ext2 reservations

Val's cross-port of the ext3 reservations code into ext2.

[mbligh@mbligh.org: Small type error for printk
[akpm@linux-foundation.org: fix types, sync with ext3]
[mbligh@mbligh.org: Bring ext2 reservations code in line with latest ext3]
[akpm@linux-foundation.org: kill noisy printk]
[akpm@linux-foundation.org: remember to dirty the gdp's block]
[akpm@linux-foundation.org: cross-port the missed 5dea5176e5c32ef9f0d1a41d28427b3bf6881b3a]
[akpm@linux-foundation.org: cross-port e6022603b9aa7d61d20b392e69edcdbbc1789969]
[akpm@linux-foundation.org: Port the omitted 08fb306fe63d98eb86e3b16f4cc21816fa47f18e]
[akpm@linux-foundation.org: Backport the missed 20acaa18d0c002fec180956f87adeb3f11f635a6]
[akpm@linux-foundation.org: fixes]
[cmm@us.ibm.com: fix reservation extension]
[bunk@stusta.de: make ext2_get_blocks() static]
[hugh@veritas.com: fix hang]
[hugh@veritas.com: ext2_new_blocks should reset the reservation window size]
[hugh@veritas.com: ext2 balloc: fix off-by-one against rsv_end]
[hugh@veritas.com: grp_goal 0 is a genuine goal (unlike -1), so ext2_try_to_allocate_with_rsv should treat it as such]
[hugh@veritas.com: rbtree usage cleanup]
[pbadari@us.ibm.com: Fix for ext2 reservation]
[bunk@kernel.org: remove fs/ext2/balloc.c:reserve_blocks()]
[hugh@veritas.com: ext2 balloc: use io_error label]
Cc: "Martin J. Bligh" <mbligh@mbligh.org>
Cc: Valerie Henson <val_henson@linux.intel.com>
Cc: Mingming Cao <cmm@us.ibm.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 50 insertions, 0 deletions

diff --git a/include/linux/ext2_fs_sb.h b/include/linux/ext2_fs_sb.h
index 199ef37b0a19..f273415ab6f1 100644
--- a/include/linux/ext2_fs_sb.h
+++ b/include/linux/ext2_fs_sb.h
@@ -18,6 +18,52 @@
 
 #include <linux/blockgroup_lock.h>
 #include <linux/percpu_counter.h>
+#include <linux/rbtree.h>
+
+/* XXX Here for now... not interested in restructing headers JUST now */
+
+/* data type for block offset of block group */
+typedef int ext2_grpblk_t;
+
+/* data type for filesystem-wide blocks number */
+typedef unsigned long ext2_fsblk_t;
+
+#define E2FSBLK "%lu"
+
+struct ext2_reserve_window {
+        ext2_fsblk_t            _rsv_start;     /* First byte reserved */
+        ext2_fsblk_t            _rsv_end;       /* Last byte reserved or 0 */
+};
+
+struct ext2_reserve_window_node {
+        struct rb_node          rsv_node;
+        __u32                   rsv_goal_size;
+        __u32                   rsv_alloc_hit;
+        struct ext2_reserve_window      rsv_window;
+};
+
+struct ext2_block_alloc_info {
+        /* information about reservation window */
+        struct ext2_reserve_window_node rsv_window_node;
+        /*
+         * was i_next_alloc_block in ext2_inode_info
+         * is the logical (file-relative) number of the
+         * most-recently-allocated block in this file.
+         * We use this for detecting linearly ascending allocation requests.
+         */
+        __u32                   last_alloc_logical_block;
+        /*
+         * Was i_next_alloc_goal in ext2_inode_info
+         * is the *physical* companion to i_next_alloc_block.
+         * it the the physical block number of the block which was most-recentl
+         * allocated to this file.  This give us the goal (target) for the next
+         * allocation when we detect linearly ascending requests.
+         */
+        ext2_fsblk_t            last_alloc_physical_block;
+};
+
+#define rsv_start rsv_window._rsv_start
+#define rsv_end rsv_window._rsv_end
 
 /*
  * second extended-fs super-block data in memory
@@ -56,6 +102,10 @@ struct ext2_sb_info {
         struct percpu_counter s_freeinodes_counter;
         struct percpu_counter s_dirs_counter;
         struct blockgroup_lock s_blockgroup_lock;
+        /* root of the per fs reservation window tree */
+        spinlock_t s_rsv_window_lock;
+        struct rb_root s_rsv_window_root;
+        struct ext2_reserve_window_node s_rsv_window_head;
 };
 
 #endif  /* _LINUX_EXT2_FS_SB */