/*
 * Copyright (C) 2007 Oracle.  All rights reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public
 * License v2 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public
 * License along with this program; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 021110-1307, USA.
 */

#ifndef __BTRFS_VOLUMES_
#define __BTRFS_VOLUMES_

#include <linux/bio.h>
#include <linux/sort.h>
#include <linux/btrfs.h>
#include "async-thread.h"

extern struct mutex uuid_mutex;

#define BTRFS_STRIPE_LEN        SZ_64K

struct buffer_head;
struct btrfs_pending_bios {
        struct bio *head;
        struct bio *tail;
};

/*
 * Use sequence counter to get consistent device stat data on
 * 32-bit processors.
 */
#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
#include <linux/seqlock.h>
#define __BTRFS_NEED_DEVICE_DATA_ORDERED
#define btrfs_device_data_ordered_init(device)  \
        seqcount_init(&device->data_seqcount)
#else
#define btrfs_device_data_ordered_init(device) do { } while (0)
#endif

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 rcu_string *name;

        u64 generation;

        spinlock_t io_lock ____cacheline_aligned;
        int running_pending;
        /* regular prio bios */
        struct btrfs_pending_bios pending_bios;
        /* WRITE_SYNC bios */
        struct btrfs_pending_bios pending_sync_bios;

        struct block_device *bdev;

        /* the mode sent to blkdev_get */
        fmode_t mode;

        int writeable;
        int in_fs_metadata;
        int missing;
        int can_discard;
        int is_tgtdev_for_dev_replace;

#ifdef __BTRFS_NEED_DEVICE_DATA_ORDERED
        seqcount_t data_seqcount;
#endif

        /* the internal btrfs device id */
        u64 devid;

        /* size of the device in memory */
        u64 total_bytes;

        /* size of the device on disk */
        u64 disk_total_bytes;

        /* bytes used */
        u64 bytes_used;

        /* optimal io alignment for this device */
        u32 io_align;

        /* optimal io width for this device */
        u32 io_width;
        /* type and info about this device */
        u64 type;

        /* minimal io size for this device */
        u32 sector_size;

        /* physical drive uuid (or lvm uuid) */
        u8 uuid[BTRFS_UUID_SIZE];

        /*
         * size of the device on the current transaction
         *
         * This variant is update when committing the transaction,
         * and protected by device_list_mutex
         */
        u64 commit_total_bytes;

        /* bytes used on the current transaction */
        u64 commit_bytes_used;
        /*
         * used to manage the device which is resized
         *
         * It is protected by chunk_lock.
         */
        struct list_head resized_list;

        /* for sending down flush barriers */
        int nobarriers;
        struct bio *flush_bio;
        struct completion flush_wait;

        /* per-device scrub information */
        struct scrub_ctx *scrub_device;

        struct btrfs_work work;
        struct rcu_head rcu;
        struct work_struct rcu_work;

        /* readahead state */
        spinlock_t reada_lock;
        atomic_t reada_in_flight;
        u64 reada_next;
        struct reada_zone *reada_curr_zone;
        struct radix_tree_root reada_zones;
        struct radix_tree_root reada_extents;

        /* disk I/O failure stats. For detailed description refer to
         * enum btrfs_dev_stat_values in ioctl.h */
        int dev_stats_valid;

        /* Counter to record the change of device stats */
        atomic_t dev_stats_ccnt;
        atomic_t dev_stat_values[BTRFS_DEV_STAT_VALUES_MAX];
};

/*
 * If we read those variants at the context of their own lock, we needn't
 * use the following helpers, reading them directly is safe.
 */
#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
#define BTRFS_DEVICE_GETSET_FUNCS(name)                                 \
static inline u64                                                       \
btrfs_device_get_##name(const struct btrfs_device *dev)                 \
{                                                                       \
        u64 size;                                                       \
        unsigned int seq;                                               \
                                                                        \
        do {                                                            \
                seq = read_seqcount_begin(&dev->data_seqcount);         \
                size = dev->name;                                       \
        } while (read_seqcount_retry(&dev->data_seqcount, seq));        \
        return size;                                                    \
}                                                                       \
                                                                        \
static inline void                                                      \
btrfs_device_set_##name(struct btrfs_device *dev, u64 size)             \
{                                                                       \
        preempt_disable();                                              \
        write_seqcount_begin(&dev->data_seqcount);                      \
        dev->name = size;                                               \
        write_seqcount_end(&dev->data_seqcount);                        \
        preempt_enable();                                               \
}
#elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT)
#define BTRFS_DEVICE_GETSET_FUNCS(name)                                 \
static inline u64                                                       \
btrfs_device_get_##name(const struct btrfs_device *dev)                 \
{                                                                       \
        u64 size;                                                       \
                                                                        \
        preempt_disable();                                              \
        size = dev->name;                                               \
        preempt_enable();                                               \
        return size;                                                    \
}                                                                       \
                                                                        \
static inline void                                                      \
btrfs_device_set_##name(struct btrfs_device *dev, u64 size)             \
{                                                                       \
        preempt_disable();                                              \
        dev->name = size;                                               \
        preempt_enable();                                               \
}
#else
#define BTRFS_DEVICE_GETSET_FUNCS(name)                                 \
static inline u64                                                       \
btrfs_device_get_##name(const struct btrfs_device *dev)                 \
{                                                                       \
        return dev->name;                                               \
}                                                                       \
                                                                        \
static inline void                                                      \
btrfs_device_set_##name(struct btrfs_device *dev, u64 size)             \
{                                                                       \
        dev->name = size;                                               \
}
#endif

BTRFS_DEVICE_GETSET_FUNCS(total_bytes);
BTRFS_DEVICE_GETSET_FUNCS(disk_total_bytes);
BTRFS_DEVICE_GETSET_FUNCS(bytes_used);

struct btrfs_fs_devices {
        u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */

        u64 num_devices;
        u64 open_devices;
        u64 rw_devices;
        u64 missing_devices;
        u64 total_rw_bytes;
        u64 total_devices;
        struct block_device *latest_bdev;

        /* all of the devices in the FS, protected by a mutex
         * so we can safely walk it to write out the supers without
         * worrying about add/remove by the multi-device code.
         * Scrubbing super can kick off supers writing by holding
         * this mutex lock.
         */
        struct mutex device_list_mutex;
        struct list_head devices;

        struct list_head resized_devices;
        /* devices not currently being allocated */
        struct list_head alloc_list;
        struct list_head list;

        struct btrfs_fs_devices *seed;
        int seeding;

        int opened;

        /* set when we find or add a device that doesn't have the
         * nonrot flag set
         */
        int rotating;

        struct btrfs_fs_info *fs_info;
        /* sysfs kobjects */
        struct kobject fsid_kobj;
        struct kobject *device_dir_kobj;
        struct completion kobj_unregister;
};

#define BTRFS_BIO_INLINE_CSUM_SIZE      64

/*
 * we need the mirror number and stripe index to be passed around
 * the call chain while we are processing end_io (especially errors).
 * Really, what we need is a btrfs_bio structure that has this info
 * and is properly sized with its stripe array, but we're not there
 * quite yet.  We have our own btrfs bioset, and all of the bios
 * we allocate are actually btrfs_io_bios.  We'll cram as much of
 * struct btrfs_bio as we can into this over time.
 */
typedef void (btrfs_io_bio_end_io_t) (struct btrfs_io_bio *bio, int err);
struct btrfs_io_bio {
        unsigned int mirror_num;
        unsigned int stripe_index;
        u64 logical;
        u8 *csum;
        u8 csum_inline[BTRFS_BIO_INLINE_CSUM_SIZE];
        u8 *csum_allocated;
        btrfs_io_bio_end_io_t *end_io;
        struct bio bio;
};

static inline struct btrfs_io_bio *btrfs_io_bio(struct bio *bio)
{
        return container_of(bio, struct btrfs_io_bio, bio);
}

struct btrfs_bio_stripe {
        struct btrfs_device *dev;
        u64 physical;
        u64 length; /* only used for discard mappings */
};

struct btrfs_bio;
typedef void (btrfs_bio_end_io_t) (struct btrfs_bio *bio, int err);

struct btrfs_bio {
        atomic_t refs;
        atomic_t stripes_pending;
        struct btrfs_fs_info *fs_info;
        u64 map_type; /* get from map_lookup->type */
        bio_end_io_t *end_io;
        struct bio *orig_bio;
        unsigned long flags;
        void *private;
        atomic_t error;
        int max_errors;
        int num_stripes;
        int mirror_num;
        int num_tgtdevs;
        int *tgtdev_map;
        /*
         * logical block numbers for the start of each stripe
         * The last one or two are p/q.  These are sorted,
         * so raid_map[0] is the start of our full stripe
         */
        u64 *raid_map;
        struct btrfs_bio_stripe stripes[];
};

struct btrfs_device_info {
        struct btrfs_device *dev;
        u64 dev_offset;
        u64 max_avail;
        u64 total_avail;
};

struct btrfs_raid_attr {
        int sub_stripes;        /* sub_stripes info for map */
        int dev_stripes;        /* stripes per dev */
        int devs_max;           /* max devs to use */
        int devs_min;           /* min devs needed */
        int tolerated_failures; /* max tolerated fail devs */
        int devs_increment;     /* ndevs has to be a multiple of this */
        int ncopies;            /* how many copies to data has */
};

extern const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES];

extern const u64 btrfs_raid_group[BTRFS_NR_RAID_TYPES];

struct map_lookup {
        u64 type;
        int io_align;
        int io_width;
        int stripe_len;
        int sector_size;
        int num_stripes;
        int sub_stripes;
        struct btrfs_bio_stripe stripes[];
};

#define map_lookup_size(n) (sizeof(struct map_lookup) + \
                            (sizeof(struct btrfs_bio_stripe) * (n)))

/*
 * Restriper's general type filter
 */
#define BTRFS_BALANCE_DATA              (1ULL << 0)
#define BTRFS_BALANCE_SYSTEM            (1ULL << 1)
#define BTRFS_BALANCE_METADATA          (1ULL << 2)

#define BTRFS_BALANCE_TYPE_MASK         (BTRFS_BALANCE_DATA |       \
                                         BTRFS_BALANCE_SYSTEM |     \
                                         BTRFS_BALANCE_METADATA)

#define BTRFS_BALANCE_FORCE             (1ULL << 3)
#define BTRFS_BALANCE_RESUME            (1ULL << 4)

/*
 * Balance filters
 */
#define BTRFS_BALANCE_ARGS_PROFILES     (1ULL << 0)
#define BTRFS_BALANCE_ARGS_USAGE        (1ULL << 1)
#define BTRFS_BALANCE_ARGS_DEVID        (1ULL << 2)
#define BTRFS_BALANCE_ARGS_DRANGE       (1ULL << 3)
#define BTRFS_BALANCE_ARGS_VRANGE       (1ULL << 4)
#define BTRFS_BALANCE_ARGS_LIMIT        (1ULL << 5)
#define BTRFS_BALANCE_ARGS_LIMIT_RANGE  (1ULL << 6)
#define BTRFS_BALANCE_ARGS_STRIPES_RANGE (1ULL << 7)
#define BTRFS_BALANCE_ARGS_USAGE_RANGE  (1ULL << 10)

#define BTRFS_BALANCE_ARGS_MASK                 \
        (BTRFS_BALANCE_ARGS_PROFILES |          \
         BTRFS_BALANCE_ARGS_USAGE |             \
         BTRFS_BALANCE_ARGS_DEVID |             \
         BTRFS_BALANCE_ARGS_DRANGE |            \
         BTRFS_BALANCE_ARGS_VRANGE |            \
         BTRFS_BALANCE_ARGS_LIMIT |             \
         BTRFS_BALANCE_ARGS_LIMIT_RANGE |       \
         BTRFS_BALANCE_ARGS_STRIPES_RANGE |     \
         BTRFS_BALANCE_ARGS_USAGE_RANGE)

/*
 * Profile changing flags.  When SOFT is set we won't relocate chunk if
 * it already has the target profile (even though it may be
 * half-filled).
 */
#define BTRFS_BALANCE_ARGS_CONVERT      (1ULL << 8)
#define BTRFS_BALANCE_ARGS_SOFT         (1ULL << 9)

struct btrfs_balance_args;
struct btrfs_balance_progress;
struct btrfs_balance_control {
        struct btrfs_fs_info *fs_info;

        struct btrfs_balance_args data;
        struct btrfs_balance_args meta;
        struct btrfs_balance_args sys;

        u64 flags;

        struct btrfs_balance_progress stat;
};

int btrfs_account_dev_extents_size(struct btrfs_device *device, u64 start,
                                   u64 end, u64 *length);
void btrfs_get_bbio(struct btrfs_bio *bbio);
void btrfs_put_bbio(struct btrfs_bio *bbio);
int btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
                    u64 logical, u64 *length,
                    struct btrfs_bio **bbio_ret, int mirror_num);
int btrfs_map_sblock(struct btrfs_fs_info *fs_info, int rw,
                     u64 logical, u64 *length,
                     struct btrfs_bio **bbio_ret, int mirror_num,
                     int need_raid_map);
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 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 mirror_num, int async_submit);
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);
void btrfs_close_extra_devices(struct btrfs_fs_devices *fs_devices, int step);
int btrfs_find_device_missing_or_by_path(struct btrfs_root *root,
                                         char *device_path,
                                         struct btrfs_device **device);
struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
                                        const u64 *devid,
                                        const u8 *uuid);
int btrfs_rm_device(struct btrfs_root *root, char *device_path);
void btrfs_cleanup_fs_uuids(void);
int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len);
int btrfs_grow_device(struct btrfs_trans_handle *trans,
                      struct btrfs_device *device, u64 new_size);
struct btrfs_device *btrfs_find_device(struct btrfs_fs_info *fs_info, 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_init_dev_replace_tgtdev(struct btrfs_root *root, char *device_path,
                                  struct btrfs_device *srcdev,
                                  struct btrfs_device **device_out);
int btrfs_balance(struct btrfs_balance_control *bctl,
                  struct btrfs_ioctl_balance_args *bargs);
int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info);
int btrfs_recover_balance(struct btrfs_fs_info *fs_info);
int btrfs_pause_balance(struct btrfs_fs_info *fs_info);
int btrfs_cancel_balance(struct btrfs_fs_info *fs_info);
int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info);
int btrfs_check_uuid_tree(struct btrfs_fs_info *fs_info);
int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset);
int find_free_dev_extent_start(struct btrfs_transaction *transaction,
                         struct btrfs_device *device, u64 num_bytes,
                         u64 search_start, u64 *start, u64 *max_avail);
int find_free_dev_extent(struct btrfs_trans_handle *trans,
                         struct btrfs_device *device, u64 num_bytes,
                         u64 *start, u64 *max_avail);
void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index);
int btrfs_get_dev_stats(struct btrfs_root *root,
                        struct btrfs_ioctl_get_dev_stats *stats);
void btrfs_init_devices_late(struct btrfs_fs_info *fs_info);
int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info);
int btrfs_run_dev_stats(struct btrfs_trans_handle *trans,
                        struct btrfs_fs_info *fs_info);
void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_fs_info *fs_info,
                                        struct btrfs_device *srcdev);
void btrfs_rm_dev_replace_free_srcdev(struct btrfs_fs_info *fs_info,
                                      struct btrfs_device *srcdev);
void btrfs_destroy_dev_replace_tgtdev(struct btrfs_fs_info *fs_info,
                                      struct btrfs_device *tgtdev);
void btrfs_init_dev_replace_tgtdev_for_resume(struct btrfs_fs_info *fs_info,
                                              struct btrfs_device *tgtdev);
void btrfs_scratch_superblocks(struct block_device *bdev, char *device_path);
int btrfs_is_parity_mirror(struct btrfs_mapping_tree *map_tree,
                           u64 logical, u64 len, int mirror_num);
unsigned long btrfs_full_stripe_len(struct btrfs_root *root,
                                    struct btrfs_mapping_tree *map_tree,
                                    u64 logical);
int btrfs_finish_chunk_alloc(struct btrfs_trans_handle *trans,
                                struct btrfs_root *extent_root,
                                u64 chunk_offset, u64 chunk_size);
int btrfs_remove_chunk(struct btrfs_trans_handle *trans,
                       struct btrfs_root *root, u64 chunk_offset);

static inline int btrfs_dev_stats_dirty(struct btrfs_device *dev)
{
        return atomic_read(&dev->dev_stats_ccnt);
}

static inline void btrfs_dev_stat_inc(struct btrfs_device *dev,
                                      int index)
{
        atomic_inc(dev->dev_stat_values + index);
        smp_mb__before_atomic();
        atomic_inc(&dev->dev_stats_ccnt);
}

static inline int btrfs_dev_stat_read(struct btrfs_device *dev,
                                      int index)
{
        return atomic_read(dev->dev_stat_values + index);
}

static inline int btrfs_dev_stat_read_and_reset(struct btrfs_device *dev,
                                                int index)
{
        int ret;

        ret = atomic_xchg(dev->dev_stat_values + index, 0);
        smp_mb__before_atomic();
        atomic_inc(&dev->dev_stats_ccnt);
        return ret;
}

static inline void btrfs_dev_stat_set(struct btrfs_device *dev,
                                      int index, unsigned long val)
{
        atomic_set(dev->dev_stat_values + index, val);
        smp_mb__before_atomic();
        atomic_inc(&dev->dev_stats_ccnt);
}

static inline void btrfs_dev_stat_reset(struct btrfs_device *dev,
                                        int index)
{
        btrfs_dev_stat_set(dev, index, 0);
}

void btrfs_update_commit_device_size(struct btrfs_fs_info *fs_info);
void btrfs_update_commit_device_bytes_used(struct btrfs_root *root,
                                        struct btrfs_transaction *transaction);

static inline void lock_chunks(struct btrfs_root *root)
{
        mutex_lock(&root->fs_info->chunk_mutex);
}

static inline void unlock_chunks(struct btrfs_root *root)
{
        mutex_unlock(&root->fs_info->chunk_mutex);
}

struct list_head *btrfs_get_fs_uuids(void);
void btrfs_set_fs_info_ptr(struct btrfs_fs_info *fs_info);
void btrfs_reset_fs_info_ptr(struct btrfs_fs_info *fs_info);

#endif