From: Bartlomiej Zolnierkiewicz <[email protected]>
Subject: [PATCH] mg_disk: fix issue with data integrity on error in mg_write()
We cannot acknowledge the sector write before checking its status
(which is done on the next loop iteration) and we also need to do
the final status register check after writing the last sector.
Fix mg_write() to match mg_write_intr() in this regard.
While at it:
- add mg_read_one() and mg_write_one() helpers
- always use MG_SECTOR_SIZE and remove MG_STORAGE_BUFFER_SIZE
[bart: thanks to Tejun for porting the patch over recent block changes]
Cc: unsik Kim <[email protected]>
Cc: Tejun Heo <[email protected]>
Signed-off-by: Bartlomiej Zolnierkiewicz <[email protected]>
---
Ported over 2.6.31-rc1.
drivers/block/mg_disk.c | 89 +++++++++++++++++++++++++-----------------------
1 file changed, 47 insertions(+), 42 deletions(-)
Index: b/drivers/block/mg_disk.c
===================================================================
--- a/drivers/block/mg_disk.c
+++ b/drivers/block/mg_disk.c
@@ -36,7 +36,6 @@
/* Register offsets */
#define MG_BUFF_OFFSET 0x8000
-#define MG_STORAGE_BUFFER_SIZE 0x200
#define MG_REG_OFFSET 0xC000
#define MG_REG_FEATURE (MG_REG_OFFSET + 2) /* write case */
#define MG_REG_ERROR (MG_REG_OFFSET + 2) /* read case */
@@ -469,9 +468,18 @@ static unsigned int mg_out(struct mg_hos
return MG_ERR_NONE;
}
+static void mg_read_one(struct mg_host *host, struct request *req)
+{
+ u16 *buff = (u16 *)req->buffer;
+ u32 i;
+
+ for (i = 0; i < MG_SECTOR_SIZE >> 1; i++)
+ *buff++ = inw((unsigned long)host->dev_base + MG_BUFF_OFFSET +
+ (i << 1));
+}
+
static void mg_read(struct request *req)
{
- u32 j;
struct mg_host *host = req->rq_disk->private_data;
if (mg_out(host, blk_rq_pos(req), blk_rq_sectors(req),
@@ -482,26 +490,33 @@ static void mg_read(struct request *req)
blk_rq_sectors(req), blk_rq_pos(req), req->buffer);
do {
- u16 *buff = (u16 *)req->buffer;
-
if (mg_wait(host, ATA_DRQ,
MG_TMAX_WAIT_RD_DRQ) != MG_ERR_NONE) {
mg_bad_rw_intr(host);
return;
}
- for (j = 0; j < MG_SECTOR_SIZE >> 1; j++)
- *buff++ = inw((unsigned long)host->dev_base +
- MG_BUFF_OFFSET + (j << 1));
+
+ mg_read_one(host, req);
outb(MG_CMD_RD_CONF, (unsigned long)host->dev_base +
MG_REG_COMMAND);
} while (mg_end_request(host, 0, MG_SECTOR_SIZE));
}
+static void mg_write_one(struct mg_host *host, struct request *req)
+{
+ u16 *buff = (u16 *)req->buffer;
+ u32 i;
+
+ for (i = 0; i < MG_SECTOR_SIZE >> 1; i++)
+ outw(*buff++, (unsigned long)host->dev_base + MG_BUFF_OFFSET +
+ (i << 1));
+}
+
static void mg_write(struct request *req)
{
- u32 j;
struct mg_host *host = req->rq_disk->private_data;
+ bool rem;
if (mg_out(host, blk_rq_pos(req), blk_rq_sectors(req),
MG_CMD_WR, NULL) != MG_ERR_NONE) {
@@ -512,27 +527,37 @@ static void mg_write(struct request *req
MG_DBG("requested %d sects (from %ld), buffer=0x%p\n",
blk_rq_sectors(req), blk_rq_pos(req), req->buffer);
- do {
- u16 *buff = (u16 *)req->buffer;
+ if (mg_wait(host, ATA_DRQ,
+ MG_TMAX_WAIT_WR_DRQ) != MG_ERR_NONE) {
+ mg_bad_rw_intr(host);
+ return;
+ }
+
+ mg_write_one(host, req);
+
+ outb(MG_CMD_WR_CONF, (unsigned long)host->dev_base + MG_REG_COMMAND);
- if (mg_wait(host, ATA_DRQ, MG_TMAX_WAIT_WR_DRQ) != MG_ERR_NONE) {
+ do {
+ if (blk_rq_sectors(req) > 1 &&
+ mg_wait(host, ATA_DRQ,
+ MG_TMAX_WAIT_WR_DRQ) != MG_ERR_NONE) {
mg_bad_rw_intr(host);
return;
}
- for (j = 0; j < MG_SECTOR_SIZE >> 1; j++)
- outw(*buff++, (unsigned long)host->dev_base +
- MG_BUFF_OFFSET + (j << 1));
- outb(MG_CMD_WR_CONF, (unsigned long)host->dev_base +
- MG_REG_COMMAND);
- } while (mg_end_request(host, 0, MG_SECTOR_SIZE));
+ rem = mg_end_request(host, 0, MG_SECTOR_SIZE);
+ if (rem)
+ mg_write_one(host, req);
+
+ outb(MG_CMD_WR_CONF,
+ (unsigned long)host->dev_base + MG_REG_COMMAND);
+ } while (rem);
}
static void mg_read_intr(struct mg_host *host)
{
struct request *req = host->req;
u32 i;
- u16 *buff;
/* check status */
do {
@@ -550,13 +575,7 @@ static void mg_read_intr(struct mg_host
return;
ok_to_read:
- /* get current segment of request */
- buff = (u16 *)req->buffer;
-
- /* read 1 sector */
- for (i = 0; i < MG_SECTOR_SIZE >> 1; i++)
- *buff++ = inw((unsigned long)host->dev_base + MG_BUFF_OFFSET +
- (i << 1));
+ mg_read_one(host, req);
MG_DBG("sector %ld, remaining=%ld, buffer=0x%p\n",
blk_rq_pos(req), blk_rq_sectors(req) - 1, req->buffer);
@@ -575,8 +594,7 @@ ok_to_read:
static void mg_write_intr(struct mg_host *host)
{
struct request *req = host->req;
- u32 i, j;
- u16 *buff;
+ u32 i;
bool rem;
/* check status */
@@ -597,12 +615,7 @@ static void mg_write_intr(struct mg_host
ok_to_write:
if ((rem = mg_end_request(host, 0, MG_SECTOR_SIZE))) {
/* write 1 sector and set handler if remains */
- buff = (u16 *)req->buffer;
- for (j = 0; j < MG_STORAGE_BUFFER_SIZE >> 1; j++) {
- outw(*buff, (unsigned long)host->dev_base +
- MG_BUFF_OFFSET + (j << 1));
- buff++;
- }
+ mg_write_one(host, req);
MG_DBG("sector %ld, remaining=%ld, buffer=0x%p\n",
blk_rq_pos(req), blk_rq_sectors(req), req->buffer);
host->mg_do_intr = mg_write_intr;
@@ -667,9 +680,6 @@ static unsigned int mg_issue_req(struct
unsigned int sect_num,
unsigned int sect_cnt)
{
- u16 *buff;
- u32 i;
-
switch (rq_data_dir(req)) {
case READ:
if (mg_out(host, sect_num, sect_cnt, MG_CMD_RD, &mg_read_intr)
@@ -693,12 +703,7 @@ static unsigned int mg_issue_req(struct
mg_bad_rw_intr(host);
return host->error;
}
- buff = (u16 *)req->buffer;
- for (i = 0; i < MG_SECTOR_SIZE >> 1; i++) {
- outw(*buff, (unsigned long)host->dev_base +
- MG_BUFF_OFFSET + (i << 1));
- buff++;
- }
+ mg_write_one(host, req);
mod_timer(&host->timer, jiffies + 3 * HZ);
outb(MG_CMD_WR_CONF, (unsigned long)host->dev_base +
MG_REG_COMMAND);
2009/6/29 Bartlomiej Zolnierkiewicz <[email protected]>:
> From: Bartlomiej Zolnierkiewicz <[email protected]>
> Subject: [PATCH] mg_disk: fix issue with data integrity on error in mg_write()
>
> We cannot acknowledge the sector write before checking its status
> (which is done on the next loop iteration) and we also need to do
> the final status register check after writing the last sector.
Right. Current mg_disk polling driver doesn't check status register
(should be ready status) after writing last sector. Thanks.
> static void mg_write(struct request *req)
> {
> - u32 j;
> struct mg_host *host = req->rq_disk->private_data;
> + bool rem;
>
> if (mg_out(host, blk_rq_pos(req), blk_rq_sectors(req),
> MG_CMD_WR, NULL) != MG_ERR_NONE) {
> @@ -512,27 +527,37 @@ static void mg_write(struct request *req
> MG_DBG("requested %d sects (from %ld), buffer=0x%p\n",
> blk_rq_sectors(req), blk_rq_pos(req), req->buffer);
>
> - do {
> - u16 *buff = (u16 *)req->buffer;
> + if (mg_wait(host, ATA_DRQ,
> + MG_TMAX_WAIT_WR_DRQ) != MG_ERR_NONE) {
> + mg_bad_rw_intr(host);
> + return;
> + }
> +
> + mg_write_one(host, req);
> +
> + outb(MG_CMD_WR_CONF, (unsigned long)host->dev_base + MG_REG_COMMAND);
>
> - if (mg_wait(host, ATA_DRQ, MG_TMAX_WAIT_WR_DRQ) != MG_ERR_NONE) {
> + do {
> + if (blk_rq_sectors(req) > 1 &&
> + mg_wait(host, ATA_DRQ,
> + MG_TMAX_WAIT_WR_DRQ) != MG_ERR_NONE) {
> mg_bad_rw_intr(host);
> return;
> }
> - for (j = 0; j < MG_SECTOR_SIZE >> 1; j++)
> - outw(*buff++, (unsigned long)host->dev_base +
> - MG_BUFF_OFFSET + (j << 1));
>
> - outb(MG_CMD_WR_CONF, (unsigned long)host->dev_base +
> - MG_REG_COMMAND);
> - } while (mg_end_request(host, 0, MG_SECTOR_SIZE));
> + rem = mg_end_request(host, 0, MG_SECTOR_SIZE);
> + if (rem)
> + mg_write_one(host, req);
> +
> + outb(MG_CMD_WR_CONF,
> + (unsigned long)host->dev_base + MG_REG_COMMAND);
> + } while (rem);
> }
I think checking ready status after do-while loop is enough.
static void mg_write(struct request *req)
{
u32 j;
struct mg_host *host = req->rq_disk->private_data;
if (mg_out(host, blk_rq_pos(req), blk_rq_sectors(req),
MG_CMD_WR, NULL) != MG_ERR_NONE) {
mg_bad_rw_intr(host);
return;
}
MG_DBG("requested %d sects (from %ld), buffer=0x%p\n",
blk_rq_sectors(req), blk_rq_pos(req), req->buffer);
do {
u16 *buff = (u16 *)req->buffer;
if (mg_wait(host, ATA_DRQ, MG_TMAX_WAIT_WR_DRQ) !=
MG_ERR_NONE) {
mg_bad_rw_intr(host);
return;
}
for (j = 0; j < MG_SECTOR_SIZE >> 1; j++)
outw(*buff++, (unsigned long)host->dev_base +
MG_BUFF_OFFSET + (j << 1));
outb(MG_CMD_WR_CONF, (unsigned long)host->dev_base +
MG_REG_COMMAND);
} while (mg_end_request(host, 0, MG_SECTOR_SIZE));
+ if (mg_wait(host, MG_STAT_READY, MG_TMAX_WAIT_WR_DRQ) !=
+ MG_ERR_NONE)
+ mg_bad_rw_intr(host);
}
---
Regards,
unsik Kim <[email protected]>
On Friday 03 July 2009 03:50:19 unsik Kim wrote:
> 2009/6/29 Bartlomiej Zolnierkiewicz <[email protected]>:
> > From: Bartlomiej Zolnierkiewicz <[email protected]>
> > Subject: [PATCH] mg_disk: fix issue with data integrity on error in mg_write()
> >
> > We cannot acknowledge the sector write before checking its status
> > (which is done on the next loop iteration) and we also need to do
> > the final status register check after writing the last sector.
>
> Right. Current mg_disk polling driver doesn't check status register
> (should be ready status) after writing last sector. Thanks.
>
>
> > static void mg_write(struct request *req)
> > {
> > - u32 j;
> > struct mg_host *host = req->rq_disk->private_data;
> > + bool rem;
> >
> > if (mg_out(host, blk_rq_pos(req), blk_rq_sectors(req),
> > MG_CMD_WR, NULL) != MG_ERR_NONE) {
> > @@ -512,27 +527,37 @@ static void mg_write(struct request *req
> > MG_DBG("requested %d sects (from %ld), buffer=0x%p\n",
> > blk_rq_sectors(req), blk_rq_pos(req), req->buffer);
> >
> > - do {
> > - u16 *buff = (u16 *)req->buffer;
> > + if (mg_wait(host, ATA_DRQ,
> > + MG_TMAX_WAIT_WR_DRQ) != MG_ERR_NONE) {
> > + mg_bad_rw_intr(host);
> > + return;
> > + }
> > +
> > + mg_write_one(host, req);
> > +
> > + outb(MG_CMD_WR_CONF, (unsigned long)host->dev_base + MG_REG_COMMAND);
> >
> > - if (mg_wait(host, ATA_DRQ, MG_TMAX_WAIT_WR_DRQ) != MG_ERR_NONE) {
> > + do {
> > + if (blk_rq_sectors(req) > 1 &&
> > + mg_wait(host, ATA_DRQ,
> > + MG_TMAX_WAIT_WR_DRQ) != MG_ERR_NONE) {
> > mg_bad_rw_intr(host);
> > return;
> > }
> > - for (j = 0; j < MG_SECTOR_SIZE >> 1; j++)
> > - outw(*buff++, (unsigned long)host->dev_base +
> > - MG_BUFF_OFFSET + (j << 1));
> >
> > - outb(MG_CMD_WR_CONF, (unsigned long)host->dev_base +
> > - MG_REG_COMMAND);
> > - } while (mg_end_request(host, 0, MG_SECTOR_SIZE));
> > + rem = mg_end_request(host, 0, MG_SECTOR_SIZE);
> > + if (rem)
> > + mg_write_one(host, req);
> > +
> > + outb(MG_CMD_WR_CONF,
> > + (unsigned long)host->dev_base + MG_REG_COMMAND);
> > + } while (rem);
> > }
>
> I think checking ready status after do-while loop is enough.
>
> static void mg_write(struct request *req)
> {
> u32 j;
> struct mg_host *host = req->rq_disk->private_data;
>
> if (mg_out(host, blk_rq_pos(req), blk_rq_sectors(req),
> MG_CMD_WR, NULL) != MG_ERR_NONE) {
> mg_bad_rw_intr(host);
> return;
> }
>
> MG_DBG("requested %d sects (from %ld), buffer=0x%p\n",
> blk_rq_sectors(req), blk_rq_pos(req), req->buffer);
>
> do {
> u16 *buff = (u16 *)req->buffer;
>
> if (mg_wait(host, ATA_DRQ, MG_TMAX_WAIT_WR_DRQ) !=
> MG_ERR_NONE) {
> mg_bad_rw_intr(host);
> return;
> }
> for (j = 0; j < MG_SECTOR_SIZE >> 1; j++)
> outw(*buff++, (unsigned long)host->dev_base +
> MG_BUFF_OFFSET + (j << 1));
>
> outb(MG_CMD_WR_CONF, (unsigned long)host->dev_base +
> MG_REG_COMMAND);
> } while (mg_end_request(host, 0, MG_SECTOR_SIZE));
>
> + if (mg_wait(host, MG_STAT_READY, MG_TMAX_WAIT_WR_DRQ) !=
> + MG_ERR_NONE)
> + mg_bad_rw_intr(host);
> }
I'm not sure about this -- I chose more invasive way cause it seems that
mg_end_request() may already complete the request (marking it as successful
and making block layer pass the data to upper layers) _before_ we really
check the status _after_ transferring the last sector of the command..
When last sector is written, ready bit of status register should be
checked.
Signed-off-by: unsik Kim <[email protected]>
---
drivers/block/mg_disk.c | 32 +++++++++++++++-----------------
1 files changed, 15 insertions(+), 17 deletions(-)
diff --git a/drivers/block/mg_disk.c b/drivers/block/mg_disk.c
index f8149db..64f90f5 100644
--- a/drivers/block/mg_disk.c
+++ b/drivers/block/mg_disk.c
@@ -516,16 +516,16 @@ static void mg_write_one(struct mg_host *host, struct request *req)
static void mg_write(struct request *req)
{
struct mg_host *host = req->rq_disk->private_data;
- bool rem;
+ unsigned int rem = blk_rq_sectors(req);
- if (mg_out(host, blk_rq_pos(req), blk_rq_sectors(req),
+ if (mg_out(host, blk_rq_pos(req), rem,
MG_CMD_WR, NULL) != MG_ERR_NONE) {
mg_bad_rw_intr(host);
return;
}
MG_DBG("requested %d sects (from %ld), buffer=0x%p\n",
- blk_rq_sectors(req), blk_rq_pos(req), req->buffer);
+ rem, blk_rq_pos(req), req->buffer);
if (mg_wait(host, ATA_DRQ,
MG_TMAX_WAIT_WR_DRQ) != MG_ERR_NONE) {
@@ -533,25 +533,23 @@ static void mg_write(struct request *req)
return;
}
- mg_write_one(host, req);
+ do {
+ mg_write_one(host, req);
- outb(MG_CMD_WR_CONF, (unsigned long)host->dev_base + MG_REG_COMMAND);
+ outb(MG_CMD_WR_CONF, (unsigned long)host->dev_base +
+ MG_REG_COMMAND);
- do {
- if (blk_rq_sectors(req) > 1 &&
- mg_wait(host, ATA_DRQ,
- MG_TMAX_WAIT_WR_DRQ) != MG_ERR_NONE) {
+ rem--;
+ if (rem > 1 && mg_wait(host, ATA_DRQ,
+ MG_TMAX_WAIT_WR_DRQ) != MG_ERR_NONE) {
+ mg_bad_rw_intr(host);
+ return;
+ } else if (mg_wait(host, MG_STAT_READY,
+ MG_TMAX_WAIT_WR_DRQ) != MG_ERR_NONE) {
mg_bad_rw_intr(host);
return;
}
-
- rem = mg_end_request(host, 0, MG_SECTOR_SIZE);
- if (rem)
- mg_write_one(host, req);
-
- outb(MG_CMD_WR_CONF,
- (unsigned long)host->dev_base + MG_REG_COMMAND);
- } while (rem);
+ } while (mg_end_request(host, 0, MG_SECTOR_SIZE));
}
static void mg_read_intr(struct mg_host *host)
--
1.6.0.6
On Thursday 23 July 2009 06:21:18 unsik Kim wrote:
> When last sector is written, ready bit of status register should be
> checked.
>
> Signed-off-by: unsik Kim <[email protected]>
Acked-by: Bartlomiej Zolnierkiewicz <[email protected]>
[ It is on top of my patch (http://lkml.org/lkml/2009/6/28/237), right?
I assume that both patches were verified with hardware and are ready
to be merged upstream now? ]
> ---
> drivers/block/mg_disk.c | 32 +++++++++++++++-----------------
> 1 files changed, 15 insertions(+), 17 deletions(-)
>
> diff --git a/drivers/block/mg_disk.c b/drivers/block/mg_disk.c
> index f8149db..64f90f5 100644
> --- a/drivers/block/mg_disk.c
> +++ b/drivers/block/mg_disk.c
> @@ -516,16 +516,16 @@ static void mg_write_one(struct mg_host *host, struct request *req)
> static void mg_write(struct request *req)
> {
> struct mg_host *host = req->rq_disk->private_data;
> - bool rem;
> + unsigned int rem = blk_rq_sectors(req);
>
> - if (mg_out(host, blk_rq_pos(req), blk_rq_sectors(req),
> + if (mg_out(host, blk_rq_pos(req), rem,
> MG_CMD_WR, NULL) != MG_ERR_NONE) {
> mg_bad_rw_intr(host);
> return;
> }
>
> MG_DBG("requested %d sects (from %ld), buffer=0x%p\n",
> - blk_rq_sectors(req), blk_rq_pos(req), req->buffer);
> + rem, blk_rq_pos(req), req->buffer);
>
> if (mg_wait(host, ATA_DRQ,
> MG_TMAX_WAIT_WR_DRQ) != MG_ERR_NONE) {
> @@ -533,25 +533,23 @@ static void mg_write(struct request *req)
> return;
> }
>
> - mg_write_one(host, req);
> + do {
> + mg_write_one(host, req);
>
> - outb(MG_CMD_WR_CONF, (unsigned long)host->dev_base + MG_REG_COMMAND);
> + outb(MG_CMD_WR_CONF, (unsigned long)host->dev_base +
> + MG_REG_COMMAND);
>
> - do {
> - if (blk_rq_sectors(req) > 1 &&
> - mg_wait(host, ATA_DRQ,
> - MG_TMAX_WAIT_WR_DRQ) != MG_ERR_NONE) {
> + rem--;
> + if (rem > 1 && mg_wait(host, ATA_DRQ,
> + MG_TMAX_WAIT_WR_DRQ) != MG_ERR_NONE) {
> + mg_bad_rw_intr(host);
> + return;
> + } else if (mg_wait(host, MG_STAT_READY,
> + MG_TMAX_WAIT_WR_DRQ) != MG_ERR_NONE) {
> mg_bad_rw_intr(host);
> return;
> }
> -
> - rem = mg_end_request(host, 0, MG_SECTOR_SIZE);
> - if (rem)
> - mg_write_one(host, req);
> -
> - outb(MG_CMD_WR_CONF,
> - (unsigned long)host->dev_base + MG_REG_COMMAND);
> - } while (rem);
> + } while (mg_end_request(host, 0, MG_SECTOR_SIZE));
> }
>
> static void mg_read_intr(struct mg_host *host)
>
> [ It is on top of my patch (http://lkml.org/lkml/2009/6/28/237), right?
>
Right. I missed the comments for your previous patch.
> I assume that both patches were verified with hardware and are ready
> to be merged upstream now? ]
>
Yes, tested. :)
---
Regards,
unsik Kim <[email protected]>
On Thu, Jul 23 2009, unsik Kim wrote:
> When last sector is written, ready bit of status register should be
> checked.
Added (with Barts ack), thanks!
--
Jens Axboe