Merge remote-tracking branch 'lsk/v4.4/topic/mm-kaslr' into linux-linaro-lsk-v4.4

[firefly-linux-kernel-4.4.55.git] / drivers / md / dm-thin-metadata.c

diff --git a/drivers/md/dm-thin-metadata.c b/drivers/md/dm-thin-metadata.c
index 1fa45695b68a4eb6ed3db388d30f6e88f06fee21..911ada64336407fe15f8b5d6fc2df026cf1649cc 100644 (file)
--- a/drivers/md/dm-thin-metadata.c
+++ b/drivers/md/dm-thin-metadata.c
@@ -1206,6 +1206,12 @@ static int __reserve_metadata_snap(struct dm_pool_metadata *pmd)
        struct dm_block *copy, *sblock;
        dm_block_t held_root;
 
+       /*
+        * We commit to ensure the btree roots which we increment in a
+        * moment are up to date.
+        */
+       __commit_transaction(pmd);
+
        /*
         * Copy the superblock.
         */
@@ -1538,7 +1544,7 @@ static int __remove(struct dm_thin_device *td, dm_block_t block)
 static int __remove_range(struct dm_thin_device *td, dm_block_t begin, dm_block_t end)
 {
        int r;
-       unsigned count;
+       unsigned count, total_count = 0;
        struct dm_pool_metadata *pmd = td->pmd;
        dm_block_t keys[1] = { td->id };
        __le64 value;
@@ -1561,11 +1567,29 @@ static int __remove_range(struct dm_thin_device *td, dm_block_t begin, dm_block_
        if (r)
                return r;
 
-       r = dm_btree_remove_leaves(&pmd->bl_info, mapping_root, &begin, end, &mapping_root, &count);
-       if (r)
-               return r;
+       /*
+        * Remove leaves stops at the first unmapped entry, so we have to
+        * loop round finding mapped ranges.
+        */
+       while (begin < end) {
+               r = dm_btree_lookup_next(&pmd->bl_info, mapping_root, &begin, &begin, &value);
+               if (r == -ENODATA)
+                       break;
+
+               if (r)
+                       return r;
+
+               if (begin >= end)
+                       break;
+
+               r = dm_btree_remove_leaves(&pmd->bl_info, mapping_root, &begin, end, &mapping_root, &count);
+               if (r)
+                       return r;
 
-       td->mapped_blocks -= count;
+               total_count += count;
+       }
+
+       td->mapped_blocks -= total_count;
        td->changed = 1;
 
        /*
@@ -1919,5 +1943,8 @@ bool dm_pool_metadata_needs_check(struct dm_pool_metadata *pmd)
 
 void dm_pool_issue_prefetches(struct dm_pool_metadata *pmd)
 {
-       dm_tm_issue_prefetches(pmd->tm);
+       down_read(&pmd->root_lock);
+       if (!pmd->fail_io)
+               dm_tm_issue_prefetches(pmd->tm);
+       up_read(&pmd->root_lock);
 }