/*
 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
 * 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 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it would 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 the Free Software Foundation,
 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
#ifndef __XFS_MOUNT_H__
#define __XFS_MOUNT_H__

struct xlog;
struct xfs_inode;
struct xfs_mru_cache;
struct xfs_nameops;
struct xfs_ail;
struct xfs_quotainfo;
struct xfs_dir_ops;
struct xfs_da_geometry;

/* dynamic preallocation free space thresholds, 5% down to 1% */
enum {
        XFS_LOWSP_1_PCNT = 0,
        XFS_LOWSP_2_PCNT,
        XFS_LOWSP_3_PCNT,
        XFS_LOWSP_4_PCNT,
        XFS_LOWSP_5_PCNT,
        XFS_LOWSP_MAX,
};

/*
 * Error Configuration
 *
 * Error classes define the subsystem the configuration belongs to.
 * Error numbers define the errors that are configurable.
 */
enum {
        XFS_ERR_METADATA,
        XFS_ERR_CLASS_MAX,
};
enum {
        XFS_ERR_DEFAULT,
        XFS_ERR_EIO,
        XFS_ERR_ENOSPC,
        XFS_ERR_ENODEV,
        XFS_ERR_ERRNO_MAX,
};

#define XFS_ERR_RETRY_FOREVER   -1

/*
 * Although retry_timeout is in jiffies which is normally an unsigned long,
 * we limit the retry timeout to 86400 seconds, or one day.  So even a
 * signed 32-bit long is sufficient for a HZ value up to 24855.  Making it
 * signed lets us store the special "-1" value, meaning retry forever.
 */
struct xfs_error_cfg {
        struct xfs_kobj kobj;
        int             max_retries;
        long            retry_timeout;  /* in jiffies, -1 = infinite */
};

typedef struct xfs_mount {
        struct super_block      *m_super;
        xfs_tid_t               m_tid;          /* next unused tid for fs */
        struct xfs_ail          *m_ail;         /* fs active log item list */

        struct xfs_sb           m_sb;           /* copy of fs superblock */
        spinlock_t              m_sb_lock;      /* sb counter lock */
        struct percpu_counter   m_icount;       /* allocated inodes counter */
        struct percpu_counter   m_ifree;        /* free inodes counter */
        struct percpu_counter   m_fdblocks;     /* free block counter */

        struct xfs_buf          *m_sb_bp;       /* buffer for superblock */
        char                    *m_fsname;      /* filesystem name */
        int                     m_fsname_len;   /* strlen of fs name */
        char                    *m_rtname;      /* realtime device name */
        char                    *m_logname;     /* external log device name */
        int                     m_bsize;        /* fs logical block size */
        xfs_agnumber_t          m_agfrotor;     /* last ag where space found */
        xfs_agnumber_t          m_agirotor;     /* last ag dir inode alloced */
        spinlock_t              m_agirotor_lock;/* .. and lock protecting it */
        xfs_agnumber_t          m_maxagi;       /* highest inode alloc group */
        uint                    m_readio_log;   /* min read size log bytes */
        uint                    m_readio_blocks; /* min read size blocks */
        uint                    m_writeio_log;  /* min write size log bytes */
        uint                    m_writeio_blocks; /* min write size blocks */
        struct xfs_da_geometry  *m_dir_geo;     /* directory block geometry */
        struct xfs_da_geometry  *m_attr_geo;    /* attribute block geometry */
        struct xlog             *m_log;         /* log specific stuff */
        int                     m_logbufs;      /* number of log buffers */
        int                     m_logbsize;     /* size of each log buffer */
        uint                    m_rsumlevels;   /* rt summary levels */
        uint                    m_rsumsize;     /* size of rt summary, bytes */
        struct xfs_inode        *m_rbmip;       /* pointer to bitmap inode */
        struct xfs_inode        *m_rsumip;      /* pointer to summary inode */
        struct xfs_inode        *m_rootip;      /* pointer to root directory */
        struct xfs_quotainfo    *m_quotainfo;   /* disk quota information */
        xfs_buftarg_t           *m_ddev_targp;  /* saves taking the address */
        xfs_buftarg_t           *m_logdev_targp;/* ptr to log device */
        xfs_buftarg_t           *m_rtdev_targp; /* ptr to rt device */
        __uint8_t               m_blkbit_log;   /* blocklog + NBBY */
        __uint8_t               m_blkbb_log;    /* blocklog - BBSHIFT */
        __uint8_t               m_agno_log;     /* log #ag's */
        __uint8_t               m_agino_log;    /* #bits for agino in inum */
        uint                    m_inode_cluster_size;/* min inode buf size */
        uint                    m_blockmask;    /* sb_blocksize-1 */
        uint                    m_blockwsize;   /* sb_blocksize in words */
        uint                    m_blockwmask;   /* blockwsize-1 */
        uint                    m_alloc_mxr[2]; /* max alloc btree records */
        uint                    m_alloc_mnr[2]; /* min alloc btree records */
        uint                    m_bmap_dmxr[2]; /* max bmap btree records */
        uint                    m_bmap_dmnr[2]; /* min bmap btree records */
        uint                    m_inobt_mxr[2]; /* max inobt btree records */
        uint                    m_inobt_mnr[2]; /* min inobt btree records */
        uint                    m_rmap_mxr[2];  /* max rmap btree records */
        uint                    m_rmap_mnr[2];  /* min rmap btree records */
        uint                    m_refc_mxr[2];  /* max refc btree records */
        uint                    m_refc_mnr[2];  /* min refc btree records */
        uint                    m_ag_maxlevels; /* XFS_AG_MAXLEVELS */
        uint                    m_bm_maxlevels[2]; /* XFS_BM_MAXLEVELS */
        uint                    m_in_maxlevels; /* max inobt btree levels. */
        uint                    m_rmap_maxlevels; /* max rmap btree levels */
        uint                    m_refc_maxlevels; /* max refcount btree level */
        xfs_extlen_t            m_ag_prealloc_blocks; /* reserved ag blocks */
        uint                    m_alloc_set_aside; /* space we can't use */
        uint                    m_ag_max_usable; /* max space per AG */
        struct radix_tree_root  m_perag_tree;   /* per-ag accounting info */
        spinlock_t              m_perag_lock;   /* lock for m_perag_tree */
        struct mutex            m_growlock;     /* growfs mutex */
        int                     m_fixedfsid[2]; /* unchanged for life of FS */
        uint                    m_dmevmask;     /* DMI events for this FS */
        __uint64_t              m_flags;        /* global mount flags */
        int                     m_ialloc_inos;  /* inodes in inode allocation */
        int                     m_ialloc_blks;  /* blocks in inode allocation */
        int                     m_ialloc_min_blks;/* min blocks in sparse inode
                                                   * allocation */
        int                     m_inoalign_mask;/* mask sb_inoalignmt if used */
        uint                    m_qflags;       /* quota status flags */
        struct xfs_trans_resv   m_resv;         /* precomputed res values */
        __uint64_t              m_maxicount;    /* maximum inode count */
        __uint64_t              m_resblks;      /* total reserved blocks */
        __uint64_t              m_resblks_avail;/* available reserved blocks */
        __uint64_t              m_resblks_save; /* reserved blks @ remount,ro */
        int                     m_dalign;       /* stripe unit */
        int                     m_swidth;       /* stripe width */
        int                     m_sinoalign;    /* stripe unit inode alignment */
        __uint8_t               m_sectbb_log;   /* sectlog - BBSHIFT */
        const struct xfs_nameops *m_dirnameops; /* vector of dir name ops */
        const struct xfs_dir_ops *m_dir_inode_ops; /* vector of dir inode ops */
        const struct xfs_dir_ops *m_nondir_inode_ops; /* !dir inode ops */
        uint                    m_chsize;       /* size of next field */
        atomic_t                m_active_trans; /* number trans frozen */
        struct xfs_mru_cache    *m_filestream;  /* per-mount filestream data */
        struct delayed_work     m_reclaim_work; /* background inode reclaim */
        struct delayed_work     m_eofblocks_work; /* background eof blocks
                                                     trimming */
        struct delayed_work     m_cowblocks_work; /* background cow blocks
                                                     trimming */
        bool                    m_update_sb;    /* sb needs update in mount */
        int64_t                 m_low_space[XFS_LOWSP_MAX];
                                                /* low free space thresholds */
        struct xfs_kobj         m_kobj;
        struct xfs_kobj         m_error_kobj;
        struct xfs_kobj         m_error_meta_kobj;
        struct xfs_error_cfg    m_error_cfg[XFS_ERR_CLASS_MAX][XFS_ERR_ERRNO_MAX];
        struct xstats           m_stats;        /* per-fs stats */

        struct workqueue_struct *m_buf_workqueue;
        struct workqueue_struct *m_data_workqueue;
        struct workqueue_struct *m_unwritten_workqueue;
        struct workqueue_struct *m_cil_workqueue;
        struct workqueue_struct *m_reclaim_workqueue;
        struct workqueue_struct *m_log_workqueue;
        struct workqueue_struct *m_eofblocks_workqueue;

        /*
         * Generation of the filesysyem layout.  This is incremented by each
         * growfs, and used by the pNFS server to ensure the client updates
         * its view of the block device once it gets a layout that might
         * reference the newly added blocks.  Does not need to be persistent
         * as long as we only allow file system size increments, but if we
         * ever support shrinks it would have to be persisted in addition
         * to various other kinds of pain inflicted on the pNFS server.
         */
        __uint32_t              m_generation;

        bool                    m_fail_unmount;
#ifdef DEBUG
        /*
         * DEBUG mode instrumentation to test and/or trigger delayed allocation
         * block killing in the event of failed writes. When enabled, all
         * buffered writes are forced to fail. All delalloc blocks in the range
         * of the write (including pre-existing delalloc blocks!) are tossed as
         * part of the write failure error handling sequence.
         */
        bool                    m_fail_writes;
#endif
} xfs_mount_t;

/*
 * Flags for m_flags.
 */
#define XFS_MOUNT_WSYNC         (1ULL << 0)     /* for nfs - all metadata ops
                                                   must be synchronous except
                                                   for space allocations */
#define XFS_MOUNT_UNMOUNTING    (1ULL << 1)     /* filesystem is unmounting */
#define XFS_MOUNT_WAS_CLEAN     (1ULL << 3)
#define XFS_MOUNT_FS_SHUTDOWN   (1ULL << 4)     /* atomic stop of all filesystem
                                                   operations, typically for
                                                   disk errors in metadata */
#define XFS_MOUNT_DISCARD       (1ULL << 5)     /* discard unused blocks */
#define XFS_MOUNT_NOALIGN       (1ULL << 7)     /* turn off stripe alignment
                                                   allocations */
#define XFS_MOUNT_ATTR2         (1ULL << 8)     /* allow use of attr2 format */
#define XFS_MOUNT_GRPID         (1ULL << 9)     /* group-ID assigned from directory */
#define XFS_MOUNT_NORECOVERY    (1ULL << 10)    /* no recovery - dirty fs */
#define XFS_MOUNT_DFLT_IOSIZE   (1ULL << 12)    /* set default i/o size */
#define XFS_MOUNT_SMALL_INUMS   (1ULL << 14)    /* user wants 32bit inodes */
#define XFS_MOUNT_32BITINODES   (1ULL << 15)    /* inode32 allocator active */
#define XFS_MOUNT_NOUUID        (1ULL << 16)    /* ignore uuid during mount */
#define XFS_MOUNT_BARRIER       (1ULL << 17)
#define XFS_MOUNT_IKEEP         (1ULL << 18)    /* keep empty inode clusters*/
#define XFS_MOUNT_SWALLOC       (1ULL << 19)    /* turn on stripe width
                                                 * allocation */
#define XFS_MOUNT_RDONLY        (1ULL << 20)    /* read-only fs */
#define XFS_MOUNT_DIRSYNC       (1ULL << 21)    /* synchronous directory ops */
#define XFS_MOUNT_COMPAT_IOSIZE (1ULL << 22)    /* don't report large preferred
                                                 * I/O size in stat() */
#define XFS_MOUNT_FILESTREAMS   (1ULL << 24)    /* enable the filestreams
                                                   allocator */
#define XFS_MOUNT_NOATTR2       (1ULL << 25)    /* disable use of attr2 format */

#define XFS_MOUNT_DAX           (1ULL << 62)    /* TEST ONLY! */


/*
 * Default minimum read and write sizes.
 */
#define XFS_READIO_LOG_LARGE    16
#define XFS_WRITEIO_LOG_LARGE   16

/*
 * Max and min values for mount-option defined I/O
 * preallocation sizes.
 */
#define XFS_MAX_IO_LOG          30      /* 1G */
#define XFS_MIN_IO_LOG          PAGE_SHIFT

/*
 * Synchronous read and write sizes.  This should be
 * better for NFSv2 wsync filesystems.
 */
#define XFS_WSYNC_READIO_LOG    15      /* 32k */
#define XFS_WSYNC_WRITEIO_LOG   14      /* 16k */

/*
 * Allow large block sizes to be reported to userspace programs if the
 * "largeio" mount option is used.
 *
 * If compatibility mode is specified, simply return the basic unit of caching
 * so that we don't get inefficient read/modify/write I/O from user apps.
 * Otherwise....
 *
 * If the underlying volume is a stripe, then return the stripe width in bytes
 * as the recommended I/O size. It is not a stripe and we've set a default
 * buffered I/O size, return that, otherwise return the compat default.
 */
static inline unsigned long
xfs_preferred_iosize(xfs_mount_t *mp)
{
        if (mp->m_flags & XFS_MOUNT_COMPAT_IOSIZE)
                return PAGE_SIZE;
        return (mp->m_swidth ?
                (mp->m_swidth << mp->m_sb.sb_blocklog) :
                ((mp->m_flags & XFS_MOUNT_DFLT_IOSIZE) ?
                        (1 << (int)MAX(mp->m_readio_log, mp->m_writeio_log)) :
                        PAGE_SIZE));
}

#define XFS_LAST_UNMOUNT_WAS_CLEAN(mp)  \
                                ((mp)->m_flags & XFS_MOUNT_WAS_CLEAN)
#define XFS_FORCED_SHUTDOWN(mp) ((mp)->m_flags & XFS_MOUNT_FS_SHUTDOWN)
void xfs_do_force_shutdown(struct xfs_mount *mp, int flags, char *fname,
                int lnnum);
#define xfs_force_shutdown(m,f) \
        xfs_do_force_shutdown(m, f, __FILE__, __LINE__)

#define SHUTDOWN_META_IO_ERROR  0x0001  /* write attempt to metadata failed */
#define SHUTDOWN_LOG_IO_ERROR   0x0002  /* write attempt to the log failed */
#define SHUTDOWN_FORCE_UMOUNT   0x0004  /* shutdown from a forced unmount */
#define SHUTDOWN_CORRUPT_INCORE 0x0008  /* corrupt in-memory data structures */
#define SHUTDOWN_REMOTE_REQ     0x0010  /* shutdown came from remote cell */
#define SHUTDOWN_DEVICE_REQ     0x0020  /* failed all paths to the device */

/*
 * Flags for xfs_mountfs
 */
#define XFS_MFSI_QUIET          0x40    /* Be silent if mount errors found */

static inline xfs_agnumber_t
xfs_daddr_to_agno(struct xfs_mount *mp, xfs_daddr_t d)
{
        xfs_daddr_t ld = XFS_BB_TO_FSBT(mp, d);
        do_div(ld, mp->m_sb.sb_agblocks);
        return (xfs_agnumber_t) ld;
}

static inline xfs_agblock_t
xfs_daddr_to_agbno(struct xfs_mount *mp, xfs_daddr_t d)
{
        xfs_daddr_t ld = XFS_BB_TO_FSBT(mp, d);
        return (xfs_agblock_t) do_div(ld, mp->m_sb.sb_agblocks);
}

#ifdef DEBUG
static inline bool
xfs_mp_fail_writes(struct xfs_mount *mp)
{
        return mp->m_fail_writes;
}
#else
static inline bool
xfs_mp_fail_writes(struct xfs_mount *mp)
{
        return 0;
}
#endif

/* per-AG block reservation data structures*/
enum xfs_ag_resv_type {
        XFS_AG_RESV_NONE = 0,
        XFS_AG_RESV_METADATA,
        XFS_AG_RESV_AGFL,
};

struct xfs_ag_resv {
        /* number of blocks originally reserved here */
        xfs_extlen_t                    ar_orig_reserved;
        /* number of blocks reserved here */
        xfs_extlen_t                    ar_reserved;
        /* number of blocks originally asked for */
        xfs_extlen_t                    ar_asked;
};

/*
 * Per-ag incore structure, copies of information in agf and agi, to improve the
 * performance of allocation group selection.
 */
typedef struct xfs_perag {
        struct xfs_mount *pag_mount;    /* owner filesystem */
        xfs_agnumber_t  pag_agno;       /* AG this structure belongs to */
        atomic_t        pag_ref;        /* perag reference count */
        char            pagf_init;      /* this agf's entry is initialized */
        char            pagi_init;      /* this agi's entry is initialized */
        char            pagf_metadata;  /* the agf is preferred to be metadata */
        char            pagi_inodeok;   /* The agi is ok for inodes */
        __uint8_t       pagf_levels[XFS_BTNUM_AGF];
                                        /* # of levels in bno & cnt btree */
        __uint32_t      pagf_flcount;   /* count of blocks in freelist */
        xfs_extlen_t    pagf_freeblks;  /* total free blocks */
        xfs_extlen_t    pagf_longest;   /* longest free space */
        __uint32_t      pagf_btreeblks; /* # of blocks held in AGF btrees */
        xfs_agino_t     pagi_freecount; /* number of free inodes */
        xfs_agino_t     pagi_count;     /* number of allocated inodes */

        /*
         * Inode allocation search lookup optimisation.
         * If the pagino matches, the search for new inodes
         * doesn't need to search the near ones again straight away
         */
        xfs_agino_t     pagl_pagino;
        xfs_agino_t     pagl_leftrec;
        xfs_agino_t     pagl_rightrec;
        spinlock_t      pagb_lock;      /* lock for pagb_tree */
        struct rb_root  pagb_tree;      /* ordered tree of busy extents */

        atomic_t        pagf_fstrms;    /* # of filestreams active in this AG */

        spinlock_t      pag_ici_lock;   /* incore inode cache lock */
        struct radix_tree_root pag_ici_root;    /* incore inode cache root */
        int             pag_ici_reclaimable;    /* reclaimable inodes */
        struct mutex    pag_ici_reclaim_lock;   /* serialisation point */
        unsigned long   pag_ici_reclaim_cursor; /* reclaim restart point */

        /* buffer cache index */
        spinlock_t      pag_buf_lock;   /* lock for pag_buf_tree */
        struct rb_root  pag_buf_tree;   /* ordered tree of active buffers */

        /* for rcu-safe freeing */
        struct rcu_head rcu_head;
        int             pagb_count;     /* pagb slots in use */

        /* Blocks reserved for all kinds of metadata. */
        struct xfs_ag_resv      pag_meta_resv;
        /* Blocks reserved for just AGFL-based metadata. */
        struct xfs_ag_resv      pag_agfl_resv;

        /* reference count */
        __uint8_t               pagf_refcount_level;
} xfs_perag_t;

static inline struct xfs_ag_resv *
xfs_perag_resv(
        struct xfs_perag        *pag,
        enum xfs_ag_resv_type   type)
{
        switch (type) {
        case XFS_AG_RESV_METADATA:
                return &pag->pag_meta_resv;
        case XFS_AG_RESV_AGFL:
                return &pag->pag_agfl_resv;
        default:
                return NULL;
        }
}

extern void     xfs_uuid_table_free(void);
extern int      xfs_log_sbcount(xfs_mount_t *);
extern __uint64_t xfs_default_resblks(xfs_mount_t *mp);
extern int      xfs_mountfs(xfs_mount_t *mp);
extern int      xfs_initialize_perag(xfs_mount_t *mp, xfs_agnumber_t agcount,
                                     xfs_agnumber_t *maxagi);
extern void     xfs_unmountfs(xfs_mount_t *);

extern int      xfs_mod_icount(struct xfs_mount *mp, int64_t delta);
extern int      xfs_mod_ifree(struct xfs_mount *mp, int64_t delta);
extern int      xfs_mod_fdblocks(struct xfs_mount *mp, int64_t delta,
                                 bool reserved);
extern int      xfs_mod_frextents(struct xfs_mount *mp, int64_t delta);

extern struct xfs_buf *xfs_getsb(xfs_mount_t *, int);
extern int      xfs_readsb(xfs_mount_t *, int);
extern void     xfs_freesb(xfs_mount_t *);
extern bool     xfs_fs_writable(struct xfs_mount *mp, int level);
extern int      xfs_sb_validate_fsb_count(struct xfs_sb *, __uint64_t);

extern int      xfs_dev_is_read_only(struct xfs_mount *, char *);

extern void     xfs_set_low_space_thresholds(struct xfs_mount *);

int     xfs_zero_extent(struct xfs_inode *ip, xfs_fsblock_t start_fsb,
                        xfs_off_t count_fsb);

struct xfs_error_cfg * xfs_error_get_cfg(struct xfs_mount *mp,
                int error_class, int error);

#endif  /* __XFS_MOUNT_H__ */