[PATCH] md: add write-intent-bitmap support to raid5

[linux-2.6] / drivers / md / md.c

diff --git a/drivers/md/md.c b/drivers/md/md.c
index 866c704e008a1c22a89348292803486bc11229c3..dbf540a7fccca797495541f861a0d3255eb6f8a7 100644 (file)
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -393,7 +393,7 @@ int sync_page_io(struct block_device *bdev, sector_t sector, int size,
        return ret;
 }
 
-static int read_disk_sb(mdk_rdev_t * rdev)
+static int read_disk_sb(mdk_rdev_t * rdev, int size)
 {
        char b[BDEVNAME_SIZE];
        if (!rdev->sb_page) {
@@ -404,7 +404,7 @@ static int read_disk_sb(mdk_rdev_t * rdev)
                return 0;
 
 
-       if (!sync_page_io(rdev->bdev, rdev->sb_offset<<1, MD_SB_BYTES, rdev->sb_page, READ))
+       if (!sync_page_io(rdev->bdev, rdev->sb_offset<<1, size, rdev->sb_page, READ))
                goto fail;
        rdev->sb_loaded = 1;
        return 0;
@@ -531,7 +531,7 @@ static int super_90_load(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version
        sb_offset = calc_dev_sboffset(rdev->bdev);
        rdev->sb_offset = sb_offset;
 
-       ret = read_disk_sb(rdev);
+       ret = read_disk_sb(rdev, MD_SB_BYTES);
        if (ret) return ret;
 
        ret = -EINVAL;
@@ -564,6 +564,7 @@ static int super_90_load(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version
 
        rdev->preferred_minor = sb->md_minor;
        rdev->data_offset = 0;
+       rdev->sb_size = MD_SB_BYTES;
 
        if (sb->level == LEVEL_MULTIPATH)
                rdev->desc_nr = -1;
@@ -644,7 +645,7 @@ static int super_90_validate(mddev_t *mddev, mdk_rdev_t *rdev)
 
                if (sb->state & (1<<MD_SB_BITMAP_PRESENT) &&
                    mddev->bitmap_file == NULL) {
-                       if (mddev->level != 1) {
+                       if (mddev->level != 1 && mddev->level != 5) {
                                /* FIXME use a better test */
                                printk(KERN_WARNING "md: bitmaps only support for raid1\n");
                                return -EINVAL;
@@ -837,6 +838,7 @@ static int super_1_load(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version)
        int ret;
        sector_t sb_offset;
        char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
+       int bmask;
 
        /*
         * Calculate the position of the superblock.
@@ -865,7 +867,10 @@ static int super_1_load(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version)
        }
        rdev->sb_offset = sb_offset;
 
-       ret = read_disk_sb(rdev);
+       /* superblock is rarely larger than 1K, but it can be larger,
+        * and it is safe to read 4k, so we do that
+        */
+       ret = read_disk_sb(rdev, 4096);
        if (ret) return ret;
 
 
@@ -875,7 +880,7 @@ static int super_1_load(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version)
            sb->major_version != cpu_to_le32(1) ||
            le32_to_cpu(sb->max_dev) > (4096-256)/2 ||
            le64_to_cpu(sb->super_offset) != (rdev->sb_offset<<1) ||
-           sb->feature_map != 0)
+           (le32_to_cpu(sb->feature_map) & ~MD_FEATURE_ALL) != 0)
                return -EINVAL;
 
        if (calc_sb_1_csum(sb) != sb->sb_csum) {
@@ -891,6 +896,11 @@ static int super_1_load(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version)
        rdev->preferred_minor = 0xffff;
        rdev->data_offset = le64_to_cpu(sb->data_offset);
 
+       rdev->sb_size = le32_to_cpu(sb->max_dev) * 2 + 256;
+       bmask = block_size(rdev->bdev)-1;
+       if (rdev->sb_size & bmask)
+               rdev-> sb_size = (rdev->sb_size | bmask)+1;
+
        if (refdev == 0)
                return 1;
        else {
@@ -954,7 +964,7 @@ static int super_1_validate(mddev_t *mddev, mdk_rdev_t *rdev)
 
                mddev->max_disks =  (4096-256)/2;
 
-               if ((le32_to_cpu(sb->feature_map) & 1) &&
+               if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_BITMAP_OFFSET) &&
                    mddev->bitmap_file == NULL ) {
                        if (mddev->level != 1) {
                                printk(KERN_WARNING "md: bitmaps only supported for raid1\n");
@@ -1029,7 +1039,7 @@ static void super_1_sync(mddev_t *mddev, mdk_rdev_t *rdev)
 
        if (mddev->bitmap && mddev->bitmap_file == NULL) {
                sb->bitmap_offset = cpu_to_le32((__u32)mddev->bitmap_offset);
-               sb->feature_map = cpu_to_le32(1);
+               sb->feature_map = cpu_to_le32(MD_FEATURE_BITMAP_OFFSET);
        }
 
        max_dev = 0;
@@ -1375,7 +1385,7 @@ repeat:
                dprintk("%s ", bdevname(rdev->bdev,b));
                if (!rdev->faulty) {
                        md_super_write(mddev,rdev,
-                                      rdev->sb_offset<<1, MD_SB_BYTES,
+                                      rdev->sb_offset<<1, rdev->sb_size,
                                       rdev->sb_page);
                        dprintk(KERN_INFO "(write) %s's sb offset: %llu\n",
                                bdevname(rdev->bdev,b),
@@ -3507,7 +3517,6 @@ void md_done_sync(mddev_t *mddev, int blocks, int ok)
  */
 void md_write_start(mddev_t *mddev, struct bio *bi)
 {
-       DEFINE_WAIT(w);
        if (bio_data_dir(bi) != WRITE)
                return;