1 files changed, 280 insertions, 22 deletions

diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 75899a01dded..c6a22d783c35 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -40,6 +40,263 @@
 #include "locking.h"
 #include "compat.h"
 
+/*
+ * when auto defrag is enabled we
+ * queue up these defrag structs to remember which
+ * inodes need defragging passes
+ */
+struct inode_defrag {
+        struct rb_node rb_node;
+        /* objectid */
+        u64 ino;
+        /*
+         * transid where the defrag was added, we search for
+         * extents newer than this
+         */
+        u64 transid;
+
+        /* root objectid */
+        u64 root;
+
+        /* last offset we were able to defrag */
+        u64 last_offset;
+
+        /* if we've wrapped around back to zero once already */
+        int cycled;
+};
+
+/* pop a record for an inode into the defrag tree.  The lock
+ * must be held already
+ *
+ * If you're inserting a record for an older transid than an
+ * existing record, the transid already in the tree is lowered
+ *
+ * If an existing record is found the defrag item you
+ * pass in is freed
+ */
+static int __btrfs_add_inode_defrag(struct inode *inode,
+                                    struct inode_defrag *defrag)
+{
+        struct btrfs_root *root = BTRFS_I(inode)->root;
+        struct inode_defrag *entry;
+        struct rb_node **p;
+        struct rb_node *parent = NULL;
+
+        p = &root->fs_info->defrag_inodes.rb_node;
+        while (*p) {
+                parent = *p;
+                entry = rb_entry(parent, struct inode_defrag, rb_node);
+
+                if (defrag->ino < entry->ino)
+                        p = &parent->rb_left;
+                else if (defrag->ino > entry->ino)
+                        p = &parent->rb_right;
+                else {
+                        /* if we're reinserting an entry for
+                         * an old defrag run, make sure to
+                         * lower the transid of our existing record
+                         */
+                        if (defrag->transid < entry->transid)
+                                entry->transid = defrag->transid;
+                        if (defrag->last_offset > entry->last_offset)
+                                entry->last_offset = defrag->last_offset;
+                        goto exists;
+                }
+        }
+        BTRFS_I(inode)->in_defrag = 1;
+        rb_link_node(&defrag->rb_node, parent, p);
+        rb_insert_color(&defrag->rb_node, &root->fs_info->defrag_inodes);
+        return 0;
+
+exists:
+        kfree(defrag);
+        return 0;
+
+}
+
+/*
+ * insert a defrag record for this inode if auto defrag is
+ * enabled
+ */
+int btrfs_add_inode_defrag(struct btrfs_trans_handle *trans,
+                           struct inode *inode)
+{
+        struct btrfs_root *root = BTRFS_I(inode)->root;
+        struct inode_defrag *defrag;
+        int ret = 0;
+        u64 transid;
+
+        if (!btrfs_test_opt(root, AUTO_DEFRAG))
+                return 0;
+
+        if (root->fs_info->closing)
+                return 0;
+
+        if (BTRFS_I(inode)->in_defrag)
+                return 0;
+
+        if (trans)
+                transid = trans->transid;
+        else
+                transid = BTRFS_I(inode)->root->last_trans;
+
+        defrag = kzalloc(sizeof(*defrag), GFP_NOFS);
+        if (!defrag)
+                return -ENOMEM;
+
+        defrag->ino = inode->i_ino;
+        defrag->transid = transid;
+        defrag->root = root->root_key.objectid;
+
+        spin_lock(&root->fs_info->defrag_inodes_lock);
+        if (!BTRFS_I(inode)->in_defrag)
+                ret = __btrfs_add_inode_defrag(inode, defrag);
+        spin_unlock(&root->fs_info->defrag_inodes_lock);
+        return ret;
+}
+
+/*
+ * must be called with the defrag_inodes lock held
+ */
+struct inode_defrag *btrfs_find_defrag_inode(struct btrfs_fs_info *info, u64 ino,
+                                             struct rb_node **next)
+{
+        struct inode_defrag *entry = NULL;
+        struct rb_node *p;
+        struct rb_node *parent = NULL;
+
+        p = info->defrag_inodes.rb_node;
+        while (p) {
+                parent = p;
+                entry = rb_entry(parent, struct inode_defrag, rb_node);
+
+                if (ino < entry->ino)
+                        p = parent->rb_left;
+                else if (ino > entry->ino)
+                        p = parent->rb_right;
+                else
+                        return entry;
+        }
+
+        if (next) {
+                while (parent && ino > entry->ino) {
+                        parent = rb_next(parent);
+                        entry = rb_entry(parent, struct inode_defrag, rb_node);
+                }
+                *next = parent;
+        }
+        return NULL;
+}
+
+/*
+ * run through the list of inodes in the FS that need
+ * defragging
+ */
+int btrfs_run_defrag_inodes(struct btrfs_fs_info *fs_info)
+{
+        struct inode_defrag *defrag;
+        struct btrfs_root *inode_root;
+        struct inode *inode;
+        struct rb_node *n;
+        struct btrfs_key key;
+        struct btrfs_ioctl_defrag_range_args range;
+        u64 first_ino = 0;
+        int num_defrag;
+        int defrag_batch = 1024;
+
+        memset(&range, 0, sizeof(range));
+        range.len = (u64)-1;
+
+        atomic_inc(&fs_info->defrag_running);
+        spin_lock(&fs_info->defrag_inodes_lock);
+        while(1) {
+                n = NULL;
+
+                /* find an inode to defrag */
+                defrag = btrfs_find_defrag_inode(fs_info, first_ino, &n);
+                if (!defrag) {
+                        if (n)
+                                defrag = rb_entry(n, struct inode_defrag, rb_node);
+                        else if (first_ino) {
+                                first_ino = 0;
+                                continue;
+                        } else {
+                                break;
+                        }
+                }
+
+                /* remove it from the rbtree */
+                first_ino = defrag->ino + 1;
+                rb_erase(&defrag->rb_node, &fs_info->defrag_inodes);
+
+                if (fs_info->closing)
+                        goto next_free;
+
+                spin_unlock(&fs_info->defrag_inodes_lock);
+
+                /* get the inode */
+                key.objectid = defrag->root;
+                btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
+                key.offset = (u64)-1;
+                inode_root = btrfs_read_fs_root_no_name(fs_info, &key);
+                if (IS_ERR(inode_root))
+                        goto next;
+
+                key.objectid = defrag->ino;
+                btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
+                key.offset = 0;
+
+                inode = btrfs_iget(fs_info->sb, &key, inode_root, NULL);
+                if (IS_ERR(inode))
+                        goto next;
+
+                /* do a chunk of defrag */
+                BTRFS_I(inode)->in_defrag = 0;
+                range.start = defrag->last_offset;
+                num_defrag = btrfs_defrag_file(inode, NULL, &range, defrag->transid,
+                                               defrag_batch);
+                /*
+                 * if we filled the whole defrag batch, there
+                 * must be more work to do.  Queue this defrag
+                 * again
+                 */
+                if (num_defrag == defrag_batch) {
+                        defrag->last_offset = range.start;
+                        __btrfs_add_inode_defrag(inode, defrag);
+                        /*
+                         * we don't want to kfree defrag, we added it back to
+                         * the rbtree
+                         */
+                        defrag = NULL;
+                } else if (defrag->last_offset && !defrag->cycled) {
+                        /*
+                         * we didn't fill our defrag batch, but
+                         * we didn't start at zero.  Make sure we loop
+                         * around to the start of the file.
+                         */
+                        defrag->last_offset = 0;
+                        defrag->cycled = 1;
+                        __btrfs_add_inode_defrag(inode, defrag);
+                        defrag = NULL;
+                }
+
+                iput(inode);
+next:
+                spin_lock(&fs_info->defrag_inodes_lock);
+next_free:
+                kfree(defrag);
+        }
+        spin_unlock(&fs_info->defrag_inodes_lock);
+
+        atomic_dec(&fs_info->defrag_running);
+
+        /*
+         * during unmount, we use the transaction_wait queue to
+         * wait for the defragger to stop
+         */
+        wake_up(&fs_info->transaction_wait);
+        return 0;
+}
 
 /* simple helper to fault in pages and copy.  This should go away
  * and be replaced with calls into generic code.
@@ -191,9 +448,9 @@ int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end,
         }
         while (1) {
                 if (!split)
-                        split = alloc_extent_map(GFP_NOFS);
+                        split = alloc_extent_map();
                 if (!split2)
-                        split2 = alloc_extent_map(GFP_NOFS);
+                        split2 = alloc_extent_map();
                 BUG_ON(!split || !split2);
 
                 write_lock(&em_tree->lock);
@@ -298,6 +555,7 @@ int btrfs_drop_extents(struct btrfs_trans_handle *trans, struct inode *inode,
         struct btrfs_path *path;
         struct btrfs_key key;
         struct btrfs_key new_key;
+        u64 ino = btrfs_ino(inode);
         u64 search_start = start;
         u64 disk_bytenr = 0;
         u64 num_bytes = 0;
@@ -318,14 +576,14 @@ int btrfs_drop_extents(struct btrfs_trans_handle *trans, struct inode *inode,
 
         while (1) {
                 recow = 0;
-                ret = btrfs_lookup_file_extent(trans, root, path, inode->i_ino,
+                ret = btrfs_lookup_file_extent(trans, root, path, ino,
                                                search_start, -1);
                 if (ret < 0)
                         break;
                 if (ret > 0 && path->slots[0] > 0 && search_start == start) {
                         leaf = path->nodes[0];
                         btrfs_item_key_to_cpu(leaf, &key, path->slots[0] - 1);
-                        if (key.objectid == inode->i_ino &&
+                        if (key.objectid == ino &&
                             key.type == BTRFS_EXTENT_DATA_KEY)
                                 path->slots[0]--;
                 }
@@ -346,7 +604,7 @@ next_slot:
                 }
 
                 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
-                if (key.objectid > inode->i_ino ||
+                if (key.objectid > ino ||
                     key.type > BTRFS_EXTENT_DATA_KEY || key.offset >= end)
                         break;
 
@@ -376,7 +634,7 @@ next_slot:
 
                 search_start = max(key.offset, start);
                 if (recow) {
-                        btrfs_release_path(root, path);
+                        btrfs_release_path(path);
                         continue;
                 }
 
@@ -393,7 +651,7 @@ next_slot:
                         ret = btrfs_duplicate_item(trans, root, path,
                                                    &new_key);
                         if (ret == -EAGAIN) {
-                                btrfs_release_path(root, path);
+                                btrfs_release_path(path);
                                 continue;
                         }
                         if (ret < 0)
@@ -516,7 +774,7 @@ next_slot:
                         del_nr = 0;
                         del_slot = 0;
 
-                        btrfs_release_path(root, path);
+                        btrfs_release_path(path);
                         continue;
                 }
 
@@ -592,6 +850,7 @@ int btrfs_mark_extent_written(struct btrfs_trans_handle *trans,
         int del_slot = 0;
         int recow;
         int ret;
+        u64 ino = btrfs_ino(inode);
 
         btrfs_drop_extent_cache(inode, start, end - 1, 0);
 
@@ -600,7 +859,7 @@ int btrfs_mark_extent_written(struct btrfs_trans_handle *trans,
 again:
         recow = 0;
         split = start;
-        key.objectid = inode->i_ino;
+        key.objectid = ino;
         key.type = BTRFS_EXTENT_DATA_KEY;
         key.offset = split;
 
@@ -612,8 +871,7 @@ again:
 
         leaf = path->nodes[0];
         btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
-        BUG_ON(key.objectid != inode->i_ino ||
-               key.type != BTRFS_EXTENT_DATA_KEY);
+        BUG_ON(key.objectid != ino || key.type != BTRFS_EXTENT_DATA_KEY);
         fi = btrfs_item_ptr(leaf, path->slots[0],
                             struct btrfs_file_extent_item);
         BUG_ON(btrfs_file_extent_type(leaf, fi) !=
@@ -630,7 +888,7 @@ again:
                 other_start = 0;
                 other_end = start;
                 if (extent_mergeable(leaf, path->slots[0] - 1,
-                                     inode->i_ino, bytenr, orig_offset,
+                                     ino, bytenr, orig_offset,
                                      &other_start, &other_end)) {
                         new_key.offset = end;
                         btrfs_set_item_key_safe(trans, root, path, &new_key);
@@ -653,7 +911,7 @@ again:
                 other_start = end;
                 other_end = 0;
                 if (extent_mergeable(leaf, path->slots[0] + 1,
-                                     inode->i_ino, bytenr, orig_offset,
+                                     ino, bytenr, orig_offset,
                                      &other_start, &other_end)) {
                         fi = btrfs_item_ptr(leaf, path->slots[0],
                                             struct btrfs_file_extent_item);
@@ -681,7 +939,7 @@ again:
                 new_key.offset = split;
                 ret = btrfs_duplicate_item(trans, root, path, &new_key);
                 if (ret == -EAGAIN) {
-                        btrfs_release_path(root, path);
+                        btrfs_release_path(path);
                         goto again;
                 }
                 BUG_ON(ret < 0);
@@ -702,7 +960,7 @@ again:
 
                 ret = btrfs_inc_extent_ref(trans, root, bytenr, num_bytes, 0,
                                            root->root_key.objectid,
-                                           inode->i_ino, orig_offset);
+                                           ino, orig_offset);
                 BUG_ON(ret);
 
                 if (split == start) {
@@ -718,10 +976,10 @@ again:
         other_start = end;
         other_end = 0;
         if (extent_mergeable(leaf, path->slots[0] + 1,
-                             inode->i_ino, bytenr, orig_offset,
+                             ino, bytenr, orig_offset,
                              &other_start, &other_end)) {
                 if (recow) {
-                        btrfs_release_path(root, path);
+                        btrfs_release_path(path);
                         goto again;
                 }
                 extent_end = other_end;
@@ -729,16 +987,16 @@ again:
                 del_nr++;
                 ret = btrfs_free_extent(trans, root, bytenr, num_bytes,
                                         0, root->root_key.objectid,
-                                        inode->i_ino, orig_offset);
+                                        ino, orig_offset);
                 BUG_ON(ret);
         }
         other_start = 0;
         other_end = start;
         if (extent_mergeable(leaf, path->slots[0] - 1,
-                             inode->i_ino, bytenr, orig_offset,
+                             ino, bytenr, orig_offset,
                              &other_start, &other_end)) {
                 if (recow) {
-                        btrfs_release_path(root, path);
+                        btrfs_release_path(path);
                         goto again;
                 }
                 key.offset = other_start;
@@ -746,7 +1004,7 @@ again:
                 del_nr++;
                 ret = btrfs_free_extent(trans, root, bytenr, num_bytes,
                                         0, root->root_key.objectid,
-                                        inode->i_ino, orig_offset);
+                                        ino, orig_offset);
                 BUG_ON(ret);
         }
         if (del_nr == 0) {
@@ -1375,7 +1633,7 @@ static long btrfs_fallocate(struct file *file, int mode,
         while (1) {
                 em = btrfs_get_extent(inode, NULL, 0, cur_offset,
                                       alloc_end - cur_offset, 0);
-                BUG_ON(IS_ERR(em) || !em);
+                BUG_ON(IS_ERR_OR_NULL(em));
                 last_byte = min(extent_map_end(em), alloc_end);
                 last_byte = (last_byte + mask) & ~mask;
                 if (em->block_start == EXTENT_MAP_HOLE ||