The patch titled
do namei_flags calculation inside open_namei()
has been added to the -mm tree. Its filename is
do-namei_flags-calculation-inside-open_namei.patch
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*** Remember to use Documentation/SubmitChecklist when testing your code ***
See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find
out what to do about this
The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/
------------------------------------------------------
Subject: do namei_flags calculation inside open_namei()
From: Dave Hansen <haveblue@xxxxxxxxxx>
My end goal here is to make sure all users of may_open() return filps. This
will ensure that we properly release mount write counts which were taken for
the filp in may_open().
This patch moves the sys_open flags to namei flags calculation into
fs/namei.c. We'll shortly be moving the nameidata_to_filp() calls into
namei.c, and this gets the sys_open flags to a place where we can get at them
when we need them.
Acked-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Dave Hansen <haveblue@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
fs/namei.c | 43 ++++++++++++++++++++++++++++++++++---------
fs/open.c | 22 ++--------------------
2 files changed, 36 insertions(+), 29 deletions(-)
diff -puN fs/namei.c~do-namei_flags-calculation-inside-open_namei fs/namei.c
--- a/fs/namei.c~do-namei_flags-calculation-inside-open_namei
+++ a/fs/namei.c
@@ -1677,7 +1677,12 @@ int may_open(struct nameidata *nd, int a
return 0;
}
-static int open_namei_create(struct nameidata *nd, struct path *path,
+/*
+ * Be careful about ever adding any more callers of this
+ * function. Its flags must be in the namei format, not
+ * what get passed to sys_open().
+ */
+static int __open_namei_create(struct nameidata *nd, struct path *path,
int flag, int mode)
{
int error;
@@ -1696,26 +1701,46 @@ static int open_namei_create(struct name
}
/*
+ * Note that while the flag value (low two bits) for sys_open means:
+ * 00 - read-only
+ * 01 - write-only
+ * 10 - read-write
+ * 11 - special
+ * it is changed into
+ * 00 - no permissions needed
+ * 01 - read-permission
+ * 10 - write-permission
+ * 11 - read-write
+ * for the internal routines (ie open_namei()/follow_link() etc)
+ * This is more logical, and also allows the 00 "no perm needed"
+ * to be used for symlinks (where the permissions are checked
+ * later).
+ *
+*/
+static inline int open_to_namei_flags(int flag)
+{
+ if ((flag+1) & O_ACCMODE)
+ flag++;
+ return flag;
+}
+
+/*
* open_namei()
*
* namei for open - this is in fact almost the whole open-routine.
*
* Note that the low bits of "flag" aren't the same as in the open
- * system call - they are 00 - no permissions needed
- * 01 - read permission needed
- * 10 - write permission needed
- * 11 - read/write permissions needed
- * which is a lot more logical, and also allows the "no perm" needed
- * for symlinks (where the permissions are checked later).
+ * system call. See open_to_namei_flags().
* SMP-safe
*/
-int open_namei(int dfd, const char *pathname, int flag,
+int open_namei(int dfd, const char *pathname, int open_flag,
int mode, struct nameidata *nd)
{
int acc_mode, error;
struct path path;
struct dentry *dir;
int count = 0;
+ int flag = open_to_namei_flags(open_flag);
acc_mode = ACC_MODE(flag);
@@ -1776,7 +1801,7 @@ do_last:
/* Negative dentry, just create the file */
if (!path.dentry->d_inode) {
- error = open_namei_create(nd, &path, flag, mode);
+ error = __open_namei_create(nd, &path, flag, mode);
if (error)
goto exit;
return 0;
diff -puN fs/open.c~do-namei_flags-calculation-inside-open_namei fs/open.c
--- a/fs/open.c~do-namei_flags-calculation-inside-open_namei
+++ a/fs/open.c
@@ -796,31 +796,13 @@ cleanup_file:
return ERR_PTR(error);
}
-/*
- * Note that while the flag value (low two bits) for sys_open means:
- * 00 - read-only
- * 01 - write-only
- * 10 - read-write
- * 11 - special
- * it is changed into
- * 00 - no permissions needed
- * 01 - read-permission
- * 10 - write-permission
- * 11 - read-write
- * for the internal routines (ie open_namei()/follow_link() etc). 00 is
- * used by symlinks.
- */
static struct file *do_filp_open(int dfd, const char *filename, int flags,
int mode)
{
- int namei_flags, error;
+ int error;
struct nameidata nd;
- namei_flags = flags;
- if ((namei_flags+1) & O_ACCMODE)
- namei_flags++;
-
- error = open_namei(dfd, filename, namei_flags, mode, &nd);
+ error = open_namei(dfd, filename, flags, mode, &nd);
if (!error)
return nameidata_to_filp(&nd, flags);
_
Patches currently in -mm which might be from haveblue@xxxxxxxxxx are
enable-hotplug-memory-remove-for-ppc64.patch
reiserfs-eliminate-private-use-of-struct-file-in-xattr.patch
hppfs-pass-vfsmount-to-dentry_open.patch
check-for-null-vfsmount-in-dentry_open.patch
fix-up-new-filp-allocators.patch
do-namei_flags-calculation-inside-open_namei.patch
merge-open_namei-and-do_filp_open.patch
r-o-bind-mounts-stub-functions.patch
r-o-bind-mounts-create-helper-to-drop-file-write-access.patch
r-o-bind-mounts-drop-write-during-emergency-remount.patch
r-o-bind-mounts-elevate-write-count-for-vfs_rmdir.patch
r-o-bind-mounts-elevate-write-count-for-callers-of-vfs_mkdir.patch
r-o-bind-mounts-elevate-mnt_writers-for-unlink-callers.patch
r-o-bind-mounts-elevate-write-count-for-xattr_permission-callers.patch
r-o-bind-mounts-elevate-write-count-for-ncp_ioctl.patch
r-o-bind-mounts-write-counts-for-time-functions.patch
r-o-bind-mounts-elevate-write-count-for-do_utimes.patch
r-o-bind-mounts-write-count-for-file_update_time.patch
r-o-bind-mounts-write-counts-for-link-symlink.patch
r-o-bind-mounts-elevate-write-count-for-ioctls.patch
r-o-bind-mounts-elevate-write-count-for-opens.patch
r-o-bind-mounts-get-write-access-for-vfs_rename-callers.patch
r-o-bind-mounts-elevate-write-count-for-chmod-chown-callers.patch
r-o-bind-mounts-write-counts-for-truncate.patch
r-o-bind-mounts-elevate-count-for-xfs-timestamp-updates.patch
r-o-bind-mounts-make-access-use-new-r-o-helper.patch
r-o-bind-mounts-check-mnt-instead-of-superblock-directly.patch
r-o-bind-mounts-get-callers-of-vfs_mknod-create.patch
r-o-bind-mounts-track-numbers-of-writers-to-mounts.patch
r-o-bind-mounts-honor-mount-writer-counts-at-remount.patch
r-o-bind-mounts-debugging-for-missed-calls.patch
reiser4.patch
page-owner-tracking-leak-detector.patch
-
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