_node *p, *n;
p9_debug(P9_DEBUG_VFS, " dentry: %s (%p)\n",
dentry->d_name.name, dentry);
- dent = dentry->d_fsdata;
- if (dent) {
- list_for_each_entry_safe(current_fid, temp, &dent->fidlist,
- dlist) {
- p9_client_clunk(current_fid);
- }
-
- kfree(dent);
- dentry->d_fsdata = NULL;
- }
+ hlist_for_each_safe(p, n, (struct hlist_head *)&dentry->d_fsdata)
+ p9_client_clunk(hlist_entry(p, struct p9_fid, dlist));
+ dentry->d_fsdata = NULL;
}
static int v9fs_lookup_revalidate(struct dentry *dentry, unsigned int flags)
diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c
index b5340c829de1..d86edc8d3fd0 100644
--- a/fs/9p/vfs_inode.c
+++ b/fs/9p/vfs_inode.c
@@ -692,9 +692,7 @@ v9fs_create(struct v9fs_session_info *v9ses, struct inode *dir,
"inode creation failed %d\n", err);
goto error;
}
- err = v9fs_fid_add(dentry, fid);
- if (err < 0)
- goto error;
+ v9fs_fid_add(dentry, fid);
d_instantiate(dentry, inode);
}
return ofid;
@@ -790,7 +788,6 @@ struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry,
struct p9_fid *dfid, *fid;
struct inode *inode;
char *name;
- int result = 0;
p9_debug(P9_DEBUG_VFS, "dir: %p dentry: (%s) %p flags: %x\n",
dir, dentry->d_name.name, dentry, flags);
@@ -808,13 +805,11 @@ struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry,
name = (char *) dentry->d_name.name;
fid = p9_client_walk(dfid, 1, &name, 1);
if (IS_ERR(fid)) {
- result = PTR_ERR(fid);
- if (result == -ENOENT) {
- inode = NULL;
- goto inst_out;
+ if (fid == ERR_PTR(-ENOENT)) {
+ d_add(dentry, NULL);
+ return NULL;
}
-
- return ERR_PTR(result);
+ return ERR_CAST(fid);
}
/*
* Make sure we don't use a wrong inode due to parallel
@@ -826,14 +821,9 @@ struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry,
else
inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
if (IS_ERR(inode)) {
- result = PTR_ERR(inode);
- inode = NULL;
- goto error;
+ p9_client_clunk(fid);
+ return ERR_CAST(inode);
}
- result = v9fs_fid_add(dentry, fid);
- if (result < 0)
- goto error_iput;
-inst_out:
/*
* If we had a rename on the server and a parallel lookup
* for the new name, then make sure we instantiate with
@@ -842,15 +832,13 @@ inst_out:
* k/b.
*/
res = d_materialise_unique(dentry, inode);
- if (!IS_ERR(res))
- return res;
- result = PTR_ERR(res);
-error_iput:
- iput(inode);
-error:
- p9_client_clunk(fid);
-
- return ERR_PTR(result);
+ if (!res)
+ v9fs_fid_add(dentry, fid);
+ else if (!IS_ERR(res))
+ v9fs_fid_add(res, fid);
+ else
+ p9_client_clunk(fid);
+ return res;
}
static int
diff --git a/fs/9p/vfs_inode_dotl.c b/fs/9p/vfs_inode_dotl.c
index 61e4fa70a6fa..53687bbf2296 100644
--- a/fs/9p/vfs_inode_dotl.c
+++ b/fs/9p/vfs_inode_dotl.c
@@ -333,9 +333,7 @@ v9fs_vfs_atomic_open_dotl(struct inode *dir, struct dentry *dentry,
/* Now set the ACL based on the default value */
v9fs_set_create_acl(inode, fid, dacl, pacl);
- err = v9fs_fid_add(dentry, fid);
- if (err < 0)
- goto error;
+ v9fs_fid_add(dentry, fid);
d_instantiate(dentry, inode);
v9inode = V9FS_I(inode);
@@ -453,12 +451,11 @@ static int v9fs_vfs_mkdir_dotl(struct inode *dir,
err);
goto error;
}
- err = v9fs_fid_add(dentry, fid);
- if (err < 0)
- goto error;
+ v9fs_fid_add(dentry, fid);
v9fs_set_create_acl(inode, fid, dacl, pacl);
d_instantiate(dentry, inode);
fid = NULL;
+ err = 0;
} else {
/*
* Not in cached mode. No need to populate
@@ -747,11 +744,10 @@ v9fs_vfs_symlink_dotl(struct inode *dir, struct dentry *dentry,
err);
goto error;
}
- err = v9fs_fid_add(dentry, fid);
- if (err < 0)
- goto error;
+ v9fs_fid_add(dentry, fid);
d_instantiate(dentry, inode);
fid = NULL;
+ err = 0;
} else {
/* Not in cached mode. No need to populate inode with stat */
inode = v9fs_get_inode(dir->i_sb, S_IFLNK, 0);
@@ -900,11 +896,10 @@ v9fs_vfs_mknod_dotl(struct inode *dir, struct dentry *dentry, umode_t omode,
goto error;
}
v9fs_set_create_acl(inode, fid, dacl, pacl);
- err = v9fs_fid_add(dentry, fid);
- if (err < 0)
- goto error;
+ v9fs_fid_add(dentry, fid);
d_instantiate(dentry, inode);
fid = NULL;
+ err = 0;
} else {
/*
* Not in cached mode. No need to populate inode with stat.