diff options
Diffstat (limited to 'fs/jbd2/commit.c')
-rw-r--r-- | fs/jbd2/commit.c | 184 |
1 files changed, 77 insertions, 107 deletions
diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c index 0f53946..559bec1 100644 --- a/fs/jbd2/commit.c +++ b/fs/jbd2/commit.c @@ -30,15 +30,22 @@ #include <trace/events/jbd2.h> /* - * Default IO end handler for temporary BJ_IO buffer_heads. + * IO end handler for temporary buffer_heads handling writes to the journal. */ static void journal_end_buffer_io_sync(struct buffer_head *bh, int uptodate) { + struct buffer_head *orig_bh = bh->b_private; + BUFFER_TRACE(bh, ""); if (uptodate) set_buffer_uptodate(bh); else clear_buffer_uptodate(bh); + if (orig_bh) { + clear_bit_unlock(BH_Shadow, &orig_bh->b_state); + smp_mb__after_clear_bit(); + wake_up_bit(&orig_bh->b_state, BH_Shadow); + } unlock_buffer(bh); } @@ -85,8 +92,7 @@ nope: __brelse(bh); } -static void jbd2_commit_block_csum_set(journal_t *j, - struct journal_head *descriptor) +static void jbd2_commit_block_csum_set(journal_t *j, struct buffer_head *bh) { struct commit_header *h; __u32 csum; @@ -94,12 +100,11 @@ static void jbd2_commit_block_csum_set(journal_t *j, if (!JBD2_HAS_INCOMPAT_FEATURE(j, JBD2_FEATURE_INCOMPAT_CSUM_V2)) return; - h = (struct commit_header *)(jh2bh(descriptor)->b_data); + h = (struct commit_header *)(bh->b_data); h->h_chksum_type = 0; h->h_chksum_size = 0; h->h_chksum[0] = 0; - csum = jbd2_chksum(j, j->j_csum_seed, jh2bh(descriptor)->b_data, - j->j_blocksize); + csum = jbd2_chksum(j, j->j_csum_seed, bh->b_data, j->j_blocksize); h->h_chksum[0] = cpu_to_be32(csum); } @@ -116,7 +121,6 @@ static int journal_submit_commit_record(journal_t *journal, struct buffer_head **cbh, __u32 crc32_sum) { - struct journal_head *descriptor; struct commit_header *tmp; struct buffer_head *bh; int ret; @@ -127,12 +131,10 @@ static int journal_submit_commit_record(journal_t *journal, if (is_journal_aborted(journal)) return 0; - descriptor = jbd2_journal_get_descriptor_buffer(journal); - if (!descriptor) + bh = jbd2_journal_get_descriptor_buffer(journal); + if (!bh) return 1; - bh = jh2bh(descriptor); - tmp = (struct commit_header *)bh->b_data; tmp->h_magic = cpu_to_be32(JBD2_MAGIC_NUMBER); tmp->h_blocktype = cpu_to_be32(JBD2_COMMIT_BLOCK); @@ -146,9 +148,9 @@ static int journal_submit_commit_record(journal_t *journal, tmp->h_chksum_size = JBD2_CRC32_CHKSUM_SIZE; tmp->h_chksum[0] = cpu_to_be32(crc32_sum); } - jbd2_commit_block_csum_set(journal, descriptor); + jbd2_commit_block_csum_set(journal, bh); - JBUFFER_TRACE(descriptor, "submit commit block"); + BUFFER_TRACE(bh, "submit commit block"); lock_buffer(bh); clear_buffer_dirty(bh); set_buffer_uptodate(bh); @@ -180,7 +182,6 @@ static int journal_wait_on_commit_record(journal_t *journal, if (unlikely(!buffer_uptodate(bh))) ret = -EIO; put_bh(bh); /* One for getblk() */ - jbd2_journal_put_journal_head(bh2jh(bh)); return ret; } @@ -321,7 +322,7 @@ static void write_tag_block(int tag_bytes, journal_block_tag_t *tag, } static void jbd2_descr_block_csum_set(journal_t *j, - struct journal_head *descriptor) + struct buffer_head *bh) { struct jbd2_journal_block_tail *tail; __u32 csum; @@ -329,12 +330,10 @@ static void jbd2_descr_block_csum_set(journal_t *j, if (!JBD2_HAS_INCOMPAT_FEATURE(j, JBD2_FEATURE_INCOMPAT_CSUM_V2)) return; - tail = (struct jbd2_journal_block_tail *) - (jh2bh(descriptor)->b_data + j->j_blocksize - + tail = (struct jbd2_journal_block_tail *)(bh->b_data + j->j_blocksize - sizeof(struct jbd2_journal_block_tail)); tail->t_checksum = 0; - csum = jbd2_chksum(j, j->j_csum_seed, jh2bh(descriptor)->b_data, - j->j_blocksize); + csum = jbd2_chksum(j, j->j_csum_seed, bh->b_data, j->j_blocksize); tail->t_checksum = cpu_to_be32(csum); } @@ -343,20 +342,21 @@ static void jbd2_block_tag_csum_set(journal_t *j, journal_block_tag_t *tag, { struct page *page = bh->b_page; __u8 *addr; - __u32 csum; + __u32 csum32; if (!JBD2_HAS_INCOMPAT_FEATURE(j, JBD2_FEATURE_INCOMPAT_CSUM_V2)) return; sequence = cpu_to_be32(sequence); addr = kmap_atomic(page); - csum = jbd2_chksum(j, j->j_csum_seed, (__u8 *)&sequence, - sizeof(sequence)); - csum = jbd2_chksum(j, csum, addr + offset_in_page(bh->b_data), - bh->b_size); + csum32 = jbd2_chksum(j, j->j_csum_seed, (__u8 *)&sequence, + sizeof(sequence)); + csum32 = jbd2_chksum(j, csum32, addr + offset_in_page(bh->b_data), + bh->b_size); kunmap_atomic(addr); - tag->t_checksum = cpu_to_be32(csum); + /* We only have space to store the lower 16 bits of the crc32c. */ + tag->t_checksum = cpu_to_be16(csum32); } /* * jbd2_journal_commit_transaction @@ -368,7 +368,8 @@ void jbd2_journal_commit_transaction(journal_t *journal) { struct transaction_stats_s stats; transaction_t *commit_transaction; - struct journal_head *jh, *new_jh, *descriptor; + struct journal_head *jh; + struct buffer_head *descriptor; struct buffer_head **wbuf = journal->j_wbuf; int bufs; int flags; @@ -392,6 +393,8 @@ void jbd2_journal_commit_transaction(journal_t *journal) tid_t first_tid; int update_tail; int csum_size = 0; + LIST_HEAD(io_bufs); + LIST_HEAD(log_bufs); if (JBD2_HAS_INCOMPAT_FEATURE(journal, JBD2_FEATURE_INCOMPAT_CSUM_V2)) csum_size = sizeof(struct jbd2_journal_block_tail); @@ -424,13 +427,13 @@ void jbd2_journal_commit_transaction(journal_t *journal) J_ASSERT(journal->j_committing_transaction == NULL); commit_transaction = journal->j_running_transaction; - J_ASSERT(commit_transaction->t_state == T_RUNNING); trace_jbd2_start_commit(journal, commit_transaction); jbd_debug(1, "JBD2: starting commit of transaction %d\n", commit_transaction->t_tid); write_lock(&journal->j_state_lock); + J_ASSERT(commit_transaction->t_state == T_RUNNING); commit_transaction->t_state = T_LOCKED; trace_jbd2_commit_locking(journal, commit_transaction); @@ -520,6 +523,12 @@ void jbd2_journal_commit_transaction(journal_t *journal) */ jbd2_journal_switch_revoke_table(journal); + /* + * Reserved credits cannot be claimed anymore, free them + */ + atomic_sub(atomic_read(&journal->j_reserved_credits), + &commit_transaction->t_outstanding_credits); + trace_jbd2_commit_flushing(journal, commit_transaction); stats.run.rs_flushing = jiffies; stats.run.rs_locked = jbd2_time_diff(stats.run.rs_locked, @@ -533,7 +542,7 @@ void jbd2_journal_commit_transaction(journal_t *journal) wake_up(&journal->j_wait_transaction_locked); write_unlock(&journal->j_state_lock); - jbd_debug(3, "JBD2: commit phase 2\n"); + jbd_debug(3, "JBD2: commit phase 2a\n"); /* * Now start flushing things to disk, in the order they appear @@ -545,10 +554,10 @@ void jbd2_journal_commit_transaction(journal_t *journal) blk_start_plug(&plug); jbd2_journal_write_revoke_records(journal, commit_transaction, - WRITE_SYNC); + &log_bufs, WRITE_SYNC); blk_finish_plug(&plug); - jbd_debug(3, "JBD2: commit phase 2\n"); + jbd_debug(3, "JBD2: commit phase 2b\n"); /* * Way to go: we have now written out all of the data for a @@ -571,8 +580,8 @@ void jbd2_journal_commit_transaction(journal_t *journal) atomic_read(&commit_transaction->t_outstanding_credits)); err = 0; - descriptor = NULL; bufs = 0; + descriptor = NULL; blk_start_plug(&plug); while (commit_transaction->t_buffers) { @@ -604,8 +613,6 @@ void jbd2_journal_commit_transaction(journal_t *journal) record the metadata buffer. */ if (!descriptor) { - struct buffer_head *bh; - J_ASSERT (bufs == 0); jbd_debug(4, "JBD2: get descriptor\n"); @@ -616,26 +623,26 @@ void jbd2_journal_commit_transaction(journal_t *journal) continue; } - bh = jh2bh(descriptor); jbd_debug(4, "JBD2: got buffer %llu (%p)\n", - (unsigned long long)bh->b_blocknr, bh->b_data); - header = (journal_header_t *)&bh->b_data[0]; + (unsigned long long)descriptor->b_blocknr, + descriptor->b_data); + header = (journal_header_t *)descriptor->b_data; header->h_magic = cpu_to_be32(JBD2_MAGIC_NUMBER); header->h_blocktype = cpu_to_be32(JBD2_DESCRIPTOR_BLOCK); header->h_sequence = cpu_to_be32(commit_transaction->t_tid); - tagp = &bh->b_data[sizeof(journal_header_t)]; - space_left = bh->b_size - sizeof(journal_header_t); + tagp = &descriptor->b_data[sizeof(journal_header_t)]; + space_left = descriptor->b_size - + sizeof(journal_header_t); first_tag = 1; - set_buffer_jwrite(bh); - set_buffer_dirty(bh); - wbuf[bufs++] = bh; + set_buffer_jwrite(descriptor); + set_buffer_dirty(descriptor); + wbuf[bufs++] = descriptor; /* Record it so that we can wait for IO completion later */ - BUFFER_TRACE(bh, "ph3: file as descriptor"); - jbd2_journal_file_buffer(descriptor, commit_transaction, - BJ_LogCtl); + BUFFER_TRACE(descriptor, "ph3: file as descriptor"); + jbd2_file_log_bh(&log_bufs, descriptor); } /* Where is the buffer to be written? */ @@ -658,29 +665,22 @@ void jbd2_journal_commit_transaction(journal_t *journal) /* Bump b_count to prevent truncate from stumbling over the shadowed buffer! @@@ This can go if we ever get - rid of the BJ_IO/BJ_Shadow pairing of buffers. */ + rid of the shadow pairing of buffers. */ atomic_inc(&jh2bh(jh)->b_count); - /* Make a temporary IO buffer with which to write it out - (this will requeue both the metadata buffer and the - temporary IO buffer). new_bh goes on BJ_IO*/ - - set_bit(BH_JWrite, &jh2bh(jh)->b_state); /* - * akpm: jbd2_journal_write_metadata_buffer() sets - * new_bh->b_transaction to commit_transaction. - * We need to clean this up before we release new_bh - * (which is of type BJ_IO) + * Make a temporary IO buffer with which to write it out + * (this will requeue the metadata buffer to BJ_Shadow). */ + set_bit(BH_JWrite, &jh2bh(jh)->b_state); JBUFFER_TRACE(jh, "ph3: write metadata"); flags = jbd2_journal_write_metadata_buffer(commit_transaction, - jh, &new_jh, blocknr); + jh, &wbuf[bufs], blocknr); if (flags < 0) { jbd2_journal_abort(journal, flags); continue; } - set_bit(BH_JWrite, &jh2bh(new_jh)->b_state); - wbuf[bufs++] = jh2bh(new_jh); + jbd2_file_log_bh(&io_bufs, wbuf[bufs]); /* Record the new block's tag in the current descriptor buffer */ @@ -694,10 +694,11 @@ void jbd2_journal_commit_transaction(journal_t *journal) tag = (journal_block_tag_t *) tagp; write_tag_block(tag_bytes, tag, jh2bh(jh)->b_blocknr); tag->t_flags = cpu_to_be16(tag_flag); - jbd2_block_tag_csum_set(journal, tag, jh2bh(new_jh), + jbd2_block_tag_csum_set(journal, tag, wbuf[bufs], commit_transaction->t_tid); tagp += tag_bytes; space_left -= tag_bytes; + bufs++; if (first_tag) { memcpy (tagp, journal->j_uuid, 16); @@ -809,7 +810,7 @@ start_journal_io: the log. Before we can commit it, wait for the IO so far to complete. Control buffers being written are on the transaction's t_log_list queue, and metadata buffers are on - the t_iobuf_list queue. + the io_bufs list. Wait for the buffers in reverse order. That way we are less likely to be woken up until all IOs have completed, and @@ -818,47 +819,33 @@ start_journal_io: jbd_debug(3, "JBD2: commit phase 3\n"); - /* - * akpm: these are BJ_IO, and j_list_lock is not needed. - * See __journal_try_to_free_buffer. - */ -wait_for_iobuf: - while (commit_transaction->t_iobuf_list != NULL) { - struct buffer_head *bh; + while (!list_empty(&io_bufs)) { + struct buffer_head *bh = list_entry(io_bufs.prev, + struct buffer_head, + b_assoc_buffers); - jh = commit_transaction->t_iobuf_list->b_tprev; - bh = jh2bh(jh); - if (buffer_locked(bh)) { - wait_on_buffer(bh); - goto wait_for_iobuf; - } - if (cond_resched()) - goto wait_for_iobuf; + wait_on_buffer(bh); + cond_resched(); if (unlikely(!buffer_uptodate(bh))) err = -EIO; - - clear_buffer_jwrite(bh); - - JBUFFER_TRACE(jh, "ph4: unfile after journal write"); - jbd2_journal_unfile_buffer(journal, jh); + jbd2_unfile_log_bh(bh); /* - * ->t_iobuf_list should contain only dummy buffer_heads - * which were created by jbd2_journal_write_metadata_buffer(). + * The list contains temporary buffer heads created by + * jbd2_journal_write_metadata_buffer(). */ BUFFER_TRACE(bh, "dumping temporary bh"); - jbd2_journal_put_journal_head(jh); __brelse(bh); J_ASSERT_BH(bh, atomic_read(&bh->b_count) == 0); free_buffer_head(bh); - /* We also have to unlock and free the corresponding - shadowed buffer */ + /* We also have to refile the corresponding shadowed buffer */ jh = commit_transaction->t_shadow_list->b_tprev; bh = jh2bh(jh); - clear_bit(BH_JWrite, &bh->b_state); + clear_buffer_jwrite(bh); J_ASSERT_BH(bh, buffer_jbddirty(bh)); + J_ASSERT_BH(bh, !buffer_shadow(bh)); /* The metadata is now released for reuse, but we need to remember it against this transaction so that when @@ -866,14 +853,6 @@ wait_for_iobuf: required. */ JBUFFER_TRACE(jh, "file as BJ_Forget"); jbd2_journal_file_buffer(jh, commit_transaction, BJ_Forget); - /* - * Wake up any transactions which were waiting for this IO to - * complete. The barrier must be here so that changes by - * jbd2_journal_file_buffer() take effect before wake_up_bit() - * does the waitqueue check. - */ - smp_mb(); - wake_up_bit(&bh->b_state, BH_Unshadow); JBUFFER_TRACE(jh, "brelse shadowed buffer"); __brelse(bh); } @@ -883,26 +862,19 @@ wait_for_iobuf: jbd_debug(3, "JBD2: commit phase 4\n"); /* Here we wait for the revoke record and descriptor record buffers */ - wait_for_ctlbuf: - while (commit_transaction->t_log_list != NULL) { + while (!list_empty(&log_bufs)) { struct buffer_head *bh; - jh = commit_transaction->t_log_list->b_tprev; - bh = jh2bh(jh); - if (buffer_locked(bh)) { - wait_on_buffer(bh); - goto wait_for_ctlbuf; - } - if (cond_resched()) - goto wait_for_ctlbuf; + bh = list_entry(log_bufs.prev, struct buffer_head, b_assoc_buffers); + wait_on_buffer(bh); + cond_resched(); if (unlikely(!buffer_uptodate(bh))) err = -EIO; BUFFER_TRACE(bh, "ph5: control buffer writeout done: unfile"); clear_buffer_jwrite(bh); - jbd2_journal_unfile_buffer(journal, jh); - jbd2_journal_put_journal_head(jh); + jbd2_unfile_log_bh(bh); __brelse(bh); /* One for getblk */ /* AKPM: bforget here */ } @@ -952,9 +924,7 @@ wait_for_iobuf: J_ASSERT(list_empty(&commit_transaction->t_inode_list)); J_ASSERT(commit_transaction->t_buffers == NULL); J_ASSERT(commit_transaction->t_checkpoint_list == NULL); - J_ASSERT(commit_transaction->t_iobuf_list == NULL); J_ASSERT(commit_transaction->t_shadow_list == NULL); - J_ASSERT(commit_transaction->t_log_list == NULL); restart_loop: /* |