diff --git a/drivers/md/md.c b/drivers/md/md.c
index 7ae3c5a18001b437e3d43ef593e5342b8db1cfce..48217e8aa0ebef7d957e288dace9e5f6510437bf 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -215,6 +215,55 @@ struct bio *bio_clone_mddev(struct bio *bio, gfp_t gfp_mask,
}
EXPORT_SYMBOL_GPL(bio_clone_mddev);
+void md_trim_bio(struct bio *bio, int offset, int size)
+{
+ /* 'bio' is a cloned bio which we need to trim to match
+ * the given offset and size.
+ * This requires adjusting bi_sector, bi_size, and bi_io_vec
+ */
+ int i;
+ struct bio_vec *bvec;
+ int sofar = 0;
+
+ size <<= 9;
+ if (offset == 0 && size == bio->bi_size)
+ return;
+
+ bio->bi_sector += offset;
+ bio->bi_size = size;
+ offset <<= 9;
+ clear_bit(BIO_SEG_VALID, &bio->bi_flags);
+
+ while (bio->bi_idx < bio->bi_vcnt &&
+ bio->bi_io_vec[bio->bi_idx].bv_len <= offset) {
+ /* remove this whole bio_vec */
+ offset -= bio->bi_io_vec[bio->bi_idx].bv_len;
+ bio->bi_idx++;
+ }
+ if (bio->bi_idx < bio->bi_vcnt) {
+ bio->bi_io_vec[bio->bi_idx].bv_offset += offset;
+ bio->bi_io_vec[bio->bi_idx].bv_len -= offset;
+ }
+ /* avoid any complications with bi_idx being non-zero*/
+ if (bio->bi_idx) {
+ memmove(bio->bi_io_vec, bio->bi_io_vec+bio->bi_idx,
+ (bio->bi_vcnt - bio->bi_idx) * sizeof(struct bio_vec));
+ bio->bi_vcnt -= bio->bi_idx;
+ bio->bi_idx = 0;
+ }
+ /* Make sure vcnt and last bv are not too big */
+ bio_for_each_segment(bvec, bio, i) {
+ if (sofar + bvec->bv_len > size)
+ bvec->bv_len = size - sofar;
+ if (bvec->bv_len == 0) {
+ bio->bi_vcnt = i;
+ break;
+ }
+ sofar += bvec->bv_len;
+ }
+}
+EXPORT_SYMBOL_GPL(md_trim_bio);
+
/*
* We have a system wide 'event count' that is incremented
* on any 'interesting' event, and readers of /proc/mdstat
diff --git a/drivers/md/md.h b/drivers/md/md.h
index aea9e9ff8a33975480c0ac9aeb7f2452c1aa53e9..7c3192c0a29a1cbf4f728cb5e5c0bfb1c5fb5628 100644
--- a/drivers/md/md.h
+++ b/drivers/md/md.h
@@ -575,4 +575,5 @@ extern struct bio *bio_clone_mddev(struct bio *bio, gfp_t gfp_mask,
extern struct bio *bio_alloc_mddev(gfp_t gfp_mask, int nr_iovecs,
mddev_t *mddev);
extern int mddev_check_plugged(mddev_t *mddev);
+extern void md_trim_bio(struct bio *bio, int offset, int size);
#endif /* _MD_MD_H */
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index 8db311d7cddcd35079d6a3aaa413b0dea5e610b7..cc3939dc9e3d140b4b6f5145d00880acff81a5c5 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -41,11 +41,7 @@
#include "bitmap.h"
#define DEBUG 0
-#if DEBUG
-#define PRINTK(x...) printk(x)
-#else
-#define PRINTK(x...)
-#endif
+#define PRINTK(x...) do { if (DEBUG) printk(x); } while (0)
/*
* Number of guaranteed r1bios in case of extreme VM load:
@@ -177,12 +173,6 @@ static void free_r1bio(r1bio_t *r1_bio)
{
conf_t *conf = r1_bio->mddev->private;
- /*
- * Wake up any possible resync thread that waits for the device
- * to go idle.
- */
- allow_barrier(conf);
-
put_all_bios(conf, r1_bio);
mempool_free(r1_bio, conf->r1bio_pool);
}
@@ -223,6 +213,33 @@ static void reschedule_retry(r1bio_t *r1_bio)
* operation and are ready to return a success/failure code to the buffer
* cache layer.
*/
+static void call_bio_endio(r1bio_t *r1_bio)
+{
+ struct bio *bio = r1_bio->master_bio;
+ int done;
+ conf_t *conf = r1_bio->mddev->private;
+
+ if (bio->bi_phys_segments) {
+ unsigned long flags;
+ spin_lock_irqsave(&conf->device_lock, flags);
+ bio->bi_phys_segments--;
+ done = (bio->bi_phys_segments == 0);
+ spin_unlock_irqrestore(&conf->device_lock, flags);
+ } else
+ done = 1;
+
+ if (!test_bit(R1BIO_Uptodate, &r1_bio->state))
+ clear_bit(BIO_UPTODATE, &bio->bi_flags);
+ if (done) {
+ bio_endio(bio, 0);
+ /*
+ * Wake up any possible resync thread that waits for the device
+ * to go idle.
+ */
+ allow_barrier(conf);
+ }
+}
+
static void raid_end_bio_io(r1bio_t *r1_bio)
{
struct bio *bio = r1_bio->master_bio;
@@ -235,8 +252,7 @@ static void raid_end_bio_io(r1bio_t *r1_bio)
(unsigned long long) bio->bi_sector +
(bio->bi_size >> 9) - 1);
- bio_endio(bio,
- test_bit(R1BIO_Uptodate, &r1_bio->state) ? 0 : -EIO);
+ call_bio_endio(r1_bio);
}
free_r1bio(r1_bio);
}
@@ -295,6 +311,7 @@ static void raid1_end_read_request(struct bio *bio, int error)
bdevname(conf->mirrors[mirror].rdev->bdev,
b),
(unsigned long long)r1_bio->sector);
+ set_bit(R1BIO_ReadError, &r1_bio->state);
reschedule_retry(r1_bio);
}
@@ -381,7 +398,7 @@ static void raid1_end_write_request(struct bio *bio, int error)
(unsigned long long) mbio->bi_sector,
(unsigned long long) mbio->bi_sector +
(mbio->bi_size >> 9) - 1);
- bio_endio(mbio, 0);
+ call_bio_endio(r1_bio);
}
}
}
@@ -412,10 +429,11 @@ static void raid1_end_write_request(struct bio *bio, int error)
*
* The rdev for the device selected will have nr_pending incremented.
*/
-static int read_balance(conf_t *conf, r1bio_t *r1_bio)
+static int read_balance(conf_t *conf, r1bio_t *r1_bio, int *max_sectors)
{
const sector_t this_sector = r1_bio->sector;
- const int sectors = r1_bio->sectors;
+ int sectors;
+ int best_good_sectors;
int start_disk;
int best_disk;
int i;
@@ -430,8 +448,11 @@ static int read_balance(conf_t *conf, r1bio_t *r1_bio)
* We take the first readable disk when above the resync window.
*/
retry:
+ sectors = r1_bio->sectors;
best_disk = -1;
best_dist = MaxSector;
+ best_good_sectors = 0;
+
if (conf->mddev->recovery_cp < MaxSector &&
(this_sector + sectors >= conf->next_resync)) {
choose_first = 1;
@@ -443,6 +464,9 @@ static int read_balance(conf_t *conf, r1bio_t *r1_bio)
for (i = 0 ; i < conf->raid_disks ; i++) {
sector_t dist;
+ sector_t first_bad;
+ int bad_sectors;
+
int disk = start_disk + i;
if (disk >= conf->raid_disks)
disk -= conf->raid_disks;
@@ -465,6 +489,35 @@ static int read_balance(conf_t *conf, r1bio_t *r1_bio)
/* This is a reasonable device to use. It might
* even be best.
*/
+ if (is_badblock(rdev, this_sector, sectors,
+ &first_bad, &bad_sectors)) {
+ if (best_dist < MaxSector)
+ /* already have a better device */
+ continue;
+ if (first_bad <= this_sector) {
+ /* cannot read here. If this is the 'primary'
+ * device, then we must not read beyond
+ * bad_sectors from another device..
+ */
+ bad_sectors -= (this_sector - first_bad);
+ if (choose_first && sectors > bad_sectors)
+ sectors = bad_sectors;
+ if (best_good_sectors > sectors)
+ best_good_sectors = sectors;
+
+ } else {
+ sector_t good_sectors = first_bad - this_sector;
+ if (good_sectors > best_good_sectors) {
+ best_good_sectors = good_sectors;
+ best_disk = disk;
+ }
+ if (choose_first)
+ break;
+ }
+ continue;
+ } else
+ best_good_sectors = sectors;
+
dist = abs(this_sector - conf->mirrors[disk].head_position);
if (choose_first
/* Don't change to another disk for sequential reads */
@@ -493,10 +546,12 @@ static int read_balance(conf_t *conf, r1bio_t *r1_bio)
rdev_dec_pending(rdev, conf->mddev);
goto retry;
}
+ sectors = best_good_sectors;
conf->next_seq_sect = this_sector + sectors;
conf->last_used = best_disk;
}
rcu_read_unlock();
+ *max_sectors = sectors;
return best_disk;
}
@@ -763,11 +818,25 @@ static int make_request(mddev_t *mddev, struct bio * bio)
r1_bio->mddev = mddev;
r1_bio->sector = bio->bi_sector;
+ /* We might need to issue multiple reads to different
+ * devices if there are bad blocks around, so we keep
+ * track of the number of reads in bio->bi_phys_segments.
+ * If this is 0, there is only one r1_bio and no locking
+ * will be needed when requests complete. If it is
+ * non-zero, then it is the number of not-completed requests.
+ */
+ bio->bi_phys_segments = 0;
+ clear_bit(BIO_SEG_VALID, &bio->bi_flags);
+
if (rw == READ) {
/*
* read balancing logic:
*/
- int rdisk = read_balance(conf, r1_bio);
+ int max_sectors;
+ int rdisk;
+
+read_again:
+ rdisk = read_balance(conf, r1_bio, &max_sectors);
if (rdisk < 0) {
/* couldn't find anywhere to read from */
@@ -788,6 +857,8 @@ static int make_request(mddev_t *mddev, struct bio * bio)
r1_bio->read_disk = rdisk;
read_bio = bio_clone_mddev(bio, GFP_NOIO, mddev);
+ md_trim_bio(read_bio, r1_bio->sector - bio->bi_sector,
+ max_sectors);
r1_bio->bios[rdisk] = read_bio;
@@ -797,7 +868,38 @@ static int make_request(mddev_t *mddev, struct bio * bio)
read_bio->bi_rw = READ | do_sync;
read_bio->bi_private = r1_bio;
- generic_make_request(read_bio);
+ if (max_sectors < r1_bio->sectors) {
+ /* could not read all from this device, so we will
+ * need another r1_bio.
+ */
+ int sectors_handled;
+
+ sectors_handled = (r1_bio->sector + max_sectors
+ - bio->bi_sector);
+ r1_bio->sectors = max_sectors;
+ spin_lock_irq(&conf->device_lock);
+ if (bio->bi_phys_segments == 0)
+ bio->bi_phys_segments = 2;
+ else
+ bio->bi_phys_segments++;
+ spin_unlock_irq(&conf->device_lock);
+ /* Cannot call generic_make_request directly
+ * as that will be queued in __make_request
+ * and subsequent mempool_alloc might block waiting
+ * for it. So hand bio over to raid1d.
+ */
+ reschedule_retry(r1_bio);
+
+ r1_bio = mempool_alloc(conf->r1bio_pool, GFP_NOIO);
+
+ r1_bio->master_bio = bio;
+ r1_bio->sectors = (bio->bi_size >> 9) - sectors_handled;
+ r1_bio->state = 0;
+ r1_bio->mddev = mddev;
+ r1_bio->sector = bio->bi_sector + sectors_handled;
+ goto read_again;
+ } else
+ generic_make_request(read_bio);
return 0;
}
@@ -849,8 +951,6 @@ static int make_request(mddev_t *mddev, struct bio * bio)
goto retry_write;
}
- BUG_ON(targets == 0); /* we never fail the last device */
-
if (targets < conf->raid_disks) {
/* array is degraded, we will not clear the bitmap
* on I/O completion (see raid1_end_write_request) */
@@ -1425,7 +1525,7 @@ static void sync_request_write(mddev_t *mddev, r1bio_t *r1_bio)
*
* 1. Retries failed read operations on working mirrors.
* 2. Updates the raid superblock when problems encounter.
- * 3. Performs writes following reads for array syncronising.
+ * 3. Performs writes following reads for array synchronising.
*/
static void fix_read_error(conf_t *conf, int read_disk,
@@ -1448,9 +1548,14 @@ static void fix_read_error(conf_t *conf, int read_disk,
* which is the thread that might remove
* a device. If raid1d ever becomes multi-threaded....
*/
+ sector_t first_bad;
+ int bad_sectors;
+
rdev = conf->mirrors[d].rdev;
if (rdev &&
test_bit(In_sync, &rdev->flags) &&
+ is_badblock(rdev, sect, s,
+ &first_bad, &bad_sectors) == 0 &&
sync_page_io(rdev, sect, s<<9,
conf->tmppage, READ, false))
success = 1;
@@ -1546,9 +1651,11 @@ static void raid1d(mddev_t *mddev)
conf = mddev->private;
if (test_bit(R1BIO_IsSync, &r1_bio->state))
sync_request_write(mddev, r1_bio);
- else {
+ else if (test_bit(R1BIO_ReadError, &r1_bio->state)) {
int disk;
+ int max_sectors;
+ clear_bit(R1BIO_ReadError, &r1_bio->state);
/* we got a read error. Maybe the drive is bad. Maybe just
* the block and we can fix it.
* We freeze all other IO, and try reading the block from
@@ -1568,21 +1675,28 @@ static void raid1d(mddev_t *mddev)
conf->mirrors[r1_bio->read_disk].rdev);
bio = r1_bio->bios[r1_bio->read_disk];
- if ((disk=read_balance(conf, r1_bio)) == -1) {
+ bdevname(bio->bi_bdev, b);
+read_more:
+ disk = read_balance(conf, r1_bio, &max_sectors);
+ if (disk == -1) {
printk(KERN_ALERT "md/raid1:%s: %s: unrecoverable I/O"
" read error for block %llu\n",
- mdname(mddev),
- bdevname(bio->bi_bdev,b),
+ mdname(mddev), b,
(unsigned long long)r1_bio->sector);
raid_end_bio_io(r1_bio);
} else {
const unsigned long do_sync = r1_bio->master_bio->bi_rw & REQ_SYNC;
- r1_bio->bios[r1_bio->read_disk] =
- mddev->ro ? IO_BLOCKED : NULL;
+ if (bio) {
+ r1_bio->bios[r1_bio->read_disk] =
+ mddev->ro ? IO_BLOCKED : NULL;
+ bio_put(bio);
+ }
r1_bio->read_disk = disk;
- bio_put(bio);
bio = bio_clone_mddev(r1_bio->master_bio,
GFP_NOIO, mddev);
+ md_trim_bio(bio,
+ r1_bio->sector - bio->bi_sector,
+ max_sectors);
r1_bio->bios[r1_bio->read_disk] = bio;
rdev = conf->mirrors[disk].rdev;
printk_ratelimited(
@@ -1597,8 +1711,44 @@ static void raid1d(mddev_t *mddev)
bio->bi_end_io = raid1_end_read_request;
bio->bi_rw = READ | do_sync;
bio->bi_private = r1_bio;
- generic_make_request(bio);
+ if (max_sectors < r1_bio->sectors) {
+ /* Drat - have to split this up more */
+ struct bio *mbio = r1_bio->master_bio;
+ int sectors_handled =
+ r1_bio->sector + max_sectors
+ - mbio->bi_sector;
+ r1_bio->sectors = max_sectors;
+ spin_lock_irq(&conf->device_lock);
+ if (mbio->bi_phys_segments == 0)
+ mbio->bi_phys_segments = 2;
+ else
+ mbio->bi_phys_segments++;
+ spin_unlock_irq(&conf->device_lock);
+ generic_make_request(bio);
+ bio = NULL;
+
+ r1_bio = mempool_alloc(conf->r1bio_pool,
+ GFP_NOIO);
+
+ r1_bio->master_bio = mbio;
+ r1_bio->sectors = (mbio->bi_size >> 9)
+ - sectors_handled;
+ r1_bio->state = 0;
+ set_bit(R1BIO_ReadError,
+ &r1_bio->state);
+ r1_bio->mddev = mddev;
+ r1_bio->sector = mbio->bi_sector
+ + sectors_handled;
+
+ goto read_more;
+ } else
+ generic_make_request(bio);
}
+ } else {
+ /* just a partial read to be scheduled from separate
+ * context
+ */
+ generic_make_request(r1_bio->bios[r1_bio->read_disk]);
}
cond_resched();
}
diff --git a/drivers/md/raid1.h b/drivers/md/raid1.h
index 3cd18cfda2ad7f2760c91caa2db7f1f63f8ed617..aa6af37ca01b657202f48ef20a3e73c1f0c2c87a 100644
--- a/drivers/md/raid1.h
+++ b/drivers/md/raid1.h
@@ -123,6 +123,10 @@ struct r1bio_s {
#define R1BIO_IsSync 1
#define R1BIO_Degraded 2
#define R1BIO_BehindIO 3
+/* Set ReadError on bios that experience a readerror so that
+ * raid1d knows what to do with them.
+ */
+#define R1BIO_ReadError 4
/* For write-behind requests, we call bi_end_io when
* the last non-write-behind device completes, providing
* any write was successful. Otherwise we call when