cregit-Linux how code gets into the kernel

Release 4.11 fs/xfs/xfs_buf_item.c

Directory: fs/xfs
/*
 * 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
 */
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_format.h"
#include "xfs_log_format.h"
#include "xfs_trans_resv.h"
#include "xfs_bit.h"
#include "xfs_sb.h"
#include "xfs_mount.h"
#include "xfs_trans.h"
#include "xfs_buf_item.h"
#include "xfs_trans_priv.h"
#include "xfs_error.h"
#include "xfs_trace.h"
#include "xfs_log.h"



kmem_zone_t	*xfs_buf_item_zone;


static inline struct xfs_buf_log_item *BUF_ITEM(struct xfs_log_item *lip) { return container_of(lip, struct xfs_buf_log_item, bli_item); }

Contributors

PersonTokensPropCommitsCommitProp
Christoph Hellwig25100.00%1100.00%
Total25100.00%1100.00%

STATIC void xfs_buf_do_callbacks(struct xfs_buf *bp);
static inline int xfs_buf_log_format_size( struct xfs_buf_log_format *blfp) { return offsetof(struct xfs_buf_log_format, blf_data_map) + (blfp->blf_map_size * sizeof(blfp->blf_data_map[0])); }

Contributors

PersonTokensPropCommitsCommitProp
Dave Chinner37100.00%1100.00%
Total37100.00%1100.00%

/* * This returns the number of log iovecs needed to log the * given buf log item. * * It calculates this as 1 iovec for the buf log format structure * and 1 for each stretch of non-contiguous chunks to be logged. * Contiguous chunks are logged in a single iovec. * * If the XFS_BLI_STALE flag has been set, then log nothing. */
STATIC void xfs_buf_item_size_segment( struct xfs_buf_log_item *bip, struct xfs_buf_log_format *blfp, int *nvecs, int *nbytes) { struct xfs_buf *bp = bip->bli_buf; int next_bit; int last_bit; last_bit = xfs_next_bit(blfp->blf_data_map, blfp->blf_map_size, 0); if (last_bit == -1) return; /* * initial count for a dirty buffer is 2 vectors - the format structure * and the first dirty region. */ *nvecs += 2; *nbytes += xfs_buf_log_format_size(blfp) + XFS_BLF_CHUNK; while (last_bit != -1) { /* * This takes the bit number to start looking from and * returns the next set bit from there. It returns -1 * if there are no more bits set or the start bit is * beyond the end of the bitmap. */ next_bit = xfs_next_bit(blfp->blf_data_map, blfp->blf_map_size, last_bit + 1); /* * If we run out of bits, leave the loop, * else if we find a new set of bits bump the number of vecs, * else keep scanning the current set of bits. */ if (next_bit == -1) { break; } else if (next_bit != last_bit + 1) { last_bit = next_bit; (*nvecs)++; } else if (xfs_buf_offset(bp, next_bit * XFS_BLF_CHUNK) != (xfs_buf_offset(bp, last_bit * XFS_BLF_CHUNK) + XFS_BLF_CHUNK)) { last_bit = next_bit; (*nvecs)++; } else { last_bit++; } *nbytes += XFS_BLF_CHUNK; } }

Contributors

PersonTokensPropCommitsCommitProp
Christoph Hellwig12969.73%342.86%
Dave Chinner5529.73%342.86%
Russell Cattelan10.54%114.29%
Total185100.00%7100.00%

/* * This returns the number of log iovecs needed to log the given buf log item. * * It calculates this as 1 iovec for the buf log format structure and 1 for each * stretch of non-contiguous chunks to be logged. Contiguous chunks are logged * in a single iovec. * * Discontiguous buffers need a format structure per region that that is being * logged. This makes the changes in the buffer appear to log recovery as though * they came from separate buffers, just like would occur if multiple buffers * were used instead of a single discontiguous buffer. This enables * discontiguous buffers to be in-memory constructs, completely transparent to * what ends up on disk. * * If the XFS_BLI_STALE flag has been set, then log nothing but the buf log * format structures. */
STATIC void xfs_buf_item_size( struct xfs_log_item *lip, int *nvecs, int *nbytes) { struct xfs_buf_log_item *bip = BUF_ITEM(lip); int i; ASSERT(atomic_read(&bip->bli_refcount) > 0); if (bip->bli_flags & XFS_BLI_STALE) { /* * The buffer is stale, so all we need to log * is the buf log format structure with the * cancel flag in it. */ trace_xfs_buf_item_size_stale(bip); ASSERT(bip->__bli_format.blf_flags & XFS_BLF_CANCEL); *nvecs += bip->bli_format_count; for (i = 0; i < bip->bli_format_count; i++) { *nbytes += xfs_buf_log_format_size(&bip->bli_formats[i]); } return; } ASSERT(bip->bli_flags & XFS_BLI_LOGGED); if (bip->bli_flags & XFS_BLI_ORDERED) { /* * The buffer has been logged just to order it. * It is not being included in the transaction * commit, so no vectors are used at all. */ trace_xfs_buf_item_size_ordered(bip); *nvecs = XFS_LOG_VEC_ORDERED; return; } /* * the vector count is based on the number of buffer vectors we have * dirty bits in. This will only be greater than one when we have a * compound buffer with more than one segment dirty. Hence for compound * buffers we need to track which segment the dirty bits correspond to, * and when we move from one segment to the next increment the vector * count for the extra buf log format structure that will need to be * written. */ for (i = 0; i < bip->bli_format_count; i++) { xfs_buf_item_size_segment(bip, &bip->bli_formats[i], nvecs, nbytes); } trace_xfs_buf_item_size(bip); }

Contributors

PersonTokensPropCommitsCommitProp
Dave Chinner14881.32%228.57%
Christoph Hellwig189.89%342.86%
David Chinner158.24%114.29%
Mark Tinguely10.55%114.29%
Total182100.00%7100.00%


static inline void xfs_buf_item_copy_iovec( struct xfs_log_vec *lv, struct xfs_log_iovec **vecp, struct xfs_buf *bp, uint offset, int first_bit, uint nbits) { offset += first_bit * XFS_BLF_CHUNK; xlog_copy_iovec(lv, vecp, XLOG_REG_TYPE_BCHUNK, xfs_buf_offset(bp, offset), nbits * XFS_BLF_CHUNK); }

Contributors

PersonTokensPropCommitsCommitProp
Christoph Hellwig5798.28%375.00%
Dave Chinner11.72%125.00%
Total58100.00%4100.00%


static inline bool xfs_buf_item_straddle( struct xfs_buf *bp, uint offset, int next_bit, int last_bit) { return xfs_buf_offset(bp, offset + (next_bit << XFS_BLF_SHIFT)) != (xfs_buf_offset(bp, offset + (last_bit << XFS_BLF_SHIFT)) + XFS_BLF_CHUNK); }

Contributors

PersonTokensPropCommitsCommitProp
Christoph Hellwig52100.00%1100.00%
Total52100.00%1100.00%


static void xfs_buf_item_format_segment( struct xfs_buf_log_item *bip, struct xfs_log_vec *lv, struct xfs_log_iovec **vecp, uint offset, struct xfs_buf_log_format *blfp) { struct xfs_buf *bp = bip->bli_buf; uint base_size; int first_bit; int last_bit; int next_bit; uint nbits; /* copy the flags across from the base format item */ blfp->blf_flags = bip->__bli_format.blf_flags; /* * Base size is the actual size of the ondisk structure - it reflects * the actual size of the dirty bitmap rather than the size of the in * memory structure. */ base_size = xfs_buf_log_format_size(blfp); first_bit = xfs_next_bit(blfp->blf_data_map, blfp->blf_map_size, 0); if (!(bip->bli_flags & XFS_BLI_STALE) && first_bit == -1) { /* * If the map is not be dirty in the transaction, mark * the size as zero and do not advance the vector pointer. */ return; } blfp = xlog_copy_iovec(lv, vecp, XLOG_REG_TYPE_BFORMAT, blfp, base_size); blfp->blf_size = 1; if (bip->bli_flags & XFS_BLI_STALE) { /* * The buffer is stale, so all we need to log * is the buf log format structure with the * cancel flag in it. */ trace_xfs_buf_item_format_stale(bip); ASSERT(blfp->blf_flags & XFS_BLF_CANCEL); return; } /* * Fill in an iovec for each set of contiguous chunks. */ last_bit = first_bit; nbits = 1; for (;;) { /* * This takes the bit number to start looking from and * returns the next set bit from there. It returns -1 * if there are no more bits set or the start bit is * beyond the end of the bitmap. */ next_bit = xfs_next_bit(blfp->blf_data_map, blfp->blf_map_size, (uint)last_bit + 1); /* * If we run out of bits fill in the last iovec and get out of * the loop. Else if we start a new set of bits then fill in * the iovec for the series we were looking at and start * counting the bits in the new one. Else we're still in the * same set of bits so just keep counting and scanning. */ if (next_bit == -1) { xfs_buf_item_copy_iovec(lv, vecp, bp, offset, first_bit, nbits); blfp->blf_size++; break; } else if (next_bit != last_bit + 1 || xfs_buf_item_straddle(bp, offset, next_bit, last_bit)) { xfs_buf_item_copy_iovec(lv, vecp, bp, offset, first_bit, nbits); blfp->blf_size++; first_bit = next_bit; last_bit = next_bit; nbits = 1; } else { last_bit++; nbits++; } } }

Contributors

PersonTokensPropCommitsCommitProp
Christoph Hellwig18363.99%640.00%
Dave Chinner6623.08%533.33%
Mark Tinguely3512.24%213.33%
Russell Cattelan10.35%16.67%
Timothy Shimmin10.35%16.67%
Total286100.00%15100.00%

/* * This is called to fill in the vector of log iovecs for the * given log buf item. It fills the first entry with a buf log * format structure, and the rest point to contiguous chunks * within the buffer. */
STATIC void xfs_buf_item_format( struct xfs_log_item *lip, struct xfs_log_vec *lv) { struct xfs_buf_log_item *bip = BUF_ITEM(lip); struct xfs_buf *bp = bip->bli_buf; struct xfs_log_iovec *vecp = NULL; uint offset = 0; int i; ASSERT(atomic_read(&bip->bli_refcount) > 0); ASSERT((bip->bli_flags & XFS_BLI_LOGGED) || (bip->bli_flags & XFS_BLI_STALE)); ASSERT((bip->bli_flags & XFS_BLI_STALE) || (xfs_blft_from_flags(&bip->__bli_format) > XFS_BLFT_UNKNOWN_BUF && xfs_blft_from_flags(&bip->__bli_format) < XFS_BLFT_MAX_BUF)); /* * If it is an inode buffer, transfer the in-memory state to the * format flags and clear the in-memory state. * * For buffer based inode allocation, we do not transfer * this state if the inode buffer allocation has not yet been committed * to the log as setting the XFS_BLI_INODE_BUF flag will prevent * correct replay of the inode allocation. * * For icreate item based inode allocation, the buffers aren't written * to the journal during allocation, and hence we should always tag the * buffer as an inode buffer so that the correct unlinked list replay * occurs during recovery. */ if (bip->bli_flags & XFS_BLI_INODE_BUF) { if (xfs_sb_version_hascrc(&lip->li_mountp->m_sb) || !((bip->bli_flags & XFS_BLI_INODE_ALLOC_BUF) && xfs_log_item_in_current_chkpt(lip))) bip->__bli_format.blf_flags |= XFS_BLF_INODE_BUF; bip->bli_flags &= ~XFS_BLI_INODE_BUF; } if ((bip->bli_flags & (XFS_BLI_ORDERED|XFS_BLI_STALE)) == XFS_BLI_ORDERED) { /* * The buffer has been logged just to order it. It is not being * included in the transaction commit, so don't format it. */ trace_xfs_buf_item_format_ordered(bip); return; } for (i = 0; i < bip->bli_format_count; i++) { xfs_buf_item_format_segment(bip, lv, &vecp, offset, &bip->bli_formats[i]); offset += BBTOB(bp->b_maps[i].bm_len); } /* * Check to make sure everything is consistent. */ trace_xfs_buf_item_format(bip); }

Contributors

PersonTokensPropCommitsCommitProp
Dave Chinner18172.11%216.67%
David Chinner3614.34%216.67%
Christoph Hellwig2911.55%541.67%
Brian Foster31.20%18.33%
Mark Tinguely10.40%18.33%
Stephen Lord10.40%18.33%
Total251100.00%12100.00%

/* * This is called to pin the buffer associated with the buf log item in memory * so it cannot be written out. * * We also always take a reference to the buffer log item here so that the bli * is held while the item is pinned in memory. This means that we can * unconditionally drop the reference count a transaction holds when the * transaction is completed. */
STATIC void xfs_buf_item_pin( struct xfs_log_item *lip) { struct xfs_buf_log_item *bip = BUF_ITEM(lip); ASSERT(atomic_read(&bip->bli_refcount) > 0); ASSERT((bip->bli_flags & XFS_BLI_LOGGED) || (bip->bli_flags & XFS_BLI_ORDERED) || (bip->bli_flags & XFS_BLI_STALE)); trace_xfs_buf_item_pin(bip); atomic_inc(&bip->bli_refcount); atomic_inc(&bip->bli_buf->b_pin_count); }

Contributors

PersonTokensPropCommitsCommitProp
Christoph Hellwig7285.71%466.67%
David Chinner89.52%116.67%
Dave Chinner44.76%116.67%
Total84100.00%6100.00%

/* * This is called to unpin the buffer associated with the buf log * item which was previously pinned with a call to xfs_buf_item_pin(). * * Also drop the reference to the buf item for the current transaction. * If the XFS_BLI_STALE flag is set and we are the last reference, * then free up the buf log item and unlock the buffer. * * If the remove flag is set we are called from uncommit in the * forced-shutdown path. If that is true and the reference count on * the log item is going to drop to zero we need to free the item's * descriptor in the transaction. */
STATIC void xfs_buf_item_unpin( struct xfs_log_item *lip, int remove) { struct xfs_buf_log_item *bip = BUF_ITEM(lip); xfs_buf_t *bp = bip->bli_buf; struct xfs_ail *ailp = lip->li_ailp; int stale = bip->bli_flags & XFS_BLI_STALE; int freed; ASSERT(bp->b_fspriv == bip); ASSERT(atomic_read(&bip->bli_refcount) > 0); trace_xfs_buf_item_unpin(bip); freed = atomic_dec_and_test(&bip->bli_refcount); if (atomic_dec_and_test(&bp->b_pin_count)) wake_up_all(&bp->b_waiters); if (freed && stale) { ASSERT(bip->bli_flags & XFS_BLI_STALE); ASSERT(xfs_buf_islocked(bp)); ASSERT(bp->b_flags & XBF_STALE); ASSERT(bip->__bli_format.blf_flags & XFS_BLF_CANCEL); trace_xfs_buf_item_unpin_stale(bip); if (remove) { /* * If we are in a transaction context, we have to * remove the log item from the transaction as we are * about to release our reference to the buffer. If we * don't, the unlock that occurs later in * xfs_trans_uncommit() will try to reference the * buffer which we no longer have a hold on. */ if (lip->li_desc) xfs_trans_del_item(lip); /* * Since the transaction no longer refers to the buffer, * the buffer should no longer refer to the transaction. */ bp->b_transp = NULL; } /* * If we get called here because of an IO error, we may * or may not have the item on the AIL. xfs_trans_ail_delete() * will take care of that situation. * xfs_trans_ail_delete() drops the AIL lock. */ if (bip->bli_flags & XFS_BLI_STALE_INODE) { xfs_buf_do_callbacks(bp); bp->b_fspriv = NULL; bp->b_iodone = NULL; } else { spin_lock(&ailp->xa_lock); xfs_trans_ail_delete(ailp, lip, SHUTDOWN_LOG_IO_ERROR); xfs_buf_item_relse(bp); ASSERT(bp->b_fspriv == NULL); } xfs_buf_relse(bp); } else if (freed && remove) { /* * There are currently two references to the buffer - the active * LRU reference and the buf log item. What we are about to do * here - simulate a failed IO completion - requires 3 * references. * * The LRU reference is removed by the xfs_buf_stale() call. The * buf item reference is removed by the xfs_buf_iodone() * callback that is run by xfs_buf_do_callbacks() during ioend * processing (via the bp->b_iodone callback), and then finally * the ioend processing will drop the IO reference if the buffer * is marked XBF_ASYNC. * * Hence we need to take an additional reference here so that IO * completion processing doesn't free the buffer prematurely. */ xfs_buf_lock(bp); xfs_buf_hold(bp); bp->b_flags |= XBF_ASYNC; xfs_buf_ioerror(bp, -EIO); bp->b_flags &= ~XBF_DONE; xfs_buf_stale(bp); xfs_buf_ioend(bp); } }

Contributors

PersonTokensPropCommitsCommitProp
Christoph Hellwig21972.76%1144.00%
Stephen Lord309.97%28.00%
Dave Chinner309.97%728.00%
David Chinner196.31%312.00%
Donald Douwsma20.66%14.00%
Mark Tinguely10.33%14.00%
Total301100.00%25100.00%

/* * Buffer IO error rate limiting. Limit it to no more than 10 messages per 30 * seconds so as to not spam logs too much on repeated detection of the same * buffer being bad.. */ static DEFINE_RATELIMIT_STATE(xfs_buf_write_fail_rl_state, 30 * HZ, 10);
STATIC uint xfs_buf_item_push( struct xfs_log_item *lip, struct list_head *buffer_list) { struct xfs_buf_log_item *bip = BUF_ITEM(lip); struct xfs_buf *bp = bip->bli_buf; uint rval = XFS_ITEM_SUCCESS; if (xfs_buf_ispinned(bp)) return XFS_ITEM_PINNED; if (!xfs_buf_trylock(bp)) { /* * If we have just raced with a buffer being pinned and it has * been marked stale, we could end up stalling until someone else * issues a log force to unpin the stale buffer. Check for the * race condition here so xfsaild recognizes the buffer is pinned * and queues a log force to move it along. */ if (xfs_buf_ispinned(bp)) return XFS_ITEM_PINNED; return XFS_ITEM_LOCKED; } ASSERT(!(bip->bli_flags & XFS_BLI_STALE)); trace_xfs_buf_item_push(bip); /* has a previous flush failed due to IO errors? */ if ((bp->b_flags & XBF_WRITE_FAIL) && ___ratelimit(&xfs_buf_write_fail_rl_state, "XFS: Failing async write")) { xfs_warn(bp->b_target->bt_mount, "Failing async write on buffer block 0x%llx. Retrying async write.", (long long)bp->b_bn); } if (!xfs_buf_delwri_queue(bp, buffer_list)) rval = XFS_ITEM_FLUSHING; xfs_buf_unlock(bp); return rval; }

Contributors

PersonTokensPropCommitsCommitProp
Christoph Hellwig9260.13%550.00%
Dave Chinner3824.84%110.00%
Brian Foster138.50%110.00%
David Chinner74.58%110.00%
Eric Sandeen21.31%110.00%
Chandra Seetharaman10.65%110.00%
Total153100.00%10100.00%

/* * Release the buffer associated with the buf log item. If there is no dirty * logged data associated with the buffer recorded in the buf log item, then * free the buf log item and remove the reference to it in the buffer. * * This call ignores the recursion count. It is only called when the buffer * should REALLY be unlocked, regardless of the recursion count. * * We unconditionally drop the transaction's reference to the log item. If the * item was logged, then another reference was taken when it was pinned, so we * can safely drop the transaction reference now. This also allows us to avoid * potential races with the unpin code freeing the bli by not referencing the * bli after we've dropped the reference count. * * If the XFS_BLI_HOLD flag is set in the buf log item, then free the log item * if necessary but do not unlock the buffer. This is for support of * xfs_trans_bhold(). Make sure the XFS_BLI_HOLD field is cleared if we don't * free the item. */
STATIC void xfs_buf_item_unlock( struct xfs_log_item *lip) { struct xfs_buf_log_item *bip = BUF_ITEM(lip); struct xfs_buf *bp = bip->bli_buf; bool clean; bool aborted; int flags; /* Clear the buffer's association with this transaction. */ bp->b_transp = NULL; /* * If this is a transaction abort, don't return early. Instead, allow * the brelse to happen. Normally it would be done for stale * (cancelled) buffers at unpin time, but we'll never go through the * pin/unpin cycle if we abort inside commit. */ aborted = (lip->li_flags & XFS_LI_ABORTED) ? true : false; /* * Before possibly freeing the buf item, copy the per-transaction state * so we can reference it safely later after clearing it from the * buffer log item. */ flags = bip->bli_flags; bip->bli_flags &= ~(XFS_BLI_LOGGED | XFS_BLI_HOLD | XFS_BLI_ORDERED); /* * If the buf item is marked stale, then don't do anything. We'll * unlock the buffer and free the buf item when the buffer is unpinned * for the last time. */ if (flags & XFS_BLI_STALE) { trace_xfs_buf_item_unlock_stale(bip); ASSERT(bip->__bli_format.blf_flags & XFS_BLF_CANCEL); if (!aborted) { atomic_dec(&bip->bli_refcount); return; } } trace_xfs_buf_item_unlock(bip); /* * If the buf item isn't tracking any data, free it, otherwise drop the * reference we hold to it. If we are aborting the transaction, this may * be the only reference to the buf item, so we free it anyway * regardless of whether it is dirty or not. A dirty abort implies a * shutdown, anyway. * * Ordered buffers are dirty but may have no recorded changes, so ensure * we only release clean items here. */ clean = (flags & XFS_BLI_DIRTY) ? false : true; if (clean) { int i; for (i = 0; i < bip->bli_format_count; i++) { if (!xfs_bitmap_empty(bip->bli_formats[i].blf_data_map, bip->bli_formats[i].blf_map_size)) { clean = false; break; } } } /* * Clean buffers, by definition, cannot be in the AIL. However, aborted * buffers may be dirty and hence in the AIL. Therefore if we are * aborting a buffer and we've just taken the last refernce away, we * have to check if it is in the AIL before freeing it. We need to free * it in this case, because an aborted transaction has already shut the * filesystem down and this is the last chance we will have to do so. */ if (atomic_dec_and_test(&bip->bli_refcount)) { if (clean) xfs_buf_item_relse(bp); else if (aborted) { ASSERT(XFS_FORCED_SHUTDOWN(lip->li_mountp)); xfs_trans_ail_remove(lip, SHUTDOWN_LOG_IO_ERROR); xfs_buf_item_relse(bp); } } if (!(flags & XFS_BLI_HOLD)) xfs_buf_relse(bp); }

Contributors

PersonTokensPropCommitsCommitProp
Christoph Hellwig11744.66%533.33%
Dave Chinner6625.19%533.33%
David Chinner4015.27%16.67%
Mark Tinguely3714.12%213.33%
Eric Sandeen10.38%16.67%
Brian Foster10.38%16.67%
Total262100.00%15100.00%

/* * This is called to find out where the oldest active copy of the * buf log item in the on disk log resides now that the last log * write of it completed at the given lsn. * We always re-log all the dirty data in a buffer, so usually the * latest copy in the on disk log is the only one that matters. For * those cases we simply return the given lsn. * * The one exception to this is for buffers full of newly allocated * inodes. These buffers are only relogged with the XFS_BLI_INODE_BUF * flag set, indicating that only the di_next_unlinked fields from the * inodes in the buffers will be replayed during recovery. If the * original newly allocated inode images have not yet been flushed * when the buffer is so relogged, then we need to make sure that we * keep the old images in the 'active' portion of the log. We do this * by returning the original lsn of that transaction here rather than * the current one. */
STATIC xfs_lsn_t xfs_buf_item_committed( struct xfs_log_item *lip, xfs_lsn_t lsn) { struct xfs_buf_log_item *bip = BUF_ITEM(lip); trace_xfs_buf_item_committed(bip); if ((bip->bli_flags & XFS_BLI_INODE_ALLOC_BUF) && lip->li_lsn != 0) return lip->li_lsn; return lsn; }

Contributors

PersonTokensPropCommitsCommitProp
Christoph Hellwig53100.00%4100.00%
Total53100.00%4100.00%


STATIC void xfs_buf_item_committing( struct xfs_log_item *lip, xfs_lsn_t commit_lsn) { }

Contributors

PersonTokensPropCommitsCommitProp
Christoph Hellwig13100.00%3100.00%
Total13100.00%3100.00%

/* * This is the ops vector shared by all buf log items. */ static const struct xfs_item_ops xfs_buf_item_ops = { .iop_size = xfs_buf_item_size, .iop_format = xfs_buf_item_format, .iop_pin = xfs_buf_item_pin, .iop_unpin = xfs_buf_item_unpin, .iop_unlock = xfs_buf_item_unlock, .iop_committed = xfs_buf_item_committed, .iop_push = xfs_buf_item_push, .iop_committing = xfs_buf_item_committing };
STATIC int xfs_buf_item_get_format( struct xfs_buf_log_item *bip, int count) { ASSERT(bip->bli_formats == NULL); bip->bli_format_count = count; if (count == 1) { bip->bli_formats = &bip->__bli_format; return 0; } bip->bli_formats = kmem_zalloc(count * sizeof(struct xfs_buf_log_format), KM_SLEEP); if (!bip->bli_formats) return -ENOMEM; return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Dave Chinner7998.75%266.67%
Mark Tinguely11.25%133.33%
Total80100.00%3100.00%


STATIC void xfs_buf_item_free_format( struct xfs_buf_log_item *bip) { if (bip->bli_formats != &bip->__bli_format) { kmem_free(bip->bli_formats); bip->bli_formats = NULL; } }

Contributors

PersonTokensPropCommitsCommitProp
Dave Chinner3697.30%150.00%
Mark Tinguely12.70%150.00%
Total37100.00%2100.00%

/* * Allocate a new buf log item to go with the given buffer. * Set the buffer's b_fsprivate field to point to the new * buf log item. If there are other item's attached to the * buffer (see xfs_buf_attach_iodone() below), then put the * buf log item at the front. */
int xfs_buf_item_init( struct xfs_buf *bp, struct xfs_mount *mp) { struct xfs_log_item *lip = bp->b_fspriv; struct xfs_buf_log_item *bip; int chunks; int map_size; int error; int i; /* * Check to see if there is already a buf log item for * this buffer. If there is, it is guaranteed to be * the first. If we do already have one, there is * nothing to do here so return. */ ASSERT(bp->b_target->bt_mount == mp); if (lip != NULL && lip->li_type == XFS_LI_BUF) return 0; bip = kmem_zone_zalloc(xfs_buf_item_zone, KM_SLEEP); xfs_log_item_init(mp, &bip->bli_item, XFS_LI_BUF, &xfs_buf_item_ops); bip->bli_buf = bp; /* * chunks is the number of XFS_BLF_CHUNK size pieces the buffer * can be divided into. Make sure not to truncate any pieces. * map_size is the size of the bitmap needed to describe the * chunks of the buffer. * * Discontiguous buffer support follows the layout of the underlying * buffer. This makes the implementation as simple as possible. */ error = xfs_buf_item_get_format(bip, bp->b_map_count); ASSERT(error == 0); if (error) { /* to stop gcc throwing set-but-unused warnings */ kmem_zone_free(xfs_buf_item_zone, bip); return error; } for (i = 0; i < bip->bli_format_count; i++) { chunks = DIV_ROUND_UP(BBTOB(bp->b_maps[i].bm_len), XFS_BLF_CHUNK); map_size = DIV_ROUND_UP(chunks, NBWORD); bip->bli_formats[i].blf_type = XFS_LI_BUF; bip->bli_formats[i].blf_blkno = bp->b_maps[i].bm_bn; bip->bli_formats[i].blf_len = bp->b_maps[i].bm_len; bip->bli_formats[i].blf_map_size = map_size; } /* * Put the buf item into the list of items attached to the * buffer at the front. */ if (bp->b_fspriv) bip->bli_item.li_bio_list = bp->b_fspriv; bp->b_fspriv = bip; xfs_buf_hold(bp); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Dave Chinner16260.45%440.00%
Christoph Hellwig10137.69%330.00%
David Chinner41.49%220.00%
Russell Cattelan10.37%110.00%
Total268100.00%10100.00%

/* * Mark bytes first through last inclusive as dirty in the buf * item's bitmap. */
static void xfs_buf_item_log_segment( uint first, uint last, uint *map) { uint first_bit; uint last_bit; uint bits_to_set; uint bits_set; uint word_num; uint *wordp; uint bit; uint end_bit; uint mask; /* * Convert byte offsets to bit numbers. */ first_bit = first >> XFS_BLF_SHIFT; last_bit = last >> XFS_BLF_SHIFT; /* * Calculate the total number of bits to be set. */ bits_to_set = last_bit - first_bit + 1; /* * Get a pointer to the first word in the bitmap * to set a bit in. */ word_num = first_bit >> BIT_TO_WORD_SHIFT; wordp = &map[word_num]; /* * Calculate the starting bit in the first word. */ bit = first_bit & (uint)(NBWORD - 1); /* * First set any bits in the first word of our range. * If it starts at bit 0 of the word, it will be * set below rather than here. That is what the variable * bit tells us. The variable bits_set tracks the number * of bits that have been set so far. End_bit is the number * of the last bit to be set in this word plus one. */ if (bit) { end_bit = MIN(bit + bits_to_set, (uint)NBWORD); mask = ((1U << (end_bit - bit)) - 1) << bit; *wordp |= mask; wordp++; bits_set = end_bit - bit; } else { bits_set = 0; } /* * Now set bits a whole word at a time that are between * first_bit and last_bit. */ while ((bits_to_set - bits_set) >= NBWORD) { *wordp |= 0xffffffff; bits_set += NBWORD; wordp++; } /* * Finally, set any bits left to be set in one last partial word. */ end_bit = bits_to_set - bits_set; if (end_bit) { mask = (1U << end_bit) - 1; *wordp |= mask; } }

Contributors

PersonTokensPropCommitsCommitProp
Christoph Hellwig19694.23%116.67%
Dave Chinner94.33%350.00%
Xie XiuQi20.96%116.67%
Russell Cattelan10.48%116.67%
Total208100.00%6100.00%

/* * Mark bytes first through last inclusive as dirty in the buf * item's bitmap. */
void xfs_buf_item_log( xfs_buf_log_item_t *bip, uint first, uint last) { int i; uint start; uint end; struct xfs_buf *bp = bip->bli_buf; /* * walk each buffer segment and mark them dirty appropriately. */ start = 0; for (i = 0; i < bip->bli_format_count; i++) { if (start > last) break; end = start + BBTOB(bp->b_maps[i].bm_len) - 1; /* skip to the map that includes the first byte to log */ if (first > end) { start += BBTOB(bp->b_maps[i].bm_len); continue; } /* * Trim the range to this segment and mark it in the bitmap. * Note that we must convert buffer offsets to segment relative * offsets (e.g., the first byte of each segment is byte 0 of * that segment). */ if (first < start) first = start; if (end > last) end = last; xfs_buf_item_log_segment(first - start, end - start, &bip->bli_formats[i].blf_data_map[0]); start += BBTOB(bp->b_maps[i].bm_len); } }

Contributors

PersonTokensPropCommitsCommitProp
Dave Chinner15293.25%150.00%
Brian Foster116.75%150.00%
Total163100.00%2100.00%

/* * Return 1 if the buffer has been logged or ordered in a transaction (at any * point, not just the current transaction) and 0 if not. */
uint xfs_buf_item_dirty( xfs_buf_log_item_t *bip) { return (bip->bli_flags & XFS_BLI_DIRTY); }

Contributors

PersonTokensPropCommitsCommitProp
Christoph Hellwig18100.00%1100.00%
Total18100.00%1100.00%


STATIC void xfs_buf_item_free( xfs_buf_log_item_t *bip) { xfs_buf_item_free_format(bip); kmem_free(bip->bli_item.li_lv_shadow); kmem_zone_free(xfs_buf_item_zone, bip); }

Contributors

PersonTokensPropCommitsCommitProp
Lachlan McIlroy1754.84%133.33%
Dave Chinner1445.16%266.67%
Total31100.00%3100.00%

/* * This is called when the buf log item is no longer needed. It should * free the buf log item associated with the given buffer and clear * the buffer's pointer to the buf log item. If there are no more * items in the list, clear the b_iodone field of the buffer (see * xfs_buf_attach_iodone() below). */
void xfs_buf_item_relse( xfs_buf_t *bp) { xfs_buf_log_item_t *bip = bp->b_fspriv; trace_xfs_buf_item_relse(bp, _RET_IP_); ASSERT(!(bip->bli_item.li_flags & XFS_LI_IN_AIL)); bp->b_fspriv = bip->bli_item.li_bio_list; if (bp->b_fspriv == NULL) bp->b_iodone = NULL; xfs_buf_rele(bp); xfs_buf_item_free(bip); }

Contributors

PersonTokensPropCommitsCommitProp
Christoph Hellwig5475.00%466.67%
David Chinner1520.83%116.67%
Lachlan McIlroy34.17%116.67%
Total72100.00%6100.00%

/* * Add the given log item with its callback to the list of callbacks * to be called when the buffer's I/O completes. If it is not set * already, set the buffer's b_iodone() routine to be * xfs_buf_iodone_callbacks() and link the log item into the list of * items rooted at b_fsprivate. Items are always added as the second * entry in the list if there is a first, because the buf item code * assumes that the buf log item is first. */
void xfs_buf_attach_iodone( xfs_buf_t *bp, void (*cb)(xfs_buf_t *, xfs_log_item_t *), xfs_log_item_t *lip) { xfs_log_item_t *head_lip; ASSERT(xfs_buf_islocked(bp)); lip->li_cb = cb; head_lip = bp->b_fspriv; if (head_lip) { lip->li_bio_list = head_lip->li_bio_list; head_lip->li_bio_list = lip; } else { bp->b_fspriv = lip; } ASSERT(bp->b_iodone == NULL || bp->b_iodone == xfs_buf_iodone_callbacks); bp->b_iodone = xfs_buf_iodone_callbacks; }

Contributors

PersonTokensPropCommitsCommitProp
Christoph Hellwig100100.00%4100.00%
Total100100.00%4100.00%

/* * We can have many callbacks on a buffer. Running the callbacks individually * can cause a lot of contention on the AIL lock, so we allow for a single * callback to be able to scan the remaining lip->li_bio_list for other items * of the same type and callback to be processed in the first call. * * As a result, the loop walking the callback list below will also modify the * list. it removes the first item from the list and then runs the callback. * The loop then restarts from the new head of the list. This allows the * callback to scan and modify the list attached to the buffer and we don't * have to care about maintaining a next item pointer. */
STATIC void xfs_buf_do_callbacks( struct xfs_buf *bp) { struct xfs_log_item *lip; while ((lip = bp->b_fspriv) != NULL) { bp->b_fspriv = lip->li_bio_list; ASSERT(lip->li_cb != NULL); /* * Clear the next pointer so we don't have any * confusion if the item is added to another buf. * Don't touch the log item after calling its * callback, because it could have freed itself. */ lip->li_bio_list = NULL; lip->li_cb(bp, lip); } }

Contributors

PersonTokensPropCommitsCommitProp
Christoph Hellwig5384.13%266.67%
Dave Chinner1015.87%133.33%
Total63100.00%3100.00%


static bool xfs_buf_iodone_callback_error( struct xfs_buf *bp) { struct xfs_log_item *lip = bp->b_fspriv; struct xfs_mount *mp = lip->li_mountp; static ulong lasttime; static xfs_buftarg_t *lasttarg; struct xfs_error_cfg *cfg; /* * If we've already decided to shutdown the filesystem because of * I/O errors, there's no point in giving this a retry. */ if (XFS_FORCED_SHUTDOWN(mp)) goto out_stale; if (bp->b_target != lasttarg || time_after(jiffies, (lasttime + 5*HZ))) { lasttime = jiffies; xfs_buf_ioerror_alert(bp, __func__); } lasttarg = bp->b_target; /* synchronous writes will have callers process the error */ if (!(bp->b_flags & XBF_ASYNC)) goto out_stale; trace_xfs_buf_item_iodone_async(bp, _RET_IP_); ASSERT(bp->b_iodone != NULL); cfg = xfs_error_get_cfg(mp, XFS_ERR_METADATA, bp->b_error); /* * If the write was asynchronous then no one will be looking for the * error. If this is the first failure of this type, clear the error * state and write the buffer out again. This means we always retry an * async write failure at least once, but we also need to set the buffer * up to behave correctly now for repeated failures. */ if (!(bp->b_flags & (XBF_STALE | XBF_WRITE_FAIL)) || bp->b_last_error != bp->b_error) { bp->b_flags |= (XBF_WRITE | XBF_DONE | XBF_WRITE_FAIL); bp->b_last_error = bp->b_error; if (cfg->retry_timeout != XFS_ERR_RETRY_FOREVER && !bp->b_first_retry_time) bp->b_first_retry_time = jiffies; xfs_buf_ioerror(bp, 0); xfs_buf_submit(bp); return true; } /* * Repeated failure on an async write. Take action according to the * error configuration we have been set up to use. */ if (cfg->max_retries != XFS_ERR_RETRY_FOREVER && ++bp->b_retries > cfg->max_retries) goto permanent_error; if (cfg->retry_timeout != XFS_ERR_RETRY_FOREVER && time_after(jiffies, cfg->retry_timeout + bp->b_first_retry_time)) goto permanent_error; /* At unmount we may treat errors differently */ if ((mp->m_flags & XFS_MOUNT_UNMOUNTING) && mp->m_fail_unmount) goto permanent_error; /* still a transient error, higher layers will retry */ xfs_buf_ioerror(bp, 0); xfs_buf_relse(bp); return true; /* * Permanent error - we need to trigger a shutdown if we haven't already * to indicate that inconsistency will result from this action. */ permanent_error: xfs_force_shutdown(mp, SHUTDOWN_META_IO_ERROR); out_stale: xfs_buf_stale(bp); bp->b_flags |= XBF_DONE; trace_xfs_buf_error_relse(bp, _RET_IP_); return false; }

Contributors

PersonTokensPropCommitsCommitProp
Carlos Maiolino14644.24%314.29%
Christoph Hellwig12738.48%942.86%
Eric Sandeen267.88%29.52%
Dave Chinner216.36%419.05%
Stephen Lord51.52%14.76%
Chandra Seetharaman41.21%14.76%
Nathan Scott10.30%14.76%
Total330100.00%21100.00%

/* * This is the iodone() function for buffers which have had callbacks attached * to them by xfs_buf_attach_iodone(). We need to iterate the items on the * callback list, mark the buffer as having no more callbacks and then push the * buffer through IO completion processing. */
void xfs_buf_iodone_callbacks( struct xfs_buf *bp) { /* * If there is an error, process it. Some errors require us * to run callbacks after failure processing is done so we * detect that and take appropriate action. */ if (bp->b_error && xfs_buf_iodone_callback_error(bp)) return; /* * Successful IO or permanent error. Either way, we can clear the * retry state here in preparation for the next error that may occur. */ bp->b_last_error = 0; bp->b_retries = 0; bp->b_first_retry_time = 0; xfs_buf_do_callbacks(bp); bp->b_fspriv = NULL; bp->b_iodone = NULL; xfs_buf_ioend(bp); }

Contributors

PersonTokensPropCommitsCommitProp
Carlos Maiolino3554.69%228.57%
Christoph Hellwig2335.94%457.14%
Hou Tao69.38%114.29%
Total64100.00%7100.00%

/* * This is the iodone() function for buffers which have been * logged. It is called when they are eventually flushed out. * It should remove the buf item from the AIL, and free the buf item. * It is called by xfs_buf_iodone_callbacks() above which will take * care of cleaning up the buffer itself. */
void xfs_buf_iodone( struct xfs_buf *bp, struct xfs_log_item *lip) { struct xfs_ail *ailp = lip->li_ailp; ASSERT(BUF_ITEM(lip)->bli_buf == bp); xfs_buf_rele(bp); /* * If we are forcibly shutting down, this may well be * off the AIL already. That's because we simulate the * log-committed callbacks to unpin these buffers. Or we may never * have put this item on AIL because of the transaction was * aborted forcibly. xfs_trans_ail_delete() takes care of these. * * Either way, AIL is useless if we're forcing a shutdown. */ spin_lock(&ailp->xa_lock); xfs_trans_ail_delete(ailp, lip, SHUTDOWN_CORRUPT_INCORE); xfs_buf_item_free(BUF_ITEM(lip)); }

Contributors

PersonTokensPropCommitsCommitProp
Christoph Hellwig4465.67%225.00%
David Chinner1319.40%337.50%
Lachlan McIlroy68.96%112.50%
Dave Chinner22.99%112.50%
Donald Douwsma22.99%112.50%
Total67100.00%8100.00%


Overall Contributors

PersonTokensPropCommitsCommitProp
Christoph Hellwig184651.59%2527.47%
Dave Chinner113531.72%2628.57%
Carlos Maiolino1825.09%33.30%
David Chinner1624.53%1112.09%
Mark Tinguely772.15%33.30%
Stephen Lord421.17%44.40%
Eric Sandeen290.81%44.40%
Russell Cattelan280.78%22.20%
Brian Foster280.78%33.30%
Lachlan McIlroy260.73%11.10%
Hou Tao60.17%11.10%
Chandra Seetharaman50.14%22.20%
Nathan Scott50.14%33.30%
Donald Douwsma40.11%11.10%
Xie XiuQi20.06%11.10%
Timothy Shimmin10.03%11.10%
Total3578100.00%91100.00%
Directory: fs/xfs
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