diff options
Diffstat (limited to 'fs/xfs/xfs_trans_buf.c')
| -rw-r--r-- | fs/xfs/xfs_trans_buf.c | 1093 |
1 files changed, 1093 insertions, 0 deletions
diff --git a/fs/xfs/xfs_trans_buf.c b/fs/xfs/xfs_trans_buf.c new file mode 100644 index 000000000000..a9682b9510c1 --- /dev/null +++ b/fs/xfs/xfs_trans_buf.c @@ -0,0 +1,1093 @@ +/* + * Copyright (c) 2000-2002 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/ + */ + +#include "xfs.h" +#include "xfs_macros.h" +#include "xfs_types.h" +#include "xfs_inum.h" +#include "xfs_log.h" +#include "xfs_trans.h" +#include "xfs_buf_item.h" +#include "xfs_sb.h" +#include "xfs_ag.h" +#include "xfs_dir.h" +#include "xfs_dmapi.h" +#include "xfs_mount.h" +#include "xfs_trans_priv.h" +#include "xfs_error.h" +#include "xfs_rw.h" + + +STATIC xfs_buf_t *xfs_trans_buf_item_match(xfs_trans_t *, xfs_buftarg_t *, + xfs_daddr_t, int); +STATIC xfs_buf_t *xfs_trans_buf_item_match_all(xfs_trans_t *, xfs_buftarg_t *, + xfs_daddr_t, int); + + +/* + * Get and lock the buffer for the caller if it is not already + * locked within the given transaction. If it is already locked + * within the transaction, just increment its lock recursion count + * and return a pointer to it. + * + * Use the fast path function xfs_trans_buf_item_match() or the buffer + * cache routine incore_match() to find the buffer + * if it is already owned by this transaction. + * + * If we don't already own the buffer, use get_buf() to get it. + * If it doesn't yet have an associated xfs_buf_log_item structure, + * then allocate one and add the item to this transaction. + * + * If the transaction pointer is NULL, make this just a normal + * get_buf() call. + */ +xfs_buf_t * +xfs_trans_get_buf(xfs_trans_t *tp, + xfs_buftarg_t *target_dev, + xfs_daddr_t blkno, + int len, + uint flags) +{ + xfs_buf_t *bp; + xfs_buf_log_item_t *bip; + + if (flags == 0) + flags = XFS_BUF_LOCK | XFS_BUF_MAPPED; + + /* + * Default to a normal get_buf() call if the tp is NULL. + */ + if (tp == NULL) { + bp = xfs_buf_get_flags(target_dev, blkno, len, + flags | BUF_BUSY); + return(bp); + } + + /* + * If we find the buffer in the cache with this transaction + * pointer in its b_fsprivate2 field, then we know we already + * have it locked. In this case we just increment the lock + * recursion count and return the buffer to the caller. + */ + if (tp->t_items.lic_next == NULL) { + bp = xfs_trans_buf_item_match(tp, target_dev, blkno, len); + } else { + bp = xfs_trans_buf_item_match_all(tp, target_dev, blkno, len); + } + if (bp != NULL) { + ASSERT(XFS_BUF_VALUSEMA(bp) <= 0); + if (XFS_FORCED_SHUTDOWN(tp->t_mountp)) { + xfs_buftrace("TRANS GET RECUR SHUT", bp); + XFS_BUF_SUPER_STALE(bp); + } + /* + * If the buffer is stale then it was binval'ed + * since last read. This doesn't matter since the + * caller isn't allowed to use the data anyway. + */ + else if (XFS_BUF_ISSTALE(bp)) { + xfs_buftrace("TRANS GET RECUR STALE", bp); + ASSERT(!XFS_BUF_ISDELAYWRITE(bp)); + } + ASSERT(XFS_BUF_FSPRIVATE2(bp, xfs_trans_t *) == tp); + bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t *); + ASSERT(bip != NULL); + ASSERT(atomic_read(&bip->bli_refcount) > 0); + bip->bli_recur++; + xfs_buftrace("TRANS GET RECUR", bp); + xfs_buf_item_trace("GET RECUR", bip); + return (bp); + } + + /* + * We always specify the BUF_BUSY flag within a transaction so + * that get_buf does not try to push out a delayed write buffer + * which might cause another transaction to take place (if the + * buffer was delayed alloc). Such recursive transactions can + * easily deadlock with our current transaction as well as cause + * us to run out of stack space. + */ + bp = xfs_buf_get_flags(target_dev, blkno, len, flags | BUF_BUSY); + if (bp == NULL) { + return NULL; + } + + ASSERT(!XFS_BUF_GETERROR(bp)); + + /* + * The xfs_buf_log_item pointer is stored in b_fsprivate. If + * it doesn't have one yet, then allocate one and initialize it. + * The checks to see if one is there are in xfs_buf_item_init(). + */ + xfs_buf_item_init(bp, tp->t_mountp); + + /* + * Set the recursion count for the buffer within this transaction + * to 0. + */ + bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t*); + ASSERT(!(bip->bli_flags & XFS_BLI_STALE)); + ASSERT(!(bip->bli_format.blf_flags & XFS_BLI_CANCEL)); + ASSERT(!(bip->bli_flags & XFS_BLI_LOGGED)); + bip->bli_recur = 0; + + /* + * Take a reference for this transaction on the buf item. + */ + atomic_inc(&bip->bli_refcount); + + /* + * Get a log_item_desc to point at the new item. + */ + (void) xfs_trans_add_item(tp, (xfs_log_item_t*)bip); + + /* + * Initialize b_fsprivate2 so we can find it with incore_match() + * above. + */ + XFS_BUF_SET_FSPRIVATE2(bp, tp); + + xfs_buftrace("TRANS GET", bp); + xfs_buf_item_trace("GET", bip); + return (bp); +} + +/* + * Get and lock the superblock buffer of this file system for the + * given transaction. + * + * We don't need to use incore_match() here, because the superblock + * buffer is a private buffer which we keep a pointer to in the + * mount structure. + */ +xfs_buf_t * +xfs_trans_getsb(xfs_trans_t *tp, + struct xfs_mount *mp, + int flags) +{ + xfs_buf_t *bp; + xfs_buf_log_item_t *bip; + + /* + * Default to just trying to lock the superblock buffer + * if tp is NULL. + */ + if (tp == NULL) { + return (xfs_getsb(mp, flags)); + } + + /* + * If the superblock buffer already has this transaction + * pointer in its b_fsprivate2 field, then we know we already + * have it locked. In this case we just increment the lock + * recursion count and return the buffer to the caller. + */ + bp = mp->m_sb_bp; + if (XFS_BUF_FSPRIVATE2(bp, xfs_trans_t *) == tp) { + bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t*); + ASSERT(bip != NULL); + ASSERT(atomic_read(&bip->bli_refcount) > 0); + bip->bli_recur++; + xfs_buf_item_trace("GETSB RECUR", bip); + return (bp); + } + + bp = xfs_getsb(mp, flags); + if (bp == NULL) { + return NULL; + } + + /* + * The xfs_buf_log_item pointer is stored in b_fsprivate. If + * it doesn't have one yet, then allocate one and initialize it. + * The checks to see if one is there are in xfs_buf_item_init(). + */ + xfs_buf_item_init(bp, mp); + + /* + * Set the recursion count for the buffer within this transaction + * to 0. + */ + bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t*); + ASSERT(!(bip->bli_flags & XFS_BLI_STALE)); + ASSERT(!(bip->bli_format.blf_flags & XFS_BLI_CANCEL)); + ASSERT(!(bip->bli_flags & XFS_BLI_LOGGED)); + bip->bli_recur = 0; + + /* + * Take a reference for this transaction on the buf item. + */ + atomic_inc(&bip->bli_refcount); + + /* + * Get a log_item_desc to point at the new item. + */ + (void) xfs_trans_add_item(tp, (xfs_log_item_t*)bip); + + /* + * Initialize b_fsprivate2 so we can find it with incore_match() + * above. + */ + XFS_BUF_SET_FSPRIVATE2(bp, tp); + + xfs_buf_item_trace("GETSB", bip); + return (bp); +} + +#ifdef DEBUG +xfs_buftarg_t *xfs_error_target; +int xfs_do_error; +int xfs_req_num; +int xfs_error_mod = 33; +#endif + +/* + * Get and lock the buffer for the caller if it is not already + * locked within the given transaction. If it has not yet been + * read in, read it from disk. If it is already locked + * within the transaction and already read in, just increment its + * lock recursion count and return a pointer to it. + * + * Use the fast path function xfs_trans_buf_item_match() or the buffer + * cache routine incore_match() to find the buffer + * if it is already owned by this transaction. + * + * If we don't already own the buffer, use read_buf() to get it. + * If it doesn't yet have an associated xfs_buf_log_item structure, + * then allocate one and add the item to this transaction. + * + * If the transaction pointer is NULL, make this just a normal + * read_buf() call. + */ +int +xfs_trans_read_buf( + xfs_mount_t *mp, + xfs_trans_t *tp, + xfs_buftarg_t *target, + xfs_daddr_t blkno, + int len, + uint flags, + xfs_buf_t **bpp) +{ + xfs_buf_t *bp; + xfs_buf_log_item_t *bip; + int error; + + if (flags == 0) + flags = XFS_BUF_LOCK | XFS_BUF_MAPPED; + + /* + * Default to a normal get_buf() call if the tp is NULL. + */ + if (tp == NULL) { + bp = xfs_buf_read_flags(target, blkno, len, flags | BUF_BUSY); + if (!bp) + return XFS_ERROR(ENOMEM); + + if ((bp != NULL) && (XFS_BUF_GETERROR(bp) != 0)) { + xfs_ioerror_alert("xfs_trans_read_buf", mp, + bp, blkno); + error = XFS_BUF_GETERROR(bp); + xfs_buf_relse(bp); + return error; + } +#ifdef DEBUG + if (xfs_do_error && (bp != NULL)) { + if (xfs_error_target == target) { + if (((xfs_req_num++) % xfs_error_mod) == 0) { + xfs_buf_relse(bp); + printk("Returning error!\n"); + return XFS_ERROR(EIO); + } + } + } +#endif + if (XFS_FORCED_SHUTDOWN(mp)) + goto shutdown_abort; + *bpp = bp; + return 0; + } + + /* + * If we find the buffer in the cache with this transaction + * pointer in its b_fsprivate2 field, then we know we already + * have it locked. If it is already read in we just increment + * the lock recursion count and return the buffer to the caller. + * If the buffer is not yet read in, then we read it in, increment + * the lock recursion count, and return it to the caller. + */ + if (tp->t_items.lic_next == NULL) { + bp = xfs_trans_buf_item_match(tp, target, blkno, len); + } else { + bp = xfs_trans_buf_item_match_all(tp, target, blkno, len); + } + if (bp != NULL) { + ASSERT(XFS_BUF_VALUSEMA(bp) <= 0); + ASSERT(XFS_BUF_FSPRIVATE2(bp, xfs_trans_t *) == tp); + ASSERT(XFS_BUF_FSPRIVATE(bp, void *) != NULL); + ASSERT((XFS_BUF_ISERROR(bp)) == 0); + if (!(XFS_BUF_ISDONE(bp))) { + xfs_buftrace("READ_BUF_INCORE !DONE", bp); + ASSERT(!XFS_BUF_ISASYNC(bp)); + XFS_BUF_READ(bp); + xfsbdstrat(tp->t_mountp, bp); + xfs_iowait(bp); + if (XFS_BUF_GETERROR(bp) != 0) { + xfs_ioerror_alert("xfs_trans_read_buf", mp, + bp, blkno); + error = XFS_BUF_GETERROR(bp); + xfs_buf_relse(bp); + /* + * We can gracefully recover from most + * read errors. Ones we can't are those + * that happen after the transaction's + * already dirty. + */ + if (tp->t_flags & XFS_TRANS_DIRTY) + xfs_force_shutdown(tp->t_mountp, + XFS_METADATA_IO_ERROR); + return error; + } + } + /* + * We never locked this buf ourselves, so we shouldn't + * brelse it either. Just get out. + */ + if (XFS_FORCED_SHUTDOWN(mp)) { + xfs_buftrace("READ_BUF_INCORE XFSSHUTDN", bp); + *bpp = NULL; + return XFS_ERROR(EIO); + } + + + bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t*); + bip->bli_recur++; + + ASSERT(atomic_read(&bip->bli_refcount) > 0); + xfs_buf_item_trace("READ RECUR", bip); + *bpp = bp; + return 0; + } + + /* + * We always specify the BUF_BUSY flag within a transaction so + * that get_buf does not try to push out a delayed write buffer + * which might cause another transaction to take place (if the + * buffer was delayed alloc). Such recursive transactions can + * easily deadlock with our current transaction as well as cause + * us to run out of stack space. + */ + bp = xfs_buf_read_flags(target, blkno, len, flags | BUF_BUSY); + if (bp == NULL) { + *bpp = NULL; + return 0; + } + if (XFS_BUF_GETERROR(bp) != 0) { + XFS_BUF_SUPER_STALE(bp); + xfs_buftrace("READ ERROR", bp); + error = XFS_BUF_GETERROR(bp); + + xfs_ioerror_alert("xfs_trans_read_buf", mp, + bp, blkno); + if (tp->t_flags & XFS_TRANS_DIRTY) + xfs_force_shutdown(tp->t_mountp, XFS_METADATA_IO_ERROR); + xfs_buf_relse(bp); + return error; + } +#ifdef DEBUG + if (xfs_do_error && !(tp->t_flags & XFS_TRANS_DIRTY)) { + if (xfs_error_target == target) { + if (((xfs_req_num++) % xfs_error_mod) == 0) { + xfs_force_shutdown(tp->t_mountp, + XFS_METADATA_IO_ERROR); + xfs_buf_relse(bp); + printk("Returning error in trans!\n"); + return XFS_ERROR(EIO); + } + } + } +#endif + if (XFS_FORCED_SHUTDOWN(mp)) + goto shutdown_abort; + + /* + * The xfs_buf_log_item pointer is stored in b_fsprivate. If + * it doesn't have one yet, then allocate one and initialize it. + * The checks to see if one is there are in xfs_buf_item_init(). + */ + xfs_buf_item_init(bp, tp->t_mountp); + + /* + * Set the recursion count for the buffer within this transaction + * to 0. + */ + bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t*); + ASSERT(!(bip->bli_flags & XFS_BLI_STALE)); + ASSERT(!(bip->bli_format.blf_flags & XFS_BLI_CANCEL)); + ASSERT(!(bip->bli_flags & XFS_BLI_LOGGED)); + bip->bli_recur = 0; + + /* + * Take a reference for this transaction on the buf item. + */ + atomic_inc(&bip->bli_refcount); + + /* + * Get a log_item_desc to point at the new item. + */ + (void) xfs_trans_add_item(tp, (xfs_log_item_t*)bip); + + /* + * Initialize b_fsprivate2 so we can find it with incore_match() + * above. + */ + XFS_BUF_SET_FSPRIVATE2(bp, tp); + + xfs_buftrace("TRANS READ", bp); + xfs_buf_item_trace("READ", bip); + *bpp = bp; + return 0; + +shutdown_abort: + /* + * the theory here is that buffer is good but we're + * bailing out because the filesystem is being forcibly + * shut down. So we should leave the b_flags alone since + * the buffer's not staled and just get out. + */ +#if defined(DEBUG) + if (XFS_BUF_ISSTALE(bp) && XFS_BUF_ISDELAYWRITE(bp)) + cmn_err(CE_NOTE, "about to pop assert, bp == 0x%p", bp); +#endif + ASSERT((XFS_BUF_BFLAGS(bp) & (XFS_B_STALE|XFS_B_DELWRI)) != + (XFS_B_STALE|XFS_B_DELWRI)); + + xfs_buftrace("READ_BUF XFSSHUTDN", bp); + xfs_buf_relse(bp); + *bpp = NULL; + return XFS_ERROR(EIO); +} + + +/* + * Release the buffer bp which was previously acquired with one of the + * xfs_trans_... buffer allocation routines if the buffer has not + * been modified within this transaction. If the buffer is modified + * within this transaction, do decrement the recursion count but do + * not release the buffer even if the count goes to 0. If the buffer is not + * modified within the transaction, decrement the recursion count and + * release the buffer if the recursion count goes to 0. + * + * If the buffer is to be released and it was not modified before + * this transaction began, then free the buf_log_item associated with it. + * + * If the transaction pointer is NULL, make this just a normal + * brelse() call. + */ +void +xfs_trans_brelse(xfs_trans_t *tp, + xfs_buf_t *bp) +{ + xfs_buf_log_item_t *bip; + xfs_log_item_t *lip; + xfs_log_item_desc_t *lidp; + + /* + * Default to a normal brelse() call if the tp is NULL. + */ + if (tp == NULL) { + ASSERT(XFS_BUF_FSPRIVATE2(bp, void *) == NULL); + /* + * If there's a buf log item attached to the buffer, + * then let the AIL know that the buffer is being + * unlocked. + */ + if (XFS_BUF_FSPRIVATE(bp, void *) != NULL) { + lip = XFS_BUF_FSPRIVATE(bp, xfs_log_item_t *); + if (lip->li_type == XFS_LI_BUF) { + bip = XFS_BUF_FSPRIVATE(bp,xfs_buf_log_item_t*); + xfs_trans_unlocked_item( + bip->bli_item.li_mountp, + lip); + } + } + xfs_buf_relse(bp); + return; + } + + ASSERT(XFS_BUF_FSPRIVATE2(bp, xfs_trans_t *) == tp); + bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t *); + ASSERT(bip->bli_item.li_type == XFS_LI_BUF); + ASSERT(!(bip->bli_flags & XFS_BLI_STALE)); + ASSERT(!(bip->bli_format.blf_flags & XFS_BLI_CANCEL)); + ASSERT(atomic_read(&bip->bli_refcount) > 0); + + /* + * Find the item descriptor pointing to this buffer's + * log item. It must be there. + */ + lidp = xfs_trans_find_item(tp, (xfs_log_item_t*)bip); + ASSERT(lidp != NULL); + + /* + * If the release is just for a recursive lock, + * then decrement the count and return. + */ + if (bip->bli_recur > 0) { + bip->bli_recur--; + xfs_buf_item_trace("RELSE RECUR", bip); + return; + } + + /* + * If the buffer is dirty within this transaction, we can't + * release it until we commit. + */ + if (lidp->lid_flags & XFS_LID_DIRTY) { + xfs_buf_item_trace("RELSE DIRTY", bip); + return; + } + + /* + * If the buffer has been invalidated, then we can't release + * it until the transaction commits to disk unless it is re-dirtied + * as part of this transaction. This prevents us from pulling + * the item from the AIL before we should. + */ + if (bip->bli_flags & XFS_BLI_STALE) { + xfs_buf_item_trace("RELSE STALE", bip); + return; + } + + ASSERT(!(bip->bli_flags & XFS_BLI_LOGGED)); + xfs_buf_item_trace("RELSE", bip); + + /* + * Free up the log item descriptor tracking the released item. + */ + xfs_trans_free_item(tp, lidp); + + /* + * Clear the hold flag in the buf log item if it is set. + * We wouldn't want the next user of the buffer to + * get confused. + */ + if (bip->bli_flags & XFS_BLI_HOLD) { + bip->bli_flags &= ~XFS_BLI_HOLD; + } + + /* + * Drop our reference to the buf log item. + */ + atomic_dec(&bip->bli_refcount); + + /* + * If the buf item is not tracking data in the log, then + * we must free it before releasing the buffer back to the + * free pool. Before releasing the buffer to the free pool, + * clear the transaction pointer in b_fsprivate2 to dissolve + * its relation to this transaction. + */ + if (!xfs_buf_item_dirty(bip)) { +/*** + ASSERT(bp->b_pincount == 0); +***/ + ASSERT(atomic_read(&bip->bli_refcount) == 0); + ASSERT(!(bip->bli_item.li_flags & XFS_LI_IN_AIL)); + ASSERT(!(bip->bli_flags & XFS_BLI_INODE_ALLOC_BUF)); + xfs_buf_item_relse(bp); + bip = NULL; + } + XFS_BUF_SET_FSPRIVATE2(bp, NULL); + + /* + * If we've still got a buf log item on the buffer, then + * tell the AIL that the buffer is being unlocked. + */ + if (bip != NULL) { + xfs_trans_unlocked_item(bip->bli_item.li_mountp, + (xfs_log_item_t*)bip); + } + + xfs_buf_relse(bp); + return; +} + +/* + * Add the locked buffer to the transaction. + * The buffer must be locked, and it cannot be associated with any + * transaction. + * + * If the buffer does not yet have a buf log item associated with it, + * then allocate one for it. Then add the buf item to the transaction. + */ +void +xfs_trans_bjoin(xfs_trans_t *tp, + xfs_buf_t *bp) +{ + xfs_buf_log_item_t *bip; + + ASSERT(XFS_BUF_ISBUSY(bp)); + ASSERT(XFS_BUF_FSPRIVATE2(bp, void *) == NULL); + + /* + * The xfs_buf_log_item pointer is stored in b_fsprivate. If + * it doesn't have one yet, then allocate one and initialize it. + * The checks to see if one is there are in xfs_buf_item_init(). + */ + xfs_buf_item_init(bp, tp->t_mountp); + bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t *); + ASSERT(!(bip->bli_flags & XFS_BLI_STALE)); + ASSERT(!(bip->bli_format.blf_flags & XFS_BLI_CANCEL)); + ASSERT(!(bip->bli_flags & XFS_BLI_LOGGED)); + + /* + * Take a reference for this transaction on the buf item. + */ + atomic_inc(&bip->bli_refcount); + + /* + * Get a log_item_desc to point at the new item. + */ + (void) xfs_trans_add_item(tp, (xfs_log_item_t *)bip); + + /* + * Initialize b_fsprivate2 so we can find it with incore_match() + * in xfs_trans_get_buf() and friends above. + */ + XFS_BUF_SET_FSPRIVATE2(bp, tp); + + xfs_buf_item_trace("BJOIN", bip); +} + +/* + * Mark the buffer as not needing to be unlocked when the buf item's + * IOP_UNLOCK() routine is called. The buffer must already be locked + * and associated with the given transaction. + */ +/* ARGSUSED */ +void +xfs_trans_bhold(xfs_trans_t *tp, + xfs_buf_t *bp) +{ + xfs_buf_log_item_t *bip; + + ASSERT(XFS_BUF_ISBUSY(bp)); + ASSERT(XFS_BUF_FSPRIVATE2(bp, xfs_trans_t *) == tp); + ASSERT(XFS_BUF_FSPRIVATE(bp, void *) != NULL); + + bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t *); + ASSERT(!(bip->bli_flags & XFS_BLI_STALE)); + ASSERT(!(bip->bli_format.blf_flags & XFS_BLI_CANCEL)); + ASSERT(atomic_read(&bip->bli_refcount) > 0); + bip->bli_flags |= XFS_BLI_HOLD; + xfs_buf_item_trace("BHOLD", bip); +} + +/* + * This is called to mark bytes first through last inclusive of the given + * buffer as needing to be logged when the transaction is committed. + * The buffer must already be associated with the given transaction. + * + * First and last are numbers relative to the beginning of this buffer, + * so the first byte in the buffer is numbered 0 regardless of the + * value of b_blkno. + */ +void +xfs_trans_log_buf(xfs_trans_t *tp, + xfs_buf_t *bp, + uint first, + uint last) +{ + xfs_buf_log_item_t *bip; + xfs_log_item_desc_t *lidp; + + ASSERT(XFS_BUF_ISBUSY(bp)); + ASSERT(XFS_BUF_FSPRIVATE2(bp, xfs_trans_t *) == tp); + ASSERT(XFS_BUF_FSPRIVATE(bp, void *) != NULL); + ASSERT((first <= last) && (last < XFS_BUF_COUNT(bp))); + ASSERT((XFS_BUF_IODONE_FUNC(bp) == NULL) || + (XFS_BUF_IODONE_FUNC(bp) == xfs_buf_iodone_callbacks)); + + /* + * Mark the buffer as needing to be written out eventually, + * and set its iodone function to remove the buffer's buf log + * item from the AIL and free it when the buffer is flushed + * to disk. See xfs_buf_attach_iodone() for more details + * on li_cb and xfs_buf_iodone_callbacks(). + * If we end up aborting this transaction, we trap this buffer + * inside the b_bdstrat callback so that this won't get written to + * disk. + */ + XFS_BUF_DELAYWRITE(bp); + XFS_BUF_DONE(bp); + + bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t *); + ASSERT(atomic_read(&bip->bli_refcount) > 0); + XFS_BUF_SET_IODONE_FUNC(bp, xfs_buf_iodone_callbacks); + bip->bli_item.li_cb = (void(*)(xfs_buf_t*,xfs_log_item_t*))xfs_buf_iodone; + + /* + * If we invalidated the buffer within this transaction, then + * cancel the invalidation now that we're dirtying the buffer + * again. There are no races with the code in xfs_buf_item_unpin(), + * because we have a reference to the buffer this entire time. + */ + if (bip->bli_flags & XFS_BLI_STALE) { + xfs_buf_item_trace("BLOG UNSTALE", bip); + bip->bli_flags &= ~XFS_BLI_STALE; + ASSERT(XFS_BUF_ISSTALE(bp)); + XFS_BUF_UNSTALE(bp); + bip->bli_format.blf_flags &= ~XFS_BLI_CANCEL; + } + + lidp = xfs_trans_find_item(tp, (xfs_log_item_t*)bip); + ASSERT(lidp != NULL); + + tp->t_flags |= XFS_TRANS_DIRTY; + lidp->lid_flags |= XFS_LID_DIRTY; + lidp->lid_flags &= ~XFS_LID_BUF_STALE; + bip->bli_flags |= XFS_BLI_LOGGED; + xfs_buf_item_log(bip, first, last); + xfs_buf_item_trace("BLOG", bip); +} + + +/* + * This called to invalidate a buffer that is being used within + * a transaction. Typically this is because the blocks in the + * buffer are being freed, so we need to prevent it from being + * written out when we're done. Allowing it to be written again + * might overwrite data in the free blocks if they are reallocated + * to a file. + * + * We prevent the buffer from being written out by clearing the + * B_DELWRI flag. We can't always + * get rid of the buf log item at this point, though, because + * the buffer may still be pinned by another transaction. If that + * is the case, then we'll wait until the buffer is committed to + * disk for the last time (we can tell by the ref count) and + * free it in xfs_buf_item_unpin(). Until it is cleaned up we + * will keep the buffer locked so that the buffer and buf log item + * are not reused. + */ +void +xfs_trans_binval( + xfs_trans_t *tp, + xfs_buf_t *bp) +{ + xfs_log_item_desc_t *lidp; + xfs_buf_log_item_t *bip; + + ASSERT(XFS_BUF_ISBUSY(bp)); + ASSERT(XFS_BUF_FSPRIVATE2(bp, xfs_trans_t *) == tp); + ASSERT(XFS_BUF_FSPRIVATE(bp, void *) != NULL); + + bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t *); + lidp = xfs_trans_find_item(tp, (xfs_log_item_t*)bip); + ASSERT(lidp != NULL); + ASSERT(atomic_read(&bip->bli_refcount) > 0); + + if (bip->bli_flags & XFS_BLI_STALE) { + /* + * If the buffer is already invalidated, then + * just return. + */ + ASSERT(!(XFS_BUF_ISDELAYWRITE(bp))); + ASSERT(XFS_BUF_ISSTALE(bp)); + ASSERT(!(bip->bli_flags & (XFS_BLI_LOGGED | XFS_BLI_DIRTY))); + ASSERT(!(bip->bli_format.blf_flags & XFS_BLI_INODE_BUF)); + ASSERT(bip->bli_format.blf_flags & XFS_BLI_CANCEL); + ASSERT(lidp->lid_flags & XFS_LID_DIRTY); + ASSERT(tp->t_flags & XFS_TRANS_DIRTY); + xfs_buftrace("XFS_BINVAL RECUR", bp); + xfs_buf_item_trace("BINVAL RECUR", bip); + return; + } + + /* + * Clear the dirty bit in the buffer and set the STALE flag + * in the buf log item. The STALE flag will be used in + * xfs_buf_item_unpin() to determine if it should clean up + * when the last reference to the buf item is given up. + * We set the XFS_BLI_CANCEL flag in the buf log format structure + * and log the buf item. This will be used at recovery time + * to determine that copies of the buffer in the log before + * this should not be replayed. + * We mark the item descriptor and the transaction dirty so + * that we'll hold the buffer until after the commit. + * + * Since we're invalidating the buffer, we also clear the state + * about which parts of the buffer have been logged. We also + * clear the flag indicating that this is an inode buffer since + * the data in the buffer will no longer be valid. + * + * We set the stale bit in the buffer as well since we're getting + * rid of it. + */ + XFS_BUF_UNDELAYWRITE(bp); + XFS_BUF_STALE(bp); + bip->bli_flags |= XFS_BLI_STALE; + bip->bli_flags &= ~(XFS_BLI_LOGGED | XFS_BLI_DIRTY); + bip->bli_format.blf_flags &= ~XFS_BLI_INODE_BUF; + bip->bli_format.blf_flags |= XFS_BLI_CANCEL; + memset((char *)(bip->bli_format.blf_data_map), 0, + (bip->bli_format.blf_map_size * sizeof(uint))); + lidp->lid_flags |= XFS_LID_DIRTY|XFS_LID_BUF_STALE; + tp->t_flags |= XFS_TRANS_DIRTY; + xfs_buftrace("XFS_BINVAL", bp); + xfs_buf_item_trace("BINVAL", bip); +} + +/* + * This call is used to indicate that the buffer contains on-disk + * inodes which must be handled specially during recovery. They + * require special handling because only the di_next_unlinked from + * the inodes in the buffer should be recovered. The rest of the + * data in the buffer is logged via the inodes themselves. + * + * All we do is set the XFS_BLI_INODE_BUF flag in the buffer's log + * format structure so that we'll know what to do at recovery time. + */ +/* ARGSUSED */ +void +xfs_trans_inode_buf( + xfs_trans_t *tp, + xfs_buf_t *bp) +{ + xfs_buf_log_item_t *bip; + + ASSERT(XFS_BUF_ISBUSY(bp)); + ASSERT(XFS_BUF_FSPRIVATE2(bp, xfs_trans_t *) == tp); + ASSERT(XFS_BUF_FSPRIVATE(bp, void *) != NULL); + + bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t *); + ASSERT(atomic_read(&bip->bli_refcount) > 0); + + bip->bli_format.blf_flags |= XFS_BLI_INODE_BUF; +} + +/* + * This call is used to indicate that the buffer is going to + * be staled and was an inode buffer. This means it gets + * special processing during unpin - where any inodes + * associated with the buffer should be removed from ail. + * There is also special processing during recovery, + * any replay of the inodes in the buffer needs to be + * prevented as the buffer may have been reused. + */ +void +xfs_trans_stale_inode_buf( + xfs_trans_t *tp, + xfs_buf_t *bp) +{ + xfs_buf_log_item_t *bip; + + ASSERT(XFS_BUF_ISBUSY(bp)); + ASSERT(XFS_BUF_FSPRIVATE2(bp, xfs_trans_t *) == tp); + ASSERT(XFS_BUF_FSPRIVATE(bp, void *) != NULL); + + bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t *); + ASSERT(atomic_read(&bip->bli_refcount) > 0); + + bip->bli_flags |= XFS_BLI_STALE_INODE; + bip->bli_item.li_cb = (void(*)(xfs_buf_t*,xfs_log_item_t*)) + xfs_buf_iodone; +} + + + +/* + * Mark the buffer as being one which contains newly allocated + * inodes. We need to make sure that even if this buffer is + * relogged as an 'inode buf' we still recover all of the inode + * images in the face of a crash. This works in coordination with + * xfs_buf_item_committed() to ensure that the buffer remains in the + * AIL at its original location even after it has been relogged. + */ +/* ARGSUSED */ +void +xfs_trans_inode_alloc_buf( + xfs_trans_t *tp, + xfs_buf_t *bp) +{ + xfs_buf_log_item_t *bip; + + ASSERT(XFS_BUF_ISBUSY(bp)); + ASSERT(XFS_BUF_FSPRIVATE2(bp, xfs_trans_t *) == tp); + ASSERT(XFS_BUF_FSPRIVATE(bp, void *) != NULL); + + bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t *); + ASSERT(atomic_read(&bip->bli_refcount) > 0); + + bip->bli_flags |= XFS_BLI_INODE_ALLOC_BUF; +} + + +/* + * Similar to xfs_trans_inode_buf(), this marks the buffer as a cluster of + * dquots. However, unlike in inode buffer recovery, dquot buffers get + * recovered in their entirety. (Hence, no XFS_BLI_DQUOT_ALLOC_BUF flag). + * The only thing that makes dquot buffers different from regular + * buffers is that we must not replay dquot bufs when recovering + * if a _corresponding_ quotaoff has happened. We also have to distinguish + * between usr dquot bufs and grp dquot bufs, because usr and grp quotas + * can be turned off independently. + */ +/* ARGSUSED */ +void +xfs_trans_dquot_buf( + xfs_trans_t *tp, + xfs_buf_t *bp, + uint type) +{ + xfs_buf_log_item_t *bip; + + ASSERT(XFS_BUF_ISBUSY(bp)); + ASSERT(XFS_BUF_FSPRIVATE2(bp, xfs_trans_t *) == tp); + ASSERT(XFS_BUF_FSPRIVATE(bp, void *) != NULL); + ASSERT(type == XFS_BLI_UDQUOT_BUF || + type == XFS_BLI_GDQUOT_BUF); + + bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t *); + ASSERT(atomic_read(&bip->bli_refcount) > 0); + + bip->bli_format.blf_flags |= type; +} + +/* + * Check to see if a buffer matching the given parameters is already + * a part of the given transaction. Only check the first, embedded + * chunk, since we don't want to spend all day scanning large transactions. + */ +STATIC xfs_buf_t * +xfs_trans_buf_item_match( + xfs_trans_t *tp, + xfs_buftarg_t *target, + xfs_daddr_t blkno, + int len) +{ + xfs_log_item_chunk_t *licp; + xfs_log_item_desc_t *lidp; + xfs_buf_log_item_t *blip; + xfs_buf_t *bp; + int i; + + bp = NULL; + len = BBTOB(len); + licp = &tp->t_items; + if (!XFS_LIC_ARE_ALL_FREE(licp)) { + for (i = 0; i < licp->lic_unused; i++) { + /* + * Skip unoccupied slots. + */ + if (XFS_LIC_ISFREE(licp, i)) { + continue; + } + + lidp = XFS_LIC_SLOT(licp, i); + blip = (xfs_buf_log_item_t *)lidp->lid_item; + if (blip->bli_item.li_type != XFS_LI_BUF) { + continue; + } + + bp = blip->bli_buf; + if ((XFS_BUF_TARGET(bp) == target) && + (XFS_BUF_ADDR(bp) == blkno) && + (XFS_BUF_COUNT(bp) == len)) { + /* + * We found it. Break out and + * return the pointer to the buffer. + */ + break; + } else { + bp = NULL; + } + } + } + return bp; +} + +/* + * Check to see if a buffer matching the given parameters is already + * a part of the given transaction. Check all the chunks, we + * want to be thorough. + */ +STATIC xfs_buf_t * +xfs_trans_buf_item_match_all( + xfs_trans_t *tp, + xfs_buftarg_t *target, + xfs_daddr_t blkno, + int len) +{ + xfs_log_item_chunk_t *licp; + xfs_log_item_desc_t *lidp; + xfs_buf_log_item_t *blip; + xfs_buf_t *bp; + int i; + + bp = NULL; + len = BBTOB(len); + for (licp = &tp->t_items; licp != NULL; licp = licp->lic_next) { + if (XFS_LIC_ARE_ALL_FREE(licp)) { + ASSERT(licp == &tp->t_items); + ASSERT(licp->lic_next == NULL); + return NULL; + } + for (i = 0; i < licp->lic_unused; i++) { + /* + * Skip unoccupied slots. + */ + if (XFS_LIC_ISFREE(licp, i)) { + continue; + } + + lidp = XFS_LIC_SLOT(licp, i); + blip = (xfs_buf_log_item_t *)lidp->lid_item; + if (blip->bli_item.li_type != XFS_LI_BUF) { + continue; + } + + bp = blip->bli_buf; + if ((XFS_BUF_TARGET(bp) == target) && + (XFS_BUF_ADDR(bp) == blkno) && + (XFS_BUF_COUNT(bp) == len)) { + /* + * We found it. Break out and + * return the pointer to the buffer. + */ + return bp; + } + } + } + return NULL; +} |
