5 files changed, 76 insertions, 142 deletions

diff --git a/fs/btrfs/file-item.c b/fs/btrfs/file-item.c
index b193bf324a41..a7bfc9541803 100644
--- a/fs/btrfs/file-item.c
+++ b/fs/btrfs/file-item.c
@@ -34,8 +34,7 @@
 
 #define MAX_ORDERED_SUM_BYTES(r) ((PAGE_SIZE - \
                                    sizeof(struct btrfs_ordered_sum)) / \
-                                   sizeof(struct btrfs_sector_sum) * \
-                                   (r)->sectorsize - (r)->sectorsize)
+                                   sizeof(u32) * (r)->sectorsize)
 
 int btrfs_insert_file_extent(struct btrfs_trans_handle *trans,
                              struct btrfs_root *root,
@@ -297,7 +296,6 @@ int btrfs_lookup_csums_range(struct btrfs_root *root, u64 start, u64 end,
         struct btrfs_path *path;
         struct extent_buffer *leaf;
         struct btrfs_ordered_sum *sums;
-        struct btrfs_sector_sum *sector_sum;
         struct btrfs_csum_item *item;
         LIST_HEAD(tmplist);
         unsigned long offset;
@@ -368,34 +366,28 @@ int btrfs_lookup_csums_range(struct btrfs_root *root, u64 start, u64 end,
                                       struct btrfs_csum_item);
                 while (start < csum_end) {
                         size = min_t(size_t, csum_end - start,
-                                        MAX_ORDERED_SUM_BYTES(root));
+                                     MAX_ORDERED_SUM_BYTES(root));
                         sums = kzalloc(btrfs_ordered_sum_size(root, size),
-                                        GFP_NOFS);
+                                       GFP_NOFS);
                         if (!sums) {
                                 ret = -ENOMEM;
                                 goto fail;
                         }
 
-                        sector_sum = sums->sums;
                         sums->bytenr = start;
-                        sums->len = size;
+                        sums->len = (int)size;
 
                         offset = (start - key.offset) >>
                                 root->fs_info->sb->s_blocksize_bits;
                         offset *= csum_size;
+                        size >>= root->fs_info->sb->s_blocksize_bits;
 
-                        while (size > 0) {
-                                read_extent_buffer(path->nodes[0],
-                                                &sector_sum->sum,
-                                                ((unsigned long)item) +
-                                                offset, csum_size);
-                                sector_sum->bytenr = start;
-
-                                size -= root->sectorsize;
-                                start += root->sectorsize;
-                                offset += csum_size;
-                                sector_sum++;
-                        }
+                        read_extent_buffer(path->nodes[0],
+                                           sums->sums,
+                                           ((unsigned long)item) + offset,
+                                           csum_size * size);
+
+                        start += root->sectorsize * size;
                         list_add_tail(&sums->list, &tmplist);
                 }
                 path->slots[0]++;
@@ -417,23 +409,20 @@ int btrfs_csum_one_bio(struct btrfs_root *root, struct inode *inode,
                        struct bio *bio, u64 file_start, int contig)
 {
         struct btrfs_ordered_sum *sums;
-        struct btrfs_sector_sum *sector_sum;
         struct btrfs_ordered_extent *ordered;
         char *data;
         struct bio_vec *bvec = bio->bi_io_vec;
         int bio_index = 0;
+        int index;
         unsigned long total_bytes = 0;
         unsigned long this_sum_bytes = 0;
         u64 offset;
-        u64 disk_bytenr;
 
         WARN_ON(bio->bi_vcnt <= 0);
         sums = kzalloc(btrfs_ordered_sum_size(root, bio->bi_size), GFP_NOFS);
         if (!sums)
                 return -ENOMEM;
 
-        sector_sum = sums->sums;
-        disk_bytenr = (u64)bio->bi_sector << 9;
         sums->len = bio->bi_size;
         INIT_LIST_HEAD(&sums->list);
 
@@ -444,7 +433,8 @@ int btrfs_csum_one_bio(struct btrfs_root *root, struct inode *inode,
 
         ordered = btrfs_lookup_ordered_extent(inode, offset);
         BUG_ON(!ordered); /* Logic error */
-        sums->bytenr = ordered->start;
+        sums->bytenr = (u64)bio->bi_sector << 9;
+        index = 0;
 
         while (bio_index < bio->bi_vcnt) {
                 if (!contig)
@@ -463,28 +453,27 @@ int btrfs_csum_one_bio(struct btrfs_root *root, struct inode *inode,
                         sums = kzalloc(btrfs_ordered_sum_size(root, bytes_left),
                                        GFP_NOFS);
                         BUG_ON(!sums); /* -ENOMEM */
-                        sector_sum = sums->sums;
                         sums->len = bytes_left;
                         ordered = btrfs_lookup_ordered_extent(inode, offset);
                         BUG_ON(!ordered); /* Logic error */
-                        sums->bytenr = ordered->start;
+                        sums->bytenr = ((u64)bio->bi_sector << 9) +
+                                       total_bytes;
+                        index = 0;
                 }
 
                 data = kmap_atomic(bvec->bv_page);
-                sector_sum->sum = ~(u32)0;
-                sector_sum->sum = btrfs_csum_data(data + bvec->bv_offset,
-                                                  sector_sum->sum,
-                                                  bvec->bv_len);
+                sums->sums[index] = ~(u32)0;
+                sums->sums[index] = btrfs_csum_data(data + bvec->bv_offset,
+                                                    sums->sums[index],
+                                                    bvec->bv_len);
                 kunmap_atomic(data);
-                btrfs_csum_final(sector_sum->sum,
-                                 (char *)&sector_sum->sum);
-                sector_sum->bytenr = disk_bytenr;
+                btrfs_csum_final(sums->sums[index],
+                                 (char *)(sums->sums + index));
 
-                sector_sum++;
                 bio_index++;
+                index++;
                 total_bytes += bvec->bv_len;
                 this_sum_bytes += bvec->bv_len;
-                disk_bytenr += bvec->bv_len;
                 offset += bvec->bv_len;
                 bvec++;
         }
@@ -672,62 +661,46 @@ out:
         return ret;
 }
 
-static u64 btrfs_sector_sum_left(struct btrfs_ordered_sum *sums,
-                                 struct btrfs_sector_sum *sector_sum,
-                                 u64 total_bytes, u64 sectorsize)
-{
-        u64 tmp = sectorsize;
-        u64 next_sector = sector_sum->bytenr;
-        struct btrfs_sector_sum *next = sector_sum + 1;
-
-        while ((tmp + total_bytes) < sums->len) {
-                if (next_sector + sectorsize != next->bytenr)
-                        break;
-                tmp += sectorsize;
-                next_sector = next->bytenr;
-                next++;
-        }
-        return tmp;
-}
-
 int btrfs_csum_file_blocks(struct btrfs_trans_handle *trans,
                            struct btrfs_root *root,
                            struct btrfs_ordered_sum *sums)
 {
-        u64 bytenr;
-        int ret;
         struct btrfs_key file_key;
         struct btrfs_key found_key;
-        u64 next_offset;
-        u64 total_bytes = 0;
-        int found_next;
         struct btrfs_path *path;
         struct btrfs_csum_item *item;
         struct btrfs_csum_item *item_end;
         struct extent_buffer *leaf = NULL;
+        u64 next_offset;
+        u64 total_bytes = 0;
         u64 csum_offset;
-        struct btrfs_sector_sum *sector_sum;
+        u64 bytenr;
         u32 nritems;
         u32 ins_size;
+        int index = 0;
+        int found_next;
+        int ret;
         u16 csum_size = btrfs_super_csum_size(root->fs_info->super_copy);
 
         path = btrfs_alloc_path();
         if (!path)
                 return -ENOMEM;
-
-        sector_sum = sums->sums;
 again:
         next_offset = (u64)-1;
         found_next = 0;
+        bytenr = sums->bytenr + total_bytes;
         file_key.objectid = BTRFS_EXTENT_CSUM_OBJECTID;
-        file_key.offset = sector_sum->bytenr;
-        bytenr = sector_sum->bytenr;
+        file_key.offset = bytenr;
         btrfs_set_key_type(&file_key, BTRFS_EXTENT_CSUM_KEY);
 
-        item = btrfs_lookup_csum(trans, root, path, sector_sum->bytenr, 1);
+        item = btrfs_lookup_csum(trans, root, path, bytenr, 1);
         if (!IS_ERR(item)) {
-                leaf = path->nodes[0];
                 ret = 0;
+                leaf = path->nodes[0];
+                item_end = btrfs_item_ptr(leaf, path->slots[0],
+                                          struct btrfs_csum_item);
+                item_end = (struct btrfs_csum_item *)((char *)item_end +
+                           btrfs_item_size_nr(leaf, path->slots[0]));
                 goto found;
         }
         ret = PTR_ERR(item);
@@ -807,8 +780,7 @@ again:
 
                 free_space = btrfs_leaf_free_space(root, leaf) -
                                          sizeof(struct btrfs_item) - csum_size;
-                tmp = btrfs_sector_sum_left(sums, sector_sum, total_bytes,
-                                            root->sectorsize);
+                tmp = sums->len - total_bytes;
                 tmp >>= root->fs_info->sb->s_blocksize_bits;
                 WARN_ON(tmp < 1);
 
@@ -822,6 +794,7 @@ again:
                 diff *= csum_size;
 
                 btrfs_extend_item(root, path, diff);
+                ret = 0;
                 goto csum;
         }
 
@@ -831,8 +804,7 @@ insert:
         if (found_next) {
                 u64 tmp;
 
-                tmp = btrfs_sector_sum_left(sums, sector_sum, total_bytes,
-                                            root->sectorsize);
+                tmp = sums->len - total_bytes;
                 tmp >>= root->fs_info->sb->s_blocksize_bits;
                 tmp = min(tmp, (next_offset - file_key.offset) >>
                                          root->fs_info->sb->s_blocksize_bits);
@@ -853,31 +825,25 @@ insert:
                 WARN_ON(1);
                 goto fail_unlock;
         }
-csum:
         leaf = path->nodes[0];
+csum:
         item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_csum_item);
-        ret = 0;
+        item_end = (struct btrfs_csum_item *)((unsigned char *)item +
+                                      btrfs_item_size_nr(leaf, path->slots[0]));
         item = (struct btrfs_csum_item *)((unsigned char *)item +
                                           csum_offset * csum_size);
 found:
-        item_end = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_csum_item);
-        item_end = (struct btrfs_csum_item *)((unsigned char *)item_end +
-                                      btrfs_item_size_nr(leaf, path->slots[0]));
-next_sector:
-
-        write_extent_buffer(leaf, &sector_sum->sum, (unsigned long)item, csum_size);
-
-        total_bytes += root->sectorsize;
-        sector_sum++;
-        if (total_bytes < sums->len) {
-                item = (struct btrfs_csum_item *)((char *)item +
-                                                  csum_size);
-                if (item < item_end && bytenr + PAGE_CACHE_SIZE ==
-                    sector_sum->bytenr) {
-                        bytenr = sector_sum->bytenr;
-                        goto next_sector;
-                }
-        }
+        ins_size = (u32)(sums->len - total_bytes) >>
+                   root->fs_info->sb->s_blocksize_bits;
+        ins_size *= csum_size;
+        ins_size = min_t(u32, (unsigned long)item_end - (unsigned long)item,
+                              ins_size);
+        write_extent_buffer(leaf, sums->sums + index, (unsigned long)item,
+                            ins_size);
+
+        ins_size /= csum_size;
+        total_bytes += ins_size * root->sectorsize;
+        index += ins_size;
 
         btrfs_mark_buffer_dirty(path->nodes[0]);
         if (total_bytes < sums->len) {
diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c
index 665c640e3ea6..81369827e514 100644
--- a/fs/btrfs/ordered-data.c
+++ b/fs/btrfs/ordered-data.c
@@ -1032,7 +1032,6 @@ int btrfs_find_ordered_sum(struct inode *inode, u64 offset, u64 disk_bytenr,
                            u32 *sum, int len)
 {
         struct btrfs_ordered_sum *ordered_sum;
-        struct btrfs_sector_sum *sector_sums;
         struct btrfs_ordered_extent *ordered;
         struct btrfs_ordered_inode_tree *tree = &BTRFS_I(inode)->ordered_tree;
         unsigned long num_sectors;
@@ -1050,18 +1049,16 @@ int btrfs_find_ordered_sum(struct inode *inode, u64 offset, u64 disk_bytenr,
                     disk_bytenr < ordered_sum->bytenr + ordered_sum->len) {
                         i = (disk_bytenr - ordered_sum->bytenr) >>
                             inode->i_sb->s_blocksize_bits;
-                        sector_sums = ordered_sum->sums + i;
                         num_sectors = ordered_sum->len >>
                                       inode->i_sb->s_blocksize_bits;
-                        for (; i < num_sectors; i++) {
-                                if (sector_sums[i].bytenr == disk_bytenr) {
-                                        sum[index] = sector_sums[i].sum;
-                                        index++;
-                                        if (index == len)
-                                                goto out;
-                                        disk_bytenr += sectorsize;
-                                }
-                        }
+                        num_sectors = min_t(int, len - index, num_sectors - i);
+                        memcpy(sum + index, ordered_sum->sums + i,
+                               num_sectors);
+
+                        index += (int)num_sectors;
+                        if (index == len)
+                                goto out;
+                        disk_bytenr += num_sectors * sectorsize;
                 }
         }
 out:
diff --git a/fs/btrfs/ordered-data.h b/fs/btrfs/ordered-data.h
index d082d43e00e5..68844d59ee6f 100644
--- a/fs/btrfs/ordered-data.h
+++ b/fs/btrfs/ordered-data.h
@@ -26,18 +26,6 @@ struct btrfs_ordered_inode_tree {
         struct rb_node *last;
 };
 
-/*
- * these are used to collect checksums done just before bios submission.
- * They are attached via a list into the ordered extent, and
- * checksum items are inserted into the tree after all the blocks in
- * the ordered extent are on disk
- */
-struct btrfs_sector_sum {
-        /* bytenr on disk */
-        u64 bytenr;
-        u32 sum;
-};
-
 struct btrfs_ordered_sum {
         /* bytenr is the start of this extent on disk */
         u64 bytenr;
@@ -45,10 +33,10 @@ struct btrfs_ordered_sum {
         /*
          * this is the length in bytes covered by the sums array below.
          */
-        unsigned long len;
+        int len;
         struct list_head list;
-        /* last field is a variable length array of btrfs_sector_sums */
-        struct btrfs_sector_sum sums[];
+        /* last field is a variable length array of csums */
+        u32 sums[];
 };
 
 /*
@@ -149,11 +137,8 @@ struct btrfs_ordered_extent {
 static inline int btrfs_ordered_sum_size(struct btrfs_root *root,
                                          unsigned long bytes)
 {
-        unsigned long num_sectors = (bytes + root->sectorsize - 1) /
-                root->sectorsize;
-        num_sectors++;
-        return sizeof(struct btrfs_ordered_sum) +
-                num_sectors * sizeof(struct btrfs_sector_sum);
+        int num_sectors = (int)DIV_ROUND_UP(bytes, root->sectorsize);
+        return sizeof(struct btrfs_ordered_sum) + num_sectors * sizeof(u32);
 }
 
 static inline void
diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
index d91f106df665..12096496cc99 100644
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -4458,10 +4458,8 @@ out:
 int btrfs_reloc_clone_csums(struct inode *inode, u64 file_pos, u64 len)
 {
         struct btrfs_ordered_sum *sums;
-        struct btrfs_sector_sum *sector_sum;
         struct btrfs_ordered_extent *ordered;
         struct btrfs_root *root = BTRFS_I(inode)->root;
-        size_t offset;
         int ret;
         u64 disk_bytenr;
         LIST_HEAD(list);
@@ -4475,19 +4473,13 @@ int btrfs_reloc_clone_csums(struct inode *inode, u64 file_pos, u64 len)
         if (ret)
                 goto out;
 
+        disk_bytenr = ordered->start;
         while (!list_empty(&list)) {
                 sums = list_entry(list.next, struct btrfs_ordered_sum, list);
                 list_del_init(&sums->list);
 
-                sector_sum = sums->sums;
-                sums->bytenr = ordered->start;
-
-                offset = 0;
-                while (offset < sums->len) {
-                        sector_sum->bytenr += ordered->start - disk_bytenr;
-                        sector_sum++;
-                        offset += root->sectorsize;
-                }
+                sums->bytenr = disk_bytenr;
+                disk_bytenr += sums->len;
 
                 btrfs_add_ordered_sum(inode, ordered, sums);
         }
diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c
index cb308a3a9300..63144e4ca9e1 100644
--- a/fs/btrfs/scrub.c
+++ b/fs/btrfs/scrub.c
@@ -2126,8 +2126,7 @@ static int scrub_find_csum(struct scrub_ctx *sctx, u64 logical, u64 len,
                            u8 *csum)
 {
         struct btrfs_ordered_sum *sum = NULL;
-        int ret = 0;
-        unsigned long i;
+        unsigned long index;
         unsigned long num_sectors;
 
         while (!list_empty(&sctx->csum_list)) {
@@ -2146,19 +2145,14 @@ static int scrub_find_csum(struct scrub_ctx *sctx, u64 logical, u64 len,
         if (!sum)
                 return 0;
 
+        index = ((u32)(logical - sum->bytenr)) / sctx->sectorsize;
         num_sectors = sum->len / sctx->sectorsize;
-        for (i = 0; i < num_sectors; ++i) {
-                if (sum->sums[i].bytenr == logical) {
-                        memcpy(csum, &sum->sums[i].sum, sctx->csum_size);
-                        ret = 1;
-                        break;
-                }
-        }
-        if (ret && i == num_sectors - 1) {
+        memcpy(csum, sum->sums + index, sctx->csum_size);
+        if (index == num_sectors - 1) {
                 list_del(&sum->list);
                 kfree(sum);
         }
-        return ret;
+        return 1;
 }
 
 /* scrub extent tries to collect up to 64 kB for each bio */