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-rw-r--r--drivers/md/raid1.c726
1 files changed, 504 insertions, 222 deletions
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index 229d7b2..a06ff91 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -47,10 +47,11 @@
*/
#define NR_RAID1_BIOS 256
-static mdk_personality_t raid1_personality;
static void unplug_slaves(mddev_t *mddev);
+static void allow_barrier(conf_t *conf);
+static void lower_barrier(conf_t *conf);
static void * r1bio_pool_alloc(gfp_t gfp_flags, void *data)
{
@@ -59,10 +60,8 @@ static void * r1bio_pool_alloc(gfp_t gfp_flags, void *data)
int size = offsetof(r1bio_t, bios[pi->raid_disks]);
/* allocate a r1bio with room for raid_disks entries in the bios array */
- r1_bio = kmalloc(size, gfp_flags);
- if (r1_bio)
- memset(r1_bio, 0, size);
- else
+ r1_bio = kzalloc(size, gfp_flags);
+ if (!r1_bio)
unplug_slaves(pi->mddev);
return r1_bio;
@@ -104,15 +103,30 @@ static void * r1buf_pool_alloc(gfp_t gfp_flags, void *data)
}
/*
* Allocate RESYNC_PAGES data pages and attach them to
- * the first bio;
+ * the first bio.
+ * If this is a user-requested check/repair, allocate
+ * RESYNC_PAGES for each bio.
*/
- bio = r1_bio->bios[0];
- for (i = 0; i < RESYNC_PAGES; i++) {
- page = alloc_page(gfp_flags);
- if (unlikely(!page))
- goto out_free_pages;
-
- bio->bi_io_vec[i].bv_page = page;
+ if (test_bit(MD_RECOVERY_REQUESTED, &pi->mddev->recovery))
+ j = pi->raid_disks;
+ else
+ j = 1;
+ while(j--) {
+ bio = r1_bio->bios[j];
+ for (i = 0; i < RESYNC_PAGES; i++) {
+ page = alloc_page(gfp_flags);
+ if (unlikely(!page))
+ goto out_free_pages;
+
+ bio->bi_io_vec[i].bv_page = page;
+ }
+ }
+ /* If not user-requests, copy the page pointers to all bios */
+ if (!test_bit(MD_RECOVERY_REQUESTED, &pi->mddev->recovery)) {
+ for (i=0; i<RESYNC_PAGES ; i++)
+ for (j=1; j<pi->raid_disks; j++)
+ r1_bio->bios[j]->bi_io_vec[i].bv_page =
+ r1_bio->bios[0]->bi_io_vec[i].bv_page;
}
r1_bio->master_bio = NULL;
@@ -120,8 +134,10 @@ static void * r1buf_pool_alloc(gfp_t gfp_flags, void *data)
return r1_bio;
out_free_pages:
- for ( ; i > 0 ; i--)
- __free_page(bio->bi_io_vec[i-1].bv_page);
+ for (i=0; i < RESYNC_PAGES ; i++)
+ for (j=0 ; j < pi->raid_disks; j++)
+ safe_put_page(r1_bio->bios[j]->bi_io_vec[i].bv_page);
+ j = -1;
out_free_bio:
while ( ++j < pi->raid_disks )
bio_put(r1_bio->bios[j]);
@@ -132,14 +148,16 @@ out_free_bio:
static void r1buf_pool_free(void *__r1_bio, void *data)
{
struct pool_info *pi = data;
- int i;
+ int i,j;
r1bio_t *r1bio = __r1_bio;
- struct bio *bio = r1bio->bios[0];
- for (i = 0; i < RESYNC_PAGES; i++) {
- __free_page(bio->bi_io_vec[i].bv_page);
- bio->bi_io_vec[i].bv_page = NULL;
- }
+ for (i = 0; i < RESYNC_PAGES; i++)
+ for (j = pi->raid_disks; j-- ;) {
+ if (j == 0 ||
+ r1bio->bios[j]->bi_io_vec[i].bv_page !=
+ r1bio->bios[0]->bi_io_vec[i].bv_page)
+ safe_put_page(r1bio->bios[j]->bi_io_vec[i].bv_page);
+ }
for (i=0 ; i < pi->raid_disks; i++)
bio_put(r1bio->bios[i]);
@@ -152,7 +170,7 @@ static void put_all_bios(conf_t *conf, r1bio_t *r1_bio)
for (i = 0; i < conf->raid_disks; i++) {
struct bio **bio = r1_bio->bios + i;
- if (*bio)
+ if (*bio && *bio != IO_BLOCKED)
bio_put(*bio);
*bio = NULL;
}
@@ -160,20 +178,13 @@ static void put_all_bios(conf_t *conf, r1bio_t *r1_bio)
static inline void free_r1bio(r1bio_t *r1_bio)
{
- unsigned long flags;
-
conf_t *conf = mddev_to_conf(r1_bio->mddev);
/*
* Wake up any possible resync thread that waits for the device
* to go idle.
*/
- spin_lock_irqsave(&conf->resync_lock, flags);
- if (!--conf->nr_pending) {
- wake_up(&conf->wait_idle);
- wake_up(&conf->wait_resume);
- }
- spin_unlock_irqrestore(&conf->resync_lock, flags);
+ allow_barrier(conf);
put_all_bios(conf, r1_bio);
mempool_free(r1_bio, conf->r1bio_pool);
@@ -182,22 +193,17 @@ static inline void free_r1bio(r1bio_t *r1_bio)
static inline void put_buf(r1bio_t *r1_bio)
{
conf_t *conf = mddev_to_conf(r1_bio->mddev);
- unsigned long flags;
+ int i;
- mempool_free(r1_bio, conf->r1buf_pool);
+ for (i=0; i<conf->raid_disks; i++) {
+ struct bio *bio = r1_bio->bios[i];
+ if (bio->bi_end_io)
+ rdev_dec_pending(conf->mirrors[i].rdev, r1_bio->mddev);
+ }
- spin_lock_irqsave(&conf->resync_lock, flags);
- if (!conf->barrier)
- BUG();
- --conf->barrier;
- wake_up(&conf->wait_resume);
- wake_up(&conf->wait_idle);
+ mempool_free(r1_bio, conf->r1buf_pool);
- if (!--conf->nr_pending) {
- wake_up(&conf->wait_idle);
- wake_up(&conf->wait_resume);
- }
- spin_unlock_irqrestore(&conf->resync_lock, flags);
+ lower_barrier(conf);
}
static void reschedule_retry(r1bio_t *r1_bio)
@@ -208,8 +214,10 @@ static void reschedule_retry(r1bio_t *r1_bio)
spin_lock_irqsave(&conf->device_lock, flags);
list_add(&r1_bio->retry_list, &conf->retry_list);
+ conf->nr_queued ++;
spin_unlock_irqrestore(&conf->device_lock, flags);
+ wake_up(&conf->wait_barrier);
md_wakeup_thread(mddev->thread);
}
@@ -261,9 +269,9 @@ static int raid1_end_read_request(struct bio *bio, unsigned int bytes_done, int
/*
* this branch is our 'one mirror IO has finished' event handler:
*/
- if (!uptodate)
- md_error(r1_bio->mddev, conf->mirrors[mirror].rdev);
- else
+ update_head_pos(mirror, r1_bio);
+
+ if (uptodate || conf->working_disks <= 1) {
/*
* Set R1BIO_Uptodate in our master bio, so that
* we will return a good error code for to the higher
@@ -273,16 +281,11 @@ static int raid1_end_read_request(struct bio *bio, unsigned int bytes_done, int
* user-side. So if something waits for IO, then it will
* wait for the 'master' bio.
*/
- set_bit(R1BIO_Uptodate, &r1_bio->state);
-
- update_head_pos(mirror, r1_bio);
+ if (uptodate)
+ set_bit(R1BIO_Uptodate, &r1_bio->state);
- /*
- * we have only one bio on the read side
- */
- if (uptodate)
raid_end_bio_io(r1_bio);
- else {
+ } else {
/*
* oops, read error:
*/
@@ -378,7 +381,7 @@ static int raid1_end_write_request(struct bio *bio, unsigned int bytes_done, int
/* free extra copy of the data pages */
int i = bio->bi_vcnt;
while (i--)
- __free_page(bio->bi_io_vec[i].bv_page);
+ safe_put_page(bio->bi_io_vec[i].bv_page);
}
/* clear the bitmap if all writes complete successfully */
bitmap_endwrite(r1_bio->mddev->bitmap, r1_bio->sector,
@@ -433,11 +436,13 @@ static int read_balance(conf_t *conf, r1bio_t *r1_bio)
new_disk = 0;
for (rdev = rcu_dereference(conf->mirrors[new_disk].rdev);
+ r1_bio->bios[new_disk] == IO_BLOCKED ||
!rdev || !test_bit(In_sync, &rdev->flags)
|| test_bit(WriteMostly, &rdev->flags);
rdev = rcu_dereference(conf->mirrors[++new_disk].rdev)) {
- if (rdev && test_bit(In_sync, &rdev->flags))
+ if (rdev && test_bit(In_sync, &rdev->flags) &&
+ r1_bio->bios[new_disk] != IO_BLOCKED)
wonly_disk = new_disk;
if (new_disk == conf->raid_disks - 1) {
@@ -451,11 +456,13 @@ static int read_balance(conf_t *conf, r1bio_t *r1_bio)
/* make sure the disk is operational */
for (rdev = rcu_dereference(conf->mirrors[new_disk].rdev);
+ r1_bio->bios[new_disk] == IO_BLOCKED ||
!rdev || !test_bit(In_sync, &rdev->flags) ||
test_bit(WriteMostly, &rdev->flags);
rdev = rcu_dereference(conf->mirrors[new_disk].rdev)) {
- if (rdev && test_bit(In_sync, &rdev->flags))
+ if (rdev && test_bit(In_sync, &rdev->flags) &&
+ r1_bio->bios[new_disk] != IO_BLOCKED)
wonly_disk = new_disk;
if (new_disk <= 0)
@@ -492,7 +499,7 @@ static int read_balance(conf_t *conf, r1bio_t *r1_bio)
rdev = rcu_dereference(conf->mirrors[disk].rdev);
- if (!rdev ||
+ if (!rdev || r1_bio->bios[disk] == IO_BLOCKED ||
!test_bit(In_sync, &rdev->flags) ||
test_bit(WriteMostly, &rdev->flags))
continue;
@@ -520,7 +527,7 @@ static int read_balance(conf_t *conf, r1bio_t *r1_bio)
/* cannot risk returning a device that failed
* before we inc'ed nr_pending
*/
- atomic_dec(&rdev->nr_pending);
+ rdev_dec_pending(rdev, conf->mddev);
goto retry;
}
conf->next_seq_sect = this_sector + sectors;
@@ -593,42 +600,119 @@ static int raid1_issue_flush(request_queue_t *q, struct gendisk *disk,
return ret;
}
-/*
- * Throttle resync depth, so that we can both get proper overlapping of
- * requests, but are still able to handle normal requests quickly.
+/* Barriers....
+ * Sometimes we need to suspend IO while we do something else,
+ * either some resync/recovery, or reconfigure the array.
+ * To do this we raise a 'barrier'.
+ * The 'barrier' is a counter that can be raised multiple times
+ * to count how many activities are happening which preclude
+ * normal IO.
+ * We can only raise the barrier if there is no pending IO.
+ * i.e. if nr_pending == 0.
+ * We choose only to raise the barrier if no-one is waiting for the
+ * barrier to go down. This means that as soon as an IO request
+ * is ready, no other operations which require a barrier will start
+ * until the IO request has had a chance.
+ *
+ * So: regular IO calls 'wait_barrier'. When that returns there
+ * is no backgroup IO happening, It must arrange to call
+ * allow_barrier when it has finished its IO.
+ * backgroup IO calls must call raise_barrier. Once that returns
+ * there is no normal IO happeing. It must arrange to call
+ * lower_barrier when the particular background IO completes.
*/
#define RESYNC_DEPTH 32
-static void device_barrier(conf_t *conf, sector_t sect)
+static void raise_barrier(conf_t *conf)
{
spin_lock_irq(&conf->resync_lock);
- wait_event_lock_irq(conf->wait_idle, !waitqueue_active(&conf->wait_resume),
- conf->resync_lock, raid1_unplug(conf->mddev->queue));
-
- if (!conf->barrier++) {
- wait_event_lock_irq(conf->wait_idle, !conf->nr_pending,
- conf->resync_lock, raid1_unplug(conf->mddev->queue));
- if (conf->nr_pending)
- BUG();
+
+ /* Wait until no block IO is waiting */
+ wait_event_lock_irq(conf->wait_barrier, !conf->nr_waiting,
+ conf->resync_lock,
+ raid1_unplug(conf->mddev->queue));
+
+ /* block any new IO from starting */
+ conf->barrier++;
+
+ /* No wait for all pending IO to complete */
+ wait_event_lock_irq(conf->wait_barrier,
+ !conf->nr_pending && conf->barrier < RESYNC_DEPTH,
+ conf->resync_lock,
+ raid1_unplug(conf->mddev->queue));
+
+ spin_unlock_irq(&conf->resync_lock);
+}
+
+static void lower_barrier(conf_t *conf)
+{
+ unsigned long flags;
+ spin_lock_irqsave(&conf->resync_lock, flags);
+ conf->barrier--;
+ spin_unlock_irqrestore(&conf->resync_lock, flags);
+ wake_up(&conf->wait_barrier);
+}
+
+static void wait_barrier(conf_t *conf)
+{
+ spin_lock_irq(&conf->resync_lock);
+ if (conf->barrier) {
+ conf->nr_waiting++;
+ wait_event_lock_irq(conf->wait_barrier, !conf->barrier,
+ conf->resync_lock,
+ raid1_unplug(conf->mddev->queue));
+ conf->nr_waiting--;
}
- wait_event_lock_irq(conf->wait_resume, conf->barrier < RESYNC_DEPTH,
- conf->resync_lock, raid1_unplug(conf->mddev->queue));
- conf->next_resync = sect;
+ conf->nr_pending++;
+ spin_unlock_irq(&conf->resync_lock);
+}
+
+static void allow_barrier(conf_t *conf)
+{
+ unsigned long flags;
+ spin_lock_irqsave(&conf->resync_lock, flags);
+ conf->nr_pending--;
+ spin_unlock_irqrestore(&conf->resync_lock, flags);
+ wake_up(&conf->wait_barrier);
+}
+
+static void freeze_array(conf_t *conf)
+{
+ /* stop syncio and normal IO and wait for everything to
+ * go quite.
+ * We increment barrier and nr_waiting, and then
+ * wait until barrier+nr_pending match nr_queued+2
+ */
+ spin_lock_irq(&conf->resync_lock);
+ conf->barrier++;
+ conf->nr_waiting++;
+ wait_event_lock_irq(conf->wait_barrier,
+ conf->barrier+conf->nr_pending == conf->nr_queued+2,
+ conf->resync_lock,
+ raid1_unplug(conf->mddev->queue));
+ spin_unlock_irq(&conf->resync_lock);
+}
+static void unfreeze_array(conf_t *conf)
+{
+ /* reverse the effect of the freeze */
+ spin_lock_irq(&conf->resync_lock);
+ conf->barrier--;
+ conf->nr_waiting--;
+ wake_up(&conf->wait_barrier);
spin_unlock_irq(&conf->resync_lock);
}
+
/* duplicate the data pages for behind I/O */
static struct page **alloc_behind_pages(struct bio *bio)
{
int i;
struct bio_vec *bvec;
- struct page **pages = kmalloc(bio->bi_vcnt * sizeof(struct page *),
+ struct page **pages = kzalloc(bio->bi_vcnt * sizeof(struct page *),
GFP_NOIO);
if (unlikely(!pages))
goto do_sync_io;
- memset(pages, 0, bio->bi_vcnt * sizeof(struct page *));
-
bio_for_each_segment(bvec, bio, i) {
pages[i] = alloc_page(GFP_NOIO);
if (unlikely(!pages[i]))
@@ -644,7 +728,7 @@ static struct page **alloc_behind_pages(struct bio *bio)
do_sync_io:
if (pages)
for (i = 0; i < bio->bi_vcnt && pages[i]; i++)
- __free_page(pages[i]);
+ put_page(pages[i]);
kfree(pages);
PRINTK("%dB behind alloc failed, doing sync I/O\n", bio->bi_size);
return NULL;
@@ -678,10 +762,7 @@ static int make_request(request_queue_t *q, struct bio * bio)
*/
md_write_start(mddev, bio); /* wait on superblock update early */
- spin_lock_irq(&conf->resync_lock);
- wait_event_lock_irq(conf->wait_resume, !conf->barrier, conf->resync_lock, );
- conf->nr_pending++;
- spin_unlock_irq(&conf->resync_lock);
+ wait_barrier(conf);
disk_stat_inc(mddev->gendisk, ios[rw]);
disk_stat_add(mddev->gendisk, sectors[rw], bio_sectors(bio));
@@ -749,7 +830,7 @@ static int make_request(request_queue_t *q, struct bio * bio)
!test_bit(Faulty, &rdev->flags)) {
atomic_inc(&rdev->nr_pending);
if (test_bit(Faulty, &rdev->flags)) {
- atomic_dec(&rdev->nr_pending);
+ rdev_dec_pending(rdev, mddev);
r1_bio->bios[i] = NULL;
} else
r1_bio->bios[i] = bio;
@@ -909,13 +990,8 @@ static void print_conf(conf_t *conf)
static void close_sync(conf_t *conf)
{
- spin_lock_irq(&conf->resync_lock);
- wait_event_lock_irq(conf->wait_resume, !conf->barrier,
- conf->resync_lock, raid1_unplug(conf->mddev->queue));
- spin_unlock_irq(&conf->resync_lock);
-
- if (conf->barrier) BUG();
- if (waitqueue_active(&conf->wait_idle)) BUG();
+ wait_barrier(conf);
+ allow_barrier(conf);
mempool_destroy(conf->r1buf_pool);
conf->r1buf_pool = NULL;
@@ -1015,28 +1091,27 @@ abort:
static int end_sync_read(struct bio *bio, unsigned int bytes_done, int error)
{
- int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
r1bio_t * r1_bio = (r1bio_t *)(bio->bi_private);
- conf_t *conf = mddev_to_conf(r1_bio->mddev);
+ int i;
if (bio->bi_size)
return 1;
- if (r1_bio->bios[r1_bio->read_disk] != bio)
- BUG();
- update_head_pos(r1_bio->read_disk, r1_bio);
+ for (i=r1_bio->mddev->raid_disks; i--; )
+ if (r1_bio->bios[i] == bio)
+ break;
+ BUG_ON(i < 0);
+ update_head_pos(i, r1_bio);
/*
* we have read a block, now it needs to be re-written,
* or re-read if the read failed.
* We don't do much here, just schedule handling by raid1d
*/
- if (!uptodate) {
- md_error(r1_bio->mddev,
- conf->mirrors[r1_bio->read_disk].rdev);
- } else
+ if (test_bit(BIO_UPTODATE, &bio->bi_flags))
set_bit(R1BIO_Uptodate, &r1_bio->state);
- rdev_dec_pending(conf->mirrors[r1_bio->read_disk].rdev, conf->mddev);
- reschedule_retry(r1_bio);
+
+ if (atomic_dec_and_test(&r1_bio->remaining))
+ reschedule_retry(r1_bio);
return 0;
}
@@ -1066,7 +1141,6 @@ static int end_sync_write(struct bio *bio, unsigned int bytes_done, int error)
md_done_sync(mddev, r1_bio->sectors, uptodate);
put_buf(r1_bio);
}
- rdev_dec_pending(conf->mirrors[mirror].rdev, mddev);
return 0;
}
@@ -1079,34 +1153,173 @@ static void sync_request_write(mddev_t *mddev, r1bio_t *r1_bio)
bio = r1_bio->bios[r1_bio->read_disk];
-/*
- if (r1_bio->sector == 0) printk("First sync write startss\n");
-*/
- /*
- * schedule writes
- */
+
+ if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) {
+ /* We have read all readable devices. If we haven't
+ * got the block, then there is no hope left.
+ * If we have, then we want to do a comparison
+ * and skip the write if everything is the same.
+ * If any blocks failed to read, then we need to
+ * attempt an over-write
+ */
+ int primary;
+ if (!test_bit(R1BIO_Uptodate, &r1_bio->state)) {
+ for (i=0; i<mddev->raid_disks; i++)
+ if (r1_bio->bios[i]->bi_end_io == end_sync_read)
+ md_error(mddev, conf->mirrors[i].rdev);
+
+ md_done_sync(mddev, r1_bio->sectors, 1);
+ put_buf(r1_bio);
+ return;
+ }
+ for (primary=0; primary<mddev->raid_disks; primary++)
+ if (r1_bio->bios[primary]->bi_end_io == end_sync_read &&
+ test_bit(BIO_UPTODATE, &r1_bio->bios[primary]->bi_flags)) {
+ r1_bio->bios[primary]->bi_end_io = NULL;
+ rdev_dec_pending(conf->mirrors[primary].rdev, mddev);
+ break;
+ }
+ r1_bio->read_disk = primary;
+ for (i=0; i<mddev->raid_disks; i++)
+ if (r1_bio->bios[i]->bi_end_io == end_sync_read &&
+ test_bit(BIO_UPTODATE, &r1_bio->bios[i]->bi_flags)) {
+ int j;
+ int vcnt = r1_bio->sectors >> (PAGE_SHIFT- 9);
+ struct bio *pbio = r1_bio->bios[primary];
+ struct bio *sbio = r1_bio->bios[i];
+ for (j = vcnt; j-- ; )
+ if (memcmp(page_address(pbio->bi_io_vec[j].bv_page),
+ page_address(sbio->bi_io_vec[j].bv_page),
+ PAGE_SIZE))
+ break;
+ if (j >= 0)
+ mddev->resync_mismatches += r1_bio->sectors;
+ if (j < 0 || test_bit(MD_RECOVERY_CHECK, &mddev->recovery)) {
+ sbio->bi_end_io = NULL;
+ rdev_dec_pending(conf->mirrors[i].rdev, mddev);
+ } else {
+ /* fixup the bio for reuse */
+ sbio->bi_vcnt = vcnt;
+ sbio->bi_size = r1_bio->sectors << 9;
+ sbio->bi_idx = 0;
+ sbio->bi_phys_segments = 0;
+ sbio->bi_hw_segments = 0;
+ sbio->bi_hw_front_size = 0;
+ sbio->bi_hw_back_size = 0;
+ sbio->bi_flags &= ~(BIO_POOL_MASK - 1);
+ sbio->bi_flags |= 1 << BIO_UPTODATE;
+ sbio->bi_next = NULL;
+ sbio->bi_sector = r1_bio->sector +
+ conf->mirrors[i].rdev->data_offset;
+ sbio->bi_bdev = conf->mirrors[i].rdev->bdev;
+ }
+ }
+ }
if (!test_bit(R1BIO_Uptodate, &r1_bio->state)) {
- /*
- * There is no point trying a read-for-reconstruct as
- * reconstruct is about to be aborted
+ /* ouch - failed to read all of that.
+ * Try some synchronous reads of other devices to get
+ * good data, much like with normal read errors. Only
+ * read into the pages we already have so they we don't
+ * need to re-issue the read request.
+ * We don't need to freeze the array, because being in an
+ * active sync request, there is no normal IO, and
+ * no overlapping syncs.
*/
- char b[BDEVNAME_SIZE];
- printk(KERN_ALERT "raid1: %s: unrecoverable I/O read error"
- " for block %llu\n",
- bdevname(bio->bi_bdev,b),
- (unsigned long long)r1_bio->sector);
- md_done_sync(mddev, r1_bio->sectors, 0);
- put_buf(r1_bio);
- return;
+ sector_t sect = r1_bio->sector;
+ int sectors = r1_bio->sectors;
+ int idx = 0;
+
+ while(sectors) {
+ int s = sectors;
+ int d = r1_bio->read_disk;
+ int success = 0;
+ mdk_rdev_t *rdev;
+
+ if (s > (PAGE_SIZE>>9))
+ s = PAGE_SIZE >> 9;
+ do {
+ if (r1_bio->bios[d]->bi_end_io == end_sync_read) {
+ rdev = conf->mirrors[d].rdev;
+ if (sync_page_io(rdev->bdev,
+ sect + rdev->data_offset,
+ s<<9,
+ bio->bi_io_vec[idx].bv_page,
+ READ)) {
+ success = 1;
+ break;
+ }
+ }
+ d++;
+ if (d == conf->raid_disks)
+ d = 0;
+ } while (!success && d != r1_bio->read_disk);
+
+ if (success) {
+ int start = d;
+ /* write it back and re-read */
+ set_bit(R1BIO_Uptodate, &r1_bio->state);
+ while (d != r1_bio->read_disk) {
+ if (d == 0)
+ d = conf->raid_disks;
+ d--;
+ if (r1_bio->bios[d]->bi_end_io != end_sync_read)
+ continue;
+ rdev = conf->mirrors[d].rdev;
+ atomic_add(s, &rdev->corrected_errors);
+ if (sync_page_io(rdev->bdev,
+ sect + rdev->data_offset,
+ s<<9,
+ bio->bi_io_vec[idx].bv_page,
+ WRITE) == 0)
+ md_error(mddev, rdev);
+ }
+ d = start;
+ while (d != r1_bio->read_disk) {
+ if (d == 0)
+ d = conf->raid_disks;
+ d--;
+ if (r1_bio->bios[d]->bi_end_io != end_sync_read)
+ continue;
+ rdev = conf->mirrors[d].rdev;
+ if (sync_page_io(rdev->bdev,
+ sect + rdev->data_offset,
+ s<<9,
+ bio->bi_io_vec[idx].bv_page,
+ READ) == 0)
+ md_error(mddev, rdev);
+ }
+ } else {
+ char b[BDEVNAME_SIZE];
+ /* Cannot read from anywhere, array is toast */
+ md_error(mddev, conf->mirrors[r1_bio->read_disk].rdev);
+ printk(KERN_ALERT "raid1: %s: unrecoverable I/O read error"
+ " for block %llu\n",
+ bdevname(bio->bi_bdev,b),
+ (unsigned long long)r1_bio->sector);
+ md_done_sync(mddev, r1_bio->sectors, 0);
+ put_buf(r1_bio);
+ return;
+ }
+ sectors -= s;
+ sect += s;
+ idx ++;
+ }
}
+ /*
+ * schedule writes
+ */
atomic_set(&r1_bio->remaining, 1);
for (i = 0; i < disks ; i++) {
wbio = r1_bio->bios[i];
- if (wbio->bi_end_io != end_sync_write)
+ if (wbio->bi_end_io == NULL ||
+ (wbio->bi_end_io == end_sync_read &&
+ (i == r1_bio->read_disk ||
+ !test_bit(MD_RECOVERY_SYNC, &mddev->recovery))))
continue;
- atomic_inc(&conf->mirrors[i].rdev->nr_pending);
+ wbio->bi_rw = WRITE;
+ wbio->bi_end_io = end_sync_write;
atomic_inc(&r1_bio->remaining);
md_sync_acct(conf->mirrors[i].rdev->bdev, wbio->bi_size >> 9);
@@ -1167,6 +1380,7 @@ static void raid1d(mddev_t *mddev)
break;
r1_bio = list_entry(head->prev, r1bio_t, retry_list);
list_del(head->prev);
+ conf->nr_queued--;
spin_unlock_irqrestore(&conf->device_lock, flags);
mddev = r1_bio->mddev;
@@ -1206,6 +1420,86 @@ static void raid1d(mddev_t *mddev)
}
} else {
int disk;
+
+ /* 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
+ * other devices. When we find one, we re-write
+ * and check it that fixes the read error.
+ * This is all done synchronously while the array is
+ * frozen
+ */
+ sector_t sect = r1_bio->sector;
+ int sectors = r1_bio->sectors;
+ freeze_array(conf);
+ if (mddev->ro == 0) while(sectors) {
+ int s = sectors;
+ int d = r1_bio->read_disk;
+ int success = 0;
+
+ if (s > (PAGE_SIZE>>9))
+ s = PAGE_SIZE >> 9;
+
+ do {
+ rdev = conf->mirrors[d].rdev;
+ if (rdev &&
+ test_bit(In_sync, &rdev->flags) &&
+ sync_page_io(rdev->bdev,
+ sect + rdev->data_offset,
+ s<<9,
+ conf->tmppage, READ))
+ success = 1;
+ else {
+ d++;
+ if (d == conf->raid_disks)
+ d = 0;
+ }
+ } while (!success && d != r1_bio->read_disk);
+
+ if (success) {
+ /* write it back and re-read */
+ int start = d;
+ while (d != r1_bio->read_disk) {
+ if (d==0)
+ d = conf->raid_disks;
+ d--;
+ rdev = conf->mirrors[d].rdev;
+ atomic_add(s, &rdev->corrected_errors);
+ if (rdev &&
+ test_bit(In_sync, &rdev->flags)) {
+ if (sync_page_io(rdev->bdev,
+ sect + rdev->data_offset,
+ s<<9, conf->tmppage, WRITE) == 0)
+ /* Well, this device is dead */
+ md_error(mddev, rdev);
+ }
+ }
+ d = start;
+ while (d != r1_bio->read_disk) {
+ if (d==0)
+ d = conf->raid_disks;
+ d--;
+ rdev = conf->mirrors[d].rdev;
+ if (rdev &&
+ test_bit(In_sync, &rdev->flags)) {
+ if (sync_page_io(rdev->bdev,
+ sect + rdev->data_offset,
+ s<<9, conf->tmppage, READ) == 0)
+ /* Well, this device is dead */
+ md_error(mddev, rdev);
+ }
+ }
+ } else {
+ /* Cannot read from anywhere -- bye bye array */
+ md_error(mddev, conf->mirrors[r1_bio->read_disk].rdev);
+ break;
+ }
+ sectors -= s;
+ sect += s;
+ }
+
+ unfreeze_array(conf);
+
bio = r1_bio->bios[r1_bio->read_disk];
if ((disk=read_balance(conf, r1_bio)) == -1) {
printk(KERN_ALERT "raid1: %s: unrecoverable I/O"
@@ -1214,7 +1508,8 @@ static void raid1d(mddev_t *mddev)
(unsigned long long)r1_bio->sector);
raid_end_bio_io(r1_bio);
} else {
- r1_bio->bios[r1_bio->read_disk] = NULL;
+ r1_bio->bios[r1_bio->read_disk] =
+ mddev->ro ? IO_BLOCKED : NULL;
r1_bio->read_disk = disk;
bio_put(bio);
bio = bio_clone(r1_bio->master_bio, GFP_NOIO);
@@ -1269,14 +1564,13 @@ static int init_resync(conf_t *conf)
static sector_t sync_request(mddev_t *mddev, sector_t sector_nr, int *skipped, int go_faster)
{
conf_t *conf = mddev_to_conf(mddev);
- mirror_info_t *mirror;
r1bio_t *r1_bio;
struct bio *bio;
sector_t max_sector, nr_sectors;
- int disk;
+ int disk = -1;
int i;
- int wonly;
- int write_targets = 0;
+ int wonly = -1;
+ int write_targets = 0, read_targets = 0;
int sync_blocks;
int still_degraded = 0;
@@ -1317,55 +1611,35 @@ static sector_t sync_request(mddev_t *mddev, sector_t sector_nr, int *skipped, i
return sync_blocks;
}
/*
- * If there is non-resync activity waiting for us then
- * put in a delay to throttle resync.
+ * If there is non-resync activity waiting for a turn,
+ * and resync is going fast enough,
+ * then let it though before starting on this new sync request.
*/
- if (!go_faster && waitqueue_active(&conf->wait_resume))
+ if (!go_faster && conf->nr_waiting)
msleep_interruptible(1000);
- device_barrier(conf, sector_nr + RESYNC_SECTORS);
-
- /*
- * If reconstructing, and >1 working disc,
- * could dedicate one to rebuild and others to
- * service read requests ..
- */
- disk = conf->last_used;
- /* make sure disk is operational */
- wonly = disk;
- while (conf->mirrors[disk].rdev == NULL ||
- !test_bit(In_sync, &conf->mirrors[disk].rdev->flags) ||
- test_bit(WriteMostly, &conf->mirrors[disk].rdev->flags)
- ) {
- if (conf->mirrors[disk].rdev &&
- test_bit(In_sync, &conf->mirrors[disk].rdev->flags))
- wonly = disk;
- if (disk <= 0)
- disk = conf->raid_disks;
- disk--;
- if (disk == conf->last_used) {
- disk = wonly;
- break;
- }
- }
- conf->last_used = disk;
- atomic_inc(&conf->mirrors[disk].rdev->nr_pending);
+ raise_barrier(conf);
- mirror = conf->mirrors + disk;
+ conf->next_resync = sector_nr;
r1_bio = mempool_alloc(conf->r1buf_pool, GFP_NOIO);
-
- spin_lock_irq(&conf->resync_lock);
- conf->nr_pending++;
- spin_unlock_irq(&conf->resync_lock);
+ rcu_read_lock();
+ /*
+ * If we get a correctably read error during resync or recovery,
+ * we might want to read from a different device. So we
+ * flag all drives that could conceivably be read from for READ,
+ * and any others (which will be non-In_sync devices) for WRITE.
+ * If a read fails, we try reading from something else for which READ
+ * is OK.
+ */
r1_bio->mddev = mddev;
r1_bio->sector = sector_nr;
r1_bio->state = 0;
set_bit(R1BIO_IsSync, &r1_bio->state);
- r1_bio->read_disk = disk;
for (i=0; i < conf->raid_disks; i++) {
+ mdk_rdev_t *rdev;
bio = r1_bio->bios[i];
/* take from bio_init */
@@ -1380,35 +1654,49 @@ static sector_t sync_request(mddev_t *mddev, sector_t sector_nr, int *skipped, i
bio->bi_end_io = NULL;
bio->bi_private = NULL;
- if (i == disk) {
- bio->bi_rw = READ;
- bio->bi_end_io = end_sync_read;
- } else if (conf->mirrors[i].rdev == NULL ||
- test_bit(Faulty, &conf->mirrors[i].rdev->flags)) {
+ rdev = rcu_dereference(conf->mirrors[i].rdev);
+ if (rdev == NULL ||
+ test_bit(Faulty, &rdev->flags)) {
still_degraded = 1;
continue;
- } else if (!test_bit(In_sync, &conf->mirrors[i].rdev->flags) ||
- sector_nr + RESYNC_SECTORS > mddev->recovery_cp ||
- test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) {
+ } else if (!test_bit(In_sync, &rdev->flags)) {
bio->bi_rw = WRITE;
bio->bi_end_io = end_sync_write;
write_targets ++;
- } else
- /* no need to read or write here */
- continue;
- bio->bi_sector = sector_nr + conf->mirrors[i].rdev->data_offset;
- bio->bi_bdev = conf->mirrors[i].rdev->bdev;
+ } else {
+ /* may need to read from here */
+ bio->bi_rw = READ;
+ bio->bi_end_io = end_sync_read;
+ if (test_bit(WriteMostly, &rdev->flags)) {
+ if (wonly < 0)
+ wonly = i;
+ } else {
+ if (disk < 0)
+ disk = i;
+ }
+ read_targets++;
+ }
+ atomic_inc(&rdev->nr_pending);
+ bio->bi_sector = sector_nr + rdev->data_offset;
+ bio->bi_bdev = rdev->bdev;
bio->bi_private = r1_bio;
}
+ rcu_read_unlock();
+ if (disk < 0)
+ disk = wonly;
+ r1_bio->read_disk = disk;
+
+ if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) && read_targets > 0)
+ /* extra read targets are also write targets */
+ write_targets += read_targets-1;
- if (write_targets == 0) {
+ if (write_targets == 0 || read_targets == 0) {
/* There is nowhere to write, so all non-sync
* drives must be failed - so we are finished
*/
sector_t rv = max_sector - sector_nr;
*skipped = 1;
put_buf(r1_bio);
- rdev_dec_pending(conf->mirrors[disk].rdev, mddev);
return rv;
}
@@ -1436,10 +1724,10 @@ static sector_t sync_request(mddev_t *mddev, sector_t sector_nr, int *skipped, i
for (i=0 ; i < conf->raid_disks; i++) {
bio = r1_bio->bios[i];
if (bio->bi_end_io) {
- page = r1_bio->bios[0]->bi_io_vec[bio->bi_vcnt].bv_page;
+ page = bio->bi_io_vec[bio->bi_vcnt].bv_page;
if (bio_add_page(bio, page, len, 0) == 0) {
/* stop here */
- r1_bio->bios[0]->bi_io_vec[bio->bi_vcnt].bv_page = page;
+ bio->bi_io_vec[bio->bi_vcnt].bv_page = page;
while (i > 0) {
i--;
bio = r1_bio->bios[i];
@@ -1459,12 +1747,28 @@ static sector_t sync_request(mddev_t *mddev, sector_t sector_nr, int *skipped, i
sync_blocks -= (len>>9);
} while (r1_bio->bios[disk]->bi_vcnt < RESYNC_PAGES);
bio_full:
- bio = r1_bio->bios[disk];
r1_bio->sectors = nr_sectors;
- md_sync_acct(mirror->rdev->bdev, nr_sectors);
+ /* For a user-requested sync, we read all readable devices and do a
+ * compare
+ */
+ if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) {
+ atomic_set(&r1_bio->remaining, read_targets);
+ for (i=0; i<conf->raid_disks; i++) {
+ bio = r1_bio->bios[i];
+ if (bio->bi_end_io == end_sync_read) {
+ md_sync_acct(conf->mirrors[i].rdev->bdev, nr_sectors);
+ generic_make_request(bio);
+ }
+ }
+ } else {
+ atomic_set(&r1_bio->remaining, 1);
+ bio = r1_bio->bios[r1_bio->read_disk];
+ md_sync_acct(conf->mirrors[r1_bio->read_disk].rdev->bdev,
+ nr_sectors);
+ generic_make_request(bio);
- generic_make_request(bio);
+ }
return nr_sectors;
}
@@ -1487,18 +1791,19 @@ static int run(mddev_t *mddev)
* bookkeeping area. [whatever we allocate in run(),
* should be freed in stop()]
*/
- conf = kmalloc(sizeof(conf_t), GFP_KERNEL);
+ conf = kzalloc(sizeof(conf_t), GFP_KERNEL);
mddev->private = conf;
if (!conf)
goto out_no_mem;
- memset(conf, 0, sizeof(*conf));
- conf->mirrors = kmalloc(sizeof(struct mirror_info)*mddev->raid_disks,
+ conf->mirrors = kzalloc(sizeof(struct mirror_info)*mddev->raid_disks,
GFP_KERNEL);
if (!conf->mirrors)
goto out_no_mem;
- memset(conf->mirrors, 0, sizeof(struct mirror_info)*mddev->raid_disks);
+ conf->tmppage = alloc_page(GFP_KERNEL);
+ if (!conf->tmppage)
+ goto out_no_mem;
conf->poolinfo = kmalloc(sizeof(*conf->poolinfo), GFP_KERNEL);
if (!conf->poolinfo)
@@ -1542,8 +1847,7 @@ static int run(mddev_t *mddev)
mddev->recovery_cp = MaxSector;
spin_lock_init(&conf->resync_lock);
- init_waitqueue_head(&conf->wait_idle);
- init_waitqueue_head(&conf->wait_resume);
+ init_waitqueue_head(&conf->wait_barrier);
bio_list_init(&conf->pending_bio_list);
bio_list_init(&conf->flushing_bio_list);
@@ -1583,7 +1887,6 @@ static int run(mddev_t *mddev)
mdname(mddev));
goto out_free_conf;
}
- if (mddev->bitmap) mddev->thread->timeout = mddev->bitmap->daemon_sleep * HZ;
printk(KERN_INFO
"raid1: raid set %s active with %d out of %d mirrors\n",
@@ -1608,6 +1911,7 @@ out_free_conf:
if (conf->r1bio_pool)
mempool_destroy(conf->r1bio_pool);
kfree(conf->mirrors);
+ safe_put_page(conf->tmppage);
kfree(conf->poolinfo);
kfree(conf);
mddev->private = NULL;
@@ -1706,19 +2010,14 @@ static int raid1_reshape(mddev_t *mddev, int raid_disks)
kfree(newpoolinfo);
return -ENOMEM;
}
- newmirrors = kmalloc(sizeof(struct mirror_info) * raid_disks, GFP_KERNEL);
+ newmirrors = kzalloc(sizeof(struct mirror_info) * raid_disks, GFP_KERNEL);
if (!newmirrors) {
kfree(newpoolinfo);
mempool_destroy(newpool);
return -ENOMEM;
}
- memset(newmirrors, 0, sizeof(struct mirror_info)*raid_disks);
- spin_lock_irq(&conf->resync_lock);
- conf->barrier++;
- wait_event_lock_irq(conf->wait_idle, !conf->nr_pending,
- conf->resync_lock, raid1_unplug(mddev->queue));
- spin_unlock_irq(&conf->resync_lock);
+ raise_barrier(conf);
/* ok, everything is stopped */
oldpool = conf->r1bio_pool;
@@ -1738,12 +2037,7 @@ static int raid1_reshape(mddev_t *mddev, int raid_disks)
conf->raid_disks = mddev->raid_disks = raid_disks;
conf->last_used = 0; /* just make sure it is in-range */
- spin_lock_irq(&conf->resync_lock);
- conf->barrier--;
- spin_unlock_irq(&conf->resync_lock);
- wake_up(&conf->wait_resume);
- wake_up(&conf->wait_idle);
-
+ lower_barrier(conf);
set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
md_wakeup_thread(mddev->thread);
@@ -1758,33 +2052,19 @@ static void raid1_quiesce(mddev_t *mddev, int state)
switch(state) {
case 1:
- spin_lock_irq(&conf->resync_lock);
- conf->barrier++;
- wait_event_lock_irq(conf->wait_idle, !conf->nr_pending,
- conf->resync_lock, raid1_unplug(mddev->queue));
- spin_unlock_irq(&conf->resync_lock);
+ raise_barrier(conf);
break;
case 0:
- spin_lock_irq(&conf->resync_lock);
- conf->barrier--;
- spin_unlock_irq(&conf->resync_lock);
- wake_up(&conf->wait_resume);
- wake_up(&conf->wait_idle);
+ lower_barrier(conf);
break;
}
- if (mddev->thread) {
- if (mddev->bitmap)
- mddev->thread->timeout = mddev->bitmap->daemon_sleep * HZ;
- else
- mddev->thread->timeout = MAX_SCHEDULE_TIMEOUT;
- md_wakeup_thread(mddev->thread);
- }
}
-static mdk_personality_t raid1_personality =
+static struct mdk_personality raid1_personality =
{
.name = "raid1",
+ .level = 1,
.owner = THIS_MODULE,
.make_request = make_request,
.run = run,
@@ -1802,15 +2082,17 @@ static mdk_personality_t raid1_personality =
static int __init raid_init(void)
{
- return register_md_personality(RAID1, &raid1_personality);
+ return register_md_personality(&raid1_personality);
}
static void raid_exit(void)
{
- unregister_md_personality(RAID1);
+ unregister_md_personality(&raid1_personality);
}
module_init(raid_init);
module_exit(raid_exit);
MODULE_LICENSE("GPL");
MODULE_ALIAS("md-personality-3"); /* RAID1 */
+MODULE_ALIAS("md-raid1");
+MODULE_ALIAS("md-level-1");
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