| /* |
| * 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_types.h" |
| #include "xfs_bit.h" |
| #include "xfs_log.h" |
| #include "xfs_inum.h" |
| #include "xfs_trans.h" |
| #include "xfs_sb.h" |
| #include "xfs_ag.h" |
| #include "xfs_mount.h" |
| #include "xfs_buf_item.h" |
| #include "xfs_trans_priv.h" |
| #include "xfs_error.h" |
| #include "xfs_trace.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); |
| } |
| |
| |
| #ifdef XFS_TRANS_DEBUG |
| /* |
| * This function uses an alternate strategy for tracking the bytes |
| * that the user requests to be logged. This can then be used |
| * in conjunction with the bli_orig array in the buf log item to |
| * catch bugs in our callers' code. |
| * |
| * We also double check the bits set in xfs_buf_item_log using a |
| * simple algorithm to check that every byte is accounted for. |
| */ |
| STATIC void |
| xfs_buf_item_log_debug( |
| xfs_buf_log_item_t *bip, |
| uint first, |
| uint last) |
| { |
| uint x; |
| uint byte; |
| uint nbytes; |
| uint chunk_num; |
| uint word_num; |
| uint bit_num; |
| uint bit_set; |
| uint *wordp; |
| |
| ASSERT(bip->bli_logged != NULL); |
| byte = first; |
| nbytes = last - first + 1; |
| bfset(bip->bli_logged, first, nbytes); |
| for (x = 0; x < nbytes; x++) { |
| chunk_num = byte >> XFS_BLF_SHIFT; |
| word_num = chunk_num >> BIT_TO_WORD_SHIFT; |
| bit_num = chunk_num & (NBWORD - 1); |
| wordp = &(bip->bli_format.blf_data_map[word_num]); |
| bit_set = *wordp & (1 << bit_num); |
| ASSERT(bit_set); |
| byte++; |
| } |
| } |
| |
| /* |
| * This function is called when we flush something into a buffer without |
| * logging it. This happens for things like inodes which are logged |
| * separately from the buffer. |
| */ |
| void |
| xfs_buf_item_flush_log_debug( |
| xfs_buf_t *bp, |
| uint first, |
| uint last) |
| { |
| xfs_buf_log_item_t *bip = bp->b_fspriv; |
| uint nbytes; |
| |
| if (bip == NULL || (bip->bli_item.li_type != XFS_LI_BUF)) |
| return; |
| |
| ASSERT(bip->bli_logged != NULL); |
| nbytes = last - first + 1; |
| bfset(bip->bli_logged, first, nbytes); |
| } |
| |
| /* |
| * This function is called to verify that our callers have logged |
| * all the bytes that they changed. |
| * |
| * It does this by comparing the original copy of the buffer stored in |
| * the buf log item's bli_orig array to the current copy of the buffer |
| * and ensuring that all bytes which mismatch are set in the bli_logged |
| * array of the buf log item. |
| */ |
| STATIC void |
| xfs_buf_item_log_check( |
| xfs_buf_log_item_t *bip) |
| { |
| char *orig; |
| char *buffer; |
| int x; |
| xfs_buf_t *bp; |
| |
| ASSERT(bip->bli_orig != NULL); |
| ASSERT(bip->bli_logged != NULL); |
| |
| bp = bip->bli_buf; |
| ASSERT(XFS_BUF_COUNT(bp) > 0); |
| ASSERT(bp->b_addr != NULL); |
| orig = bip->bli_orig; |
| buffer = bp->b_addr; |
| for (x = 0; x < XFS_BUF_COUNT(bp); x++) { |
| if (orig[x] != buffer[x] && !btst(bip->bli_logged, x)) { |
| xfs_emerg(bp->b_mount, |
| "%s: bip %x buffer %x orig %x index %d", |
| __func__, bip, bp, orig, x); |
| ASSERT(0); |
| } |
| } |
| } |
| #else |
| #define xfs_buf_item_log_debug(x,y,z) |
| #define xfs_buf_item_log_check(x) |
| #endif |
| |
| STATIC void xfs_buf_do_callbacks(struct xfs_buf *bp); |
| |
| /* |
| * 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 uint |
| xfs_buf_item_size( |
| struct xfs_log_item *lip) |
| { |
| struct xfs_buf_log_item *bip = BUF_ITEM(lip); |
| struct xfs_buf *bp = bip->bli_buf; |
| uint nvecs; |
| int next_bit; |
| int last_bit; |
| |
| 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); |
| return 1; |
| } |
| |
| ASSERT(bip->bli_flags & XFS_BLI_LOGGED); |
| nvecs = 1; |
| last_bit = xfs_next_bit(bip->bli_format.blf_data_map, |
| bip->bli_format.blf_map_size, 0); |
| ASSERT(last_bit != -1); |
| nvecs++; |
| 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(bip->bli_format.blf_data_map, |
| bip->bli_format.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) { |
| last_bit = -1; |
| } 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++; |
| } |
| } |
| |
| trace_xfs_buf_item_size(bip); |
| return nvecs; |
| } |
| |
| /* |
| * 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_iovec *vecp) |
| { |
| struct xfs_buf_log_item *bip = BUF_ITEM(lip); |
| struct xfs_buf *bp = bip->bli_buf; |
| uint base_size; |
| uint nvecs; |
| int first_bit; |
| int last_bit; |
| int next_bit; |
| uint nbits; |
| uint buffer_offset; |
| |
| ASSERT(atomic_read(&bip->bli_refcount) > 0); |
| ASSERT((bip->bli_flags & XFS_BLI_LOGGED) || |
| (bip->bli_flags & XFS_BLI_STALE)); |
| |
| /* |
| * The size of the base structure is the size of the |
| * declared structure plus the space for the extra words |
| * of the bitmap. We subtract one from the map size, because |
| * the first element of the bitmap is accounted for in the |
| * size of the base structure. |
| */ |
| base_size = |
| (uint)(sizeof(xfs_buf_log_format_t) + |
| ((bip->bli_format.blf_map_size - 1) * sizeof(uint))); |
| vecp->i_addr = &bip->bli_format; |
| vecp->i_len = base_size; |
| vecp->i_type = XLOG_REG_TYPE_BFORMAT; |
| vecp++; |
| nvecs = 1; |
| |
| /* |
| * If it is an inode buffer, transfer the in-memory state to the |
| * format flags and clear the in-memory state. 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. |
| */ |
| if (bip->bli_flags & XFS_BLI_INODE_BUF) { |
| if (!((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_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(bip->bli_format.blf_flags & XFS_BLF_CANCEL); |
| bip->bli_format.blf_size = nvecs; |
| return; |
| } |
| |
| /* |
| * Fill in an iovec for each set of contiguous chunks. |
| */ |
| first_bit = xfs_next_bit(bip->bli_format.blf_data_map, |
| bip->bli_format.blf_map_size, 0); |
| ASSERT(first_bit != -1); |
| 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(bip->bli_format.blf_data_map, |
| bip->bli_format.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) { |
| buffer_offset = first_bit * XFS_BLF_CHUNK; |
| vecp->i_addr = xfs_buf_offset(bp, buffer_offset); |
| vecp->i_len = nbits * XFS_BLF_CHUNK; |
| vecp->i_type = XLOG_REG_TYPE_BCHUNK; |
| nvecs++; |
| break; |
| } else if (next_bit != last_bit + 1) { |
| buffer_offset = first_bit * XFS_BLF_CHUNK; |
| vecp->i_addr = xfs_buf_offset(bp, buffer_offset); |
| vecp->i_len = nbits * XFS_BLF_CHUNK; |
| vecp->i_type = XLOG_REG_TYPE_BCHUNK; |
| nvecs++; |
| vecp++; |
| first_bit = next_bit; |
| last_bit = next_bit; |
| nbits = 1; |
| } else if (xfs_buf_offset(bp, next_bit << XFS_BLF_SHIFT) != |
| (xfs_buf_offset(bp, last_bit << XFS_BLF_SHIFT) + |
| XFS_BLF_CHUNK)) { |
| buffer_offset = first_bit * XFS_BLF_CHUNK; |
| vecp->i_addr = xfs_buf_offset(bp, buffer_offset); |
| vecp->i_len = nbits * XFS_BLF_CHUNK; |
| vecp->i_type = XLOG_REG_TYPE_BCHUNK; |
| /* You would think we need to bump the nvecs here too, but we do not |
| * this number is used by recovery, and it gets confused by the boundary |
| * split here |
| * nvecs++; |
| */ |
| vecp++; |
| first_bit = next_bit; |
| last_bit = next_bit; |
| nbits = 1; |
| } else { |
| last_bit++; |
| nbits++; |
| } |
| } |
| bip->bli_format.blf_size = nvecs; |
| |
| /* |
| * Check to make sure everything is consistent. |
| */ |
| trace_xfs_buf_item_format(bip); |
| xfs_buf_item_log_check(bip); |
| } |
| |
| /* |
| * 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_STALE)); |
| |
| trace_xfs_buf_item_pin(bip); |
| |
| atomic_inc(&bip->bli_refcount); |
| atomic_inc(&bip->bli_buf->b_pin_count); |
| } |
| |
| /* |
| * 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(!(XFS_BUF_ISDELAYWRITE(bp))); |
| ASSERT(XFS_BUF_ISSTALE(bp)); |
| 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, (xfs_log_item_t *)bip); |
| xfs_buf_item_relse(bp); |
| ASSERT(bp->b_fspriv == NULL); |
| } |
| xfs_buf_relse(bp); |
| } else if (freed && remove) { |
| xfs_buf_lock(bp); |
| xfs_buf_ioerror(bp, EIO); |
| XFS_BUF_UNDONE(bp); |
| xfs_buf_stale(bp); |
| xfs_buf_ioend(bp, 0); |
| } |
| } |
| |
| /* |
| * This is called to attempt to lock the buffer associated with this |
| * buf log item. Don't sleep on the buffer lock. If we can't get |
| * the lock right away, return 0. If we can get the lock, take a |
| * reference to the buffer. If this is a delayed write buffer that |
| * needs AIL help to be written back, invoke the pushbuf routine |
| * rather than the normal success path. |
| */ |
| STATIC uint |
| xfs_buf_item_trylock( |
| struct xfs_log_item *lip) |
| { |
| struct xfs_buf_log_item *bip = BUF_ITEM(lip); |
| struct xfs_buf *bp = bip->bli_buf; |
| |
| if (xfs_buf_ispinned(bp)) |
| return XFS_ITEM_PINNED; |
| if (!xfs_buf_trylock(bp)) |
| return XFS_ITEM_LOCKED; |
| |
| /* take a reference to the buffer. */ |
| xfs_buf_hold(bp); |
| |
| ASSERT(!(bip->bli_flags & XFS_BLI_STALE)); |
| trace_xfs_buf_item_trylock(bip); |
| if (XFS_BUF_ISDELAYWRITE(bp)) |
| return XFS_ITEM_PUSHBUF; |
| return XFS_ITEM_SUCCESS; |
| } |
| |
| /* |
| * 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; |
| int aborted; |
| uint hold; |
| |
| /* 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) != 0; |
| |
| /* |
| * Before possibly freeing the buf item, determine if we should |
| * release the buffer at the end of this routine. |
| */ |
| hold = bip->bli_flags & XFS_BLI_HOLD; |
| |
| /* Clear the per transaction state. */ |
| bip->bli_flags &= ~(XFS_BLI_LOGGED | XFS_BLI_HOLD); |
| |
| /* |
| * 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 (bip->bli_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 (xfs_bitmap_empty(bip->bli_format.blf_data_map, |
| bip->bli_format.blf_map_size)) |
| xfs_buf_item_relse(bp); |
| else |
| atomic_dec(&bip->bli_refcount); |
| |
| if (!hold) |
| xfs_buf_relse(bp); |
| } |
| |
| /* |
| * 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; |
| } |
| |
| /* |
| * The buffer is locked, but is not a delayed write buffer. |
| */ |
| STATIC void |
| xfs_buf_item_push( |
| struct xfs_log_item *lip) |
| { |
| struct xfs_buf_log_item *bip = BUF_ITEM(lip); |
| struct xfs_buf *bp = bip->bli_buf; |
| |
| ASSERT(!(bip->bli_flags & XFS_BLI_STALE)); |
| ASSERT(!XFS_BUF_ISDELAYWRITE(bp)); |
| |
| trace_xfs_buf_item_push(bip); |
| |
| xfs_buf_delwri_queue(bp); |
| xfs_buf_relse(bp); |
| } |
| |
| /* |
| * The buffer is locked and is a delayed write buffer. Promote the buffer |
| * in the delayed write queue as the caller knows that they must invoke |
| * the xfsbufd to get this buffer written. We have to unlock the buffer |
| * to allow the xfsbufd to write it, too. |
| */ |
| STATIC bool |
| xfs_buf_item_pushbuf( |
| struct xfs_log_item *lip) |
| { |
| struct xfs_buf_log_item *bip = BUF_ITEM(lip); |
| struct xfs_buf *bp = bip->bli_buf; |
| |
| ASSERT(!(bip->bli_flags & XFS_BLI_STALE)); |
| ASSERT(XFS_BUF_ISDELAYWRITE(bp)); |
| |
| trace_xfs_buf_item_pushbuf(bip); |
| |
| xfs_buf_delwri_promote(bp); |
| xfs_buf_relse(bp); |
| return true; |
| } |
| |
| STATIC void |
| xfs_buf_item_committing( |
| struct xfs_log_item *lip, |
| xfs_lsn_t commit_lsn) |
| { |
| } |
| |
| /* |
| * 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_trylock = xfs_buf_item_trylock, |
| .iop_unlock = xfs_buf_item_unlock, |
| .iop_committed = xfs_buf_item_committed, |
| .iop_push = xfs_buf_item_push, |
| .iop_pushbuf = xfs_buf_item_pushbuf, |
| .iop_committing = xfs_buf_item_committing |
| }; |
| |
| |
| /* |
| * 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. |
| */ |
| void |
| xfs_buf_item_init( |
| xfs_buf_t *bp, |
| xfs_mount_t *mp) |
| { |
| xfs_log_item_t *lip = bp->b_fspriv; |
| xfs_buf_log_item_t *bip; |
| int chunks; |
| int map_size; |
| |
| /* |
| * 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; |
| |
| /* |
| * 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. |
| */ |
| chunks = (int)((XFS_BUF_COUNT(bp) + (XFS_BLF_CHUNK - 1)) >> XFS_BLF_SHIFT); |
| map_size = (int)((chunks + NBWORD) >> BIT_TO_WORD_SHIFT); |
| |
| bip = (xfs_buf_log_item_t*)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; |
| xfs_buf_hold(bp); |
| bip->bli_format.blf_type = XFS_LI_BUF; |
| bip->bli_format.blf_blkno = (__int64_t)XFS_BUF_ADDR(bp); |
| bip->bli_format.blf_len = (ushort)BTOBB(XFS_BUF_COUNT(bp)); |
| bip->bli_format.blf_map_size = map_size; |
| |
| #ifdef XFS_TRANS_DEBUG |
| /* |
| * Allocate the arrays for tracking what needs to be logged |
| * and what our callers request to be logged. bli_orig |
| * holds a copy of the original, clean buffer for comparison |
| * against, and bli_logged keeps a 1 bit flag per byte in |
| * the buffer to indicate which bytes the callers have asked |
| * to have logged. |
| */ |
| bip->bli_orig = (char *)kmem_alloc(XFS_BUF_COUNT(bp), KM_SLEEP); |
| memcpy(bip->bli_orig, bp->b_addr, XFS_BUF_COUNT(bp)); |
| bip->bli_logged = (char *)kmem_zalloc(XFS_BUF_COUNT(bp) / NBBY, KM_SLEEP); |
| #endif |
| |
| /* |
| * 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; |
| } |
| |
| |
| /* |
| * 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) |
| { |
| 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; |
| |
| /* |
| * Mark the item as having some dirty data for |
| * quick reference in xfs_buf_item_dirty. |
| */ |
| bip->bli_flags |= XFS_BLI_DIRTY; |
| |
| /* |
| * 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 = &(bip->bli_format.blf_data_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 = ((1 << (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 = (1 << end_bit) - 1; |
| *wordp |= mask; |
| } |
| |
| xfs_buf_item_log_debug(bip, first, last); |
| } |
| |
| |
| /* |
| * Return 1 if the buffer has some data that has been logged (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); |
| } |
| |
| STATIC void |
| xfs_buf_item_free( |
| xfs_buf_log_item_t *bip) |
| { |
| #ifdef XFS_TRANS_DEBUG |
| kmem_free(bip->bli_orig); |
| kmem_free(bip->bli_logged); |
| #endif /* XFS_TRANS_DEBUG */ |
| |
| kmem_zone_free(xfs_buf_item_zone, bip); |
| } |
| |
| /* |
| * 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; |
| |
| trace_xfs_buf_item_relse(bp, _RET_IP_); |
| |
| bip = bp->b_fspriv; |
| 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); |
| } |
| |
| |
| /* |
| * 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; |
| } |
| |
| /* |
| * 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); |
| } |
| } |
| |
| /* |
| * This is the iodone() function for buffers which have had callbacks |
| * attached to them by xfs_buf_attach_iodone(). It should remove each |
| * log item from the buffer's list and call the callback of each in turn. |
| * When done, the buffer's fsprivate field is set to NULL and the buffer |
| * is unlocked with a call to iodone(). |
| */ |
| void |
| xfs_buf_iodone_callbacks( |
| 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; |
| |
| if (likely(!xfs_buf_geterror(bp))) |
| goto do_callbacks; |
| |
| /* |
| * 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)) { |
| xfs_buf_stale(bp); |
| XFS_BUF_DONE(bp); |
| trace_xfs_buf_item_iodone(bp, _RET_IP_); |
| goto do_callbacks; |
| } |
| |
| if (bp->b_target != lasttarg || |
| time_after(jiffies, (lasttime + 5*HZ))) { |
| lasttime = jiffies; |
| xfs_buf_ioerror_alert(bp, __func__); |
| } |
| lasttarg = bp->b_target; |
| |
| /* |
| * If the write was asynchronous then no one will be looking for the |
| * error. Clear the error state and write the buffer out again. |
| * |
| * During sync or umount we'll write all pending buffers again |
| * synchronous, which will catch these errors if they keep hanging |
| * around. |
| */ |
| if (XFS_BUF_ISASYNC(bp)) { |
| xfs_buf_ioerror(bp, 0); /* errno of 0 unsets the flag */ |
| |
| if (!XFS_BUF_ISSTALE(bp)) { |
| xfs_buf_delwri_queue(bp); |
| XFS_BUF_DONE(bp); |
| } |
| ASSERT(bp->b_iodone != NULL); |
| trace_xfs_buf_item_iodone_async(bp, _RET_IP_); |
| xfs_buf_relse(bp); |
| return; |
| } |
| |
| /* |
| * If the write of the buffer was synchronous, we want to make |
| * sure to return the error to the caller of xfs_bwrite(). |
| */ |
| xfs_buf_stale(bp); |
| XFS_BUF_DONE(bp); |
| |
| trace_xfs_buf_error_relse(bp, _RET_IP_); |
| |
| do_callbacks: |
| xfs_buf_do_callbacks(bp); |
| bp->b_fspriv = NULL; |
| bp->b_iodone = NULL; |
| xfs_buf_ioend(bp, 0); |
| } |
| |
| /* |
| * 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); |
| xfs_buf_item_free(BUF_ITEM(lip)); |
| } |