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r17140: Get rid of the lock release/reacquire code ! Turns out

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that create dispositions that cause O_TRUNC break
oplocks. This simplifies the code - although we have
to keep separate the client requested access mask and
the access mask we actually use to open the file.
Jeremy.
This commit is contained in:
Jeremy Allison 2006-07-19 18:34:19 +00:00 committed by Gerald (Jerry) Carter
parent 906720649b
commit 3bcd52a475
1 changed files with 78 additions and 90 deletions
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168
source/smbd/open.c
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@ -1117,6 +1117,7 @@ NTSTATUS open_file_ntcreate(connection_struct *conn,
uint16 mid = get_current_mid();
struct timeval request_time = timeval_zero();
struct share_mode_lock *lck = NULL;
uint32 open_access_mask = access_mask;
NTSTATUS status;
if (conn->printer) {
@ -1208,12 +1209,14 @@ NTSTATUS open_file_ntcreate(connection_struct *conn,
/* If file exists replace/overwrite. If file doesn't
* exist create. */
flags2 |= (O_CREAT | O_TRUNC);
open_access_mask |= FILE_WRITE_DATA; /* This will cause oplock breaks. */
break;
case FILE_OVERWRITE_IF:
/* If file exists replace/overwrite. If file doesn't
* exist create. */
flags2 |= (O_CREAT | O_TRUNC);
open_access_mask |= FILE_WRITE_DATA; /* This will cause oplock breaks. */
break;
case FILE_OPEN:
@ -1238,6 +1241,7 @@ NTSTATUS open_file_ntcreate(connection_struct *conn,
return NT_STATUS_OBJECT_NAME_NOT_FOUND;
}
flags2 |= O_TRUNC;
open_access_mask |= FILE_WRITE_DATA; /* This will cause oplock breaks. */
break;
case FILE_CREATE:
@ -1289,7 +1293,10 @@ NTSTATUS open_file_ntcreate(connection_struct *conn,
/* This is a nasty hack - must fix... JRA. */
if (access_mask == MAXIMUM_ALLOWED_ACCESS) {
access_mask = FILE_GENERIC_ALL;
open_access_mask = access_mask = FILE_GENERIC_ALL;
if (flags2 & O_TRUNC) {
open_access_mask |= FILE_WRITE_DATA; /* This will cause oplock breaks. */
}
}
/*
@ -1353,7 +1360,7 @@ NTSTATUS open_file_ntcreate(connection_struct *conn,
fsp->inode = psbuf->st_ino;
fsp->share_access = share_access;
fsp->fh->private_options = create_options;
fsp->access_mask = access_mask;
fsp->access_mask = open_access_mask; /* We change this to the requested access_mask after the open is done. */
/* Ensure no SAMBA_PRIVATE bits can be set. */
fsp->oplock_type = (oplock_request & ~SAMBA_PRIVATE_OPLOCK_MASK);
@ -1383,6 +1390,7 @@ NTSTATUS open_file_ntcreate(connection_struct *conn,
return NT_STATUS_SHARING_VIOLATION;
}
/* Use the client requested access mask here, not the one we open with. */
status = open_mode_check(conn, fname, lck,
access_mask, share_access,
create_options, &file_existed);
@ -1417,6 +1425,8 @@ NTSTATUS open_file_ntcreate(connection_struct *conn,
(NTCREATEX_OPTIONS_PRIVATE_DENY_DOS|
NTCREATEX_OPTIONS_PRIVATE_DENY_FCB)) {
files_struct *fsp_dup;
/* Use the client requested access mask here, not the one we open with. */
fsp_dup = fcb_or_dos_open(conn, fname, dev,
inode, access_mask,
share_access,
@ -1533,114 +1543,92 @@ NTSTATUS open_file_ntcreate(connection_struct *conn,
(unsigned int)flags, (unsigned int)flags2,
(unsigned int)unx_mode));
/* Drop the lock before doing any real file access. Allows kernel
oplock breaks to be processed. Handle any races after the open
call when we re-acquire the lock. */
if (lck) {
TALLOC_FREE(lck);
}
/*
* open_file strips any O_TRUNC flags itself.
*/
fsp_open = open_file(fsp,conn,fname,psbuf,flags|flags2,unx_mode,
access_mask);
fsp_open = open_file(fsp,conn,fname,psbuf,flags|flags2,unx_mode, open_access_mask);
if (!NT_STATUS_IS_OK(fsp_open)) {
if (lck != NULL) {
TALLOC_FREE(lck);
}
file_free(fsp);
return fsp_open;
}
/*
* Deal with the race condition where two smbd's detect the
* file doesn't exist and do the create at the same time. One
* of them will win and set a share mode, the other (ie. this
* one) should check if the requested share mode for this
* create is allowed.
*/
if (!file_existed) {
/*
* Now the file exists and fsp is successfully opened,
* fsp->dev and fsp->inode are valid and should replace the
* dev=0,inode=0 from a non existent file. Spotted by
* Nadav Danieli <nadavd@exanet.com>. JRA.
*/
/*
* Deal with the race condition where two smbd's detect the
* file doesn't exist and do the create at the same time. One
* of them will win and set a share mode, the other (ie. this
* one) should check if the requested share mode for this
* create is allowed.
*/
dev = fsp->dev;
inode = fsp->inode;
/*
* Now the file exists and fsp is successfully opened,
* fsp->dev and fsp->inode are valid and should replace the
* dev=0,inode=0 from a non existent file. Spotted by
* Nadav Danieli <nadavd@exanet.com>. JRA.
*/
lck = get_share_mode_lock(NULL, dev, inode,
conn->connectpath,
fname);
dev = fsp->dev;
inode = fsp->inode;
if (lck == NULL) {
DEBUG(0, ("open_file_ntcreate: Could not get share mode lock for %s\n", fname));
fd_close(conn, fsp);
file_free(fsp);
return NT_STATUS_SHARING_VIOLATION;
}
lck = get_share_mode_lock(NULL, dev, inode,
conn->connectpath,
fname);
/*
* The share entry is again *locked*.....
*/
/* First pass - send break only on batch oplocks. */
if (delay_for_oplocks(lck, fsp, 1, oplock_request)) {
schedule_defer_open(lck, request_time);
fd_close(conn, fsp);
file_free(fsp);
TALLOC_FREE(lck);
return NT_STATUS_SHARING_VIOLATION;
}
status = open_mode_check(conn, fname, lck,
access_mask, share_access,
create_options, &file_existed);
if (NT_STATUS_IS_OK(status)) {
/* We might be going to allow this open. Check oplock status again. */
/* Second pass - send break for both batch or exclusive oplocks. */
if (delay_for_oplocks(lck, fsp, 2, oplock_request)) {
schedule_defer_open(lck, request_time);
if (lck == NULL) {
DEBUG(0, ("open_file_ntcreate: Could not get share mode lock for %s\n", fname));
fd_close(conn, fsp);
file_free(fsp);
TALLOC_FREE(lck);
return NT_STATUS_SHARING_VIOLATION;
}
status = open_mode_check(conn, fname, lck,
access_mask, share_access,
create_options, &file_existed);
if (NT_STATUS_EQUAL(status, NT_STATUS_DELETE_PENDING)) {
/* DELETE_PENDING is not deferred for a second */
TALLOC_FREE(lck);
file_free(fsp);
return status;
}
if (!NT_STATUS_IS_OK(status)) {
struct deferred_open_record state;
fd_close(conn, fsp);
file_free(fsp);
state.delayed_for_oplocks = False;
state.dev = dev;
state.inode = inode;
/* Do it all over again immediately. In the second
* round we will find that the file existed and handle
* the DELETE_PENDING and FCB cases correctly. No need
* to duplicate the code here. Essentially this is a
* "goto top of this function", but don't tell
* anybody... */
defer_open(lck, request_time, timeval_zero(),
&state);
TALLOC_FREE(lck);
return status;
}
/*
* We exit this block with the share entry *locked*.....
*/
}
if (NT_STATUS_EQUAL(status, NT_STATUS_DELETE_PENDING)) {
/* DELETE_PENDING is not deferred for a second */
fd_close(conn, fsp);
file_free(fsp);
TALLOC_FREE(lck);
return status;
}
if (!NT_STATUS_IS_OK(status)) {
struct deferred_open_record state;
fd_close(conn, fsp);
file_free(fsp);
state.delayed_for_oplocks = False;
state.dev = dev;
state.inode = inode;
/* Do it all over again immediately. In the second
* round we will find that the file existed and handle
* the DELETE_PENDING and FCB cases correctly. No need
* to duplicate the code here. Essentially this is a
* "goto top of this function", but don't tell
* anybody... */
defer_open(lck, request_time, timeval_zero(),
&state);
TALLOC_FREE(lck);
return status;
}
SMB_ASSERT(lck != NULL);
/* note that we ignore failure for the following. It is
basically a hack for NFS, and NFS will never set one of
@ -1683,7 +1671,7 @@ NTSTATUS open_file_ntcreate(connection_struct *conn,
if (file_existed) {
/* stat opens on existing files don't get oplocks. */
if (is_stat_open(fsp->access_mask)) {
if (is_stat_open(open_access_mask)) {
fsp->oplock_type = NO_OPLOCK;
}