| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Date: Wed, 8 Apr 2009 10:55:53 +0100
From: Wolfgang Mües <wolfgang.mues@...rswald.de>
To: Pierre Ossman <drzeus@...eus.cx>
Cc: "Andrew Morton" <akpm@...ux-foundation.org>,
"Matt Fleming" <matt@...sole-pimps.org>,
"David Brownell" <dbrownell@...rs.sourceforge.net>,
"Mike Frysinger" <vapier.adi@...il.com>,
linux-kernel@...r.kernel.org
Subject: [PATCH] mmc_spi: do propper retry managment in the block layer
From: Wolfgang Muees <wolfgang.mues@...rswald.de>
o This patch adds a propper retry managment for reading
and writing data blocks for mmc and mmc_spi. Blocks are
retransmitted 2 times in case of a transmission failure.
This patch was tested with induced transmission errors
by ESD pulses (and survived).
Signed-off-by: Wolfgang Muees <wolfgang.mues@...rswald.de>
---
diff -uprN 2_6_29_rc7_patch_wearout_speedup/drivers/mmc/card/block.c 2_6_29_rc7_patch_retries/drivers/mmc/card/block.c
--- 2_6_29_rc7_patch_wearout_speedup/drivers/mmc/card/block.c 2009-03-09 17:10:55.000000000 +0100
+++ 2_6_29_rc7_patch_retries/drivers/mmc/card/block.c 2009-04-08 11:19:55.000000000 +0200
@@ -230,12 +230,14 @@ static int mmc_blk_issue_rq(struct mmc_q
struct mmc_card *card = md->queue.card;
struct mmc_blk_request brq;
int ret = 1, disable_multi = 0;
+ int error_retry_count = 3;
mmc_claim_host(card->host);
do {
struct mmc_command cmd;
u32 readcmd, writecmd, status = 0;
+ int error;
memset(&brq, 0, sizeof(struct mmc_blk_request));
brq.mrq.cmd = &brq.cmd;
@@ -252,9 +254,9 @@ static int mmc_blk_issue_rq(struct mmc_q
brq.data.blocks = req->nr_sectors;
/*
- * After a read error, we redo the request one sector at a time
- * in order to accurately determine which sectors can be read
- * successfully.
+ * After a transmission error, we redo the request one sector
+ * at a time in order to accurately determine which sectors
+ * can be read/written successfully.
*/
if (disable_multi && brq.data.blocks > 1)
brq.data.blocks = 1;
@@ -262,10 +264,12 @@ static int mmc_blk_issue_rq(struct mmc_q
if (brq.data.blocks > 1) {
/* SPI multiblock writes terminate using a special
* token, not a STOP_TRANSMISSION request.
- */
- if (!mmc_host_is_spi(card->host)
- || rq_data_dir(req) == READ)
- brq.mrq.stop = &brq.stop;
+ * Here, this request is set for all types of
+ * hosts, so that we can use it in the lower
+ * layers if the data transfer stage has failed
+ * and the card is not able to accept the token.
+ */
+ brq.mrq.stop = &brq.stop;
readcmd = MMC_READ_MULTIPLE_BLOCK;
writecmd = MMC_WRITE_MULTIPLE_BLOCK;
} else {
@@ -312,20 +316,44 @@ static int mmc_blk_issue_rq(struct mmc_q
mmc_queue_bounce_post(mq);
- /*
- * Check for errors here, but don't jump to cmd_err
- * until later as we need to wait for the card to leave
- * programming mode even when things go wrong.
+ /* Check for all sort of errors which might be
+ * a transmission fault.
*/
- if (brq.cmd.error || brq.data.error || brq.stop.error) {
- if (brq.data.blocks > 1 && rq_data_dir(req) == READ) {
- /* Redo read one sector at a time */
- printk(KERN_WARNING "%s: retrying using single "
- "block read\n", req->rq_disk->disk_name);
- disable_multi = 1;
- continue;
- }
+ error = brq.cmd.error;
+ if (!error)
+ error = brq.data.error;
+ if (!error)
+ error = brq.stop.error;
+ /* Do retries for all sort of transmission errors */
+ switch (error) {
+ /* Card has not understand command. As we do only send
+ * valid commands, this must be a transmission error.
+ */
+ case -EPROTO:
+ /* CRC error */
+ case -EILSEQ:
+ /* Timeout, no answer. If we repeat the command,
+ * we do an overall slowdown and have good chances to
+ * complete the transfer.
+ */
+ case -ETIMEDOUT:
+ /* Invalid response. This is most likely a transmission
+ * error from card to host.
+ */
+ case -EINVAL:
+ error_retry_count -= 1;
+ disable_multi = 1;
+ printk(KERN_WARNING "%s: transmission error %d\n",
+ req->rq_disk->disk_name, error);
status = get_card_status(card, req);
+ if (error_retry_count > 0)
+ continue;
+ break;
+ case 0: /* no error: reset retry count for next block. */
+ error_retry_count = 3;
+ break;
+ default: /* unknown error: do error handling below */
+ break;
}
if (brq.cmd.error) {
@@ -384,18 +412,15 @@ static int mmc_blk_issue_rq(struct mmc_q
}
if (brq.cmd.error || brq.stop.error || brq.data.error) {
- if (rq_data_dir(req) == READ) {
- /*
- * After an error, we redo I/O one sector at a
- * time, so we only reach here after trying to
- * read a single sector.
- */
- spin_lock_irq(&md->lock);
- ret = __blk_end_request(req, -EIO, brq.data.blksz);
- spin_unlock_irq(&md->lock);
- continue;
- }
- goto cmd_err;
+ /*
+ * After an error, we redo I/O one sector at a
+ * time, so we only reach here after trying to
+ * read/write a single sector.
+ */
+ spin_lock_irq(&md->lock);
+ ret = __blk_end_request(req, -EIO, brq.data.blksz);
+ spin_unlock_irq(&md->lock);
+ continue;
}
/*
diff -uprN 2_6_29_rc7_patch_wearout_speedup/drivers/mmc/host/mmc_spi.c 2_6_29_rc7_patch_retries/drivers/mmc/host/mmc_spi.c
--- 2_6_29_rc7_patch_wearout_speedup/drivers/mmc/host/mmc_spi.c 2009-04-08 11:11:20.000000000 +0200
+++ 2_6_29_rc7_patch_retries/drivers/mmc/host/mmc_spi.c 2009-04-08 11:25:04.000000000 +0200
@@ -742,22 +742,24 @@ mmc_spi_writeblock(struct mmc_spi_host *
if (status != 0) {
dev_dbg(&spi->dev, "write error %02x (%d)\n",
scratch->status[0], status);
- return status;
+ } else {
+ t->tx_buf += t->len;
+ if (host->dma_dev)
+ t->tx_dma += t->len;
}
- t->tx_buf += t->len;
- if (host->dma_dev)
- t->tx_dma += t->len;
-
/* Return when not busy. If we didn't collect that status yet,
* we'll need some more I/O.
*/
for (i = 4; i < sizeof(scratch->status); i++) {
/* card is non-busy if the most recent bit is 1 */
if (scratch->status[i] & 0x01)
- return 0;
+ return status;
}
- return mmc_spi_wait_unbusy(host, timeout);
+ i = mmc_spi_wait_unbusy(host, timeout);
+ if (!status)
+ status = i;
+ return status;
}
/*
@@ -1086,7 +1088,15 @@ static void mmc_spi_request(struct mmc_h
status = mmc_spi_command_send(host, mrq, mrq->cmd, mrq->data != NULL);
if (status == 0 && mrq->data) {
mmc_spi_data_do(host, mrq->cmd, mrq->data, mrq->data->blksz);
- if (mrq->stop)
+ /* filter-out the stop command for multiblock writes,
+ * only if the data stage has no transmission error.
+ * If the data stage has a transmission error, send the
+ * STOP command because there is a great chance that the
+ * SPI stop token was not accepted by the card.
+ */
+ if (mrq->stop &&
+ ((mrq->data->flags & MMC_DATA_READ)
+ || mrq->data->error))
status = mmc_spi_command_send(host, mrq, mrq->stop, 0);
else
mmc_cs_off(host);
---
regards
i. A. Wolfgang Mües
--
Auerswald GmbH & Co. KG
Hardware Development
Telefon: +49 (0)5306 9219 0
Telefax: +49 (0)5306 9219 94
E-Mail: Wolfgang.Mues@...rswald.de
Web: http://www.auerswald.de
--------------------------------------------------------------
Auerswald GmbH & Co. KG, Vor den Grashöfen 1, 38162 Cremlingen
Registriert beim AG Braunschweig HRA 13289
p.h.G Auerswald Geschäftsführungsges. mbH
Registriert beim AG Braunschweig HRB 7463
Geschäftsführer: Dipl-Ing. Gerhard Auerswald
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists