btrfs: use proper type for failrec in extent_state

We use the private member of extent_state to store the failrec and play
pointless pointer games.

Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 2e7c97a..f3910ac 100644 (file)
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -232,7 +232,7 @@ static struct extent_state *alloc_extent_state(gfp_t mask)
        if (!state)
                return state;
        state->state = 0;
-       state->private = 0;
+       state->failrec = NULL;
        RB_CLEAR_NODE(&state->rb_node);
        btrfs_leak_debug_add(&state->leak_list, &states);
        atomic_set(&state->refs, 1);
@@ -1844,7 +1844,8 @@ out:
  * set the private field for a given byte offset in the tree.  If there isn't
  * an extent_state there already, this does nothing.
  */
-static int set_state_private(struct extent_io_tree *tree, u64 start, u64 private)
+static int set_state_failrec(struct extent_io_tree *tree, u64 start,
+               struct io_failure_record *failrec)
 {
        struct rb_node *node;
        struct extent_state *state;
@@ -1865,13 +1866,14 @@ static int set_state_private(struct extent_io_tree *tree, u64 start, u64 private
                ret = -ENOENT;
                goto out;
        }
-       state->private = private;
+       state->failrec = failrec;
 out:
        spin_unlock(&tree->lock);
        return ret;
 }
 
-int get_state_private(struct extent_io_tree *tree, u64 start, u64 *private)
+static int get_state_failrec(struct extent_io_tree *tree, u64 start,
+               struct io_failure_record **failrec)
 {
        struct rb_node *node;
        struct extent_state *state;
@@ -1892,7 +1894,7 @@ int get_state_private(struct extent_io_tree *tree, u64 start, u64 *private)
                ret = -ENOENT;
                goto out;
        }
-       *private = state->private;
+       *failrec = state->failrec;
 out:
        spin_unlock(&tree->lock);
        return ret;
@@ -1972,7 +1974,7 @@ int free_io_failure(struct inode *inode, struct io_failure_record *rec)
        int err = 0;
        struct extent_io_tree *failure_tree = &BTRFS_I(inode)->io_failure_tree;
 
-       set_state_private(failure_tree, rec->start, 0);
+       set_state_failrec(failure_tree, rec->start, NULL);
        ret = clear_extent_bits(failure_tree, rec->start,
                                rec->start + rec->len - 1,
                                EXTENT_LOCKED | EXTENT_DIRTY, GFP_NOFS);
@@ -2089,7 +2091,6 @@ int clean_io_failure(struct inode *inode, u64 start, struct page *page,
                     unsigned int pg_offset)
 {
        u64 private;
-       u64 private_failure;
        struct io_failure_record *failrec;
        struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
        struct extent_state *state;
@@ -2102,12 +2103,11 @@ int clean_io_failure(struct inode *inode, u64 start, struct page *page,
        if (!ret)
                return 0;
 
-       ret = get_state_private(&BTRFS_I(inode)->io_failure_tree, start,
-                               &private_failure);
+       ret = get_state_failrec(&BTRFS_I(inode)->io_failure_tree, start,
+                       &failrec);
        if (ret)
                return 0;
 
-       failrec = (struct io_failure_record *)(unsigned long) private_failure;
        BUG_ON(!failrec->this_mirror);
 
        if (failrec->in_validation) {
@@ -2167,7 +2167,7 @@ void btrfs_free_io_failure_record(struct inode *inode, u64 start, u64 end)
 
                next = next_state(state);
 
-               failrec = (struct io_failure_record *)(unsigned long)state->private;
+               failrec = state->failrec;
                free_extent_state(state);
                kfree(failrec);
 
@@ -2177,10 +2177,9 @@ void btrfs_free_io_failure_record(struct inode *inode, u64 start, u64 end)
 }
 
 int btrfs_get_io_failure_record(struct inode *inode, u64 start, u64 end,
-                               struct io_failure_record **failrec_ret)
+               struct io_failure_record **failrec_ret)
 {
        struct io_failure_record *failrec;
-       u64 private;
        struct extent_map *em;
        struct extent_io_tree *failure_tree = &BTRFS_I(inode)->io_failure_tree;
        struct extent_io_tree *tree = &BTRFS_I(inode)->io_tree;
@@ -2188,7 +2187,7 @@ int btrfs_get_io_failure_record(struct inode *inode, u64 start, u64 end,
        int ret;
        u64 logical;
 
-       ret = get_state_private(failure_tree, start, &private);
+       ret = get_state_failrec(failure_tree, start, &failrec);
        if (ret) {
                failrec = kzalloc(sizeof(*failrec), GFP_NOFS);
                if (!failrec)
@@ -2237,8 +2236,7 @@ int btrfs_get_io_failure_record(struct inode *inode, u64 start, u64 end,
                ret = set_extent_bits(failure_tree, start, end,
                                        EXTENT_LOCKED | EXTENT_DIRTY, GFP_NOFS);
                if (ret >= 0)
-                       ret = set_state_private(failure_tree, start,
-                                               (u64)(unsigned long)failrec);
+                       ret = set_state_failrec(failure_tree, start, failrec);
                /* set the bits in the inode's tree */
                if (ret >= 0)
                        ret = set_extent_bits(tree, start, end, EXTENT_DAMAGED,
@@ -2248,7 +2246,6 @@ int btrfs_get_io_failure_record(struct inode *inode, u64 start, u64 end,
                        return ret;
                }
        } else {
-               failrec = (struct io_failure_record *)(unsigned long)private;
                pr_debug("Get IO Failure Record: (found) logical=%llu, start=%llu, len=%llu, validation=%d\n",
                         failrec->logical, failrec->start, failrec->len,
                         failrec->in_validation);

diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h
index 0377413..98a25a1 100644 (file)
--- a/fs/btrfs/extent_io.h
+++ b/fs/btrfs/extent_io.h
@@ -62,6 +62,7 @@
 struct extent_state;
 struct btrfs_root;
 struct btrfs_io_bio;
+struct io_failure_record;
 
 typedef        int (extent_submit_bio_hook_t)(struct inode *inode, int rw,
                                       struct bio *bio, int mirror_num,
@@ -112,8 +113,7 @@ struct extent_state {
        atomic_t refs;
        unsigned state;
 
-       /* for use by the FS */
-       u64 private;
+       struct io_failure_record *failrec;
 
 #ifdef CONFIG_BTRFS_DEBUG
        struct list_head leak_list;
@@ -345,7 +345,6 @@ int extent_readpages(struct extent_io_tree *tree,
                     get_extent_t get_extent);
 int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
                __u64 start, __u64 len, get_extent_t *get_extent);
-int get_state_private(struct extent_io_tree *tree, u64 start, u64 *private);
 void set_page_extent_mapped(struct page *page);
 
 struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info,