/* * Copyright (c) 2000-2004 Silicon Graphics, Inc. All Rights Reserved. * * This program is free software; you can redistribute it and/or modify it * under the terms of version 2 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. * * Further, this software is distributed without any warranty that it is * free of the rightful claim of any third person regarding infringement * or the like. Any license provided herein, whether implied or * otherwise, applies only to this software file. Patent licenses, if * any, provided herein do not apply to combinations of this program with * other software, or any other product whatsoever. * * You should have received a copy of the GNU General Public License along * with this program; if not, write the Free Software Foundation, Inc., 59 * Temple Place - Suite 330, Boston MA 02111-1307, USA. * * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy, * Mountain View, CA 94043, or: * * http://www.sgi.com * * For further information regarding this notice, see: * * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/ */ /* * Written by Steve Lord, Jim Mostek, Russell Cattelan at SGI */ #ifndef __XFS_BUF_H__ #define __XFS_BUF_H__ #include #include #include #include #include #include #include #include #include /* * Base types */ #define XFS_BUF_DADDR_NULL ((xfs_daddr_t) (-1LL)) #define page_buf_ctob(pp) ((pp) * PAGE_CACHE_SIZE) #define page_buf_btoc(dd) (((dd) + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT) #define page_buf_btoct(dd) ((dd) >> PAGE_CACHE_SHIFT) #define page_buf_poff(aa) ((aa) & ~PAGE_CACHE_MASK) typedef enum page_buf_rw_e { PBRW_READ = 1, /* transfer into target memory */ PBRW_WRITE = 2, /* transfer from target memory */ PBRW_ZERO = 3 /* Zero target memory */ } page_buf_rw_t; typedef enum page_buf_flags_e { /* pb_flags values */ PBF_READ = (1 << 0), /* buffer intended for reading from device */ PBF_WRITE = (1 << 1), /* buffer intended for writing to device */ PBF_MAPPED = (1 << 2), /* buffer mapped (pb_addr valid) */ PBF_PARTIAL = (1 << 3), /* buffer partially read */ PBF_ASYNC = (1 << 4), /* initiator will not wait for completion */ PBF_NONE = (1 << 5), /* buffer not read at all */ PBF_DELWRI = (1 << 6), /* buffer has dirty pages */ PBF_STALE = (1 << 7), /* buffer has been staled, do not find it */ PBF_FS_MANAGED = (1 << 8), /* filesystem controls freeing memory */ PBF_FS_DATAIOD = (1 << 9), /* schedule IO completion on fs datad */ PBF_FORCEIO = (1 << 10), /* ignore any cache state */ PBF_FLUSH = (1 << 11), /* flush disk write cache */ PBF_READ_AHEAD = (1 << 12), /* asynchronous read-ahead */ /* flags used only as arguments to access routines */ PBF_LOCK = (1 << 14), /* lock requested */ PBF_TRYLOCK = (1 << 15), /* lock requested, but do not wait */ PBF_DONT_BLOCK = (1 << 16), /* do not block in current thread */ /* flags used only internally */ _PBF_PAGE_CACHE = (1 << 17),/* backed by pagecache */ _PBF_KMEM_ALLOC = (1 << 18),/* backed by kmem_alloc() */ _PBF_RUN_QUEUES = (1 << 19),/* run block device task queue */ } page_buf_flags_t; #define PBF_UPDATE (PBF_READ | PBF_WRITE) #define PBF_NOT_DONE(pb) (((pb)->pb_flags & (PBF_PARTIAL|PBF_NONE)) != 0) #define PBF_DONE(pb) (((pb)->pb_flags & (PBF_PARTIAL|PBF_NONE)) == 0) typedef struct xfs_bufhash { struct list_head bh_list; spinlock_t bh_lock; } xfs_bufhash_t; typedef struct xfs_buftarg { dev_t pbr_dev; struct block_device *pbr_bdev; struct address_space *pbr_mapping; unsigned int pbr_bsize; unsigned int pbr_sshift; size_t pbr_smask; /* per-device buffer hash table */ uint bt_hashmask; uint bt_hashshift; xfs_bufhash_t *bt_hash; } xfs_buftarg_t; /* * xfs_buf_t: Buffer structure for page cache-based buffers * * This buffer structure is used by the page cache buffer management routines * to refer to an assembly of pages forming a logical buffer. The actual I/O * is performed with buffer_head structures, as required by drivers. * * The buffer structure is used on temporary basis only, and discarded when * released. The real data storage is recorded in the page cache. Metadata is * hashed to the block device on which the file system resides. */ struct xfs_buf; /* call-back function on I/O completion */ typedef void (*page_buf_iodone_t)(struct xfs_buf *); /* call-back function on I/O completion */ typedef void (*page_buf_relse_t)(struct xfs_buf *); /* pre-write function */ typedef int (*page_buf_bdstrat_t)(struct xfs_buf *); #define PB_PAGES 2 typedef struct xfs_buf { struct semaphore pb_sema; /* semaphore for lockables */ unsigned long pb_queuetime; /* time buffer was queued */ atomic_t pb_pin_count; /* pin count */ wait_queue_head_t pb_waiters; /* unpin waiters */ struct list_head pb_list; page_buf_flags_t pb_flags; /* status flags */ struct list_head pb_hash_list; /* hash table list */ xfs_bufhash_t *pb_hash; /* hash table list start */ xfs_buftarg_t *pb_target; /* buffer target (device) */ atomic_t pb_hold; /* reference count */ xfs_daddr_t pb_bn; /* block number for I/O */ loff_t pb_file_offset; /* offset in file */ size_t pb_buffer_length; /* size of buffer in bytes */ size_t pb_count_desired; /* desired transfer size */ void *pb_addr; /* virtual address of buffer */ struct work_struct pb_iodone_work; atomic_t pb_io_remaining;/* #outstanding I/O requests */ page_buf_iodone_t pb_iodone; /* I/O completion function */ page_buf_relse_t pb_relse; /* releasing function */ page_buf_bdstrat_t pb_strat; /* pre-write function */ struct semaphore pb_iodonesema; /* Semaphore for I/O waiters */ void *pb_fspriv; void *pb_fspriv2; void *pb_fspriv3; unsigned short pb_error; /* error code on I/O */ unsigned short pb_locked; /* page array is locked */ unsigned int pb_page_count; /* size of page array */ unsigned int pb_offset; /* page offset in first page */ struct page **pb_pages; /* array of page pointers */ struct page *pb_page_array[PB_PAGES]; /* inline pages */ #ifdef PAGEBUF_LOCK_TRACKING int pb_last_holder; #endif } xfs_buf_t; /* Finding and Reading Buffers */ extern xfs_buf_t *_pagebuf_find( /* find buffer for block if */ /* the block is in memory */ xfs_buftarg_t *, /* inode for block */ loff_t, /* starting offset of range */ size_t, /* length of range */ page_buf_flags_t, /* PBF_LOCK */ xfs_buf_t *); /* newly allocated buffer */ #define xfs_incore(buftarg,blkno,len,lockit) \ _pagebuf_find(buftarg, blkno ,len, lockit, NULL) extern xfs_buf_t *xfs_buf_get_flags( /* allocate a buffer */ xfs_buftarg_t *, /* inode for buffer */ loff_t, /* starting offset of range */ size_t, /* length of range */ page_buf_flags_t); /* PBF_LOCK, PBF_READ, */ /* PBF_ASYNC */ #define xfs_buf_get(target, blkno, len, flags) \ xfs_buf_get_flags((target), (blkno), (len), PBF_LOCK | PBF_MAPPED) extern xfs_buf_t *xfs_buf_read_flags( /* allocate and read a buffer */ xfs_buftarg_t *, /* inode for buffer */ loff_t, /* starting offset of range */ size_t, /* length of range */ page_buf_flags_t); /* PBF_LOCK, PBF_ASYNC */ #define xfs_buf_read(target, blkno, len, flags) \ xfs_buf_read_flags((target), (blkno), (len), PBF_LOCK | PBF_MAPPED) extern xfs_buf_t *pagebuf_lookup( xfs_buftarg_t *, loff_t, /* starting offset of range */ size_t, /* length of range */ page_buf_flags_t); /* PBF_READ, PBF_WRITE, */ /* PBF_FORCEIO, */ extern xfs_buf_t *pagebuf_get_empty( /* allocate pagebuf struct with */ /* no memory or disk address */ size_t len, xfs_buftarg_t *); /* mount point "fake" inode */ extern xfs_buf_t *pagebuf_get_no_daddr(/* allocate pagebuf struct */ /* without disk address */ size_t len, xfs_buftarg_t *); /* mount point "fake" inode */ extern int pagebuf_associate_memory( xfs_buf_t *, void *, size_t); extern void pagebuf_hold( /* increment reference count */ xfs_buf_t *); /* buffer to hold */ extern void pagebuf_readahead( /* read ahead into cache */ xfs_buftarg_t *, /* target for buffer (or NULL) */ loff_t, /* starting offset of range */ size_t, /* length of range */ page_buf_flags_t); /* additional read flags */ /* Releasing Buffers */ extern void pagebuf_free( /* deallocate a buffer */ xfs_buf_t *); /* buffer to deallocate */ extern void pagebuf_rele( /* release hold on a buffer */ xfs_buf_t *); /* buffer to release */ /* Locking and Unlocking Buffers */ extern int pagebuf_cond_lock( /* lock buffer, if not locked */ /* (returns -EBUSY if locked) */ xfs_buf_t *); /* buffer to lock */ extern int pagebuf_lock_value( /* return count on lock */ xfs_buf_t *); /* buffer to check */ extern int pagebuf_lock( /* lock buffer */ xfs_buf_t *); /* buffer to lock */ extern void pagebuf_unlock( /* unlock buffer */ xfs_buf_t *); /* buffer to unlock */ /* Buffer Read and Write Routines */ extern void pagebuf_iodone( /* mark buffer I/O complete */ xfs_buf_t *, /* buffer to mark */ int, /* use data/log helper thread. */ int); /* run completion locally, or in * a helper thread. */ extern void pagebuf_ioerror( /* mark buffer in error (or not) */ xfs_buf_t *, /* buffer to mark */ int); /* error to store (0 if none) */ extern int pagebuf_iostart( /* start I/O on a buffer */ xfs_buf_t *, /* buffer to start */ page_buf_flags_t); /* PBF_LOCK, PBF_ASYNC, */ /* PBF_READ, PBF_WRITE, */ /* PBF_DELWRI */ extern int pagebuf_iorequest( /* start real I/O */ xfs_buf_t *); /* buffer to convey to device */ extern int pagebuf_iowait( /* wait for buffer I/O done */ xfs_buf_t *); /* buffer to wait on */ extern void pagebuf_iomove( /* move data in/out of pagebuf */ xfs_buf_t *, /* buffer to manipulate */ size_t, /* starting buffer offset */ size_t, /* length in buffer */ caddr_t, /* data pointer */ page_buf_rw_t); /* direction */ static inline int pagebuf_iostrategy(xfs_buf_t *pb) { return pb->pb_strat ? pb->pb_strat(pb) : pagebuf_iorequest(pb); } static inline int pagebuf_geterror(xfs_buf_t *pb) { return pb ? pb->pb_error : ENOMEM; } /* Buffer Utility Routines */ extern caddr_t pagebuf_offset( /* pointer at offset in buffer */ xfs_buf_t *, /* buffer to offset into */ size_t); /* offset */ /* Pinning Buffer Storage in Memory */ extern void pagebuf_pin( /* pin buffer in memory */ xfs_buf_t *); /* buffer to pin */ extern void pagebuf_unpin( /* unpin buffered data */ xfs_buf_t *); /* buffer to unpin */ extern int pagebuf_ispin( /* check if buffer is pinned */ xfs_buf_t *); /* buffer to check */ /* Delayed Write Buffer Routines */ extern void pagebuf_delwri_dequeue(xfs_buf_t *); /* Buffer Daemon Setup Routines */ extern int pagebuf_init(void); extern void pagebuf_terminate(void); #ifdef PAGEBUF_TRACE extern ktrace_t *pagebuf_trace_buf; extern void pagebuf_trace( xfs_buf_t *, /* buffer being traced */ char *, /* description of operation */ void *, /* arbitrary diagnostic value */ void *); /* return address */ #else # define pagebuf_trace(pb, id, ptr, ra) do { } while (0) #endif #define pagebuf_target_name(target) \ ({ char __b[BDEVNAME_SIZE]; bdevname((target)->pbr_bdev, __b); __b; }) /* These are just for xfs_syncsub... it sets an internal variable * then passes it to VOP_FLUSH_PAGES or adds the flags to a newly gotten buf_t */ #define XFS_B_ASYNC PBF_ASYNC #define XFS_B_DELWRI PBF_DELWRI #define XFS_B_READ PBF_READ #define XFS_B_WRITE PBF_WRITE #define XFS_B_STALE PBF_STALE #define XFS_BUF_TRYLOCK PBF_TRYLOCK #define XFS_INCORE_TRYLOCK PBF_TRYLOCK #define XFS_BUF_LOCK PBF_LOCK #define XFS_BUF_MAPPED PBF_MAPPED #define BUF_BUSY PBF_DONT_BLOCK #define XFS_BUF_BFLAGS(x) ((x)->pb_flags) #define XFS_BUF_ZEROFLAGS(x) \ ((x)->pb_flags &= ~(PBF_READ|PBF_WRITE|PBF_ASYNC|PBF_DELWRI)) #define XFS_BUF_STALE(x) ((x)->pb_flags |= XFS_B_STALE) #define XFS_BUF_UNSTALE(x) ((x)->pb_flags &= ~XFS_B_STALE) #define XFS_BUF_ISSTALE(x) ((x)->pb_flags & XFS_B_STALE) #define XFS_BUF_SUPER_STALE(x) do { \ XFS_BUF_STALE(x); \ pagebuf_delwri_dequeue(x); \ XFS_BUF_DONE(x); \ } while (0) #define XFS_BUF_MANAGE PBF_FS_MANAGED #define XFS_BUF_UNMANAGE(x) ((x)->pb_flags &= ~PBF_FS_MANAGED) #define XFS_BUF_DELAYWRITE(x) ((x)->pb_flags |= PBF_DELWRI) #define XFS_BUF_UNDELAYWRITE(x) pagebuf_delwri_dequeue(x) #define XFS_BUF_ISDELAYWRITE(x) ((x)->pb_flags & PBF_DELWRI) #define XFS_BUF_ERROR(x,no) pagebuf_ioerror(x,no) #define XFS_BUF_GETERROR(x) pagebuf_geterror(x) #define XFS_BUF_ISERROR(x) (pagebuf_geterror(x)?1:0) #define XFS_BUF_DONE(x) ((x)->pb_flags &= ~(PBF_PARTIAL|PBF_NONE)) #define XFS_BUF_UNDONE(x) ((x)->pb_flags |= PBF_PARTIAL|PBF_NONE) #define XFS_BUF_ISDONE(x) (!(PBF_NOT_DONE(x))) #define XFS_BUF_BUSY(x) ((x)->pb_flags |= PBF_FORCEIO) #define XFS_BUF_UNBUSY(x) ((x)->pb_flags &= ~PBF_FORCEIO) #define XFS_BUF_ISBUSY(x) (1) #define XFS_BUF_ASYNC(x) ((x)->pb_flags |= PBF_ASYNC) #define XFS_BUF_UNASYNC(x) ((x)->pb_flags &= ~PBF_ASYNC) #define XFS_BUF_ISASYNC(x) ((x)->pb_flags & PBF_ASYNC) #define XFS_BUF_FLUSH(x) ((x)->pb_flags |= PBF_FLUSH) #define XFS_BUF_UNFLUSH(x) ((x)->pb_flags &= ~PBF_FLUSH) #define XFS_BUF_ISFLUSH(x) ((x)->pb_flags & PBF_FLUSH) #define XFS_BUF_SHUT(x) printk("XFS_BUF_SHUT not implemented yet\n") #define XFS_BUF_UNSHUT(x) printk("XFS_BUF_UNSHUT not implemented yet\n") #define XFS_BUF_ISSHUT(x) (0) #define XFS_BUF_HOLD(x) pagebuf_hold(x) #define XFS_BUF_READ(x) ((x)->pb_flags |= PBF_READ) #define XFS_BUF_UNREAD(x) ((x)->pb_flags &= ~PBF_READ) #define XFS_BUF_ISREAD(x) ((x)->pb_flags & PBF_READ) #define XFS_BUF_WRITE(x) ((x)->pb_flags |= PBF_WRITE) #define XFS_BUF_UNWRITE(x) ((x)->pb_flags &= ~PBF_WRITE) #define XFS_BUF_ISWRITE(x) ((x)->pb_flags & PBF_WRITE) #define XFS_BUF_ISUNINITIAL(x) (0) #define XFS_BUF_UNUNINITIAL(x) (0) #define XFS_BUF_BP_ISMAPPED(bp) 1 #define XFS_BUF_DATAIO(x) ((x)->pb_flags |= PBF_FS_DATAIOD) #define XFS_BUF_UNDATAIO(x) ((x)->pb_flags &= ~PBF_FS_DATAIOD) #define XFS_BUF_IODONE_FUNC(buf) (buf)->pb_iodone #define XFS_BUF_SET_IODONE_FUNC(buf, func) \ (buf)->pb_iodone = (func) #define XFS_BUF_CLR_IODONE_FUNC(buf) \ (buf)->pb_iodone = NULL #define XFS_BUF_SET_BDSTRAT_FUNC(buf, func) \ (buf)->pb_strat = (func) #define XFS_BUF_CLR_BDSTRAT_FUNC(buf) \ (buf)->pb_strat = NULL #define XFS_BUF_FSPRIVATE(buf, type) \ ((type)(buf)->pb_fspriv) #define XFS_BUF_SET_FSPRIVATE(buf, value) \ (buf)->pb_fspriv = (void *)(value) #define XFS_BUF_FSPRIVATE2(buf, type) \ ((type)(buf)->pb_fspriv2) #define XFS_BUF_SET_FSPRIVATE2(buf, value) \ (buf)->pb_fspriv2 = (void *)(value) #define XFS_BUF_FSPRIVATE3(buf, type) \ ((type)(buf)->pb_fspriv3) #define XFS_BUF_SET_FSPRIVATE3(buf, value) \ (buf)->pb_fspriv3 = (void *)(value) #define XFS_BUF_SET_START(buf) #define XFS_BUF_SET_BRELSE_FUNC(buf, value) \ (buf)->pb_relse = (value) #define XFS_BUF_PTR(bp) (xfs_caddr_t)((bp)->pb_addr) extern inline xfs_caddr_t xfs_buf_offset(xfs_buf_t *bp, size_t offset) { if (bp->pb_flags & PBF_MAPPED) return XFS_BUF_PTR(bp) + offset; return (xfs_caddr_t) pagebuf_offset(bp, offset); } #define XFS_BUF_SET_PTR(bp, val, count) \ pagebuf_associate_memory(bp, val, count) #define XFS_BUF_ADDR(bp) ((bp)->pb_bn) #define XFS_BUF_SET_ADDR(bp, blk) \ ((bp)->pb_bn = (xfs_daddr_t)(blk)) #define XFS_BUF_OFFSET(bp) ((bp)->pb_file_offset) #define XFS_BUF_SET_OFFSET(bp, off) \ ((bp)->pb_file_offset = (off)) #define XFS_BUF_COUNT(bp) ((bp)->pb_count_desired) #define XFS_BUF_SET_COUNT(bp, cnt) \ ((bp)->pb_count_desired = (cnt)) #define XFS_BUF_SIZE(bp) ((bp)->pb_buffer_length) #define XFS_BUF_SET_SIZE(bp, cnt) \ ((bp)->pb_buffer_length = (cnt)) #define XFS_BUF_SET_VTYPE_REF(bp, type, ref) #define XFS_BUF_SET_VTYPE(bp, type) #define XFS_BUF_SET_REF(bp, ref) #define XFS_BUF_ISPINNED(bp) pagebuf_ispin(bp) #define XFS_BUF_VALUSEMA(bp) pagebuf_lock_value(bp) #define XFS_BUF_CPSEMA(bp) (pagebuf_cond_lock(bp) == 0) #define XFS_BUF_VSEMA(bp) pagebuf_unlock(bp) #define XFS_BUF_PSEMA(bp,x) pagebuf_lock(bp) #define XFS_BUF_V_IODONESEMA(bp) up(&bp->pb_iodonesema); /* setup the buffer target from a buftarg structure */ #define XFS_BUF_SET_TARGET(bp, target) \ (bp)->pb_target = (target) #define XFS_BUF_TARGET(bp) ((bp)->pb_target) #define XFS_BUFTARG_NAME(target) \ pagebuf_target_name(target) #define XFS_BUF_SET_VTYPE_REF(bp, type, ref) #define XFS_BUF_SET_VTYPE(bp, type) #define XFS_BUF_SET_REF(bp, ref) static inline int xfs_bawrite(void *mp, xfs_buf_t *bp) { bp->pb_fspriv3 = mp; bp->pb_strat = xfs_bdstrat_cb; pagebuf_delwri_dequeue(bp); return pagebuf_iostart(bp, PBF_WRITE | PBF_ASYNC | _PBF_RUN_QUEUES); } static inline void xfs_buf_relse(xfs_buf_t *bp) { if (!bp->pb_relse) pagebuf_unlock(bp); pagebuf_rele(bp); } #define xfs_bpin(bp) pagebuf_pin(bp) #define xfs_bunpin(bp) pagebuf_unpin(bp) #define xfs_buftrace(id, bp) \ pagebuf_trace(bp, id, NULL, (void *)__builtin_return_address(0)) #define xfs_biodone(pb) \ pagebuf_iodone(pb, (pb->pb_flags & PBF_FS_DATAIOD), 0) #define xfs_biomove(pb, off, len, data, rw) \ pagebuf_iomove((pb), (off), (len), (data), \ ((rw) == XFS_B_WRITE) ? PBRW_WRITE : PBRW_READ) #define xfs_biozero(pb, off, len) \ pagebuf_iomove((pb), (off), (len), NULL, PBRW_ZERO) static inline int XFS_bwrite(xfs_buf_t *pb) { int iowait = (pb->pb_flags & PBF_ASYNC) == 0; int error = 0; if (!iowait) pb->pb_flags |= _PBF_RUN_QUEUES; pagebuf_delwri_dequeue(pb); pagebuf_iostrategy(pb); if (iowait) { error = pagebuf_iowait(pb); xfs_buf_relse(pb); } return error; } #define XFS_bdwrite(pb) \ pagebuf_iostart(pb, PBF_DELWRI | PBF_ASYNC) static inline int xfs_bdwrite(void *mp, xfs_buf_t *bp) { bp->pb_strat = xfs_bdstrat_cb; bp->pb_fspriv3 = mp; return pagebuf_iostart(bp, PBF_DELWRI | PBF_ASYNC); } #define XFS_bdstrat(bp) pagebuf_iorequest(bp) #define xfs_iowait(pb) pagebuf_iowait(pb) #define xfs_baread(target, rablkno, ralen) \ pagebuf_readahead((target), (rablkno), (ralen), PBF_DONT_BLOCK) #define xfs_buf_get_empty(len, target) pagebuf_get_empty((len), (target)) #define xfs_buf_get_noaddr(len, target) pagebuf_get_no_daddr((len), (target)) #define xfs_buf_free(bp) pagebuf_free(bp) /* * Handling of buftargs. */ extern xfs_buftarg_t *xfs_alloc_buftarg(struct block_device *, int); extern void xfs_free_buftarg(xfs_buftarg_t *, int); extern void xfs_wait_buftarg(xfs_buftarg_t *); extern int xfs_setsize_buftarg(xfs_buftarg_t *, unsigned int, unsigned int); extern void xfs_incore_relse(xfs_buftarg_t *, int, int); extern int xfs_flush_buftarg(xfs_buftarg_t *, int); #define xfs_getsize_buftarg(buftarg) \ block_size((buftarg)->pbr_bdev) #define xfs_readonly_buftarg(buftarg) \ bdev_read_only((buftarg)->pbr_bdev) #define xfs_binval(buftarg) \ xfs_flush_buftarg(buftarg, 1) #define XFS_bflush(buftarg) \ xfs_flush_buftarg(buftarg, 1) #endif /* __XFS_BUF_H__ */