From: Long Li <longli@linuxonhyperv.com>
To: Steve French <sfrench@samba.org>,
linux-cifs@vger.kernel.org, samba-technical@lists.samba.org,
linux-kernel@vger.kernel.org, linux-rdma@vger.kernel.org,
Dan Carpenter <dan.carpenter@oracle.com>
Cc: Long Li <longli@microsoft.com>
Subject: [PATCH] CIFS: Avoid returning EBUSY to upper layer VFS
Date: Thu, 6 Dec 2018 04:51:06 +0000 [thread overview]
Message-ID: <20181206045106.10307-1-longli@linuxonhyperv.com> (raw)
From: Long Li <longli@microsoft.com>
EBUSY is not handled by VFS, and will be passed to user-mode. This is not
correct as we need to wait for more credits.
This patch also fixes a bug where rsize or wsize is used uninitialized when
the call to server->ops->wait_mtu_credits() fails.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Long Li <longli@microsoft.com>
---
fs/cifs/file.c | 31 ++++++-------------------------
1 file changed, 6 insertions(+), 25 deletions(-)
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index 74c33d5..c9bc56b 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -2541,14 +2541,13 @@ static int
cifs_resend_wdata(struct cifs_writedata *wdata, struct list_head *wdata_list,
struct cifs_aio_ctx *ctx)
{
- int wait_retry = 0;
unsigned int wsize, credits;
int rc;
struct TCP_Server_Info *server =
tlink_tcon(wdata->cfile->tlink)->ses->server;
/*
- * Try to resend this wdata, waiting for credits up to 3 seconds.
+ * Wait for credits to resend this wdata.
* Note: we are attempting to resend the whole wdata not in segments
*/
do {
@@ -2556,19 +2555,13 @@ cifs_resend_wdata(struct cifs_writedata *wdata, struct list_head *wdata_list,
server, wdata->bytes, &wsize, &credits);
if (rc)
- break;
+ goto out;
if (wsize < wdata->bytes) {
add_credits_and_wake_if(server, credits, 0);
msleep(1000);
- wait_retry++;
}
- } while (wsize < wdata->bytes && wait_retry < 3);
-
- if (wsize < wdata->bytes) {
- rc = -EBUSY;
- goto out;
- }
+ } while (wsize < wdata->bytes);
rc = -EAGAIN;
while (rc == -EAGAIN) {
@@ -3234,14 +3227,13 @@ static int cifs_resend_rdata(struct cifs_readdata *rdata,
struct list_head *rdata_list,
struct cifs_aio_ctx *ctx)
{
- int wait_retry = 0;
unsigned int rsize, credits;
int rc;
struct TCP_Server_Info *server =
tlink_tcon(rdata->cfile->tlink)->ses->server;
/*
- * Try to resend this rdata, waiting for credits up to 3 seconds.
+ * Wait for credits to resend this rdata.
* Note: we are attempting to resend the whole rdata not in segments
*/
do {
@@ -3249,24 +3241,13 @@ static int cifs_resend_rdata(struct cifs_readdata *rdata,
&rsize, &credits);
if (rc)
- break;
+ goto out;
if (rsize < rdata->bytes) {
add_credits_and_wake_if(server, credits, 0);
msleep(1000);
- wait_retry++;
}
- } while (rsize < rdata->bytes && wait_retry < 3);
-
- /*
- * If we can't find enough credits to send this rdata
- * release the rdata and return failure, this will pass
- * whatever I/O amount we have finished to VFS.
- */
- if (rsize < rdata->bytes) {
- rc = -EBUSY;
- goto out;
- }
+ } while (rsize < rdata->bytes);
rc = -EAGAIN;
while (rc == -EAGAIN) {
--
2.7.4
next reply other threads:[~2018-12-06 4:52 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-12-06 4:51 Long Li [this message]
2018-12-06 8:29 ` [PATCH] CIFS: Avoid returning EBUSY to upper layer VFS Steve French
2018-12-07 1:47 ` Pavel Shilovsky
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