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cifs: fix flags handling in cifs_posix_open
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The way flags are passed and converted for cifs_posix_open is rather
non-sensical. Some callers call cifs_posix_convert_flags on the flags
before they pass them to cifs_posix_open, whereas some don't. Two flag
conversion steps is just confusing though.

Change the function instead to clearly expect input in f_flags format,
and fix the callers to pass that in. Then, have cifs_posix_open call
cifs_convert_posix_flags to do the conversion. Move cifs_posix_open to
file.c as well so we can keep cifs_convert_posix_flags as a static
function.

Fix it also to not ignore O_CREAT, O_EXCL and O_TRUNC, and instead have
cifs_reopen_file mask those bits off before calling cifs_posix_open.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>
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Jeff Layton authored and Steve French committed Oct 18, 2010
1 parent 2f4f26f commit 608712f
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Showing 3 changed files with 95 additions and 119 deletions.
2 changes: 1 addition & 1 deletion fs/cifs/cifsproto.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -111,7 +111,7 @@ extern struct cifsFileInfo *cifs_new_fileinfo(struct inode *newinode,
unsigned int oflags, __u32 oplock);
extern int cifs_posix_open(char *full_path, struct inode **pinode,
struct super_block *sb,
int mode, int oflags,
int mode, unsigned int f_flags,
__u32 *poplock, __u16 *pnetfid, int xid);
void cifs_fill_uniqueid(struct super_block *sb, struct cifs_fattr *fattr);
extern void cifs_unix_basic_to_fattr(struct cifs_fattr *fattr,
Expand Down
99 changes: 6 additions & 93 deletions fs/cifs/dir.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -181,93 +181,6 @@ cifs_new_fileinfo(struct inode *newinode, __u16 fileHandle, struct file *file,
return pCifsFile;
}

int cifs_posix_open(char *full_path, struct inode **pinode,
struct super_block *sb, int mode, int oflags,
__u32 *poplock, __u16 *pnetfid, int xid)
{
int rc;
FILE_UNIX_BASIC_INFO *presp_data;
__u32 posix_flags = 0;
struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
struct cifs_fattr fattr;
struct tcon_link *tlink;
struct cifsTconInfo *tcon;

cFYI(1, "posix open %s", full_path);

presp_data = kzalloc(sizeof(FILE_UNIX_BASIC_INFO), GFP_KERNEL);
if (presp_data == NULL)
return -ENOMEM;

/* So far cifs posix extensions can only map the following flags.
There are other valid fmode oflags such as FMODE_LSEEK, FMODE_PREAD, but
so far we do not seem to need them, and we can treat them as local only */
if ((oflags & (FMODE_READ | FMODE_WRITE)) ==
(FMODE_READ | FMODE_WRITE))
posix_flags = SMB_O_RDWR;
else if (oflags & FMODE_READ)
posix_flags = SMB_O_RDONLY;
else if (oflags & FMODE_WRITE)
posix_flags = SMB_O_WRONLY;
if (oflags & O_CREAT)
posix_flags |= SMB_O_CREAT;
if (oflags & O_EXCL)
posix_flags |= SMB_O_EXCL;
if (oflags & O_TRUNC)
posix_flags |= SMB_O_TRUNC;
/* be safe and imply O_SYNC for O_DSYNC */
if (oflags & O_DSYNC)
posix_flags |= SMB_O_SYNC;
if (oflags & O_DIRECTORY)
posix_flags |= SMB_O_DIRECTORY;
if (oflags & O_NOFOLLOW)
posix_flags |= SMB_O_NOFOLLOW;
if (oflags & O_DIRECT)
posix_flags |= SMB_O_DIRECT;

mode &= ~current_umask();

tlink = cifs_sb_tlink(cifs_sb);
if (IS_ERR(tlink)) {
rc = PTR_ERR(tlink);
goto posix_open_ret;
}

tcon = tlink_tcon(tlink);
rc = CIFSPOSIXCreate(xid, tcon, posix_flags, mode, pnetfid, presp_data,
poplock, full_path, cifs_sb->local_nls,
cifs_sb->mnt_cifs_flags &
CIFS_MOUNT_MAP_SPECIAL_CHR);
cifs_put_tlink(tlink);

if (rc)
goto posix_open_ret;

if (presp_data->Type == cpu_to_le32(-1))
goto posix_open_ret; /* open ok, caller does qpathinfo */

if (!pinode)
goto posix_open_ret; /* caller does not need info */

cifs_unix_basic_to_fattr(&fattr, presp_data, cifs_sb);

/* get new inode and set it up */
if (*pinode == NULL) {
cifs_fill_uniqueid(sb, &fattr);
*pinode = cifs_iget(sb, &fattr);
if (!*pinode) {
rc = -ENOMEM;
goto posix_open_ret;
}
} else {
cifs_fattr_to_inode(*pinode, &fattr);
}

posix_open_ret:
kfree(presp_data);
return rc;
}

static void setup_cifs_dentry(struct cifsTconInfo *tcon,
struct dentry *direntry,
struct inode *newinode)
Expand Down Expand Up @@ -321,9 +234,9 @@ cifs_create(struct inode *inode, struct dentry *direntry, int mode,
oplock = REQ_OPLOCK;

if (nd && (nd->flags & LOOKUP_OPEN))
oflags = nd->intent.open.flags;
oflags = nd->intent.open.file->f_flags;
else
oflags = FMODE_READ | SMB_O_CREAT;
oflags = O_RDONLY | O_CREAT;

full_path = build_path_from_dentry(direntry);
if (full_path == NULL) {
Expand Down Expand Up @@ -359,9 +272,9 @@ cifs_create(struct inode *inode, struct dentry *direntry, int mode,
/* if the file is going to stay open, then we
need to set the desired access properly */
desiredAccess = 0;
if (oflags & FMODE_READ)
if (OPEN_FMODE(oflags) & FMODE_READ)
desiredAccess |= GENERIC_READ; /* is this too little? */
if (oflags & FMODE_WRITE)
if (OPEN_FMODE(oflags) & FMODE_WRITE)
desiredAccess |= GENERIC_WRITE;

if ((oflags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
Expand Down Expand Up @@ -716,11 +629,11 @@ cifs_lookup(struct inode *parent_dir_inode, struct dentry *direntry,
if (pTcon->unix_ext) {
if (nd && !(nd->flags & (LOOKUP_PARENT | LOOKUP_DIRECTORY)) &&
(nd->flags & LOOKUP_OPEN) && !pTcon->broken_posix_open &&
(nd->intent.open.flags & O_CREAT)) {
(nd->intent.open.file->f_flags & O_CREAT)) {
rc = cifs_posix_open(full_path, &newInode,
parent_dir_inode->i_sb,
nd->intent.open.create_mode,
nd->intent.open.flags, &oplock,
nd->intent.open.file->f_flags, &oplock,
&fileHandle, xid);
/*
* The check below works around a bug in POSIX
Expand Down
113 changes: 88 additions & 25 deletions fs/cifs/file.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -60,34 +60,32 @@ static inline int cifs_convert_flags(unsigned int flags)
FILE_READ_DATA);
}

static inline fmode_t cifs_posix_convert_flags(unsigned int flags)
static u32 cifs_posix_convert_flags(unsigned int flags)
{
fmode_t posix_flags = 0;
u32 posix_flags = 0;

if ((flags & O_ACCMODE) == O_RDONLY)
posix_flags = FMODE_READ;
posix_flags = SMB_O_RDONLY;
else if ((flags & O_ACCMODE) == O_WRONLY)
posix_flags = FMODE_WRITE;
else if ((flags & O_ACCMODE) == O_RDWR) {
/* GENERIC_ALL is too much permission to request
can cause unnecessary access denied on create */
/* return GENERIC_ALL; */
posix_flags = FMODE_READ | FMODE_WRITE;
}
/* can not map O_CREAT or O_EXCL or O_TRUNC flags when
reopening a file. They had their effect on the original open */
if (flags & O_APPEND)
posix_flags |= (fmode_t)O_APPEND;
posix_flags = SMB_O_WRONLY;
else if ((flags & O_ACCMODE) == O_RDWR)
posix_flags = SMB_O_RDWR;

if (flags & O_CREAT)
posix_flags |= SMB_O_CREAT;
if (flags & O_EXCL)
posix_flags |= SMB_O_EXCL;
if (flags & O_TRUNC)
posix_flags |= SMB_O_TRUNC;
/* be safe and imply O_SYNC for O_DSYNC */
if (flags & O_DSYNC)
posix_flags |= (fmode_t)O_DSYNC;
if (flags & __O_SYNC)
posix_flags |= (fmode_t)__O_SYNC;
posix_flags |= SMB_O_SYNC;
if (flags & O_DIRECTORY)
posix_flags |= (fmode_t)O_DIRECTORY;
posix_flags |= SMB_O_DIRECTORY;
if (flags & O_NOFOLLOW)
posix_flags |= (fmode_t)O_NOFOLLOW;
posix_flags |= SMB_O_NOFOLLOW;
if (flags & O_DIRECT)
posix_flags |= (fmode_t)O_DIRECT;
posix_flags |= SMB_O_DIRECT;

return posix_flags;
}
Expand Down Expand Up @@ -159,6 +157,68 @@ static inline int cifs_open_inode_helper(struct inode *inode,
return rc;
}

int cifs_posix_open(char *full_path, struct inode **pinode,
struct super_block *sb, int mode, unsigned int f_flags,
__u32 *poplock, __u16 *pnetfid, int xid)
{
int rc;
FILE_UNIX_BASIC_INFO *presp_data;
__u32 posix_flags = 0;
struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
struct cifs_fattr fattr;
struct tcon_link *tlink;
struct cifsTconInfo *tcon;

cFYI(1, "posix open %s", full_path);

presp_data = kzalloc(sizeof(FILE_UNIX_BASIC_INFO), GFP_KERNEL);
if (presp_data == NULL)
return -ENOMEM;

tlink = cifs_sb_tlink(cifs_sb);
if (IS_ERR(tlink)) {
rc = PTR_ERR(tlink);
goto posix_open_ret;
}

tcon = tlink_tcon(tlink);
mode &= ~current_umask();

posix_flags = cifs_posix_convert_flags(f_flags);
rc = CIFSPOSIXCreate(xid, tcon, posix_flags, mode, pnetfid, presp_data,
poplock, full_path, cifs_sb->local_nls,
cifs_sb->mnt_cifs_flags &
CIFS_MOUNT_MAP_SPECIAL_CHR);
cifs_put_tlink(tlink);

if (rc)
goto posix_open_ret;

if (presp_data->Type == cpu_to_le32(-1))
goto posix_open_ret; /* open ok, caller does qpathinfo */

if (!pinode)
goto posix_open_ret; /* caller does not need info */

cifs_unix_basic_to_fattr(&fattr, presp_data, cifs_sb);

/* get new inode and set it up */
if (*pinode == NULL) {
cifs_fill_uniqueid(sb, &fattr);
*pinode = cifs_iget(sb, &fattr);
if (!*pinode) {
rc = -ENOMEM;
goto posix_open_ret;
}
} else {
cifs_fattr_to_inode(*pinode, &fattr);
}

posix_open_ret:
kfree(presp_data);
return rc;
}

int cifs_open(struct inode *inode, struct file *file)
{
int rc = -EACCES;
Expand Down Expand Up @@ -205,12 +265,10 @@ int cifs_open(struct inode *inode, struct file *file)
(tcon->ses->capabilities & CAP_UNIX) &&
(CIFS_UNIX_POSIX_PATH_OPS_CAP &
le64_to_cpu(tcon->fsUnixInfo.Capability))) {
int oflags = (int) cifs_posix_convert_flags(file->f_flags);
oflags |= SMB_O_CREAT;
/* can not refresh inode info since size could be stale */
rc = cifs_posix_open(full_path, &inode, inode->i_sb,
cifs_sb->mnt_file_mode /* ignored */,
oflags, &oplock, &netfid, xid);
file->f_flags, &oplock, &netfid, xid);
if (rc == 0) {
cFYI(1, "posix open succeeded");

Expand Down Expand Up @@ -426,8 +484,13 @@ static int cifs_reopen_file(struct file *file, bool can_flush)
if (tcon->unix_ext && (tcon->ses->capabilities & CAP_UNIX) &&
(CIFS_UNIX_POSIX_PATH_OPS_CAP &
le64_to_cpu(tcon->fsUnixInfo.Capability))) {
int oflags = (int) cifs_posix_convert_flags(file->f_flags);
/* can not refresh inode info since size could be stale */

/*
* O_CREAT, O_EXCL and O_TRUNC already had their effect on the
* original open. Must mask them off for a reopen.
*/
unsigned int oflags = file->f_flags & ~(O_CREAT|O_EXCL|O_TRUNC);

rc = cifs_posix_open(full_path, NULL, inode->i_sb,
cifs_sb->mnt_file_mode /* ignored */,
oflags, &oplock, &netfid, xid);
Expand Down

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