[dm-devel] [PATCH] Use SCSI sense data in dm-mpath bio-end_io if available
Lars Marowsky-Bree
lmb at suse.de
Mon Apr 11 12:38:00 UTC 2005
Good morning Alasdair & list,
the attached two patches enable SCSI sense data to be available in the
bio-end_io path and use it in dm-mpath's hwhandler as well as dm-emc.c.
Please test and let us know the results.
Sincerely,
Lars Marowsky-Brée <lmb at suse.de>
--
High Availability & Clustering
SUSE Labs, Research and Development
SUSE LINUX Products GmbH - A Novell Business
-------------- next part --------------
From: Jens Axboe <axboe at suse.de>
Subject: Make SCSI sense data available in bio end_io path
Patch-mainline: 2.6.13
References: 62498
Make the sense data available in the bio end_io path on request.
Signed-off-by: Lars Marowsky-Bree <lmb at suse.de>
Signed-off-by: Jens Axboe <axboe at suse.de>
diff -urp -X /home/axboe/cdrom/exclude /opt/kernel/linux-2.6.5/drivers/block/ll_rw_blk.c linux-2.6.5/drivers/block/ll_rw_blk.c
--- /opt/kernel/linux-2.6.5/drivers/block/ll_rw_blk.c 2005-04-01 09:41:07.000000000 +0200
+++ linux-2.6.5/drivers/block/ll_rw_blk.c 2005-04-01 10:11:43.000000000 +0200
@@ -28,6 +28,7 @@
#include <linux/slab.h>
#include <linux/swap.h>
#include <linux/writeback.h>
+#include <linux/cdrom.h>
/*
* for max sense size
@@ -2989,6 +2990,7 @@ static int __end_that_request_first(stru
int nr_bytes)
{
int total_bytes, bio_nbytes, error, next_idx = 0;
+ struct request_sense *s = NULL;
struct bio *bio;
/*
@@ -2998,6 +3000,12 @@ static int __end_that_request_first(stru
if (end_io_error(uptodate))
error = !uptodate ? -EIO : uptodate;
+ if (req->sense && req->sense_len) {
+ s = req->sense;
+ if (!s->valid)
+ s = NULL;
+ }
+
/*
* for a REQ_BLOCK_PC request, we want to carry any eventual
* sense key with us all the way through
@@ -3023,6 +3031,9 @@ static int __end_that_request_first(stru
while ((bio = req->bio)) {
int nbytes;
+ if (s)
+ bio_set_sense(bio, s->sense_key, s->asc, s->ascq);
+
if (nr_bytes >= bio->bi_size) {
req->bio = bio->bi_next;
nbytes = bio->bi_size;
diff -urp -X /home/axboe/cdrom/exclude /opt/kernel/linux-2.6.5/drivers/scsi/scsi_lib.c linux-2.6.5/drivers/scsi/scsi_lib.c
--- /opt/kernel/linux-2.6.5/drivers/scsi/scsi_lib.c 2005-04-01 09:41:06.000000000 +0200
+++ linux-2.6.5/drivers/scsi/scsi_lib.c 2005-04-01 10:51:20.000000000 +0200
@@ -517,9 +517,21 @@ static struct scsi_cmnd *scsi_end_reques
{
request_queue_t *q = cmd->device->request_queue;
struct request *req = cmd->request;
+ int sense_override = 0;
unsigned long flags;
/*
+ * if room for sense wasn't supplied for this request, override with
+ * what we have stored for the duration of the end_io handling. this
+ * allows passing of sense to the block layer.
+ */
+ if (!req->sense && (cmd->sense_buffer[0] & 0x70)) {
+ req->sense = cmd->sense_buffer;
+ req->sense_len = 8 + cmd->sense_buffer[7];
+ sense_override = 1;
+ }
+
+ /*
* If there are blocks left over at the end, set up the command
* to queue the remainder of them.
*/
@@ -545,6 +557,9 @@ static struct scsi_cmnd *scsi_end_reques
}
}
+ if (sense_override)
+ req->sense = NULL;
+
add_disk_randomness(req->rq_disk);
spin_lock_irqsave(q->queue_lock, flags);
diff -urp -X /home/axboe/cdrom/exclude /opt/kernel/linux-2.6.5/fs/bio.c linux-2.6.5/fs/bio.c
--- /opt/kernel/linux-2.6.5/fs/bio.c 2005-04-01 09:41:14.000000000 +0200
+++ linux-2.6.5/fs/bio.c 2005-04-01 10:54:16.000000000 +0200
@@ -108,6 +108,7 @@ inline void bio_init(struct bio *bio)
bio->bi_bdev = NULL;
bio->bi_flags = 1 << BIO_UPTODATE;
bio->bi_rw = 0;
+ bio->bi_error = 0;
bio->bi_vcnt = 0;
bio->bi_idx = 0;
bio->bi_phys_segments = 0;
diff -urp -X /home/axboe/cdrom/exclude /opt/kernel/linux-2.6.5/include/linux/bio.h linux-2.6.5/include/linux/bio.h
--- /opt/kernel/linux-2.6.5/include/linux/bio.h 2005-04-01 09:41:08.000000000 +0200
+++ linux-2.6.5/include/linux/bio.h 2005-04-01 10:14:54.000000000 +0200
@@ -66,6 +66,7 @@ struct bio {
unsigned long bi_rw; /* bottom bits READ/WRITE,
* top bits priority
*/
+ unsigned int bi_error; /* -Exx or sense */
unsigned short bi_vcnt; /* how many bio_vec's */
unsigned short bi_idx; /* current index into bvl_vec */
@@ -211,6 +212,23 @@ struct bio {
*/
#define bio_get(bio) atomic_inc(&(bio)->bi_cnt)
+enum {
+ BIO_ERROR_ERRNO = 1,
+ BIO_ERROR_SENSE,
+};
+
+/*
+ * Extended error reporting. The upper 8 bits are flag values, the bottom
+ * 24 can be used for extended errors (such as sense).
+ */
+static inline void bio_set_sense(struct bio *bio, char key, char asc, char ascq)
+{
+ bio->bi_error = (BIO_ERROR_SENSE << 24) | (key << 16) | (asc << 8) | ascq;
+}
+
+#define bio_errno_valid(bio) ((bio)->bi_error & (BIO_ERROR_ERRNO << 24))
+#define bio_sense_valid(bio) ((bio)->bi_error & (BIO_ERROR_SENSE << 24))
+#define bio_sense_value(bio) ((bio)->bi_error & 0xffffff)
/*
* A bio_pair is used when we need to split a bio.
-------------- next part --------------
From: Lars Marowsky-Bree <lmb at suse.de>
Subject: Use SCSI sense data in dm-mpath bio end_io path
Patch-mainline: 2.6.13
Suse-bugzilla: 62498
Use the sense data in the dm-mpath hardware handlers.
Signed-off-by: Jens Axboe <axboe at suse.de>
Index: linux-2.6.5/drivers/md/dm-emc.c
===================================================================
--- linux-2.6.5.orig/drivers/md/dm-emc.c 2005-04-11 13:59:37.825222738 +0200
+++ linux-2.6.5/drivers/md/dm-emc.c 2005-04-11 14:14:04.772636876 +0200
@@ -290,12 +290,10 @@ static void emc_dtr(struct hw_handler *h
static unsigned emc_err(struct hw_handler *hwh, struct bio *bio)
{
- /* FIXME: Patch from axboe still missing */
-#if 0
int sense;
- if (bio->bi_error & BIO_SENSE) {
- sense = bio->bi_error & 0xffffff; /* sense key / asc / ascq */
+ if (bio_sense_valid(bio)) {
+ sense = bio_sense_value(bio); /* sense key / asc / ascq */
if (sense == 0x020403) {
/* LUN Not Ready - Manual Intervention Required
@@ -306,21 +304,20 @@ static unsigned emc_err(struct hw_handle
* progress, we should set FAIL_PATH too.
* This indicates we might have to do a SCSI
* inquiry in the end_io path. Ugh. */
- return MP_BYPASS_PG | MP_RETRY_IO;
+ return MP_BYPASS_PG;
} else if (sense == 0x052501) {
/* An array based copy is in progress. Do not
* fail the path, do not bypass to another PG,
* do not retry. Fail the IO immediately.
* (Actually this is the same conclusion as in
* the default handler, but lets make sure.) */
- return 0;
+ return MP_ERROR_IO;
} else if (sense == 0x062900) {
/* Unit Attention Code. This is the first IO
* to the new path, so just retry. */
- return MP_RETRY_IO;
+ return 0;
}
}
-#endif
/* Try default handler */
return dm_scsi_err_handler(hwh, bio);
Index: linux-2.6.5/drivers/md/dm-hw-handler.c
===================================================================
--- linux-2.6.5.orig/drivers/md/dm-hw-handler.c 2005-04-11 13:59:37.805225704 +0200
+++ linux-2.6.5/drivers/md/dm-hw-handler.c 2005-04-11 14:14:49.225050588 +0200
@@ -153,13 +153,12 @@ unsigned dm_scsi_err_handler(struct hw_h
{
int sense_key, asc, ascq;
-#if 0
- if (bio->bi_error & BIO_SENSE) {
+ if (bio_sense_valid(bio)) {
/* FIXME: This is just an initial guess. */
/* key / asc / ascq */
- sense_key = (bio->bi_error >> 16) & 0xff;
- asc = (bio->bi_error >> 8) & 0xff;
- ascq = bio->bi_error & 0xff;
+ sense_key = (bio_sense_value(bio) >> 16) & 0xff;
+ asc = (bio_sense_value(bio) >> 8) & 0xff;
+ ascq = bio_sense_value(bio) & 0xff;
switch (sense_key) {
/* This block as a whole comes from the device.
@@ -204,7 +203,6 @@ unsigned dm_scsi_err_handler(struct hw_h
return 0;
}
}
-#endif
/* We got no idea how to decode the other kinds of errors ->
* assume generic error condition. */
-------------- next part --------------
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