md: load/store badblock list from v1.x metadata

Space must have been allocated when array was created.
A feature flag is set when the badblock list is non-empty, to
ensure old kernels don't load and trust the whole device.

We only update the on-disk badblocklist when it has changed.
If the badblocklist (or other metadata) is stored on a bad block, we
don't cope very well.

If metadata has no room for bad block, flag bad-blocks as disabled,
and do the same for 0.90 metadata.

Signed-off-by: NeilBrown <neilb@suse.de>

diff --git a/drivers/md/md.c b/drivers/md/md.c
index 7f5ffc5..e2ec8bd 100644 (file)
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -757,6 +757,10 @@ static void free_disk_sb(mdk_rdev_t * rdev)
                rdev->sb_start = 0;
                rdev->sectors = 0;
        }
+       if (rdev->bb_page) {
+               put_page(rdev->bb_page);
+               rdev->bb_page = NULL;
+       }
 }
 
 
@@ -1395,6 +1399,8 @@ static __le32 calc_sb_1_csum(struct mdp_superblock_1 * sb)
        return cpu_to_le32(csum);
 }
 
+static int md_set_badblocks(struct badblocks *bb, sector_t s, int sectors,
+                           int acknowledged);
 static int super_1_load(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version)
 {
        struct mdp_superblock_1 *sb;
@@ -1473,6 +1479,47 @@ static int super_1_load(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version)
        else
                rdev->desc_nr = le32_to_cpu(sb->dev_number);
 
+       if (!rdev->bb_page) {
+               rdev->bb_page = alloc_page(GFP_KERNEL);
+               if (!rdev->bb_page)
+                       return -ENOMEM;
+       }
+       if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_BAD_BLOCKS) &&
+           rdev->badblocks.count == 0) {
+               /* need to load the bad block list.
+                * Currently we limit it to one page.
+                */
+               s32 offset;
+               sector_t bb_sector;
+               u64 *bbp;
+               int i;
+               int sectors = le16_to_cpu(sb->bblog_size);
+               if (sectors > (PAGE_SIZE / 512))
+                       return -EINVAL;
+               offset = le32_to_cpu(sb->bblog_offset);
+               if (offset == 0)
+                       return -EINVAL;
+               bb_sector = (long long)offset;
+               if (!sync_page_io(rdev, bb_sector, sectors << 9,
+                                 rdev->bb_page, READ, true))
+                       return -EIO;
+               bbp = (u64 *)page_address(rdev->bb_page);
+               rdev->badblocks.shift = sb->bblog_shift;
+               for (i = 0 ; i < (sectors << (9-3)) ; i++, bbp++) {
+                       u64 bb = le64_to_cpu(*bbp);
+                       int count = bb & (0x3ff);
+                       u64 sector = bb >> 10;
+                       sector <<= sb->bblog_shift;
+                       count <<= sb->bblog_shift;
+                       if (bb + 1 == 0)
+                               break;
+                       if (md_set_badblocks(&rdev->badblocks,
+                                            sector, count, 1) == 0)
+                               return -EINVAL;
+               }
+       } else if (sb->bblog_offset == 0)
+               rdev->badblocks.shift = -1;
+
        if (!refdev) {
                ret = 1;
        } else {
@@ -1624,7 +1671,6 @@ static void super_1_sync(mddev_t *mddev, mdk_rdev_t *rdev)
        sb->pad0 = 0;
        sb->recovery_offset = cpu_to_le64(0);
        memset(sb->pad1, 0, sizeof(sb->pad1));
-       memset(sb->pad2, 0, sizeof(sb->pad2));
        memset(sb->pad3, 0, sizeof(sb->pad3));
 
        sb->utime = cpu_to_le64((__u64)mddev->utime);
@@ -1664,6 +1710,40 @@ static void super_1_sync(mddev_t *mddev, mdk_rdev_t *rdev)
                sb->new_chunk = cpu_to_le32(mddev->new_chunk_sectors);
        }
 
+       if (rdev->badblocks.count == 0)
+               /* Nothing to do for bad blocks*/ ;
+       else if (sb->bblog_offset == 0)
+               /* Cannot record bad blocks on this device */
+               md_error(mddev, rdev);
+       else {
+               struct badblocks *bb = &rdev->badblocks;
+               u64 *bbp = (u64 *)page_address(rdev->bb_page);
+               u64 *p = bb->page;
+               sb->feature_map |= cpu_to_le32(MD_FEATURE_BAD_BLOCKS);
+               if (bb->changed) {
+                       unsigned seq;
+
+retry:
+                       seq = read_seqbegin(&bb->lock);
+
+                       memset(bbp, 0xff, PAGE_SIZE);
+
+                       for (i = 0 ; i < bb->count ; i++) {
+                               u64 internal_bb = *p++;
+                               u64 store_bb = ((BB_OFFSET(internal_bb) << 10)
+                                               | BB_LEN(internal_bb));
+                               *bbp++ = cpu_to_le64(store_bb);
+                       }
+                       if (read_seqretry(&bb->lock, seq))
+                               goto retry;
+
+                       bb->sector = (rdev->sb_start +
+                                     (int)le32_to_cpu(sb->bblog_offset));
+                       bb->size = le16_to_cpu(sb->bblog_size);
+                       bb->changed = 0;
+               }
+       }
+
        max_dev = 0;
        list_for_each_entry(rdev2, &mddev->disks, same_set)
                if (rdev2->desc_nr+1 > max_dev)
@@ -2196,6 +2276,7 @@ static void md_update_sb(mddev_t * mddev, int force_change)
        mdk_rdev_t *rdev;
        int sync_req;
        int nospares = 0;
+       int any_badblocks_changed = 0;
 
 repeat:
        /* First make sure individual recovery_offsets are correct */
@@ -2267,6 +2348,11 @@ repeat:
                MD_BUG();
                mddev->events --;
        }
+
+       list_for_each_entry(rdev, &mddev->disks, same_set)
+               if (rdev->badblocks.changed)
+                       any_badblocks_changed++;
+
        sync_sbs(mddev, nospares);
        spin_unlock_irq(&mddev->write_lock);
 
@@ -2292,6 +2378,13 @@ repeat:
                                bdevname(rdev->bdev,b),
                                (unsigned long long)rdev->sb_start);
                        rdev->sb_events = mddev->events;
+                       if (rdev->badblocks.size) {
+                               md_super_write(mddev, rdev,
+                                              rdev->badblocks.sector,
+                                              rdev->badblocks.size << 9,
+                                              rdev->bb_page);
+                               rdev->badblocks.size = 0;
+                       }
 
                } else
                        dprintk(")\n");
@@ -2315,6 +2408,9 @@ repeat:
        if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
                sysfs_notify(&mddev->kobj, NULL, "sync_completed");
 
+       if (any_badblocks_changed)
+               list_for_each_entry(rdev, &mddev->disks, same_set)
+                       md_ack_all_badblocks(&rdev->badblocks);
 }
 
 /* words written to sysfs files may, or may not, be \n terminated.
@@ -2822,6 +2918,8 @@ int md_rdev_init(mdk_rdev_t *rdev)
        rdev->sb_events = 0;
        rdev->last_read_error.tv_sec  = 0;
        rdev->last_read_error.tv_nsec = 0;
+       rdev->sb_loaded = 0;
+       rdev->bb_page = NULL;
        atomic_set(&rdev->nr_pending, 0);
        atomic_set(&rdev->read_errors, 0);
        atomic_set(&rdev->corrected_errors, 0);
@@ -2910,11 +3008,9 @@ static mdk_rdev_t *md_import_device(dev_t newdev, int super_format, int super_mi
        return rdev;
 
 abort_free:
-       if (rdev->sb_page) {
-               if (rdev->bdev)
-                       unlock_rdev(rdev);
-               free_disk_sb(rdev);
-       }
+       if (rdev->bdev)
+               unlock_rdev(rdev);
+       free_disk_sb(rdev);
        kfree(rdev->badblocks.page);
        kfree(rdev);
        return ERR_PTR(err);

diff --git a/drivers/md/md.h b/drivers/md/md.h
index 85af843..aea9e9f 100644 (file)
--- a/drivers/md/md.h
+++ b/drivers/md/md.h
@@ -55,7 +55,7 @@ struct mdk_rdev_s
        struct block_device *meta_bdev;
        struct block_device *bdev;      /* block device handle */
 
-       struct page     *sb_page;
+       struct page     *sb_page, *bb_page;
        int             sb_loaded;
        __u64           sb_events;
        sector_t        data_offset;    /* start of data in array */
@@ -127,6 +127,9 @@ struct mdk_rdev_s
                u64     *page;          /* badblock list */
                int     changed;
                seqlock_t lock;
+
+               sector_t sector;
+               sector_t size;          /* in sectors */
        } badblocks;
 };
 

diff --git a/include/linux/raid/md_p.h b/include/linux/raid/md_p.h
index 75cbf4f..9e65d9e 100644 (file)
--- a/include/linux/raid/md_p.h
+++ b/include/linux/raid/md_p.h
@@ -245,10 +245,16 @@ struct mdp_superblock_1 {
        __u8    device_uuid[16]; /* user-space setable, ignored by kernel */
        __u8    devflags;       /* per-device flags.  Only one defined...*/
 #define        WriteMostly1    1       /* mask for writemostly flag in above */
-       __u8    pad2[64-57];    /* set to 0 when writing */
+       /* Bad block log.  If there are any bad blocks the feature flag is set.
+        * If offset and size are non-zero, that space is reserved and available
+        */
+       __u8    bblog_shift;    /* shift from sectors to block size */
+       __le16  bblog_size;     /* number of sectors reserved for list */
+       __le32  bblog_offset;   /* sector offset from superblock to bblog,
+                                * signed - not unsigned */
 
        /* array state information - 64 bytes */
-       __le64  utime;          /* 40 bits second, 24 btes microseconds */
+       __le64  utime;          /* 40 bits second, 24 bits microseconds */
        __le64  events;         /* incremented when superblock updated */
        __le64  resync_offset;  /* data before this offset (from data_offset) known to be in sync */
        __le32  sb_csum;        /* checksum up to devs[max_dev] */
@@ -270,8 +276,8 @@ struct mdp_superblock_1 {
                                           * must be honoured
                                           */
 #define        MD_FEATURE_RESHAPE_ACTIVE       4
+#define        MD_FEATURE_BAD_BLOCKS           8 /* badblock list is not empty */
 
-#define        MD_FEATURE_ALL                  (1|2|4)
+#define        MD_FEATURE_ALL                  (1|2|4|8)
 
 #endif 
-