X-Git-Url: http://git.cascardo.eti.br/?a=blobdiff_plain;f=fs%2Fxfs%2Fxfs_buf_item.c;h=02a80984aa05f13189f4c99f186f1f098fa02e3d;hb=f1bbbb6912662b9f6070c5bfc4ca9eb1f06a9d5b;hp=240340a4727b9b17080f7f50810a456f8eafaf0f;hpb=677abe49ad017679627af9d3bbd9a7ecb3d94c42;p=cascardo%2Flinux.git diff --git a/fs/xfs/xfs_buf_item.c b/fs/xfs/xfs_buf_item.c index 240340a4727b..02a80984aa05 100644 --- a/fs/xfs/xfs_buf_item.c +++ b/fs/xfs/xfs_buf_item.c @@ -64,7 +64,7 @@ xfs_buf_item_log_debug( nbytes = last - first + 1; bfset(bip->bli_logged, first, nbytes); for (x = 0; x < nbytes; x++) { - chunk_num = byte >> XFS_BLI_SHIFT; + 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]); @@ -166,7 +166,7 @@ xfs_buf_item_size( * cancel flag in it. */ trace_xfs_buf_item_size_stale(bip); - ASSERT(bip->bli_format.blf_flags & XFS_BLI_CANCEL); + ASSERT(bip->bli_format.blf_flags & XFS_BLF_CANCEL); return 1; } @@ -197,9 +197,9 @@ xfs_buf_item_size( } else if (next_bit != last_bit + 1) { last_bit = next_bit; nvecs++; - } else if (xfs_buf_offset(bp, next_bit * XFS_BLI_CHUNK) != - (xfs_buf_offset(bp, last_bit * XFS_BLI_CHUNK) + - XFS_BLI_CHUNK)) { + } 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 { @@ -254,6 +254,20 @@ xfs_buf_item_format( 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(&bip->bli_item))) + 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 @@ -261,7 +275,7 @@ xfs_buf_item_format( * cancel flag in it. */ trace_xfs_buf_item_format_stale(bip); - ASSERT(bip->bli_format.blf_flags & XFS_BLI_CANCEL); + ASSERT(bip->bli_format.blf_flags & XFS_BLF_CANCEL); bip->bli_format.blf_size = nvecs; return; } @@ -294,28 +308,28 @@ xfs_buf_item_format( * keep counting and scanning. */ if (next_bit == -1) { - buffer_offset = first_bit * XFS_BLI_CHUNK; + buffer_offset = first_bit * XFS_BLF_CHUNK; vecp->i_addr = xfs_buf_offset(bp, buffer_offset); - vecp->i_len = nbits * XFS_BLI_CHUNK; + 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_BLI_CHUNK; + buffer_offset = first_bit * XFS_BLF_CHUNK; vecp->i_addr = xfs_buf_offset(bp, buffer_offset); - vecp->i_len = nbits * XFS_BLI_CHUNK; + 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_BLI_SHIFT) != - (xfs_buf_offset(bp, last_bit << XFS_BLI_SHIFT) + - XFS_BLI_CHUNK)) { - buffer_offset = first_bit * XFS_BLI_CHUNK; + } 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_BLI_CHUNK; + 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 @@ -341,10 +355,15 @@ xfs_buf_item_format( } /* - * This is called to pin the buffer associated with the buf log - * item in memory so it cannot be written out. Simply call bpin() - * on the buffer to do this. + * This is called to pin the buffer associated with the buf log item in memory + * so it cannot be written out. Simply call bpin() on the buffer to do this. + * + * 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( xfs_buf_log_item_t *bip) @@ -356,6 +375,7 @@ xfs_buf_item_pin( ASSERT(atomic_read(&bip->bli_refcount) > 0); ASSERT((bip->bli_flags & XFS_BLI_LOGGED) || (bip->bli_flags & XFS_BLI_STALE)); + atomic_inc(&bip->bli_refcount); trace_xfs_buf_item_pin(bip); xfs_bpin(bp); } @@ -393,7 +413,7 @@ xfs_buf_item_unpin( ASSERT(XFS_BUF_VALUSEMA(bp) <= 0); ASSERT(!(XFS_BUF_ISDELAYWRITE(bp))); ASSERT(XFS_BUF_ISSTALE(bp)); - ASSERT(bip->bli_format.blf_flags & XFS_BLI_CANCEL); + ASSERT(bip->bli_format.blf_flags & XFS_BLF_CANCEL); trace_xfs_buf_item_unpin_stale(bip); /* @@ -489,20 +509,23 @@ xfs_buf_item_trylock( } /* - * 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. + * 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. * - * 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. + * 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( @@ -514,73 +537,54 @@ xfs_buf_item_unlock( bp = bip->bli_buf; - /* - * Clear the buffer's association with this transaction. - */ + /* Clear the buffer's association with this transaction. */ XFS_BUF_SET_FSPRIVATE2(bp, 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. + * 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 = (bip->bli_item.li_flags & XFS_LI_ABORTED) != 0; /* - * 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. + * Before possibly freeing the buf item, determine if we should + * release the buffer at the end of this routine. */ - if (bip->bli_flags & XFS_BLI_STALE) { - bip->bli_flags &= ~XFS_BLI_LOGGED; - trace_xfs_buf_item_unlock_stale(bip); - ASSERT(bip->bli_format.blf_flags & XFS_BLI_CANCEL); - if (!aborted) - return; - } + hold = bip->bli_flags & XFS_BLI_HOLD; + + /* Clear the per transaction state. */ + bip->bli_flags &= ~(XFS_BLI_LOGGED | XFS_BLI_HOLD); /* - * Drop the transaction's reference to the log item if - * it was not logged as part of the transaction. Otherwise - * we'll drop the reference in xfs_buf_item_unpin() when - * the transaction is really through with the buffer. + * 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_LOGGED)) { - atomic_dec(&bip->bli_refcount); - } else { - /* - * Clear the logged flag since this is per - * transaction state. - */ - bip->bli_flags &= ~XFS_BLI_LOGGED; + 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; + } } - /* - * 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; trace_xfs_buf_item_unlock(bip); /* - * If the buf item isn't tracking any data, free it. - * Otherwise, if XFS_BLI_HOLD is set clear it. + * 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)) { + bip->bli_format.blf_map_size)) xfs_buf_item_relse(bp); - } else if (hold) { - bip->bli_flags &= ~XFS_BLI_HOLD; - } + else + atomic_dec(&bip->bli_refcount); - /* - * Release the buffer if XFS_BLI_HOLD was not set. - */ - if (!hold) { + if (!hold) xfs_buf_relse(bp); - } } /* @@ -717,12 +721,12 @@ xfs_buf_item_init( } /* - * chunks is the number of XFS_BLI_CHUNK size pieces + * 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_BLI_CHUNK - 1)) >> XFS_BLI_SHIFT); + 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, @@ -790,8 +794,8 @@ xfs_buf_item_log( /* * Convert byte offsets to bit numbers. */ - first_bit = first >> XFS_BLI_SHIFT; - last_bit = last >> XFS_BLI_SHIFT; + first_bit = first >> XFS_BLF_SHIFT; + last_bit = last >> XFS_BLF_SHIFT; /* * Calculate the total number of bits to be set.