xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

CIFS: Add rwpidforward mount option

Browse Source 
Add rwpidforward mount option that switches on a mode when we forward
pid of a process who opened a file to any read and write operation.

This can prevent applications like WINE from failing on read or write
operation on a previously locked file region from the same netfd from
another process if we use mandatory brlock style.

It is actual for WINE because during a run of WINE program two processes
work on the same netfd - share the same file struct between several VFS
fds:
1) WINE-server does open and lock;
2) WINE-application does read and write.

Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <sfrench@us.ibm.com>
This commit is contained in:
Pavel Shilovsky
2011-05-26 06:02:00 +00:00
committed by Steve French
parent 25c7f41e92
commit d4ffff1fa9
10 changed files with 115 additions and 39 deletions
Download Patch File Download Diff File Expand all files Collapse all files

11
fs/cifs/inode.c
View File

@@ -374,6 +374,7 @@ cifs_sfu_type(struct cifs_fattr *fattr, const unsigned char *path,
__u16 netfid;
struct tcon_link *tlink;
struct cifsTconInfo *tcon;
struct cifs_io_parms io_parms;
char buf[24];
unsigned int bytes_read;
char *pbuf;
@@ -405,9 +406,13 @@ cifs_sfu_type(struct cifs_fattr *fattr, const unsigned char *path,
if (rc == 0) {
int buf_type = CIFS_NO_BUFFER;
/* Read header */
rc = CIFSSMBRead(xid, tcon, netfid,
24 /* length */, 0 /* offset */,
&bytes_read, &pbuf, &buf_type);
io_parms.netfid = netfid;
io_parms.pid = current->tgid;
io_parms.tcon = tcon;
io_parms.offset = 0;
io_parms.length = 24;
rc = CIFSSMBRead(xid, &io_parms, &bytes_read, &pbuf,
&buf_type);
if ((rc == 0) && (bytes_read >= 8)) {
if (memcmp("IntxBLK", pbuf, 8) == 0) {
cFYI(1, "Block device");