Btrfs: do less aggressive btree readahead

[safe/jmp/linux-2.6] / fs / btrfs / volumes.h

diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
index 4a47dcb..86c44e9 100644 (file)
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -18,13 +18,34 @@
 
 #ifndef __BTRFS_VOLUMES_
 #define __BTRFS_VOLUMES_
+
+#include <linux/bio.h>
+#include "async-thread.h"
+
+struct buffer_head;
 struct btrfs_device {
        struct list_head dev_list;
+       struct list_head dev_alloc_list;
+       struct btrfs_fs_devices *fs_devices;
        struct btrfs_root *dev_root;
-       struct btrfs_key dev_key;
+       struct bio *pending_bios;
+       struct bio *pending_bio_tail;
+       int running_pending;
+       u64 generation;
+
+       int barriers;
+       int writeable;
+       int in_fs_metadata;
+
+       spinlock_t io_lock;
 
        struct block_device *bdev;
 
+       /* the mode sent to open_bdev_exclusive */
+       fmode_t mode;
+
+       char *name;
+
        /* the internal btrfs device id */
        u64 devid;
 
@@ -43,36 +64,99 @@ struct btrfs_device {
        /* minimal io size for this device */
        u32 sector_size;
 
-       /* the kernel device number */
-       u64 rdev;
-
        /* type and info about this device */
        u64 type;
 
-       /* partition number, 0 for whole dev */
-       int partition;
+       /* physical drive uuid (or lvm uuid) */
+       u8 uuid[BTRFS_UUID_SIZE];
+
+       struct btrfs_work work;
+};
 
-       /* length of the name data at the end of the item */
-       int name_len;
+struct btrfs_fs_devices {
+       u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */
 
-       /* physical drive uuid (or lvm uuid) */
-       u8 uuid[BTRFS_DEV_UUID_SIZE];
+       /* the device with this id has the most recent coyp of the super */
+       u64 latest_devid;
+       u64 latest_trans;
+       u64 num_devices;
+       u64 open_devices;
+       u64 rw_devices;
+       u64 total_rw_bytes;
+       struct block_device *latest_bdev;
+       /* all of the devices in the FS */
+       struct list_head devices;
 
-       char *name;
+       /* devices not currently being allocated */
+       struct list_head alloc_list;
+       struct list_head list;
+
+       struct btrfs_fs_devices *seed;
+       int seeding;
+
+       int opened;
 };
 
+struct btrfs_bio_stripe {
+       struct btrfs_device *dev;
+       u64 physical;
+};
+
+struct btrfs_multi_bio {
+       atomic_t stripes_pending;
+       bio_end_io_t *end_io;
+       struct bio *orig_bio;
+       void *private;
+       atomic_t error;
+       int max_errors;
+       int num_stripes;
+       struct btrfs_bio_stripe stripes[];
+};
+
+#define btrfs_multi_bio_size(n) (sizeof(struct btrfs_multi_bio) + \
+                           (sizeof(struct btrfs_bio_stripe) * (n)))
+
 int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans,
                           struct btrfs_device *device,
-                          u64 owner, u64 num_bytes, u64 *start);
-int btrfs_map_block(struct btrfs_mapping_tree *map_tree,
-                   u64 logical, u64 *phys, u64 *length,
-                   struct btrfs_device **dev);
+                          u64 chunk_tree, u64 chunk_objectid,
+                          u64 chunk_offset, u64 start, u64 num_bytes);
+int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw,
+                   u64 logical, u64 *length,
+                   struct btrfs_multi_bio **multi_ret, int mirror_num);
+int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
+                    u64 chunk_start, u64 physical, u64 devid,
+                    u64 **logical, int *naddrs, int *stripe_len);
 int btrfs_read_sys_array(struct btrfs_root *root);
 int btrfs_read_chunk_tree(struct btrfs_root *root);
 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
-                     struct btrfs_root *extent_root, u64 *start,
-                     u64 *num_bytes, u32 type);
+                     struct btrfs_root *extent_root, u64 type);
 void btrfs_mapping_init(struct btrfs_mapping_tree *tree);
 void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree);
-int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio);
+int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
+                 int mirror_num, int async_submit);
+int btrfs_read_super_device(struct btrfs_root *root, struct extent_buffer *buf);
+int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
+                      fmode_t flags, void *holder);
+int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder,
+                         struct btrfs_fs_devices **fs_devices_ret);
+int btrfs_close_devices(struct btrfs_fs_devices *fs_devices);
+int btrfs_close_extra_devices(struct btrfs_fs_devices *fs_devices);
+int btrfs_add_device(struct btrfs_trans_handle *trans,
+                    struct btrfs_root *root,
+                    struct btrfs_device *device);
+int btrfs_rm_device(struct btrfs_root *root, char *device_path);
+int btrfs_cleanup_fs_uuids(void);
+int btrfs_num_copies(struct btrfs_mapping_tree *map_tree, u64 logical, u64 len);
+int btrfs_unplug_page(struct btrfs_mapping_tree *map_tree,
+                     u64 logical, struct page *page);
+int btrfs_grow_device(struct btrfs_trans_handle *trans,
+                     struct btrfs_device *device, u64 new_size);
+struct btrfs_device *btrfs_find_device(struct btrfs_root *root, u64 devid,
+                                      u8 *uuid, u8 *fsid);
+int btrfs_shrink_device(struct btrfs_device *device, u64 new_size);
+int btrfs_init_new_device(struct btrfs_root *root, char *path);
+int btrfs_balance(struct btrfs_root *dev_root);
+void btrfs_unlock_volumes(void);
+void btrfs_lock_volumes(void);
+int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset);
 #endif