| Message ID | 20181206045106.10307-1-longli@linuxonhyperv.com |
|---|---|
| State | New |
| Headers | show |
| Series | CIFS: Avoid returning EBUSY to upper layer VFS | expand |
Tentatively pushed to cifs-2.6.git for-next On Wed, Dec 5, 2018 at 10:52 PM Long Li <longli@linuxonhyperv.com> wrote: > > 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 >
чт, 6 дек. 2018 г. в 00:29, Steve French via samba-technical <samba-technical@lists.samba.org>: > > Tentatively pushed to cifs-2.6.git for-next > On Wed, Dec 5, 2018 at 10:52 PM Long Li <longli@linuxonhyperv.com> wrote: > > > > 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 > > > > > -- > Thanks, > > Steve > Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com> -- Best regards, Pavel Shilovsky
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) {