[PATCH v5 3/7] CIFS: Add O_DENY* open flags support

Pavel Shilovsky
2013-04-09T12:36:38Z

Construct share_access value from O_DENY* flags and send it to
the server.

Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
---
fs/cifs/cifsfs.c | 2 +-
fs/cifs/cifsglob.h | 16 +++++++++++++++-
fs/cifs/dir.c | 3 +++
fs/cifs/file.c | 4 ++++
fs/locks.c | 7 ++++++-
include/linux/fs.h | 1 +
6 files changed, 30 insertions(+), 3 deletions(-)

diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index e328339..469dffb 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -769,7 +769,7 @@ struct file_system_type cifs_fs_type = {
.name = "cifs",
.mount = cifs_do_mount,
.kill_sb = cifs_kill_sb,
- /* .fs_flags */
+ .fs_flags = FS_DOES_SHARELOCK,
};
const struct inode_operations cifs_dir_inode_ops = {
.create = cifs_create,
diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index cd4bbf3..7e876b9 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -465,7 +465,7 @@ struct smb_vol {
CIFS_MOUNT_CIFS_BACKUPUID | CIFS_MOUNT_CIFS_BACKUPGID)

#define CIFS_MS_MASK (MS_RDONLY | MS_MANDLOCK | MS_NOEXEC | MS_NOSUID | \
- MS_NODEV | MS_SYNCHRONOUS)
+ MS_NODEV | MS_SYNCHRONOUS | MS_SHARELOCK)

struct cifs_mnt_data {
struct cifs_sb_info *cifs_sb;
@@ -947,6 +947,20 @@ struct cifsFileInfo {
struct work_struct oplock_break; /* work for oplock breaks */
};

+static inline int
+cifs_get_share_flags(unsigned int flags)
+{
+ int share_access = 0;
+
+ if (!(flags & O_DENYREAD))
+ share_access |= FILE_SHARE_READ;
+ if (!(flags & O_DENYWRITE))
+ share_access |= FILE_SHARE_WRITE;
+ if (!(flags & O_DENYDELETE))
+ share_access |= FILE_SHARE_DELETE;
+ return share_access;
+}
+
struct cifs_io_parms {
__u16 netfid;
#ifdef CONFIG_CIFS_SMB2
diff --git a/fs/cifs/dir.c b/fs/cifs/dir.c
index 267b608..d4331de 100644
--- a/fs/cifs/dir.c
+++ b/fs/cifs/dir.c
@@ -294,6 +294,9 @@ cifs_do_create(struct inode *inode, struct dentry *direntry, unsigned int xid,
else
cFYI(1, "Create flag not set in create function");

+ if (IS_SHARELOCK(inode))
+ share_access = cifs_get_share_flags(oflags);
+
/*
* BB add processing to set equivalent of mode - e.g. via CreateX with
* ACLs
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index 0d524a7..9394b2b 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -210,6 +210,8 @@ cifs_nt_open(char *full_path, struct inode *inode, struct cifs_sb_info *cifs_sb,
*********************************************************************/

disposition = cifs_get_disposition(f_flags);
+ if (IS_SHARELOCK(inode))
+ share_access = cifs_get_share_flags(f_flags);

/* BB pass O_SYNC flag through on file attributes .. BB */

@@ -645,6 +647,8 @@ cifs_reopen_file(struct cifsFileInfo *cfile, bool can_flush)
}

desired_access = cifs_convert_flags(cfile->f_flags);
+ if (IS_SHARELOCK(inode))
+ share_access = cifs_get_share_flags(cfile->f_flags);

if (backup_cred(cifs_sb))
create_options |= CREATE_OPEN_BACKUP_INTENT;
diff --git a/fs/locks.c b/fs/locks.c
index 1eccc75..52c9ea1 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -846,8 +846,13 @@ deny_lock_file(struct file *filp)
{
struct file_lock *lock;
int error = 0;
+ struct inode *inode = filp->f_path.dentry->d_inode;

- if (!IS_SHARELOCK(filp->f_path.dentry->d_inode))
+ if (!IS_SHARELOCK(inode))
+ return error;
+
+ /* Don't set a lock on file systems that do it internally */
+ if (inode->i_sb->s_type->fs_flags & FS_DOES_SHARELOCK)
return error;

error = flock_make_lock(filp, &lock, deny_flags_to_cmd(filp->f_flags));
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 073e31a..8a4232e 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1816,6 +1816,7 @@ struct file_system_type {
#define FS_USERNS_DEV_MOUNT 16 /* A userns mount does not imply MNT_NODEV */
#define FS_REVAL_DOT 16384 /* Check the paths ".", ".." for staleness */
#define FS_RENAME_DOES_D_MOVE 32768 /* FS will handle d_move() during rename() internally. */
+#define FS_DOES_SHARELOCK 65536 /* FS does sharelocks internally */
struct dentry *(*mount) (struct file_system_type *, int,
const char *, void *);
void (*kill_sb) (struct super_block *);
--
1.8.1.5