5 files changed, 168 insertions, 15 deletions

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 76fd5d7146e1..593011e5d455 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -1747,6 +1747,7 @@ again:
                                search_start, search_end, hint_byte, ins,
                                trans->alloc_exclude_start,
                                trans->alloc_exclude_nr, data);
+
         if (ret == -ENOSPC && num_bytes > min_alloc_size) {
                 num_bytes = num_bytes >> 1;
                 num_bytes = max(num_bytes, min_alloc_size);
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 88322684be6a..21597bea21fd 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -1025,7 +1025,8 @@ u64 find_lock_delalloc_range(struct extent_io_tree *tree,
 search_again:
         node = tree_search(tree, cur_start);
         if (!node) {
-                *end = (u64)-1;
+                if (!found)
+                        *end = (u64)-1;
                 goto out;
         }
 
@@ -1540,6 +1541,8 @@ static int end_bio_extent_readpage(struct bio *bio,
                                                          start, end, state);
                         if (ret == 0) {
                                 state = NULL;
+                                uptodate =
+                                        test_bit(BIO_UPTODATE, &bio->bi_flags);
                                 continue;
                         }
                 }
@@ -1555,10 +1558,11 @@ static int end_bio_extent_readpage(struct bio *bio,
                                     !(state->state & EXTENT_LOCKED))
                                         state = NULL;
                         }
-                        if (!state && uptodate) {
+                        if (!state) {
                                 spin_unlock_irqrestore(&tree->lock, flags);
-                                set_extent_uptodate(tree, start, end,
-                                                    GFP_ATOMIC);
+                                if (uptodate)
+                                        set_extent_uptodate(tree, start, end,
+                                                            GFP_ATOMIC);
                                 unlock_extent(tree, start, end, GFP_ATOMIC);
                                 goto next_io;
                         }
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 9fbda6552069..3f5525f0834c 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -356,12 +356,23 @@ out_unlock:
 int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end)
 {
         struct extent_map *em;
+        struct extent_map *split = NULL;
+        struct extent_map *split2 = NULL;
         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
         u64 len = end - start + 1;
+        int ret;
+        int testend = 1;
 
-        if (end == (u64)-1)
+        if (end == (u64)-1) {
                 len = (u64)-1;
+                testend = 0;
+        }
         while(1) {
+                if (!split)
+                        split = alloc_extent_map(GFP_NOFS);
+                if (!split2)
+                        split2 = alloc_extent_map(GFP_NOFS);
+
                 spin_lock(&em_tree->lock);
                 em = lookup_extent_mapping(em_tree, start, len);
                 if (!em) {
@@ -369,6 +380,36 @@ int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end)
                         break;
                 }
                 remove_extent_mapping(em_tree, em);
+
+                if (em->block_start < EXTENT_MAP_LAST_BYTE &&
+                    em->start < start) {
+                        split->start = em->start;
+                        split->len = start - em->start;
+                        split->block_start = em->block_start;
+                        split->bdev = em->bdev;
+                        split->flags = em->flags;
+                        ret = add_extent_mapping(em_tree, split);
+                        BUG_ON(ret);
+                        free_extent_map(split);
+                        split = split2;
+                        split2 = NULL;
+                }
+                if (em->block_start < EXTENT_MAP_LAST_BYTE &&
+                    testend && em->start + em->len > start + len) {
+                        u64 diff = start + len - em->start;
+
+                        split->start = start + len;
+                        split->len = em->start + em->len - (start + len);
+                        split->bdev = em->bdev;
+                        split->flags = em->flags;
+
+                        split->block_start = em->block_start + diff;
+
+                        ret = add_extent_mapping(em_tree, split);
+                        BUG_ON(ret);
+                        free_extent_map(split);
+                        split = NULL;
+                }
                 spin_unlock(&em_tree->lock);
 
                 /* once for us */
@@ -376,6 +417,10 @@ int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end)
                 /* once for the tree*/
                 free_extent_map(em);
         }
+        if (split)
+                free_extent_map(split);
+        if (split2)
+                free_extent_map(split2);
         return 0;
 }
 
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 5632ea760077..40f8da884090 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -122,6 +122,8 @@ static int cow_file_range(struct inode *inode, u64 start, u64 end)
         if (alloc_hint == EXTENT_MAP_INLINE)
                 goto out;
 
+        BUG_ON(num_bytes > btrfs_super_total_bytes(&root->fs_info->super_copy));
+
         while(num_bytes > 0) {
                 cur_alloc_size = min(num_bytes, root->fs_info->max_extent);
                 ret = btrfs_alloc_extent(trans, root, cur_alloc_size,
@@ -140,6 +142,11 @@ static int cow_file_range(struct inode *inode, u64 start, u64 end)
                                                ins.offset);
                 inode->i_blocks += ins.offset >> 9;
                 btrfs_check_file(root, inode);
+                if (num_bytes < cur_alloc_size) {
+                        printk("num_bytes %Lu cur_alloc %Lu\n", num_bytes,
+                               cur_alloc_size);
+                        break;
+                }
                 num_bytes -= cur_alloc_size;
                 alloc_hint = ins.objectid + ins.offset;
                 start += cur_alloc_size;
@@ -427,6 +434,7 @@ int btrfs_readpage_io_failed_hook(struct bio *failed_bio,
         struct extent_map *em;
         struct inode *inode = page->mapping->host;
         struct extent_io_tree *failure_tree = &BTRFS_I(inode)->io_failure_tree;
+        struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
         struct bio *bio;
         int num_copies;
         int ret;
@@ -434,7 +442,6 @@ int btrfs_readpage_io_failed_hook(struct bio *failed_bio,
 
         ret = get_state_private(failure_tree, start, &private);
         if (ret) {
-                size_t pg_offset = start - page_offset(page);
                 failrec = kmalloc(sizeof(*failrec), GFP_NOFS);
                 if (!failrec)
                         return -ENOMEM;
@@ -442,8 +449,13 @@ int btrfs_readpage_io_failed_hook(struct bio *failed_bio,
                 failrec->len = end - start + 1;
                 failrec->last_mirror = 0;
 
-                em = btrfs_get_extent(inode, NULL, pg_offset, start,
-                                      failrec->len, 0);
+                spin_lock(&em_tree->lock);
+                em = lookup_extent_mapping(em_tree, start, failrec->len);
+                if (em->start > start || em->start + em->len < start) {
+                        free_extent_map(em);
+                        em = NULL;
+                }
+                spin_unlock(&em_tree->lock);
 
                 if (!em || IS_ERR(em)) {
                         kfree(failrec);
@@ -559,6 +571,8 @@ zeroit:
         flush_dcache_page(page);
         kunmap_atomic(kaddr, KM_IRQ0);
         local_irq_restore(flags);
+        if (private == 0)
+                return 0;
         return -EIO;
 }
 
@@ -908,8 +922,9 @@ static int btrfs_truncate_in_trans(struct btrfs_trans_handle *trans,
         int pending_del_nr = 0;
         int pending_del_slot = 0;
         int extent_type = -1;
+        u64 mask = root->sectorsize - 1;
 
-        btrfs_drop_extent_cache(inode, inode->i_size, (u64)-1);
+        btrfs_drop_extent_cache(inode, inode->i_size & (~mask), (u64)-1);
         path = btrfs_alloc_path();
         path->reada = -1;
         BUG_ON(!path);
@@ -1212,7 +1227,7 @@ static int btrfs_setattr(struct dentry *dentry, struct iattr *attr)
                                                        hole_start, 0, 0,
                                                        hole_size);
                         btrfs_drop_extent_cache(inode, hole_start,
-                                                hole_size - 1);
+                                                (u64)-1);
                         btrfs_check_file(root, inode);
                 }
                 btrfs_end_transaction(trans, root);
@@ -2083,6 +2098,68 @@ out_unlock:
         return err;
 }
 
+static int merge_extent_mapping(struct extent_map_tree *em_tree,
+                                struct extent_map *existing,
+                                struct extent_map *em)
+{
+        u64 start_diff;
+        u64 new_end;
+        int ret = 0;
+        int real_blocks = existing->block_start < EXTENT_MAP_LAST_BYTE;
+
+        if (real_blocks && em->block_start >= EXTENT_MAP_LAST_BYTE)
+                goto invalid;
+
+        if (!real_blocks && em->block_start != existing->block_start)
+                goto invalid;
+
+        new_end = max(existing->start + existing->len, em->start + em->len);
+
+        if (existing->start >= em->start) {
+                if (em->start + em->len < existing->start)
+                        goto invalid;
+
+                start_diff = existing->start - em->start;
+                if (real_blocks && em->block_start + start_diff !=
+                    existing->block_start)
+                        goto invalid;
+
+                em->len = new_end - em->start;
+
+                remove_extent_mapping(em_tree, existing);
+                /* free for the tree */
+                free_extent_map(existing);
+                ret = add_extent_mapping(em_tree, em);
+
+        } else if (em->start > existing->start) {
+
+                if (existing->start + existing->len < em->start)
+                        goto invalid;
+
+                start_diff = em->start - existing->start;
+                if (real_blocks && existing->block_start + start_diff !=
+                    em->block_start)
+                        goto invalid;
+
+                remove_extent_mapping(em_tree, existing);
+                em->block_start = existing->block_start;
+                em->start = existing->start;
+                em->len = new_end - existing->start;
+                free_extent_map(existing);
+
+                ret = add_extent_mapping(em_tree, em);
+        } else {
+                goto invalid;
+        }
+        return ret;
+
+invalid:
+        printk("invalid extent map merge [%Lu %Lu %Lu] [%Lu %Lu %Lu]\n",
+               existing->start, existing->len, existing->block_start,
+               em->start, em->len, em->block_start);
+        return -EIO;
+}
+
 struct extent_map *btrfs_get_extent(struct inode *inode, struct page *page,
                                     size_t pg_offset, u64 start, u64 len,
                                     int create)
@@ -2267,12 +2344,35 @@ insert:
         err = 0;
         spin_lock(&em_tree->lock);
         ret = add_extent_mapping(em_tree, em);
+
+        /* it is possible that someone inserted the extent into the tree
+         * while we had the lock dropped.  It is also possible that
+         * an overlapping map exists in the tree
+         */
         if (ret == -EEXIST) {
-                free_extent_map(em);
-                em = lookup_extent_mapping(em_tree, start, len);
-                if (!em) {
-                        err = -EIO;
-                        printk("failing to insert %Lu %Lu\n", start, len);
+                struct extent_map *existing;
+                existing = lookup_extent_mapping(em_tree, start, len);
+                if (!existing) {
+                        existing = lookup_extent_mapping(em_tree, em->start,
+                                                         em->len);
+                        if (existing) {
+                                err = merge_extent_mapping(em_tree, existing,
+                                                           em);
+                                free_extent_map(existing);
+                                if (err) {
+                                        free_extent_map(em);
+                                        em = NULL;
+                                }
+                        } else {
+                                err = -EIO;
+                                printk("failing to insert %Lu %Lu\n",
+                                       start, len);
+                                free_extent_map(em);
+                                em = NULL;
+                        }
+                } else {
+                        free_extent_map(em);
+                        em = existing;
                 }
         }
         spin_unlock(&em_tree->lock);
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index e6417a573d44..0e658c1d8211 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -883,6 +883,9 @@ again:
         spin_lock(&em_tree->lock);
         em = lookup_extent_mapping(em_tree, logical, *length);
         spin_unlock(&em_tree->lock);
+        if (!em) {
+                printk("unable to find logical %Lu\n", logical);
+        }
         BUG_ON(!em);
 
         BUG_ON(em->start > logical || em->start + em->len < logical);