CIFS: Fix wsize usage in iovec write

If a server change maximum buffer size for write (wsize) requests
on reconnect we can fail on repeating with a big size buffer on
-EAGAIN error in iovec write. Fix this by checking wsize all the
time before repeating request in iovec write.

Reviewed-by: Shirish Pargaonkar <spargaonkar@suse.com>
Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Steve French <smfrench@gmail.com>
This commit is contained in:
Pavel Shilovsky 2014-06-20 16:30:46 +04:00 committed by Steve French
parent 43de94eadf
commit 6ec0b01b26
3 changed files with 39 additions and 32 deletions

View File

@ -196,10 +196,6 @@ cifs_reconnect_tcon(struct cifs_tcon *tcon, int smb_command)
if (rc)
goto out;
/*
* FIXME: check if wsize needs updated due to negotiated smb buffer
* size shrinking
*/
atomic_inc(&tconInfoReconnectCount);
/* tell server Unix caps we support */

View File

@ -2401,28 +2401,6 @@ cifs_uncached_writev_complete(struct work_struct *work)
kref_put(&wdata->refcount, cifs_uncached_writedata_release);
}
/* attempt to send write to server, retry on any -EAGAIN errors */
static int
cifs_uncached_retry_writev(struct cifs_writedata *wdata)
{
int rc;
struct TCP_Server_Info *server;
server = tlink_tcon(wdata->cfile->tlink)->ses->server;
do {
if (wdata->cfile->invalidHandle) {
rc = cifs_reopen_file(wdata->cfile, false);
if (rc != 0)
continue;
}
rc = server->ops->async_writev(wdata,
cifs_uncached_writedata_release);
} while (rc == -EAGAIN);
return rc;
}
static int
wdata_fill_from_iovec(struct cifs_writedata *wdata, struct iov_iter *from,
size_t *len, unsigned long *num_pages)
@ -2474,13 +2452,19 @@ cifs_write_from_iter(loff_t offset, size_t len, struct iov_iter *from,
size_t cur_len;
unsigned long nr_pages, num_pages, i;
struct cifs_writedata *wdata;
struct iov_iter saved_from;
loff_t saved_offset = offset;
pid_t pid;
struct TCP_Server_Info *server;
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
pid = open_file->pid;
else
pid = current->tgid;
server = tlink_tcon(open_file->tlink)->ses->server;
memcpy(&saved_from, from, sizeof(struct iov_iter));
do {
nr_pages = get_numpages(cifs_sb->wsize, len, &cur_len);
wdata = cifs_writedata_alloc(nr_pages,
@ -2520,10 +2504,20 @@ cifs_write_from_iter(loff_t offset, size_t len, struct iov_iter *from,
wdata->bytes = cur_len;
wdata->pagesz = PAGE_SIZE;
wdata->tailsz = cur_len - ((nr_pages - 1) * PAGE_SIZE);
rc = cifs_uncached_retry_writev(wdata);
if (!wdata->cfile->invalidHandle ||
!cifs_reopen_file(wdata->cfile, false))
rc = server->ops->async_writev(wdata,
cifs_uncached_writedata_release);
if (rc) {
kref_put(&wdata->refcount,
cifs_uncached_writedata_release);
if (rc == -EAGAIN) {
memcpy(from, &saved_from,
sizeof(struct iov_iter));
iov_iter_advance(from, offset - saved_offset);
continue;
}
break;
}
@ -2545,6 +2539,7 @@ cifs_iovec_write(struct file *file, struct iov_iter *from, loff_t *poffset)
struct cifs_sb_info *cifs_sb;
struct cifs_writedata *wdata, *tmp;
struct list_head wdata_list;
struct iov_iter saved_from;
int rc;
len = iov_iter_count(from);
@ -2565,6 +2560,8 @@ cifs_iovec_write(struct file *file, struct iov_iter *from, loff_t *poffset)
if (!tcon->ses->server->ops->async_writev)
return -ENOSYS;
memcpy(&saved_from, from, sizeof(struct iov_iter));
rc = cifs_write_from_iter(*poffset, len, from, open_file, cifs_sb,
&wdata_list);
@ -2596,7 +2593,25 @@ restart_loop:
/* resend call if it's a retryable error */
if (rc == -EAGAIN) {
rc = cifs_uncached_retry_writev(wdata);
struct list_head tmp_list;
struct iov_iter tmp_from;
INIT_LIST_HEAD(&tmp_list);
list_del_init(&wdata->list);
memcpy(&tmp_from, &saved_from,
sizeof(struct iov_iter));
iov_iter_advance(&tmp_from,
wdata->offset - *poffset);
rc = cifs_write_from_iter(wdata->offset,
wdata->bytes, &tmp_from,
open_file, cifs_sb, &tmp_list);
list_splice(&tmp_list, &wdata_list);
kref_put(&wdata->refcount,
cifs_uncached_writedata_release);
goto restart_loop;
}
}

View File

@ -245,10 +245,6 @@ smb2_reconnect(__le16 smb2_command, struct cifs_tcon *tcon)
if (rc)
goto out;
atomic_inc(&tconInfoReconnectCount);
/*
* BB FIXME add code to check if wsize needs update due to negotiated
* smb buffer size shrinking.
*/
out:
/*
* Check if handle based operation so we know whether we can continue