fs: provide rcu-walk aware permission i_ops
Signed-off-by: Nick Piggin <npiggin@kernel.dk>
diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking
index e90ffe6..977d891 100644
--- a/Documentation/filesystems/Locking
+++ b/Documentation/filesystems/Locking
@@ -47,8 +47,8 @@
void * (*follow_link) (struct dentry *, struct nameidata *);
void (*put_link) (struct dentry *, struct nameidata *, void *);
void (*truncate) (struct inode *);
- int (*permission) (struct inode *, int, struct nameidata *);
- int (*check_acl)(struct inode *, int);
+ int (*permission) (struct inode *, int, unsigned int);
+ int (*check_acl)(struct inode *, int, unsigned int);
int (*setattr) (struct dentry *, struct iattr *);
int (*getattr) (struct vfsmount *, struct dentry *, struct kstat *);
int (*setxattr) (struct dentry *, const char *,const void *,size_t,int);
@@ -76,7 +76,7 @@
put_link: no
truncate: yes (see below)
setattr: yes
-permission: no
+permission: no (may not block if called in rcu-walk mode)
check_acl: no
getattr: no
setxattr: yes
diff --git a/Documentation/filesystems/path-lookup.txt b/Documentation/filesystems/path-lookup.txt
index 8789d18..eb59c8b 100644
--- a/Documentation/filesystems/path-lookup.txt
+++ b/Documentation/filesystems/path-lookup.txt
@@ -316,11 +316,9 @@
The cases where rcu-walk cannot continue are:
* NULL dentry (ie. any uncached path element)
-* parent with d_inode->i_op->permission or ACLs
* Following links
-In future patches, permission checks become rcu-walk aware. It may be possible
-eventually to make following links rcu-walk aware.
+It may be possible eventually to make following links rcu-walk aware.
Uncached path elements will always require dropping to ref-walk mode, at the
very least because i_mutex needs to be grabbed, and objects allocated.
@@ -336,9 +334,49 @@
scalability of path resolution.
+Interesting statistics
+======================
+
+The following table gives rcu lookup statistics for a few simple workloads
+(2s12c24t Westmere, debian non-graphical system). Ungraceful are attempts to
+drop rcu that fail due to d_seq failure and requiring the entire path lookup
+again. Other cases are successful rcu-drops that are required before the final
+element, nodentry for missing dentry, revalidate for filesystem revalidate
+routine requiring rcu drop, permission for permission check requiring drop,
+and link for symlink traversal requiring drop.
+
+ rcu-lookups restart nodentry link revalidate permission
+bootup 47121 0 4624 1010 10283 7852
+dbench 25386793 0 6778659(26.7%) 55 549 1156
+kbuild 2696672 10 64442(2.3%) 108764(4.0%) 1 1590
+git diff 39605 0 28 2 0 106
+vfstest 24185492 4945 708725(2.9%) 1076136(4.4%) 0 2651
+
+What this shows is that failed rcu-walk lookups, ie. ones that are restarted
+entirely with ref-walk, are quite rare. Even the "vfstest" case which
+specifically has concurrent renames/mkdir/rmdir/ creat/unlink/etc to excercise
+such races is not showing a huge amount of restarts.
+
+Dropping from rcu-walk to ref-walk mean that we have encountered a dentry where
+the reference count needs to be taken for some reason. This is either because
+we have reached the target of the path walk, or because we have encountered a
+condition that can't be resolved in rcu-walk mode. Ideally, we drop rcu-walk
+only when we have reached the target dentry, so the other statistics show where
+this does not happen.
+
+Note that a graceful drop from rcu-walk mode due to something such as the
+dentry not existing (which can be common) is not necessarily a failure of
+rcu-walk scheme, because some elements of the path may have been walked in
+rcu-walk mode. The further we get from common path elements (such as cwd or
+root), the less contended the dentry is likely to be. The closer we are to
+common path elements, the more likely they will exist in dentry cache.
+
+
Papers and other documentation on dcache locking
================================================
1. Scaling dcache with RCU (http://linuxjournal.com/article.php?sid=7124).
2. http://lse.sourceforge.net/locking/dcache/dcache.html
+
+
diff --git a/Documentation/filesystems/porting b/Documentation/filesystems/porting
index cd9756a..07a32b4 100644
--- a/Documentation/filesystems/porting
+++ b/Documentation/filesystems/porting
@@ -380,3 +380,8 @@
may now be called in rcu-walk mode (nd->flags & LOOKUP_RCU). -ECHILD should be
returned if the filesystem cannot handle rcu-walk. See
Documentation/filesystems/vfs.txt for more details.
+
+ permission and check_acl are inode permission checks that are called
+on many or all directory inodes on the way down a path walk (to check for
+exec permission). These must now be rcu-walk aware (flags & IPERM_RCU). See
+Documentation/filesystems/vfs.txt for more details.
diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt
index c936b49..fbb324e 100644
--- a/Documentation/filesystems/vfs.txt
+++ b/Documentation/filesystems/vfs.txt
@@ -325,7 +325,8 @@
void * (*follow_link) (struct dentry *, struct nameidata *);
void (*put_link) (struct dentry *, struct nameidata *, void *);
void (*truncate) (struct inode *);
- int (*permission) (struct inode *, int, struct nameidata *);
+ int (*permission) (struct inode *, int, unsigned int);
+ int (*check_acl)(struct inode *, int, unsigned int);
int (*setattr) (struct dentry *, struct iattr *);
int (*getattr) (struct vfsmount *mnt, struct dentry *, struct kstat *);
int (*setxattr) (struct dentry *, const char *,const void *,size_t,int);
@@ -414,6 +415,13 @@
permission: called by the VFS to check for access rights on a POSIX-like
filesystem.
+ May be called in rcu-walk mode (flags & IPERM_RCU). If in rcu-walk
+ mode, the filesystem must check the permission without blocking or
+ storing to the inode.
+
+ If a situation is encountered that rcu-walk cannot handle, return
+ -ECHILD and it will be called again in ref-walk mode.
+
setattr: called by the VFS to set attributes for a file. This method
is called by chmod(2) and related system calls.
diff --git a/drivers/staging/smbfs/file.c b/drivers/staging/smbfs/file.c
index 5dcd19c..31372e7 100644
--- a/drivers/staging/smbfs/file.c
+++ b/drivers/staging/smbfs/file.c
@@ -407,11 +407,14 @@
* privileges, so we need our own check for this.
*/
static int
-smb_file_permission(struct inode *inode, int mask)
+smb_file_permission(struct inode *inode, int mask, unsigned int flags)
{
int mode = inode->i_mode;
int error = 0;
+ if (flags & IPERM_FLAG_RCU)
+ return -ECHILD;
+
VERBOSE("mode=%x, mask=%x\n", mode, mask);
/* Look at user permissions */
diff --git a/fs/9p/acl.c b/fs/9p/acl.c
index 12d6023..6e58c4c 100644
--- a/fs/9p/acl.c
+++ b/fs/9p/acl.c
@@ -91,11 +91,14 @@
return acl;
}
-int v9fs_check_acl(struct inode *inode, int mask)
+int v9fs_check_acl(struct inode *inode, int mask, unsigned int flags)
{
struct posix_acl *acl;
struct v9fs_session_info *v9ses;
+ if (flags & IPERM_FLAG_RCU)
+ return -ECHILD;
+
v9ses = v9fs_inode2v9ses(inode);
if ((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT) {
/*
diff --git a/fs/9p/acl.h b/fs/9p/acl.h
index 59e18c2..7ef3ac9 100644
--- a/fs/9p/acl.h
+++ b/fs/9p/acl.h
@@ -16,7 +16,7 @@
#ifdef CONFIG_9P_FS_POSIX_ACL
extern int v9fs_get_acl(struct inode *, struct p9_fid *);
-extern int v9fs_check_acl(struct inode *inode, int mask);
+extern int v9fs_check_acl(struct inode *inode, int mask, unsigned int flags);
extern int v9fs_acl_chmod(struct dentry *);
extern int v9fs_set_create_acl(struct dentry *,
struct posix_acl *, struct posix_acl *);
diff --git a/fs/afs/internal.h b/fs/afs/internal.h
index cca8eef..6d4bc1c 100644
--- a/fs/afs/internal.h
+++ b/fs/afs/internal.h
@@ -624,7 +624,7 @@
extern void afs_cache_permit(struct afs_vnode *, struct key *, long);
extern void afs_zap_permits(struct rcu_head *);
extern struct key *afs_request_key(struct afs_cell *);
-extern int afs_permission(struct inode *, int);
+extern int afs_permission(struct inode *, int, unsigned int);
/*
* server.c
diff --git a/fs/afs/security.c b/fs/afs/security.c
index bb4ed14..f44b9d3 100644
--- a/fs/afs/security.c
+++ b/fs/afs/security.c
@@ -285,13 +285,16 @@
* - AFS ACLs are attached to directories only, and a file is controlled by its
* parent directory's ACL
*/
-int afs_permission(struct inode *inode, int mask)
+int afs_permission(struct inode *inode, int mask, unsigned int flags)
{
struct afs_vnode *vnode = AFS_FS_I(inode);
afs_access_t uninitialized_var(access);
struct key *key;
int ret;
+ if (flags & IPERM_FLAG_RCU)
+ return -ECHILD;
+
_enter("{{%x:%u},%lx},%x,",
vnode->fid.vid, vnode->fid.vnode, vnode->flags, mask);
@@ -347,7 +350,7 @@
}
key_put(key);
- ret = generic_permission(inode, mask, NULL);
+ ret = generic_permission(inode, mask, flags, NULL);
_leave(" = %d", ret);
return ret;
diff --git a/fs/bad_inode.c b/fs/bad_inode.c
index f024d8a..9ad2369 100644
--- a/fs/bad_inode.c
+++ b/fs/bad_inode.c
@@ -229,8 +229,11 @@
return -EIO;
}
-static int bad_inode_permission(struct inode *inode, int mask)
+static int bad_inode_permission(struct inode *inode, int mask, unsigned int flags)
{
+ if (flags & IPERM_FLAG_RCU)
+ return -ECHILD;
+
return -EIO;
}
diff --git a/fs/btrfs/acl.c b/fs/btrfs/acl.c
index 2222d16..cb518a4 100644
--- a/fs/btrfs/acl.c
+++ b/fs/btrfs/acl.c
@@ -185,13 +185,15 @@
return ret;
}
-int btrfs_check_acl(struct inode *inode, int mask)
+int btrfs_check_acl(struct inode *inode, int mask, unsigned int flags)
{
struct posix_acl *acl;
int error = -EAGAIN;
- acl = btrfs_get_acl(inode, ACL_TYPE_ACCESS);
+ if (flags & IPERM_FLAG_RCU)
+ return -ECHILD;
+ acl = btrfs_get_acl(inode, ACL_TYPE_ACCESS);
if (IS_ERR(acl))
return PTR_ERR(acl);
if (acl) {
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index af52f6d..a142d20 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -2544,7 +2544,7 @@
/* acl.c */
#ifdef CONFIG_BTRFS_FS_POSIX_ACL
-int btrfs_check_acl(struct inode *inode, int mask);
+int btrfs_check_acl(struct inode *inode, int mask, unsigned int flags);
#else
#define btrfs_check_acl NULL
#endif
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 63e4546..5cf0db0 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -7211,11 +7211,14 @@
return __set_page_dirty_nobuffers(page);
}
-static int btrfs_permission(struct inode *inode, int mask)
+static int btrfs_permission(struct inode *inode, int mask, unsigned int flags)
{
+ if (flags & IPERM_FLAG_RCU)
+ return -ECHILD;
+
if ((BTRFS_I(inode)->flags & BTRFS_INODE_READONLY) && (mask & MAY_WRITE))
return -EACCES;
- return generic_permission(inode, mask, btrfs_check_acl);
+ return generic_permission(inode, mask, flags, btrfs_check_acl);
}
static const struct inode_operations btrfs_dir_inode_operations = {
diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
index 47f8c8b..e61de4f 100644
--- a/fs/ceph/inode.c
+++ b/fs/ceph/inode.c
@@ -1781,12 +1781,17 @@
* Check inode permissions. We verify we have a valid value for
* the AUTH cap, then call the generic handler.
*/
-int ceph_permission(struct inode *inode, int mask)
+int ceph_permission(struct inode *inode, int mask, unsigned int flags)
{
- int err = ceph_do_getattr(inode, CEPH_CAP_AUTH_SHARED);
+ int err;
+
+ if (flags & IPERM_FLAG_RCU)
+ return -ECHILD;
+
+ err = ceph_do_getattr(inode, CEPH_CAP_AUTH_SHARED);
if (!err)
- err = generic_permission(inode, mask, NULL);
+ err = generic_permission(inode, mask, flags, NULL);
return err;
}
diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index 7f01728..4553d88 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -665,7 +665,7 @@
extern void ceph_queue_writeback(struct inode *inode);
extern int ceph_do_getattr(struct inode *inode, int mask);
-extern int ceph_permission(struct inode *inode, int mask);
+extern int ceph_permission(struct inode *inode, int mask, unsigned int flags);
extern int ceph_setattr(struct dentry *dentry, struct iattr *attr);
extern int ceph_getattr(struct vfsmount *mnt, struct dentry *dentry,
struct kstat *stat);
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index 223717d..8e21e0f 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -283,10 +283,13 @@
return 0;
}
-static int cifs_permission(struct inode *inode, int mask)
+static int cifs_permission(struct inode *inode, int mask, unsigned int flags)
{
struct cifs_sb_info *cifs_sb;
+ if (flags & IPERM_FLAG_RCU)
+ return -ECHILD;
+
cifs_sb = CIFS_SB(inode->i_sb);
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_PERM) {
@@ -298,7 +301,7 @@
on the client (above and beyond ACL on servers) for
servers which do not support setting and viewing mode bits,
so allowing client to check permissions is useful */
- return generic_permission(inode, mask, NULL);
+ return generic_permission(inode, mask, flags, NULL);
}
static struct kmem_cache *cifs_inode_cachep;
diff --git a/fs/coda/dir.c b/fs/coda/dir.c
index 619a830..29badd9 100644
--- a/fs/coda/dir.c
+++ b/fs/coda/dir.c
@@ -135,10 +135,13 @@
}
-int coda_permission(struct inode *inode, int mask)
+int coda_permission(struct inode *inode, int mask, unsigned int flags)
{
int error;
+ if (flags & IPERM_FLAG_RCU)
+ return -ECHILD;
+
mask &= MAY_READ | MAY_WRITE | MAY_EXEC;
if (!mask)
diff --git a/fs/coda/pioctl.c b/fs/coda/pioctl.c
index 2fd89b5..741f0bd 100644
--- a/fs/coda/pioctl.c
+++ b/fs/coda/pioctl.c
@@ -24,7 +24,7 @@
#include <linux/coda_psdev.h>
/* pioctl ops */
-static int coda_ioctl_permission(struct inode *inode, int mask);
+static int coda_ioctl_permission(struct inode *inode, int mask, unsigned int flags);
static long coda_pioctl(struct file *filp, unsigned int cmd,
unsigned long user_data);
@@ -41,8 +41,10 @@
};
/* the coda pioctl inode ops */
-static int coda_ioctl_permission(struct inode *inode, int mask)
+static int coda_ioctl_permission(struct inode *inode, int mask, unsigned int flags)
{
+ if (flags & IPERM_FLAG_RCU)
+ return -ECHILD;
return (mask & MAY_EXEC) ? -EACCES : 0;
}
diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c
index f91b35d..337352a 100644
--- a/fs/ecryptfs/inode.c
+++ b/fs/ecryptfs/inode.c
@@ -980,8 +980,10 @@
}
static int
-ecryptfs_permission(struct inode *inode, int mask)
+ecryptfs_permission(struct inode *inode, int mask, unsigned int flags)
{
+ if (flags & IPERM_FLAG_RCU)
+ return -ECHILD;
return inode_permission(ecryptfs_inode_to_lower(inode), mask);
}
diff --git a/fs/ext2/acl.c b/fs/ext2/acl.c
index 2bcc043..dd9bb3f 100644
--- a/fs/ext2/acl.c
+++ b/fs/ext2/acl.c
@@ -232,10 +232,14 @@
}
int
-ext2_check_acl(struct inode *inode, int mask)
+ext2_check_acl(struct inode *inode, int mask, unsigned int flags)
{
- struct posix_acl *acl = ext2_get_acl(inode, ACL_TYPE_ACCESS);
+ struct posix_acl *acl;
+ if (flags & IPERM_FLAG_RCU)
+ return -ECHILD;
+
+ acl = ext2_get_acl(inode, ACL_TYPE_ACCESS);
if (IS_ERR(acl))
return PTR_ERR(acl);
if (acl) {
diff --git a/fs/ext2/acl.h b/fs/ext2/acl.h
index 3ff6cbb..c939b7b 100644
--- a/fs/ext2/acl.h
+++ b/fs/ext2/acl.h
@@ -54,7 +54,7 @@
#ifdef CONFIG_EXT2_FS_POSIX_ACL
/* acl.c */
-extern int ext2_check_acl (struct inode *, int);
+extern int ext2_check_acl (struct inode *, int, unsigned int);
extern int ext2_acl_chmod (struct inode *);
extern int ext2_init_acl (struct inode *, struct inode *);
diff --git a/fs/ext3/acl.c b/fs/ext3/acl.c
index 8a11fe2..9e49da8 100644
--- a/fs/ext3/acl.c
+++ b/fs/ext3/acl.c
@@ -240,10 +240,14 @@
}
int
-ext3_check_acl(struct inode *inode, int mask)
+ext3_check_acl(struct inode *inode, int mask, unsigned int flags)
{
- struct posix_acl *acl = ext3_get_acl(inode, ACL_TYPE_ACCESS);
+ struct posix_acl *acl;
+ if (flags & IPERM_FLAG_RCU)
+ return -ECHILD;
+
+ acl = ext3_get_acl(inode, ACL_TYPE_ACCESS);
if (IS_ERR(acl))
return PTR_ERR(acl);
if (acl) {
diff --git a/fs/ext3/acl.h b/fs/ext3/acl.h
index 5973346..5faf804 100644
--- a/fs/ext3/acl.h
+++ b/fs/ext3/acl.h
@@ -54,7 +54,7 @@
#ifdef CONFIG_EXT3_FS_POSIX_ACL
/* acl.c */
-extern int ext3_check_acl (struct inode *, int);
+extern int ext3_check_acl (struct inode *, int, unsigned int);
extern int ext3_acl_chmod (struct inode *);
extern int ext3_init_acl (handle_t *, struct inode *, struct inode *);
diff --git a/fs/ext4/acl.c b/fs/ext4/acl.c
index 5e2ed45..373dcae 100644
--- a/fs/ext4/acl.c
+++ b/fs/ext4/acl.c
@@ -238,10 +238,14 @@
}
int
-ext4_check_acl(struct inode *inode, int mask)
+ext4_check_acl(struct inode *inode, int mask, unsigned int flags)
{
- struct posix_acl *acl = ext4_get_acl(inode, ACL_TYPE_ACCESS);
+ struct posix_acl *acl;
+ if (flags & IPERM_FLAG_RCU)
+ return -ECHILD;
+
+ acl = ext4_get_acl(inode, ACL_TYPE_ACCESS);
if (IS_ERR(acl))
return PTR_ERR(acl);
if (acl) {
diff --git a/fs/ext4/acl.h b/fs/ext4/acl.h
index 9d843d5..dec8211 100644
--- a/fs/ext4/acl.h
+++ b/fs/ext4/acl.h
@@ -54,7 +54,7 @@
#ifdef CONFIG_EXT4_FS_POSIX_ACL
/* acl.c */
-extern int ext4_check_acl(struct inode *, int);
+extern int ext4_check_acl(struct inode *, int, unsigned int);
extern int ext4_acl_chmod(struct inode *);
extern int ext4_init_acl(handle_t *, struct inode *, struct inode *);
diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c
index 07f4b5e..f738599 100644
--- a/fs/fuse/dir.c
+++ b/fs/fuse/dir.c
@@ -985,12 +985,15 @@
* access request is sent. Execute permission is still checked
* locally based on file mode.
*/
-static int fuse_permission(struct inode *inode, int mask)
+static int fuse_permission(struct inode *inode, int mask, unsigned int flags)
{
struct fuse_conn *fc = get_fuse_conn(inode);
bool refreshed = false;
int err = 0;
+ if (flags & IPERM_FLAG_RCU)
+ return -ECHILD;
+
if (!fuse_allow_task(fc, current))
return -EACCES;
@@ -1005,7 +1008,7 @@
}
if (fc->flags & FUSE_DEFAULT_PERMISSIONS) {
- err = generic_permission(inode, mask, NULL);
+ err = generic_permission(inode, mask, flags, NULL);
/* If permission is denied, try to refresh file
attributes. This is also needed, because the root
@@ -1013,7 +1016,8 @@
if (err == -EACCES && !refreshed) {
err = fuse_do_getattr(inode, NULL, NULL);
if (!err)
- err = generic_permission(inode, mask, NULL);
+ err = generic_permission(inode, mask,
+ flags, NULL);
}
/* Note: the opposite of the above test does not
diff --git a/fs/generic_acl.c b/fs/generic_acl.c
index 6bc9e3a..6280042 100644
--- a/fs/generic_acl.c
+++ b/fs/generic_acl.c
@@ -190,10 +190,14 @@
}
int
-generic_check_acl(struct inode *inode, int mask)
+generic_check_acl(struct inode *inode, int mask, unsigned int flags)
{
- struct posix_acl *acl = get_cached_acl(inode, ACL_TYPE_ACCESS);
+ struct posix_acl *acl;
+ if (flags & IPERM_FLAG_RCU)
+ return -ECHILD;
+
+ acl = get_cached_acl(inode, ACL_TYPE_ACCESS);
if (acl) {
int error = posix_acl_permission(inode, acl, mask);
posix_acl_release(acl);
diff --git a/fs/gfs2/acl.c b/fs/gfs2/acl.c
index 48171f4..7118f1a 100644
--- a/fs/gfs2/acl.c
+++ b/fs/gfs2/acl.c
@@ -75,11 +75,14 @@
* Returns: errno
*/
-int gfs2_check_acl(struct inode *inode, int mask)
+int gfs2_check_acl(struct inode *inode, int mask, unsigned int flags)
{
struct posix_acl *acl;
int error;
+ if (flags & IPERM_FLAG_RCU)
+ return -ECHILD;
+
acl = gfs2_acl_get(GFS2_I(inode), ACL_TYPE_ACCESS);
if (IS_ERR(acl))
return PTR_ERR(acl);
diff --git a/fs/gfs2/acl.h b/fs/gfs2/acl.h
index b522b0c..a93907c 100644
--- a/fs/gfs2/acl.h
+++ b/fs/gfs2/acl.h
@@ -16,7 +16,7 @@
#define GFS2_POSIX_ACL_DEFAULT "posix_acl_default"
#define GFS2_ACL_MAX_ENTRIES 25
-extern int gfs2_check_acl(struct inode *inode, int mask);
+extern int gfs2_check_acl(struct inode *inode, int mask, unsigned int);
extern int gfs2_acl_create(struct gfs2_inode *dip, struct inode *inode);
extern int gfs2_acl_chmod(struct gfs2_inode *ip, struct iattr *attr);
extern const struct xattr_handler gfs2_xattr_system_handler;
diff --git a/fs/gfs2/file.c b/fs/gfs2/file.c
index aa99647..fca6689 100644
--- a/fs/gfs2/file.c
+++ b/fs/gfs2/file.c
@@ -241,7 +241,7 @@
!capable(CAP_LINUX_IMMUTABLE))
goto out;
if (!IS_IMMUTABLE(inode)) {
- error = gfs2_permission(inode, MAY_WRITE);
+ error = gfs2_permission(inode, MAY_WRITE, 0);
if (error)
goto out;
}
diff --git a/fs/gfs2/inode.c b/fs/gfs2/inode.c
index e1213f7..6163be9 100644
--- a/fs/gfs2/inode.c
+++ b/fs/gfs2/inode.c
@@ -509,7 +509,7 @@
}
if (!is_root) {
- error = gfs2_permission(dir, MAY_EXEC);
+ error = gfs2_permission(dir, MAY_EXEC, 0);
if (error)
goto out;
}
@@ -539,7 +539,7 @@
{
int error;
- error = gfs2_permission(&dip->i_inode, MAY_WRITE | MAY_EXEC);
+ error = gfs2_permission(&dip->i_inode, MAY_WRITE | MAY_EXEC, 0);
if (error)
return error;
diff --git a/fs/gfs2/inode.h b/fs/gfs2/inode.h
index d8499fa..732a183 100644
--- a/fs/gfs2/inode.h
+++ b/fs/gfs2/inode.h
@@ -113,7 +113,7 @@
extern struct inode *gfs2_createi(struct gfs2_holder *ghs,
const struct qstr *name,
unsigned int mode, dev_t dev);
-extern int gfs2_permission(struct inode *inode, int mask);
+extern int gfs2_permission(struct inode *inode, int mask, unsigned int flags);
extern int gfs2_setattr_simple(struct gfs2_inode *ip, struct iattr *attr);
extern struct inode *gfs2_lookup_simple(struct inode *dip, const char *name);
extern void gfs2_dinode_out(const struct gfs2_inode *ip, void *buf);
diff --git a/fs/gfs2/ops_inode.c b/fs/gfs2/ops_inode.c
index f28f897..5c63a06 100644
--- a/fs/gfs2/ops_inode.c
+++ b/fs/gfs2/ops_inode.c
@@ -166,7 +166,7 @@
if (error)
goto out_child;
- error = gfs2_permission(dir, MAY_WRITE | MAY_EXEC);
+ error = gfs2_permission(dir, MAY_WRITE | MAY_EXEC, 0);
if (error)
goto out_gunlock;
@@ -289,7 +289,7 @@
if (IS_APPEND(&dip->i_inode))
return -EPERM;
- error = gfs2_permission(&dip->i_inode, MAY_WRITE | MAY_EXEC);
+ error = gfs2_permission(&dip->i_inode, MAY_WRITE | MAY_EXEC, 0);
if (error)
return error;
@@ -822,7 +822,7 @@
}
}
} else {
- error = gfs2_permission(ndir, MAY_WRITE | MAY_EXEC);
+ error = gfs2_permission(ndir, MAY_WRITE | MAY_EXEC, 0);
if (error)
goto out_gunlock;
@@ -857,7 +857,7 @@
/* Check out the dir to be renamed */
if (dir_rename) {
- error = gfs2_permission(odentry->d_inode, MAY_WRITE);
+ error = gfs2_permission(odentry->d_inode, MAY_WRITE, 0);
if (error)
goto out_gunlock;
}
@@ -1041,13 +1041,17 @@
* Returns: errno
*/
-int gfs2_permission(struct inode *inode, int mask)
+int gfs2_permission(struct inode *inode, int mask, unsigned int flags)
{
- struct gfs2_inode *ip = GFS2_I(inode);
+ struct gfs2_inode *ip;
struct gfs2_holder i_gh;
int error;
int unlock = 0;
+ if (flags & IPERM_FLAG_RCU)
+ return -ECHILD;
+
+ ip = GFS2_I(inode);
if (gfs2_glock_is_locked_by_me(ip->i_gl) == NULL) {
error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &i_gh);
if (error)
@@ -1058,7 +1062,7 @@
if ((mask & MAY_WRITE) && IS_IMMUTABLE(inode))
error = -EACCES;
else
- error = generic_permission(inode, mask, gfs2_check_acl);
+ error = generic_permission(inode, mask, flags, gfs2_check_acl);
if (unlock)
gfs2_glock_dq_uninit(&i_gh);
diff --git a/fs/hostfs/hostfs_kern.c b/fs/hostfs/hostfs_kern.c
index 0bc81cf..d3244d9 100644
--- a/fs/hostfs/hostfs_kern.c
+++ b/fs/hostfs/hostfs_kern.c
@@ -749,11 +749,14 @@
return err;
}
-int hostfs_permission(struct inode *ino, int desired)
+int hostfs_permission(struct inode *ino, int desired, unsigned int flags)
{
char *name;
int r = 0, w = 0, x = 0, err;
+ if (flags & IPERM_FLAG_RCU)
+ return -ECHILD;
+
if (desired & MAY_READ) r = 1;
if (desired & MAY_WRITE) w = 1;
if (desired & MAY_EXEC) x = 1;
@@ -768,7 +771,7 @@
err = access_file(name, r, w, x);
__putname(name);
if (!err)
- err = generic_permission(ino, desired, NULL);
+ err = generic_permission(ino, desired, flags, NULL);
return err;
}
diff --git a/fs/hpfs/namei.c b/fs/hpfs/namei.c
index 11c2b40..f4ad9e3 100644
--- a/fs/hpfs/namei.c
+++ b/fs/hpfs/namei.c
@@ -419,7 +419,7 @@
unlock_kernel();
return -ENOSPC;
}
- if (generic_permission(inode, MAY_WRITE, NULL) ||
+ if (generic_permission(inode, MAY_WRITE, 0, NULL) ||
!S_ISREG(inode->i_mode) ||
get_write_access(inode)) {
d_rehash(dentry);
diff --git a/fs/jffs2/acl.c b/fs/jffs2/acl.c
index 54a92fd..95b7967 100644
--- a/fs/jffs2/acl.c
+++ b/fs/jffs2/acl.c
@@ -259,11 +259,14 @@
return rc;
}
-int jffs2_check_acl(struct inode *inode, int mask)
+int jffs2_check_acl(struct inode *inode, int mask, unsigned int flags)
{
struct posix_acl *acl;
int rc;
+ if (flags & IPERM_FLAG_RCU)
+ return -ECHILD;
+
acl = jffs2_get_acl(inode, ACL_TYPE_ACCESS);
if (IS_ERR(acl))
return PTR_ERR(acl);
diff --git a/fs/jffs2/acl.h b/fs/jffs2/acl.h
index 5e42de8..3119f59 100644
--- a/fs/jffs2/acl.h
+++ b/fs/jffs2/acl.h
@@ -26,7 +26,7 @@
#ifdef CONFIG_JFFS2_FS_POSIX_ACL
-extern int jffs2_check_acl(struct inode *, int);
+extern int jffs2_check_acl(struct inode *, int, unsigned int);
extern int jffs2_acl_chmod(struct inode *);
extern int jffs2_init_acl_pre(struct inode *, struct inode *, int *);
extern int jffs2_init_acl_post(struct inode *);
diff --git a/fs/jfs/acl.c b/fs/jfs/acl.c
index 1057a49..e5de942 100644
--- a/fs/jfs/acl.c
+++ b/fs/jfs/acl.c
@@ -114,10 +114,14 @@
return rc;
}
-int jfs_check_acl(struct inode *inode, int mask)
+int jfs_check_acl(struct inode *inode, int mask, unsigned int flags)
{
- struct posix_acl *acl = jfs_get_acl(inode, ACL_TYPE_ACCESS);
+ struct posix_acl *acl;
+ if (flags & IPERM_FLAG_RCU)
+ return -ECHILD;
+
+ acl = jfs_get_acl(inode, ACL_TYPE_ACCESS);
if (IS_ERR(acl))
return PTR_ERR(acl);
if (acl) {
diff --git a/fs/jfs/jfs_acl.h b/fs/jfs/jfs_acl.h
index 54e0755..f9285c4 100644
--- a/fs/jfs/jfs_acl.h
+++ b/fs/jfs/jfs_acl.h
@@ -20,7 +20,7 @@
#ifdef CONFIG_JFS_POSIX_ACL
-int jfs_check_acl(struct inode *, int);
+int jfs_check_acl(struct inode *, int, unsigned int flags);
int jfs_init_acl(tid_t, struct inode *, struct inode *);
int jfs_acl_chmod(struct inode *inode);
diff --git a/fs/logfs/dir.c b/fs/logfs/dir.c
index 409dfd6..f9ddf0c 100644
--- a/fs/logfs/dir.c
+++ b/fs/logfs/dir.c
@@ -555,9 +555,11 @@
return __logfs_create(dir, dentry, inode, target, destlen);
}
-static int logfs_permission(struct inode *inode, int mask)
+static int logfs_permission(struct inode *inode, int mask, unsigned int flags)
{
- return generic_permission(inode, mask, NULL);
+ if (flags & IPERM_FLAG_RCU)
+ return -ECHILD;
+ return generic_permission(inode, mask, flags, NULL);
}
static int logfs_link(struct dentry *old_dentry, struct inode *dir,
diff --git a/fs/namei.c b/fs/namei.c
index 6e27536..4e957bf 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -169,8 +169,8 @@
/*
* This does basic POSIX ACL permission checking
*/
-static inline int __acl_permission_check(struct inode *inode, int mask,
- int (*check_acl)(struct inode *inode, int mask), int rcu)
+static int acl_permission_check(struct inode *inode, int mask, unsigned int flags,
+ int (*check_acl)(struct inode *inode, int mask, unsigned int flags))
{
umode_t mode = inode->i_mode;
@@ -180,13 +180,9 @@
mode >>= 6;
else {
if (IS_POSIXACL(inode) && (mode & S_IRWXG) && check_acl) {
- if (rcu) {
- return -ECHILD;
- } else {
- int error = check_acl(inode, mask);
- if (error != -EAGAIN)
- return error;
- }
+ int error = check_acl(inode, mask, flags);
+ if (error != -EAGAIN)
+ return error;
}
if (in_group_p(inode->i_gid))
@@ -201,32 +197,31 @@
return -EACCES;
}
-static inline int acl_permission_check(struct inode *inode, int mask,
- int (*check_acl)(struct inode *inode, int mask))
-{
- return __acl_permission_check(inode, mask, check_acl, 0);
-}
-
/**
- * generic_permission - check for access rights on a Posix-like filesystem
+ * generic_permission - check for access rights on a Posix-like filesystem
* @inode: inode to check access rights for
* @mask: right to check for (%MAY_READ, %MAY_WRITE, %MAY_EXEC)
* @check_acl: optional callback to check for Posix ACLs
+ * @flags IPERM_FLAG_ flags.
*
* Used to check for read/write/execute permissions on a file.
* We use "fsuid" for this, letting us set arbitrary permissions
* for filesystem access without changing the "normal" uids which
- * are used for other things..
+ * are used for other things.
+ *
+ * generic_permission is rcu-walk aware. It returns -ECHILD in case an rcu-walk
+ * request cannot be satisfied (eg. requires blocking or too much complexity).
+ * It would then be called again in ref-walk mode.
*/
-int generic_permission(struct inode *inode, int mask,
- int (*check_acl)(struct inode *inode, int mask))
+int generic_permission(struct inode *inode, int mask, unsigned int flags,
+ int (*check_acl)(struct inode *inode, int mask, unsigned int flags))
{
int ret;
/*
* Do the basic POSIX ACL permission checks.
*/
- ret = acl_permission_check(inode, mask, check_acl);
+ ret = acl_permission_check(inode, mask, flags, check_acl);
if (ret != -EACCES)
return ret;
@@ -281,9 +276,10 @@
}
if (inode->i_op->permission)
- retval = inode->i_op->permission(inode, mask);
+ retval = inode->i_op->permission(inode, mask, 0);
else
- retval = generic_permission(inode, mask, inode->i_op->check_acl);
+ retval = generic_permission(inode, mask, 0,
+ inode->i_op->check_acl);
if (retval)
return retval;
@@ -668,22 +664,19 @@
* short-cut DAC fails, then call ->permission() to do more
* complete permission check.
*/
-static inline int __exec_permission(struct inode *inode, int rcu)
+static inline int exec_permission(struct inode *inode, unsigned int flags)
{
int ret;
if (inode->i_op->permission) {
- if (rcu)
- return -ECHILD;
- ret = inode->i_op->permission(inode, MAY_EXEC);
- if (!ret)
- goto ok;
- return ret;
+ ret = inode->i_op->permission(inode, MAY_EXEC, flags);
+ } else {
+ ret = acl_permission_check(inode, MAY_EXEC, flags,
+ inode->i_op->check_acl);
}
- ret = __acl_permission_check(inode, MAY_EXEC, inode->i_op->check_acl, rcu);
- if (!ret)
+ if (likely(!ret))
goto ok;
- if (rcu && ret == -ECHILD)
+ if (ret == -ECHILD)
return ret;
if (capable(CAP_DAC_OVERRIDE) || capable(CAP_DAC_READ_SEARCH))
@@ -691,17 +684,7 @@
return ret;
ok:
- return security_inode_exec_permission(inode, rcu);
-}
-
-static int exec_permission(struct inode *inode)
-{
- return __exec_permission(inode, 0);
-}
-
-static int exec_permission_rcu(struct inode *inode)
-{
- return __exec_permission(inode, 1);
+ return security_inode_exec_permission(inode, flags);
}
static __always_inline void set_root(struct nameidata *nd)
@@ -1165,7 +1148,7 @@
nd->flags |= LOOKUP_CONTINUE;
if (nd->flags & LOOKUP_RCU) {
- err = exec_permission_rcu(nd->inode);
+ err = exec_permission(nd->inode, IPERM_FLAG_RCU);
if (err == -ECHILD) {
if (nameidata_drop_rcu(nd))
return -ECHILD;
@@ -1173,7 +1156,7 @@
}
} else {
exec_again:
- err = exec_permission(nd->inode);
+ err = exec_permission(nd->inode, 0);
}
if (err)
break;
@@ -1620,7 +1603,7 @@
struct dentry *dentry;
int err;
- err = exec_permission(inode);
+ err = exec_permission(inode, 0);
if (err)
return ERR_PTR(err);
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 58beace..d33da53 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -2189,11 +2189,14 @@
return nfs_do_access(inode, cred, nfs_open_permission_mask(openflags));
}
-int nfs_permission(struct inode *inode, int mask)
+int nfs_permission(struct inode *inode, int mask, unsigned int flags)
{
struct rpc_cred *cred;
int res = 0;
+ if (flags & IPERM_FLAG_RCU)
+ return -ECHILD;
+
nfs_inc_stats(inode, NFSIOS_VFSACCESS);
if ((mask & (MAY_READ | MAY_WRITE | MAY_EXEC)) == 0)
@@ -2241,7 +2244,7 @@
out_notsup:
res = nfs_revalidate_inode(NFS_SERVER(inode), inode);
if (res == 0)
- res = generic_permission(inode, mask, NULL);
+ res = generic_permission(inode, mask, flags, NULL);
goto out;
}
diff --git a/fs/nilfs2/inode.c b/fs/nilfs2/inode.c
index 71d4bc8..77b48c8 100644
--- a/fs/nilfs2/inode.c
+++ b/fs/nilfs2/inode.c
@@ -785,15 +785,19 @@
return err;
}
-int nilfs_permission(struct inode *inode, int mask)
+int nilfs_permission(struct inode *inode, int mask, unsigned int flags)
{
- struct nilfs_root *root = NILFS_I(inode)->i_root;
+ struct nilfs_root *root;
+ if (flags & IPERM_FLAG_RCU)
+ return -ECHILD;
+
+ root = NILFS_I(inode)->i_root;
if ((mask & MAY_WRITE) && root &&
root->cno != NILFS_CPTREE_CURRENT_CNO)
return -EROFS; /* snapshot is not writable */
- return generic_permission(inode, mask, NULL);
+ return generic_permission(inode, mask, flags, NULL);
}
int nilfs_load_inode_block(struct nilfs_sb_info *sbi, struct inode *inode,
diff --git a/fs/nilfs2/nilfs.h b/fs/nilfs2/nilfs.h
index f7560da..0ca9882 100644
--- a/fs/nilfs2/nilfs.h
+++ b/fs/nilfs2/nilfs.h
@@ -256,7 +256,7 @@
extern void nilfs_truncate(struct inode *);
extern void nilfs_evict_inode(struct inode *);
extern int nilfs_setattr(struct dentry *, struct iattr *);
-int nilfs_permission(struct inode *inode, int mask);
+int nilfs_permission(struct inode *inode, int mask, unsigned int flags);
extern int nilfs_load_inode_block(struct nilfs_sb_info *, struct inode *,
struct buffer_head **);
extern int nilfs_inode_dirty(struct inode *);
diff --git a/fs/ocfs2/acl.c b/fs/ocfs2/acl.c
index 3919150..704f6b1 100644
--- a/fs/ocfs2/acl.c
+++ b/fs/ocfs2/acl.c
@@ -291,13 +291,17 @@
return ret;
}
-int ocfs2_check_acl(struct inode *inode, int mask)
+int ocfs2_check_acl(struct inode *inode, int mask, unsigned int flags)
{
- struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+ struct ocfs2_super *osb;
struct buffer_head *di_bh = NULL;
struct posix_acl *acl;
int ret = -EAGAIN;
+ if (flags & IPERM_FLAG_RCU)
+ return -ECHILD;
+
+ osb = OCFS2_SB(inode->i_sb);
if (!(osb->s_mount_opt & OCFS2_MOUNT_POSIX_ACL))
return ret;
diff --git a/fs/ocfs2/acl.h b/fs/ocfs2/acl.h
index 5c5d31f..4fe7c9c 100644
--- a/fs/ocfs2/acl.h
+++ b/fs/ocfs2/acl.h
@@ -26,7 +26,7 @@
__le32 e_id;
};
-extern int ocfs2_check_acl(struct inode *, int);
+extern int ocfs2_check_acl(struct inode *, int, unsigned int);
extern int ocfs2_acl_chmod(struct inode *);
extern int ocfs2_init_acl(handle_t *, struct inode *, struct inode *,
struct buffer_head *, struct buffer_head *,
diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index f6cba56..bdadbae0 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -1307,10 +1307,13 @@
return err;
}
-int ocfs2_permission(struct inode *inode, int mask)
+int ocfs2_permission(struct inode *inode, int mask, unsigned int flags)
{
int ret;
+ if (flags & IPERM_FLAG_RCU)
+ return -ECHILD;
+
mlog_entry_void();
ret = ocfs2_inode_lock(inode, NULL, 0);
@@ -1320,7 +1323,7 @@
goto out;
}
- ret = generic_permission(inode, mask, ocfs2_check_acl);
+ ret = generic_permission(inode, mask, flags, ocfs2_check_acl);
ocfs2_inode_unlock(inode, 0);
out:
diff --git a/fs/ocfs2/file.h b/fs/ocfs2/file.h
index 97bf761..f5afbbe 100644
--- a/fs/ocfs2/file.h
+++ b/fs/ocfs2/file.h
@@ -61,7 +61,7 @@
int ocfs2_setattr(struct dentry *dentry, struct iattr *attr);
int ocfs2_getattr(struct vfsmount *mnt, struct dentry *dentry,
struct kstat *stat);
-int ocfs2_permission(struct inode *inode, int mask);
+int ocfs2_permission(struct inode *inode, int mask, unsigned int flags);
int ocfs2_should_update_atime(struct inode *inode,
struct vfsmount *vfsmnt);
diff --git a/fs/proc/base.c b/fs/proc/base.c
index dc5b2fc..b953d41 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -2114,11 +2114,13 @@
* /proc/pid/fd needs a special permission handler so that a process can still
* access /proc/self/fd after it has executed a setuid().
*/
-static int proc_fd_permission(struct inode *inode, int mask)
+static int proc_fd_permission(struct inode *inode, int mask, unsigned int flags)
{
int rv;
- rv = generic_permission(inode, mask, NULL);
+ if (flags & IPERM_FLAG_RCU)
+ return -ECHILD;
+ rv = generic_permission(inode, mask, flags, NULL);
if (rv == 0)
return 0;
if (task_pid(current) == proc_pid(inode))
diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c
index c9097f4..09a1f92 100644
--- a/fs/proc/proc_sysctl.c
+++ b/fs/proc/proc_sysctl.c
@@ -295,7 +295,7 @@
return ret;
}
-static int proc_sys_permission(struct inode *inode, int mask)
+static int proc_sys_permission(struct inode *inode, int mask,unsigned int flags)
{
/*
* sysctl entries that are not writeable,
@@ -305,6 +305,9 @@
struct ctl_table *table;
int error;
+ if (flags & IPERM_FLAG_RCU)
+ return -ECHILD;
+
/* Executable files are not allowed under /proc/sys/ */
if ((mask & MAY_EXEC) && S_ISREG(inode->i_mode))
return -EACCES;
diff --git a/fs/reiserfs/xattr.c b/fs/reiserfs/xattr.c
index 9ea22a5..3cfb2e9 100644
--- a/fs/reiserfs/xattr.c
+++ b/fs/reiserfs/xattr.c
@@ -870,11 +870,14 @@
return err;
}
-static int reiserfs_check_acl(struct inode *inode, int mask)
+static int reiserfs_check_acl(struct inode *inode, int mask, unsigned int flags)
{
struct posix_acl *acl;
int error = -EAGAIN; /* do regular unix permission checks by default */
+ if (flags & IPERM_FLAG_RCU)
+ return -ECHILD;
+
acl = reiserfs_get_acl(inode, ACL_TYPE_ACCESS);
if (acl) {
@@ -951,8 +954,10 @@
return 0;
}
-int reiserfs_permission(struct inode *inode, int mask)
+int reiserfs_permission(struct inode *inode, int mask, unsigned int flags)
{
+ if (flags & IPERM_FLAG_RCU)
+ return -ECHILD;
/*
* We don't do permission checks on the internal objects.
* Permissions are determined by the "owning" object.
@@ -965,9 +970,10 @@
* Stat data v1 doesn't support ACLs.
*/
if (get_inode_sd_version(inode) != STAT_DATA_V1)
- return generic_permission(inode, mask, reiserfs_check_acl);
+ return generic_permission(inode, mask, flags,
+ reiserfs_check_acl);
#endif
- return generic_permission(inode, mask, NULL);
+ return generic_permission(inode, mask, flags, NULL);
}
static int xattr_hide_revalidate(struct dentry *dentry, struct nameidata *nd)
diff --git a/fs/sysfs/inode.c b/fs/sysfs/inode.c
index cffb1fd..30ac273 100644
--- a/fs/sysfs/inode.c
+++ b/fs/sysfs/inode.c
@@ -348,13 +348,18 @@
return -ENOENT;
}
-int sysfs_permission(struct inode *inode, int mask)
+int sysfs_permission(struct inode *inode, int mask, unsigned int flags)
{
- struct sysfs_dirent *sd = inode->i_private;
+ struct sysfs_dirent *sd;
+
+ if (flags & IPERM_FLAG_RCU)
+ return -ECHILD;
+
+ sd = inode->i_private;
mutex_lock(&sysfs_mutex);
sysfs_refresh_inode(sd, inode);
mutex_unlock(&sysfs_mutex);
- return generic_permission(inode, mask, NULL);
+ return generic_permission(inode, mask, flags, NULL);
}
diff --git a/fs/sysfs/sysfs.h b/fs/sysfs/sysfs.h
index d9be60a..ffaaa81 100644
--- a/fs/sysfs/sysfs.h
+++ b/fs/sysfs/sysfs.h
@@ -200,7 +200,7 @@
struct inode *sysfs_get_inode(struct super_block *sb, struct sysfs_dirent *sd);
void sysfs_evict_inode(struct inode *inode);
int sysfs_sd_setattr(struct sysfs_dirent *sd, struct iattr *iattr);
-int sysfs_permission(struct inode *inode, int mask);
+int sysfs_permission(struct inode *inode, int mask, unsigned int flags);
int sysfs_setattr(struct dentry *dentry, struct iattr *iattr);
int sysfs_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat);
int sysfs_setxattr(struct dentry *dentry, const char *name, const void *value,
diff --git a/fs/xfs/linux-2.6/xfs_acl.c b/fs/xfs/linux-2.6/xfs_acl.c
index b277186..4b11eaf 100644
--- a/fs/xfs/linux-2.6/xfs_acl.c
+++ b/fs/xfs/linux-2.6/xfs_acl.c
@@ -219,12 +219,16 @@
}
int
-xfs_check_acl(struct inode *inode, int mask)
+xfs_check_acl(struct inode *inode, int mask, unsigned int flags)
{
- struct xfs_inode *ip = XFS_I(inode);
+ struct xfs_inode *ip;
struct posix_acl *acl;
int error = -EAGAIN;
+ if (flags & IPERM_FLAG_RCU)
+ return -ECHILD;
+
+ ip = XFS_I(inode);
trace_xfs_check_acl(ip);
/*
diff --git a/fs/xfs/xfs_acl.h b/fs/xfs/xfs_acl.h
index 0135e2a..11dd720 100644
--- a/fs/xfs/xfs_acl.h
+++ b/fs/xfs/xfs_acl.h
@@ -42,7 +42,7 @@
#define SGI_ACL_DEFAULT_SIZE (sizeof(SGI_ACL_DEFAULT)-1)
#ifdef CONFIG_XFS_POSIX_ACL
-extern int xfs_check_acl(struct inode *inode, int mask);
+extern int xfs_check_acl(struct inode *inode, int mask, unsigned int flags);
extern struct posix_acl *xfs_get_acl(struct inode *inode, int type);
extern int xfs_inherit_acl(struct inode *inode, struct posix_acl *default_acl);
extern int xfs_acl_chmod(struct inode *inode);
diff --git a/include/linux/coda_linux.h b/include/linux/coda_linux.h
index 2e914d0..4ccc59c 100644
--- a/include/linux/coda_linux.h
+++ b/include/linux/coda_linux.h
@@ -37,7 +37,7 @@
/* operations shared over more than one file */
int coda_open(struct inode *i, struct file *f);
int coda_release(struct inode *i, struct file *f);
-int coda_permission(struct inode *inode, int mask);
+int coda_permission(struct inode *inode, int mask, unsigned int flags);
int coda_revalidate_inode(struct dentry *);
int coda_getattr(struct vfsmount *, struct dentry *, struct kstat *);
int coda_setattr(struct dentry *, struct iattr *);
diff --git a/include/linux/fs.h b/include/linux/fs.h
index a04aa96..d5a4d42 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1550,11 +1550,13 @@
int (*setlease)(struct file *, long, struct file_lock **);
};
+#define IPERM_FLAG_RCU 0x0001
+
struct inode_operations {
struct dentry * (*lookup) (struct inode *,struct dentry *, struct nameidata *);
void * (*follow_link) (struct dentry *, struct nameidata *);
- int (*permission) (struct inode *, int);
- int (*check_acl)(struct inode *, int);
+ int (*permission) (struct inode *, int, unsigned int);
+ int (*check_acl)(struct inode *, int, unsigned int);
int (*readlink) (struct dentry *, char __user *,int);
void (*put_link) (struct dentry *, struct nameidata *, void *);
@@ -2165,8 +2167,8 @@
#endif
extern int notify_change(struct dentry *, struct iattr *);
extern int inode_permission(struct inode *, int);
-extern int generic_permission(struct inode *, int,
- int (*check_acl)(struct inode *, int));
+extern int generic_permission(struct inode *, int, unsigned int,
+ int (*check_acl)(struct inode *, int, unsigned int));
static inline bool execute_ok(struct inode *inode)
{
diff --git a/include/linux/generic_acl.h b/include/linux/generic_acl.h
index 574bea4..0437e37 100644
--- a/include/linux/generic_acl.h
+++ b/include/linux/generic_acl.h
@@ -10,6 +10,6 @@
int generic_acl_init(struct inode *, struct inode *);
int generic_acl_chmod(struct inode *);
-int generic_check_acl(struct inode *inode, int mask);
+int generic_check_acl(struct inode *inode, int mask, unsigned int flags);
#endif /* LINUX_GENERIC_ACL_H */
diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h
index 29d504d..0779bb8 100644
--- a/include/linux/nfs_fs.h
+++ b/include/linux/nfs_fs.h
@@ -351,7 +351,7 @@
extern int nfs_post_op_update_inode(struct inode *inode, struct nfs_fattr *fattr);
extern int nfs_post_op_update_inode_force_wcc(struct inode *inode, struct nfs_fattr *fattr);
extern int nfs_getattr(struct vfsmount *, struct dentry *, struct kstat *);
-extern int nfs_permission(struct inode *, int);
+extern int nfs_permission(struct inode *, int, unsigned int);
extern int nfs_open(struct inode *, struct file *);
extern int nfs_release(struct inode *, struct file *);
extern int nfs_attribute_timeout(struct inode *inode);
diff --git a/include/linux/reiserfs_xattr.h b/include/linux/reiserfs_xattr.h
index b2cf208..3b94c91 100644
--- a/include/linux/reiserfs_xattr.h
+++ b/include/linux/reiserfs_xattr.h
@@ -41,7 +41,7 @@
int reiserfs_lookup_privroot(struct super_block *sb);
int reiserfs_delete_xattrs(struct inode *inode);
int reiserfs_chown_xattrs(struct inode *inode, struct iattr *attrs);
-int reiserfs_permission(struct inode *inode, int mask);
+int reiserfs_permission(struct inode *inode, int mask, unsigned int flags);
#ifdef CONFIG_REISERFS_FS_XATTR
#define has_xattr_dir(inode) (REISERFS_I(inode)->i_flags & i_has_xattr_dir)