Merge tag 'md-3.6-fixes' of git://neil.brown.name/md

Pull md fixes from NeilBrown:
 "2 fixes for md, tagged for -stable"

* tag 'md-3.6-fixes' of git://neil.brown.name/md:
  md/raid10: fix problem with on-stack allocation of r10bio structure.
  md: Don't truncate size at 4TB for RAID0 and Linear

diff --git a/drivers/md/md.c b/drivers/md/md.c
index fcd0987..3f6203a 100644 (file)
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -1108,8 +1108,11 @@ static int super_90_load(struct md_rdev *rdev, struct md_rdev *refdev, int minor
                        ret = 0;
        }
        rdev->sectors = rdev->sb_start;
-       /* Limit to 4TB as metadata cannot record more than that */
-       if (rdev->sectors >= (2ULL << 32))
+       /* Limit to 4TB as metadata cannot record more than that.
+        * (not needed for Linear and RAID0 as metadata doesn't
+        * record this size)
+        */
+       if (rdev->sectors >= (2ULL << 32) && sb->level >= 1)
                rdev->sectors = (2ULL << 32) - 2;
 
        if (rdev->sectors < ((sector_t)sb->size) * 2 && sb->level >= 1)
@@ -1400,7 +1403,7 @@ super_90_rdev_size_change(struct md_rdev *rdev, sector_t num_sectors)
        /* Limit to 4TB as metadata cannot record more than that.
         * 4TB == 2^32 KB, or 2*2^32 sectors.
         */
-       if (num_sectors >= (2ULL << 32))
+       if (num_sectors >= (2ULL << 32) && rdev->mddev->level >= 1)
                num_sectors = (2ULL << 32) - 2;
        md_super_write(rdev->mddev, rdev, rdev->sb_start, rdev->sb_size,
                       rdev->sb_page);

diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index de5ed6f..1c2eb38 100644 (file)
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -659,7 +659,11 @@ static int raid10_mergeable_bvec(struct request_queue *q,
                max = biovec->bv_len;
 
        if (mddev->merge_check_needed) {
-               struct r10bio r10_bio;
+               struct {
+                       struct r10bio r10_bio;
+                       struct r10dev devs[conf->copies];
+               } on_stack;
+               struct r10bio *r10_bio = &on_stack.r10_bio;
                int s;
                if (conf->reshape_progress != MaxSector) {
                        /* Cannot give any guidance during reshape */
@@ -667,18 +671,18 @@ static int raid10_mergeable_bvec(struct request_queue *q,
                                return biovec->bv_len;
                        return 0;
                }
-               r10_bio.sector = sector;
-               raid10_find_phys(conf, &r10_bio);
+               r10_bio->sector = sector;
+               raid10_find_phys(conf, r10_bio);
                rcu_read_lock();
                for (s = 0; s < conf->copies; s++) {
-                       int disk = r10_bio.devs[s].devnum;
+                       int disk = r10_bio->devs[s].devnum;
                        struct md_rdev *rdev = rcu_dereference(
                                conf->mirrors[disk].rdev);
                        if (rdev && !test_bit(Faulty, &rdev->flags)) {
                                struct request_queue *q =
                                        bdev_get_queue(rdev->bdev);
                                if (q->merge_bvec_fn) {
-                                       bvm->bi_sector = r10_bio.devs[s].addr
+                                       bvm->bi_sector = r10_bio->devs[s].addr
                                                + rdev->data_offset;
                                        bvm->bi_bdev = rdev->bdev;
                                        max = min(max, q->merge_bvec_fn(
@@ -690,7 +694,7 @@ static int raid10_mergeable_bvec(struct request_queue *q,
                                struct request_queue *q =
                                        bdev_get_queue(rdev->bdev);
                                if (q->merge_bvec_fn) {
-                                       bvm->bi_sector = r10_bio.devs[s].addr
+                                       bvm->bi_sector = r10_bio->devs[s].addr
                                                + rdev->data_offset;
                                        bvm->bi_bdev = rdev->bdev;
                                        max = min(max, q->merge_bvec_fn(
@@ -4414,14 +4418,18 @@ static int handle_reshape_read_error(struct mddev *mddev,
 {
        /* Use sync reads to get the blocks from somewhere else */
        int sectors = r10_bio->sectors;
-       struct r10bio r10b;
        struct r10conf *conf = mddev->private;
+       struct {
+               struct r10bio r10_bio;
+               struct r10dev devs[conf->copies];
+       } on_stack;
+       struct r10bio *r10b = &on_stack.r10_bio;
        int slot = 0;
        int idx = 0;
        struct bio_vec *bvec = r10_bio->master_bio->bi_io_vec;
 
-       r10b.sector = r10_bio->sector;
-       __raid10_find_phys(&conf->prev, &r10b);
+       r10b->sector = r10_bio->sector;
+       __raid10_find_phys(&conf->prev, r10b);
 
        while (sectors) {
                int s = sectors;
@@ -4432,7 +4440,7 @@ static int handle_reshape_read_error(struct mddev *mddev,
                        s = PAGE_SIZE >> 9;
 
                while (!success) {
-                       int d = r10b.devs[slot].devnum;
+                       int d = r10b->devs[slot].devnum;
                        struct md_rdev *rdev = conf->mirrors[d].rdev;
                        sector_t addr;
                        if (rdev == NULL ||
@@ -4440,7 +4448,7 @@ static int handle_reshape_read_error(struct mddev *mddev,
                            !test_bit(In_sync, &rdev->flags))
                                goto failed;
 
-                       addr = r10b.devs[slot].addr + idx * PAGE_SIZE;
+                       addr = r10b->devs[slot].addr + idx * PAGE_SIZE;
                        success = sync_page_io(rdev,
                                               addr,
                                               s << 9,

diff --git a/drivers/md/raid10.h b/drivers/md/raid10.h
index 007c2c6..1054cf6 100644 (file)
--- a/drivers/md/raid10.h
+++ b/drivers/md/raid10.h
@@ -110,7 +110,7 @@ struct r10bio {
         * We choose the number when they are allocated.
         * We sometimes need an extra bio to write to the replacement.
         */
-       struct {
+       struct r10dev {
                struct bio      *bio;
                union {
                        struct bio      *repl_bio; /* used for resync and