| /* |
| * Copyright (c) 2000-2006 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_shared.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_da_format.h" |
| #include "xfs_da_btree.h" |
| #include "xfs_inode.h" |
| #include "xfs_trans.h" |
| #include "xfs_log.h" |
| #include "xfs_log_priv.h" |
| #include "xfs_log_recover.h" |
| #include "xfs_inode_item.h" |
| #include "xfs_extfree_item.h" |
| #include "xfs_trans_priv.h" |
| #include "xfs_alloc.h" |
| #include "xfs_ialloc.h" |
| #include "xfs_quota.h" |
| #include "xfs_cksum.h" |
| #include "xfs_trace.h" |
| #include "xfs_icache.h" |
| #include "xfs_bmap_btree.h" |
| #include "xfs_error.h" |
| #include "xfs_dir2.h" |
| #include "xfs_rmap_item.h" |
| #include "xfs_buf_item.h" |
| #include "xfs_refcount_item.h" |
| #include "xfs_bmap_item.h" |
| |
| #define BLK_AVG(blk1, blk2) ((blk1+blk2) >> 1) |
| |
| STATIC int |
| xlog_find_zeroed( |
| struct xlog *, |
| xfs_daddr_t *); |
| STATIC int |
| xlog_clear_stale_blocks( |
| struct xlog *, |
| xfs_lsn_t); |
| #if defined(DEBUG) |
| STATIC void |
| xlog_recover_check_summary( |
| struct xlog *); |
| #else |
| #define xlog_recover_check_summary(log) |
| #endif |
| STATIC int |
| xlog_do_recovery_pass( |
| struct xlog *, xfs_daddr_t, xfs_daddr_t, int, xfs_daddr_t *); |
| |
| /* |
| * This structure is used during recovery to record the buf log items which |
| * have been canceled and should not be replayed. |
| */ |
| struct xfs_buf_cancel { |
| xfs_daddr_t bc_blkno; |
| uint bc_len; |
| int bc_refcount; |
| struct list_head bc_list; |
| }; |
| |
| /* |
| * Sector aligned buffer routines for buffer create/read/write/access |
| */ |
| |
| /* |
| * Verify the given count of basic blocks is valid number of blocks |
| * to specify for an operation involving the given XFS log buffer. |
| * Returns nonzero if the count is valid, 0 otherwise. |
| */ |
| |
| static inline int |
| xlog_buf_bbcount_valid( |
| struct xlog *log, |
| int bbcount) |
| { |
| return bbcount > 0 && bbcount <= log->l_logBBsize; |
| } |
| |
| /* |
| * Allocate a buffer to hold log data. The buffer needs to be able |
| * to map to a range of nbblks basic blocks at any valid (basic |
| * block) offset within the log. |
| */ |
| STATIC xfs_buf_t * |
| xlog_get_bp( |
| struct xlog *log, |
| int nbblks) |
| { |
| struct xfs_buf *bp; |
| |
| if (!xlog_buf_bbcount_valid(log, nbblks)) { |
| xfs_warn(log->l_mp, "Invalid block length (0x%x) for buffer", |
| nbblks); |
| XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_HIGH, log->l_mp); |
| return NULL; |
| } |
| |
| /* |
| * We do log I/O in units of log sectors (a power-of-2 |
| * multiple of the basic block size), so we round up the |
| * requested size to accommodate the basic blocks required |
| * for complete log sectors. |
| * |
| * In addition, the buffer may be used for a non-sector- |
| * aligned block offset, in which case an I/O of the |
| * requested size could extend beyond the end of the |
| * buffer. If the requested size is only 1 basic block it |
| * will never straddle a sector boundary, so this won't be |
| * an issue. Nor will this be a problem if the log I/O is |
| * done in basic blocks (sector size 1). But otherwise we |
| * extend the buffer by one extra log sector to ensure |
| * there's space to accommodate this possibility. |
| */ |
| if (nbblks > 1 && log->l_sectBBsize > 1) |
| nbblks += log->l_sectBBsize; |
| nbblks = round_up(nbblks, log->l_sectBBsize); |
| |
| bp = xfs_buf_get_uncached(log->l_mp->m_logdev_targp, nbblks, 0); |
| if (bp) |
| xfs_buf_unlock(bp); |
| return bp; |
| } |
| |
| STATIC void |
| xlog_put_bp( |
| xfs_buf_t *bp) |
| { |
| xfs_buf_free(bp); |
| } |
| |
| /* |
| * Return the address of the start of the given block number's data |
| * in a log buffer. The buffer covers a log sector-aligned region. |
| */ |
| STATIC char * |
| xlog_align( |
| struct xlog *log, |
| xfs_daddr_t blk_no, |
| int nbblks, |
| struct xfs_buf *bp) |
| { |
| xfs_daddr_t offset = blk_no & ((xfs_daddr_t)log->l_sectBBsize - 1); |
| |
| ASSERT(offset + nbblks <= bp->b_length); |
| return bp->b_addr + BBTOB(offset); |
| } |
| |
| |
| /* |
| * nbblks should be uint, but oh well. Just want to catch that 32-bit length. |
| */ |
| STATIC int |
| xlog_bread_noalign( |
| struct xlog *log, |
| xfs_daddr_t blk_no, |
| int nbblks, |
| struct xfs_buf *bp) |
| { |
| int error; |
| |
| if (!xlog_buf_bbcount_valid(log, nbblks)) { |
| xfs_warn(log->l_mp, "Invalid block length (0x%x) for buffer", |
| nbblks); |
| XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_HIGH, log->l_mp); |
| return -EFSCORRUPTED; |
| } |
| |
| blk_no = round_down(blk_no, log->l_sectBBsize); |
| nbblks = round_up(nbblks, log->l_sectBBsize); |
| |
| ASSERT(nbblks > 0); |
| ASSERT(nbblks <= bp->b_length); |
| |
| XFS_BUF_SET_ADDR(bp, log->l_logBBstart + blk_no); |
| bp->b_flags |= XBF_READ; |
| bp->b_io_length = nbblks; |
| bp->b_error = 0; |
| |
| error = xfs_buf_submit_wait(bp); |
| if (error && !XFS_FORCED_SHUTDOWN(log->l_mp)) |
| xfs_buf_ioerror_alert(bp, __func__); |
| return error; |
| } |
| |
| STATIC int |
| xlog_bread( |
| struct xlog *log, |
| xfs_daddr_t blk_no, |
| int nbblks, |
| struct xfs_buf *bp, |
| char **offset) |
| { |
| int error; |
| |
| error = xlog_bread_noalign(log, blk_no, nbblks, bp); |
| if (error) |
| return error; |
| |
| *offset = xlog_align(log, blk_no, nbblks, bp); |
| return 0; |
| } |
| |
| /* |
| * Read at an offset into the buffer. Returns with the buffer in it's original |
| * state regardless of the result of the read. |
| */ |
| STATIC int |
| xlog_bread_offset( |
| struct xlog *log, |
| xfs_daddr_t blk_no, /* block to read from */ |
| int nbblks, /* blocks to read */ |
| struct xfs_buf *bp, |
| char *offset) |
| { |
| char *orig_offset = bp->b_addr; |
| int orig_len = BBTOB(bp->b_length); |
| int error, error2; |
| |
| error = xfs_buf_associate_memory(bp, offset, BBTOB(nbblks)); |
| if (error) |
| return error; |
| |
| error = xlog_bread_noalign(log, blk_no, nbblks, bp); |
| |
| /* must reset buffer pointer even on error */ |
| error2 = xfs_buf_associate_memory(bp, orig_offset, orig_len); |
| if (error) |
| return error; |
| return error2; |
| } |
| |
| /* |
| * Write out the buffer at the given block for the given number of blocks. |
| * The buffer is kept locked across the write and is returned locked. |
| * This can only be used for synchronous log writes. |
| */ |
| STATIC int |
| xlog_bwrite( |
| struct xlog *log, |
| xfs_daddr_t blk_no, |
| int nbblks, |
| struct xfs_buf *bp) |
| { |
| int error; |
| |
| if (!xlog_buf_bbcount_valid(log, nbblks)) { |
| xfs_warn(log->l_mp, "Invalid block length (0x%x) for buffer", |
| nbblks); |
| XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_HIGH, log->l_mp); |
| return -EFSCORRUPTED; |
| } |
| |
| blk_no = round_down(blk_no, log->l_sectBBsize); |
| nbblks = round_up(nbblks, log->l_sectBBsize); |
| |
| ASSERT(nbblks > 0); |
| ASSERT(nbblks <= bp->b_length); |
| |
| XFS_BUF_SET_ADDR(bp, log->l_logBBstart + blk_no); |
| xfs_buf_hold(bp); |
| xfs_buf_lock(bp); |
| bp->b_io_length = nbblks; |
| bp->b_error = 0; |
| |
| error = xfs_bwrite(bp); |
| if (error) |
| xfs_buf_ioerror_alert(bp, __func__); |
| xfs_buf_relse(bp); |
| return error; |
| } |
| |
| #ifdef DEBUG |
| /* |
| * dump debug superblock and log record information |
| */ |
| STATIC void |
| xlog_header_check_dump( |
| xfs_mount_t *mp, |
| xlog_rec_header_t *head) |
| { |
| xfs_debug(mp, "%s: SB : uuid = %pU, fmt = %d", |
| __func__, &mp->m_sb.sb_uuid, XLOG_FMT); |
| xfs_debug(mp, " log : uuid = %pU, fmt = %d", |
| &head->h_fs_uuid, be32_to_cpu(head->h_fmt)); |
| } |
| #else |
| #define xlog_header_check_dump(mp, head) |
| #endif |
| |
| /* |
| * check log record header for recovery |
| */ |
| STATIC int |
| xlog_header_check_recover( |
| xfs_mount_t *mp, |
| xlog_rec_header_t *head) |
| { |
| ASSERT(head->h_magicno == cpu_to_be32(XLOG_HEADER_MAGIC_NUM)); |
| |
| /* |
| * IRIX doesn't write the h_fmt field and leaves it zeroed |
| * (XLOG_FMT_UNKNOWN). This stops us from trying to recover |
| * a dirty log created in IRIX. |
| */ |
| if (unlikely(head->h_fmt != cpu_to_be32(XLOG_FMT))) { |
| xfs_warn(mp, |
| "dirty log written in incompatible format - can't recover"); |
| xlog_header_check_dump(mp, head); |
| XFS_ERROR_REPORT("xlog_header_check_recover(1)", |
| XFS_ERRLEVEL_HIGH, mp); |
| return -EFSCORRUPTED; |
| } else if (unlikely(!uuid_equal(&mp->m_sb.sb_uuid, &head->h_fs_uuid))) { |
| xfs_warn(mp, |
| "dirty log entry has mismatched uuid - can't recover"); |
| xlog_header_check_dump(mp, head); |
| XFS_ERROR_REPORT("xlog_header_check_recover(2)", |
| XFS_ERRLEVEL_HIGH, mp); |
| return -EFSCORRUPTED; |
| } |
| return 0; |
| } |
| |
| /* |
| * read the head block of the log and check the header |
| */ |
| STATIC int |
| xlog_header_check_mount( |
| xfs_mount_t *mp, |
| xlog_rec_header_t *head) |
| { |
| ASSERT(head->h_magicno == cpu_to_be32(XLOG_HEADER_MAGIC_NUM)); |
| |
| if (uuid_is_null(&head->h_fs_uuid)) { |
| /* |
| * IRIX doesn't write the h_fs_uuid or h_fmt fields. If |
| * h_fs_uuid is null, we assume this log was last mounted |
| * by IRIX and continue. |
| */ |
| xfs_warn(mp, "null uuid in log - IRIX style log"); |
| } else if (unlikely(!uuid_equal(&mp->m_sb.sb_uuid, &head->h_fs_uuid))) { |
| xfs_warn(mp, "log has mismatched uuid - can't recover"); |
| xlog_header_check_dump(mp, head); |
| XFS_ERROR_REPORT("xlog_header_check_mount", |
| XFS_ERRLEVEL_HIGH, mp); |
| return -EFSCORRUPTED; |
| } |
| return 0; |
| } |
| |
| STATIC void |
| xlog_recover_iodone( |
| struct xfs_buf *bp) |
| { |
| if (bp->b_error) { |
| /* |
| * We're not going to bother about retrying |
| * this during recovery. One strike! |
| */ |
| if (!XFS_FORCED_SHUTDOWN(bp->b_target->bt_mount)) { |
| xfs_buf_ioerror_alert(bp, __func__); |
| xfs_force_shutdown(bp->b_target->bt_mount, |
| SHUTDOWN_META_IO_ERROR); |
| } |
| } |
| |
| /* |
| * On v5 supers, a bli could be attached to update the metadata LSN. |
| * Clean it up. |
| */ |
| if (bp->b_fspriv) |
| xfs_buf_item_relse(bp); |
| ASSERT(bp->b_fspriv == NULL); |
| |
| bp->b_iodone = NULL; |
| xfs_buf_ioend(bp); |
| } |
| |
| /* |
| * This routine finds (to an approximation) the first block in the physical |
| * log which contains the given cycle. It uses a binary search algorithm. |
| * Note that the algorithm can not be perfect because the disk will not |
| * necessarily be perfect. |
| */ |
| STATIC int |
| xlog_find_cycle_start( |
| struct xlog *log, |
| struct xfs_buf *bp, |
| xfs_daddr_t first_blk, |
| xfs_daddr_t *last_blk, |
| uint cycle) |
| { |
| char *offset; |
| xfs_daddr_t mid_blk; |
| xfs_daddr_t end_blk; |
| uint mid_cycle; |
| int error; |
| |
| end_blk = *last_blk; |
| mid_blk = BLK_AVG(first_blk, end_blk); |
| while (mid_blk != first_blk && mid_blk != end_blk) { |
| error = xlog_bread(log, mid_blk, 1, bp, &offset); |
| if (error) |
| return error; |
| mid_cycle = xlog_get_cycle(offset); |
| if (mid_cycle == cycle) |
| end_blk = mid_blk; /* last_half_cycle == mid_cycle */ |
| else |
| first_blk = mid_blk; /* first_half_cycle == mid_cycle */ |
| mid_blk = BLK_AVG(first_blk, end_blk); |
| } |
| ASSERT((mid_blk == first_blk && mid_blk+1 == end_blk) || |
| (mid_blk == end_blk && mid_blk-1 == first_blk)); |
| |
| *last_blk = end_blk; |
| |
| return 0; |
| } |
| |
| /* |
| * Check that a range of blocks does not contain stop_on_cycle_no. |
| * Fill in *new_blk with the block offset where such a block is |
| * found, or with -1 (an invalid block number) if there is no such |
| * block in the range. The scan needs to occur from front to back |
| * and the pointer into the region must be updated since a later |
| * routine will need to perform another test. |
| */ |
| STATIC int |
| xlog_find_verify_cycle( |
| struct xlog *log, |
| xfs_daddr_t start_blk, |
| int nbblks, |
| uint stop_on_cycle_no, |
| xfs_daddr_t *new_blk) |
| { |
| xfs_daddr_t i, j; |
| uint cycle; |
| xfs_buf_t *bp; |
| xfs_daddr_t bufblks; |
| char *buf = NULL; |
| int error = 0; |
| |
| /* |
| * Greedily allocate a buffer big enough to handle the full |
| * range of basic blocks we'll be examining. If that fails, |
| * try a smaller size. We need to be able to read at least |
| * a log sector, or we're out of luck. |
| */ |
| bufblks = 1 << ffs(nbblks); |
| while (bufblks > log->l_logBBsize) |
| bufblks >>= 1; |
| while (!(bp = xlog_get_bp(log, bufblks))) { |
| bufblks >>= 1; |
| if (bufblks < log->l_sectBBsize) |
| return -ENOMEM; |
| } |
| |
| for (i = start_blk; i < start_blk + nbblks; i += bufblks) { |
| int bcount; |
| |
| bcount = min(bufblks, (start_blk + nbblks - i)); |
| |
| error = xlog_bread(log, i, bcount, bp, &buf); |
| if (error) |
| goto out; |
| |
| for (j = 0; j < bcount; j++) { |
| cycle = xlog_get_cycle(buf); |
| if (cycle == stop_on_cycle_no) { |
| *new_blk = i+j; |
| goto out; |
| } |
| |
| buf += BBSIZE; |
| } |
| } |
| |
| *new_blk = -1; |
| |
| out: |
| xlog_put_bp(bp); |
| return error; |
| } |
| |
| /* |
| * Potentially backup over partial log record write. |
| * |
| * In the typical case, last_blk is the number of the block directly after |
| * a good log record. Therefore, we subtract one to get the block number |
| * of the last block in the given buffer. extra_bblks contains the number |
| * of blocks we would have read on a previous read. This happens when the |
| * last log record is split over the end of the physical log. |
| * |
| * extra_bblks is the number of blocks potentially verified on a previous |
| * call to this routine. |
| */ |
| STATIC int |
| xlog_find_verify_log_record( |
| struct xlog *log, |
| xfs_daddr_t start_blk, |
| xfs_daddr_t *last_blk, |
| int extra_bblks) |
| { |
| xfs_daddr_t i; |
| xfs_buf_t *bp; |
| char *offset = NULL; |
| xlog_rec_header_t *head = NULL; |
| int error = 0; |
| int smallmem = 0; |
| int num_blks = *last_blk - start_blk; |
| int xhdrs; |
| |
| ASSERT(start_blk != 0 || *last_blk != start_blk); |
| |
| if (!(bp = xlog_get_bp(log, num_blks))) { |
| if (!(bp = xlog_get_bp(log, 1))) |
| return -ENOMEM; |
| smallmem = 1; |
| } else { |
| error = xlog_bread(log, start_blk, num_blks, bp, &offset); |
| if (error) |
| goto out; |
| offset += ((num_blks - 1) << BBSHIFT); |
| } |
| |
| for (i = (*last_blk) - 1; i >= 0; i--) { |
| if (i < start_blk) { |
| /* valid log record not found */ |
| xfs_warn(log->l_mp, |
| "Log inconsistent (didn't find previous header)"); |
| ASSERT(0); |
| error = -EIO; |
| goto out; |
| } |
| |
| if (smallmem) { |
| error = xlog_bread(log, i, 1, bp, &offset); |
| if (error) |
| goto out; |
| } |
| |
| head = (xlog_rec_header_t *)offset; |
| |
| if (head->h_magicno == cpu_to_be32(XLOG_HEADER_MAGIC_NUM)) |
| break; |
| |
| if (!smallmem) |
| offset -= BBSIZE; |
| } |
| |
| /* |
| * We hit the beginning of the physical log & still no header. Return |
| * to caller. If caller can handle a return of -1, then this routine |
| * will be called again for the end of the physical log. |
| */ |
| if (i == -1) { |
| error = 1; |
| goto out; |
| } |
| |
| /* |
| * We have the final block of the good log (the first block |
| * of the log record _before_ the head. So we check the uuid. |
| */ |
| if ((error = xlog_header_check_mount(log->l_mp, head))) |
| goto out; |
| |
| /* |
| * We may have found a log record header before we expected one. |
| * last_blk will be the 1st block # with a given cycle #. We may end |
| * up reading an entire log record. In this case, we don't want to |
| * reset last_blk. Only when last_blk points in the middle of a log |
| * record do we update last_blk. |
| */ |
| if (xfs_sb_version_haslogv2(&log->l_mp->m_sb)) { |
| uint h_size = be32_to_cpu(head->h_size); |
| |
| xhdrs = h_size / XLOG_HEADER_CYCLE_SIZE; |
| if (h_size % XLOG_HEADER_CYCLE_SIZE) |
| xhdrs++; |
| } else { |
| xhdrs = 1; |
| } |
| |
| if (*last_blk - i + extra_bblks != |
| BTOBB(be32_to_cpu(head->h_len)) + xhdrs) |
| *last_blk = i; |
| |
| out: |
| xlog_put_bp(bp); |
| return error; |
| } |
| |
| /* |
| * Head is defined to be the point of the log where the next log write |
| * could go. This means that incomplete LR writes at the end are |
| * eliminated when calculating the head. We aren't guaranteed that previous |
| * LR have complete transactions. We only know that a cycle number of |
| * current cycle number -1 won't be present in the log if we start writing |
| * from our current block number. |
| * |
| * last_blk contains the block number of the first block with a given |
| * cycle number. |
| * |
| * Return: zero if normal, non-zero if error. |
| */ |
| STATIC int |
| xlog_find_head( |
| struct xlog *log, |
| xfs_daddr_t *return_head_blk) |
| { |
| xfs_buf_t *bp; |
| char *offset; |
| xfs_daddr_t new_blk, first_blk, start_blk, last_blk, head_blk; |
| int num_scan_bblks; |
| uint first_half_cycle, last_half_cycle; |
| uint stop_on_cycle; |
| int error, log_bbnum = log->l_logBBsize; |
| |
| /* Is the end of the log device zeroed? */ |
| error = xlog_find_zeroed(log, &first_blk); |
| if (error < 0) { |
| xfs_warn(log->l_mp, "empty log check failed"); |
| return error; |
| } |
| if (error == 1) { |
| *return_head_blk = first_blk; |
| |
| /* Is the whole lot zeroed? */ |
| if (!first_blk) { |
| /* Linux XFS shouldn't generate totally zeroed logs - |
| * mkfs etc write a dummy unmount record to a fresh |
| * log so we can store the uuid in there |
| */ |
| xfs_warn(log->l_mp, "totally zeroed log"); |
| } |
| |
| return 0; |
| } |
| |
| first_blk = 0; /* get cycle # of 1st block */ |
| bp = xlog_get_bp(log, 1); |
| if (!bp) |
| return -ENOMEM; |
| |
| error = xlog_bread(log, 0, 1, bp, &offset); |
| if (error) |
| goto bp_err; |
| |
| first_half_cycle = xlog_get_cycle(offset); |
| |
| last_blk = head_blk = log_bbnum - 1; /* get cycle # of last block */ |
| error = xlog_bread(log, last_blk, 1, bp, &offset); |
| if (error) |
| goto bp_err; |
| |
| last_half_cycle = xlog_get_cycle(offset); |
| ASSERT(last_half_cycle != 0); |
| |
| /* |
| * If the 1st half cycle number is equal to the last half cycle number, |
| * then the entire log is stamped with the same cycle number. In this |
| * case, head_blk can't be set to zero (which makes sense). The below |
| * math doesn't work out properly with head_blk equal to zero. Instead, |
| * we set it to log_bbnum which is an invalid block number, but this |
| * value makes the math correct. If head_blk doesn't changed through |
| * all the tests below, *head_blk is set to zero at the very end rather |
| * than log_bbnum. In a sense, log_bbnum and zero are the same block |
| * in a circular file. |
| */ |
| if (first_half_cycle == last_half_cycle) { |
| /* |
| * In this case we believe that the entire log should have |
| * cycle number last_half_cycle. We need to scan backwards |
| * from the end verifying that there are no holes still |
| * containing last_half_cycle - 1. If we find such a hole, |
| * then the start of that hole will be the new head. The |
| * simple case looks like |
| * x | x ... | x - 1 | x |
| * Another case that fits this picture would be |
| * x | x + 1 | x ... | x |
| * In this case the head really is somewhere at the end of the |
| * log, as one of the latest writes at the beginning was |
| * incomplete. |
| * One more case is |
| * x | x + 1 | x ... | x - 1 | x |
| * This is really the combination of the above two cases, and |
| * the head has to end up at the start of the x-1 hole at the |
| * end of the log. |
| * |
| * In the 256k log case, we will read from the beginning to the |
| * end of the log and search for cycle numbers equal to x-1. |
| * We don't worry about the x+1 blocks that we encounter, |
| * because we know that they cannot be the head since the log |
| * started with x. |
| */ |
| head_blk = log_bbnum; |
| stop_on_cycle = last_half_cycle - 1; |
| } else { |
| /* |
| * In this case we want to find the first block with cycle |
| * number matching last_half_cycle. We expect the log to be |
| * some variation on |
| * x + 1 ... | x ... | x |
| * The first block with cycle number x (last_half_cycle) will |
| * be where the new head belongs. First we do a binary search |
| * for the first occurrence of last_half_cycle. The binary |
| * search may not be totally accurate, so then we scan back |
| * from there looking for occurrences of last_half_cycle before |
| * us. If that backwards scan wraps around the beginning of |
| * the log, then we look for occurrences of last_half_cycle - 1 |
| * at the end of the log. The cases we're looking for look |
| * like |
| * v binary search stopped here |
| * x + 1 ... | x | x + 1 | x ... | x |
| * ^ but we want to locate this spot |
| * or |
| * <---------> less than scan distance |
| * x + 1 ... | x ... | x - 1 | x |
| * ^ we want to locate this spot |
| */ |
| stop_on_cycle = last_half_cycle; |
| if ((error = xlog_find_cycle_start(log, bp, first_blk, |
| &head_blk, last_half_cycle))) |
| goto bp_err; |
| } |
| |
| /* |
| * Now validate the answer. Scan back some number of maximum possible |
| * blocks and make sure each one has the expected cycle number. The |
| * maximum is determined by the total possible amount of buffering |
| * in the in-core log. The following number can be made tighter if |
| * we actually look at the block size of the filesystem. |
| */ |
| num_scan_bblks = XLOG_TOTAL_REC_SHIFT(log); |
| if (head_blk >= num_scan_bblks) { |
| /* |
| * We are guaranteed that the entire check can be performed |
| * in one buffer. |
| */ |
| start_blk = head_blk - num_scan_bblks; |
| if ((error = xlog_find_verify_cycle(log, |
| start_blk, num_scan_bblks, |
| stop_on_cycle, &new_blk))) |
| goto bp_err; |
| if (new_blk != -1) |
| head_blk = new_blk; |
| } else { /* need to read 2 parts of log */ |
| /* |
| * We are going to scan backwards in the log in two parts. |
| * First we scan the physical end of the log. In this part |
| * of the log, we are looking for blocks with cycle number |
| * last_half_cycle - 1. |
| * If we find one, then we know that the log starts there, as |
| * we've found a hole that didn't get written in going around |
| * the end of the physical log. The simple case for this is |
| * x + 1 ... | x ... | x - 1 | x |
| * <---------> less than scan distance |
| * If all of the blocks at the end of the log have cycle number |
| * last_half_cycle, then we check the blocks at the start of |
| * the log looking for occurrences of last_half_cycle. If we |
| * find one, then our current estimate for the location of the |
| * first occurrence of last_half_cycle is wrong and we move |
| * back to the hole we've found. This case looks like |
| * x + 1 ... | x | x + 1 | x ... |
| * ^ binary search stopped here |
| * Another case we need to handle that only occurs in 256k |
| * logs is |
| * x + 1 ... | x ... | x+1 | x ... |
| * ^ binary search stops here |
| * In a 256k log, the scan at the end of the log will see the |
| * x + 1 blocks. We need to skip past those since that is |
| * certainly not the head of the log. By searching for |
| * last_half_cycle-1 we accomplish that. |
| */ |
| ASSERT(head_blk <= INT_MAX && |
| (xfs_daddr_t) num_scan_bblks >= head_blk); |
| start_blk = log_bbnum - (num_scan_bblks - head_blk); |
| if ((error = xlog_find_verify_cycle(log, start_blk, |
| num_scan_bblks - (int)head_blk, |
| (stop_on_cycle - 1), &new_blk))) |
| goto bp_err; |
| if (new_blk != -1) { |
| head_blk = new_blk; |
| goto validate_head; |
| } |
| |
| /* |
| * Scan beginning of log now. The last part of the physical |
| * log is good. This scan needs to verify that it doesn't find |
| * the last_half_cycle. |
| */ |
| start_blk = 0; |
| ASSERT(head_blk <= INT_MAX); |
| if ((error = xlog_find_verify_cycle(log, |
| start_blk, (int)head_blk, |
| stop_on_cycle, &new_blk))) |
| goto bp_err; |
| if (new_blk != -1) |
| head_blk = new_blk; |
| } |
| |
| validate_head: |
| /* |
| * Now we need to make sure head_blk is not pointing to a block in |
| * the middle of a log record. |
| */ |
| num_scan_bblks = XLOG_REC_SHIFT(log); |
| if (head_blk >= num_scan_bblks) { |
| start_blk = head_blk - num_scan_bblks; /* don't read head_blk */ |
| |
| /* start ptr at last block ptr before head_blk */ |
| error = xlog_find_verify_log_record(log, start_blk, &head_blk, 0); |
| if (error == 1) |
| error = -EIO; |
| if (error) |
| goto bp_err; |
| } else { |
| start_blk = 0; |
| ASSERT(head_blk <= INT_MAX); |
| error = xlog_find_verify_log_record(log, start_blk, &head_blk, 0); |
| if (error < 0) |
| goto bp_err; |
| if (error == 1) { |
| /* We hit the beginning of the log during our search */ |
| start_blk = log_bbnum - (num_scan_bblks - head_blk); |
| new_blk = log_bbnum; |
| ASSERT(start_blk <= INT_MAX && |
| (xfs_daddr_t) log_bbnum-start_blk >= 0); |
| ASSERT(head_blk <= INT_MAX); |
| error = xlog_find_verify_log_record(log, start_blk, |
| &new_blk, (int)head_blk); |
| if (error == 1) |
| error = -EIO; |
| if (error) |
| goto bp_err; |
| if (new_blk != log_bbnum) |
| head_blk = new_blk; |
| } else if (error) |
| goto bp_err; |
| } |
| |
| xlog_put_bp(bp); |
| if (head_blk == log_bbnum) |
| *return_head_blk = 0; |
| else |
| *return_head_blk = head_blk; |
| /* |
| * When returning here, we have a good block number. Bad block |
| * means that during a previous crash, we didn't have a clean break |
| * from cycle number N to cycle number N-1. In this case, we need |
| * to find the first block with cycle number N-1. |
| */ |
| return 0; |
| |
| bp_err: |
| xlog_put_bp(bp); |
| |
| if (error) |
| xfs_warn(log->l_mp, "failed to find log head"); |
| return error; |
| } |
| |
| /* |
| * Seek backwards in the log for log record headers. |
| * |
| * Given a starting log block, walk backwards until we find the provided number |
| * of records or hit the provided tail block. The return value is the number of |
| * records encountered or a negative error code. The log block and buffer |
| * pointer of the last record seen are returned in rblk and rhead respectively. |
| */ |
| STATIC int |
| xlog_rseek_logrec_hdr( |
| struct xlog *log, |
| xfs_daddr_t head_blk, |
| xfs_daddr_t tail_blk, |
| int count, |
| struct xfs_buf *bp, |
| xfs_daddr_t *rblk, |
| struct xlog_rec_header **rhead, |
| bool *wrapped) |
| { |
| int i; |
| int error; |
| int found = 0; |
| char *offset = NULL; |
| xfs_daddr_t end_blk; |
| |
| *wrapped = false; |
| |
| /* |
| * Walk backwards from the head block until we hit the tail or the first |
| * block in the log. |
| */ |
| end_blk = head_blk > tail_blk ? tail_blk : 0; |
| for (i = (int) head_blk - 1; i >= end_blk; i--) { |
| error = xlog_bread(log, i, 1, bp, &offset); |
| if (error) |
| goto out_error; |
| |
| if (*(__be32 *) offset == cpu_to_be32(XLOG_HEADER_MAGIC_NUM)) { |
| *rblk = i; |
| *rhead = (struct xlog_rec_header *) offset; |
| if (++found == count) |
| break; |
| } |
| } |
| |
| /* |
| * If we haven't hit the tail block or the log record header count, |
| * start looking again from the end of the physical log. Note that |
| * callers can pass head == tail if the tail is not yet known. |
| */ |
| if (tail_blk >= head_blk && found != count) { |
| for (i = log->l_logBBsize - 1; i >= (int) tail_blk; i--) { |
| error = xlog_bread(log, i, 1, bp, &offset); |
| if (error) |
| goto out_error; |
| |
| if (*(__be32 *)offset == |
| cpu_to_be32(XLOG_HEADER_MAGIC_NUM)) { |
| *wrapped = true; |
| *rblk = i; |
| *rhead = (struct xlog_rec_header *) offset; |
| if (++found == count) |
| break; |
| } |
| } |
| } |
| |
| return found; |
| |
| out_error: |
| return error; |
| } |
| |
| /* |
| * Seek forward in the log for log record headers. |
| * |
| * Given head and tail blocks, walk forward from the tail block until we find |
| * the provided number of records or hit the head block. The return value is the |
| * number of records encountered or a negative error code. The log block and |
| * buffer pointer of the last record seen are returned in rblk and rhead |
| * respectively. |
| */ |
| STATIC int |
| xlog_seek_logrec_hdr( |
| struct xlog *log, |
| xfs_daddr_t head_blk, |
| xfs_daddr_t tail_blk, |
| int count, |
| struct xfs_buf *bp, |
| xfs_daddr_t *rblk, |
| struct xlog_rec_header **rhead, |
| bool *wrapped) |
| { |
| int i; |
| int error; |
| int found = 0; |
| char *offset = NULL; |
| xfs_daddr_t end_blk; |
| |
| *wrapped = false; |
| |
| /* |
| * Walk forward from the tail block until we hit the head or the last |
| * block in the log. |
| */ |
| end_blk = head_blk > tail_blk ? head_blk : log->l_logBBsize - 1; |
| for (i = (int) tail_blk; i <= end_blk; i++) { |
| error = xlog_bread(log, i, 1, bp, &offset); |
| if (error) |
| goto out_error; |
| |
| if (*(__be32 *) offset == cpu_to_be32(XLOG_HEADER_MAGIC_NUM)) { |
| *rblk = i; |
| *rhead = (struct xlog_rec_header *) offset; |
| if (++found == count) |
| break; |
| } |
| } |
| |
| /* |
| * If we haven't hit the head block or the log record header count, |
| * start looking again from the start of the physical log. |
| */ |
| if (tail_blk > head_blk && found != count) { |
| for (i = 0; i < (int) head_blk; i++) { |
| error = xlog_bread(log, i, 1, bp, &offset); |
| if (error) |
| goto out_error; |
| |
| if (*(__be32 *)offset == |
| cpu_to_be32(XLOG_HEADER_MAGIC_NUM)) { |
| *wrapped = true; |
| *rblk = i; |
| *rhead = (struct xlog_rec_header *) offset; |
| if (++found == count) |
| break; |
| } |
| } |
| } |
| |
| return found; |
| |
| out_error: |
| return error; |
| } |
| |
| /* |
| * Calculate distance from head to tail (i.e., unused space in the log). |
| */ |
| static inline int |
| xlog_tail_distance( |
| struct xlog *log, |
| xfs_daddr_t head_blk, |
| xfs_daddr_t tail_blk) |
| { |
| if (head_blk < tail_blk) |
| return tail_blk - head_blk; |
| |
| return tail_blk + (log->l_logBBsize - head_blk); |
| } |
| |
| /* |
| * Verify the log tail. This is particularly important when torn or incomplete |
| * writes have been detected near the front of the log and the head has been |
| * walked back accordingly. |
| * |
| * We also have to handle the case where the tail was pinned and the head |
| * blocked behind the tail right before a crash. If the tail had been pushed |
| * immediately prior to the crash and the subsequent checkpoint was only |
| * partially written, it's possible it overwrote the last referenced tail in the |
| * log with garbage. This is not a coherency problem because the tail must have |
| * been pushed before it can be overwritten, but appears as log corruption to |
| * recovery because we have no way to know the tail was updated if the |
| * subsequent checkpoint didn't write successfully. |
| * |
| * Therefore, CRC check the log from tail to head. If a failure occurs and the |
| * offending record is within max iclog bufs from the head, walk the tail |
| * forward and retry until a valid tail is found or corruption is detected out |
| * of the range of a possible overwrite. |
| */ |
| STATIC int |
| xlog_verify_tail( |
| struct xlog *log, |
| xfs_daddr_t head_blk, |
| xfs_daddr_t *tail_blk, |
| int hsize) |
| { |
| struct xlog_rec_header *thead; |
| struct xfs_buf *bp; |
| xfs_daddr_t first_bad; |
| int error = 0; |
| bool wrapped; |
| xfs_daddr_t tmp_tail; |
| xfs_daddr_t orig_tail = *tail_blk; |
| |
| bp = xlog_get_bp(log, 1); |
| if (!bp) |
| return -ENOMEM; |
| |
| /* |
| * Make sure the tail points to a record (returns positive count on |
| * success). |
| */ |
| error = xlog_seek_logrec_hdr(log, head_blk, *tail_blk, 1, bp, |
| &tmp_tail, &thead, &wrapped); |
| if (error < 0) |
| goto out; |
| if (*tail_blk != tmp_tail) |
| *tail_blk = tmp_tail; |
| |
| /* |
| * Run a CRC check from the tail to the head. We can't just check |
| * MAX_ICLOGS records past the tail because the tail may point to stale |
| * blocks cleared during the search for the head/tail. These blocks are |
| * overwritten with zero-length records and thus record count is not a |
| * reliable indicator of the iclog state before a crash. |
| */ |
| first_bad = 0; |
| error = xlog_do_recovery_pass(log, head_blk, *tail_blk, |
| XLOG_RECOVER_CRCPASS, &first_bad); |
| while ((error == -EFSBADCRC || error == -EFSCORRUPTED) && first_bad) { |
| int tail_distance; |
| |
| /* |
| * Is corruption within range of the head? If so, retry from |
| * the next record. Otherwise return an error. |
| */ |
| tail_distance = xlog_tail_distance(log, head_blk, first_bad); |
| if (tail_distance > BTOBB(XLOG_MAX_ICLOGS * hsize)) |
| break; |
| |
| /* skip to the next record; returns positive count on success */ |
| error = xlog_seek_logrec_hdr(log, head_blk, first_bad, 2, bp, |
| &tmp_tail, &thead, &wrapped); |
| if (error < 0) |
| goto out; |
| |
| *tail_blk = tmp_tail; |
| first_bad = 0; |
| error = xlog_do_recovery_pass(log, head_blk, *tail_blk, |
| XLOG_RECOVER_CRCPASS, &first_bad); |
| } |
| |
| if (!error && *tail_blk != orig_tail) |
| xfs_warn(log->l_mp, |
| "Tail block (0x%llx) overwrite detected. Updated to 0x%llx", |
| orig_tail, *tail_blk); |
| out: |
| xlog_put_bp(bp); |
| return error; |
| } |
| |
| /* |
| * Detect and trim torn writes from the head of the log. |
| * |
| * Storage without sector atomicity guarantees can result in torn writes in the |
| * log in the event of a crash. Our only means to detect this scenario is via |
| * CRC verification. While we can't always be certain that CRC verification |
| * failure is due to a torn write vs. an unrelated corruption, we do know that |
| * only a certain number (XLOG_MAX_ICLOGS) of log records can be written out at |
| * one time. Therefore, CRC verify up to XLOG_MAX_ICLOGS records at the head of |
| * the log and treat failures in this range as torn writes as a matter of |
| * policy. In the event of CRC failure, the head is walked back to the last good |
| * record in the log and the tail is updated from that record and verified. |
| */ |
| STATIC int |
| xlog_verify_head( |
| struct xlog *log, |
| xfs_daddr_t *head_blk, /* in/out: unverified head */ |
| xfs_daddr_t *tail_blk, /* out: tail block */ |
| struct xfs_buf *bp, |
| xfs_daddr_t *rhead_blk, /* start blk of last record */ |
| struct xlog_rec_header **rhead, /* ptr to last record */ |
| bool *wrapped) /* last rec. wraps phys. log */ |
| { |
| struct xlog_rec_header *tmp_rhead; |
| struct xfs_buf *tmp_bp; |
| xfs_daddr_t first_bad; |
| xfs_daddr_t tmp_rhead_blk; |
| int found; |
| int error; |
| bool tmp_wrapped; |
| |
| /* |
| * Check the head of the log for torn writes. Search backwards from the |
| * head until we hit the tail or the maximum number of log record I/Os |
| * that could have been in flight at one time. Use a temporary buffer so |
| * we don't trash the rhead/bp pointers from the caller. |
| */ |
| tmp_bp = xlog_get_bp(log, 1); |
| if (!tmp_bp) |
| return -ENOMEM; |
| error = xlog_rseek_logrec_hdr(log, *head_blk, *tail_blk, |
| XLOG_MAX_ICLOGS, tmp_bp, &tmp_rhead_blk, |
| &tmp_rhead, &tmp_wrapped); |
| xlog_put_bp(tmp_bp); |
| if (error < 0) |
| return error; |
| |
| /* |
| * Now run a CRC verification pass over the records starting at the |
| * block found above to the current head. If a CRC failure occurs, the |
| * log block of the first bad record is saved in first_bad. |
| */ |
| error = xlog_do_recovery_pass(log, *head_blk, tmp_rhead_blk, |
| XLOG_RECOVER_CRCPASS, &first_bad); |
| if ((error == -EFSBADCRC || error == -EFSCORRUPTED) && first_bad) { |
| /* |
| * We've hit a potential torn write. Reset the error and warn |
| * about it. |
| */ |
| error = 0; |
| xfs_warn(log->l_mp, |
| "Torn write (CRC failure) detected at log block 0x%llx. Truncating head block from 0x%llx.", |
| first_bad, *head_blk); |
| |
| /* |
| * Get the header block and buffer pointer for the last good |
| * record before the bad record. |
| * |
| * Note that xlog_find_tail() clears the blocks at the new head |
| * (i.e., the records with invalid CRC) if the cycle number |
| * matches the the current cycle. |
| */ |
| found = xlog_rseek_logrec_hdr(log, first_bad, *tail_blk, 1, bp, |
| rhead_blk, rhead, wrapped); |
| if (found < 0) |
| return found; |
| if (found == 0) /* XXX: right thing to do here? */ |
| return -EIO; |
| |
| /* |
| * Reset the head block to the starting block of the first bad |
| * log record and set the tail block based on the last good |
| * record. |
| * |
| * Bail out if the updated head/tail match as this indicates |
| * possible corruption outside of the acceptable |
| * (XLOG_MAX_ICLOGS) range. This is a job for xfs_repair... |
| */ |
| *head_blk = first_bad; |
| *tail_blk = BLOCK_LSN(be64_to_cpu((*rhead)->h_tail_lsn)); |
| if (*head_blk == *tail_blk) { |
| ASSERT(0); |
| return 0; |
| } |
| } |
| if (error) |
| return error; |
| |
| return xlog_verify_tail(log, *head_blk, tail_blk, |
| be32_to_cpu((*rhead)->h_size)); |
| } |
| |
| /* |
| * Check whether the head of the log points to an unmount record. In other |
| * words, determine whether the log is clean. If so, update the in-core state |
| * appropriately. |
| */ |
| static int |
| xlog_check_unmount_rec( |
| struct xlog *log, |
| xfs_daddr_t *head_blk, |
| xfs_daddr_t *tail_blk, |
| struct xlog_rec_header *rhead, |
| xfs_daddr_t rhead_blk, |
| struct xfs_buf *bp, |
| bool *clean) |
| { |
| struct xlog_op_header *op_head; |
| xfs_daddr_t umount_data_blk; |
| xfs_daddr_t after_umount_blk; |
| int hblks; |
| int error; |
| char *offset; |
| |
| *clean = false; |
| |
| /* |
| * Look for unmount record. If we find it, then we know there was a |
| * clean unmount. Since 'i' could be the last block in the physical |
| * log, we convert to a log block before comparing to the head_blk. |
| * |
| * Save the current tail lsn to use to pass to xlog_clear_stale_blocks() |
| * below. We won't want to clear the unmount record if there is one, so |
| * we pass the lsn of the unmount record rather than the block after it. |
| */ |
| if (xfs_sb_version_haslogv2(&log->l_mp->m_sb)) { |
| int h_size = be32_to_cpu(rhead->h_size); |
| int h_version = be32_to_cpu(rhead->h_version); |
| |
| if ((h_version & XLOG_VERSION_2) && |
| (h_size > XLOG_HEADER_CYCLE_SIZE)) { |
| hblks = h_size / XLOG_HEADER_CYCLE_SIZE; |
| if (h_size % XLOG_HEADER_CYCLE_SIZE) |
| hblks++; |
| } else { |
| hblks = 1; |
| } |
| } else { |
| hblks = 1; |
| } |
| after_umount_blk = rhead_blk + hblks + BTOBB(be32_to_cpu(rhead->h_len)); |
| after_umount_blk = do_mod(after_umount_blk, log->l_logBBsize); |
| if (*head_blk == after_umount_blk && |
| be32_to_cpu(rhead->h_num_logops) == 1) { |
| umount_data_blk = rhead_blk + hblks; |
| umount_data_blk = do_mod(umount_data_blk, log->l_logBBsize); |
| error = xlog_bread(log, umount_data_blk, 1, bp, &offset); |
| if (error) |
| return error; |
| |
| op_head = (struct xlog_op_header *)offset; |
| if (op_head->oh_flags & XLOG_UNMOUNT_TRANS) { |
| /* |
| * Set tail and last sync so that newly written log |
| * records will point recovery to after the current |
| * unmount record. |
| */ |
| xlog_assign_atomic_lsn(&log->l_tail_lsn, |
| log->l_curr_cycle, after_umount_blk); |
| xlog_assign_atomic_lsn(&log->l_last_sync_lsn, |
| log->l_curr_cycle, after_umount_blk); |
| *tail_blk = after_umount_blk; |
| |
| *clean = true; |
| } |
| } |
| |
| return 0; |
| } |
| |
| static void |
| xlog_set_state( |
| struct xlog *log, |
| xfs_daddr_t head_blk, |
| struct xlog_rec_header *rhead, |
| xfs_daddr_t rhead_blk, |
| bool bump_cycle) |
| { |
| /* |
| * Reset log values according to the state of the log when we |
| * crashed. In the case where head_blk == 0, we bump curr_cycle |
| * one because the next write starts a new cycle rather than |
| * continuing the cycle of the last good log record. At this |
| * point we have guaranteed that all partial log records have been |
| * accounted for. Therefore, we know that the last good log record |
| * written was complete and ended exactly on the end boundary |
| * of the physical log. |
| */ |
| log->l_prev_block = rhead_blk; |
| log->l_curr_block = (int)head_blk; |
| log->l_curr_cycle = be32_to_cpu(rhead->h_cycle); |
| if (bump_cycle) |
| log->l_curr_cycle++; |
| atomic64_set(&log->l_tail_lsn, be64_to_cpu(rhead->h_tail_lsn)); |
| atomic64_set(&log->l_last_sync_lsn, be64_to_cpu(rhead->h_lsn)); |
| xlog_assign_grant_head(&log->l_reserve_head.grant, log->l_curr_cycle, |
| BBTOB(log->l_curr_block)); |
| xlog_assign_grant_head(&log->l_write_head.grant, log->l_curr_cycle, |
| BBTOB(log->l_curr_block)); |
| } |
| |
| /* |
| * Find the sync block number or the tail of the log. |
| * |
| * This will be the block number of the last record to have its |
| * associated buffers synced to disk. Every log record header has |
| * a sync lsn embedded in it. LSNs hold block numbers, so it is easy |
| * to get a sync block number. The only concern is to figure out which |
| * log record header to believe. |
| * |
| * The following algorithm uses the log record header with the largest |
| * lsn. The entire log record does not need to be valid. We only care |
| * that the header is valid. |
| * |
| * We could speed up search by using current head_blk buffer, but it is not |
| * available. |
| */ |
| STATIC int |
| xlog_find_tail( |
| struct xlog *log, |
| xfs_daddr_t *head_blk, |
| xfs_daddr_t *tail_blk) |
| { |
| xlog_rec_header_t *rhead; |
| char *offset = NULL; |
| xfs_buf_t *bp; |
| int error; |
| xfs_daddr_t rhead_blk; |
| xfs_lsn_t tail_lsn; |
| bool wrapped = false; |
| bool clean = false; |
| |
| /* |
| * Find previous log record |
| */ |
| if ((error = xlog_find_head(log, head_blk))) |
| return error; |
| ASSERT(*head_blk < INT_MAX); |
| |
| bp = xlog_get_bp(log, 1); |
| if (!bp) |
| return -ENOMEM; |
| if (*head_blk == 0) { /* special case */ |
| error = xlog_bread(log, 0, 1, bp, &offset); |
| if (error) |
| goto done; |
| |
| if (xlog_get_cycle(offset) == 0) { |
| *tail_blk = 0; |
| /* leave all other log inited values alone */ |
| goto done; |
| } |
| } |
| |
| /* |
| * Search backwards through the log looking for the log record header |
| * block. This wraps all the way back around to the head so something is |
| * seriously wrong if we can't find it. |
| */ |
| error = xlog_rseek_logrec_hdr(log, *head_blk, *head_blk, 1, bp, |
| &rhead_blk, &rhead, &wrapped); |
| if (error < 0) |
| return error; |
| if (!error) { |
| xfs_warn(log->l_mp, "%s: couldn't find sync record", __func__); |
| return -EIO; |
| } |
| *tail_blk = BLOCK_LSN(be64_to_cpu(rhead->h_tail_lsn)); |
| |
| /* |
| * Set the log state based on the current head record. |
| */ |
| xlog_set_state(log, *head_blk, rhead, rhead_blk, wrapped); |
| tail_lsn = atomic64_read(&log->l_tail_lsn); |
| |
| /* |
| * Look for an unmount record at the head of the log. This sets the log |
| * state to determine whether recovery is necessary. |
| */ |
| error = xlog_check_unmount_rec(log, head_blk, tail_blk, rhead, |
| rhead_blk, bp, &clean); |
| if (error) |
| goto done; |
| |
| /* |
| * Verify the log head if the log is not clean (e.g., we have anything |
| * but an unmount record at the head). This uses CRC verification to |
| * detect and trim torn writes. If discovered, CRC failures are |
| * considered torn writes and the log head is trimmed accordingly. |
| * |
| * Note that we can only run CRC verification when the log is dirty |
| * because there's no guarantee that the log data behind an unmount |
| * record is compatible with the current architecture. |
| */ |
| if (!clean) { |
| xfs_daddr_t orig_head = *head_blk; |
| |
| error = xlog_verify_head(log, head_blk, tail_blk, bp, |
| &rhead_blk, &rhead, &wrapped); |
| if (error) |
| goto done; |
| |
| /* update in-core state again if the head changed */ |
| if (*head_blk != orig_head) { |
| xlog_set_state(log, *head_blk, rhead, rhead_blk, |
| wrapped); |
| tail_lsn = atomic64_read(&log->l_tail_lsn); |
| error = xlog_check_unmount_rec(log, head_blk, tail_blk, |
| rhead, rhead_blk, bp, |
| &clean); |
| if (error) |
| goto done; |
| } |
| } |
| |
| /* |
| * Note that the unmount was clean. If the unmount was not clean, we |
| * need to know this to rebuild the superblock counters from the perag |
| * headers if we have a filesystem using non-persistent counters. |
| */ |
| if (clean) |
| log->l_mp->m_flags |= XFS_MOUNT_WAS_CLEAN; |
| |
| /* |
| * Make sure that there are no blocks in front of the head |
| * with the same cycle number as the head. This can happen |
| * because we allow multiple outstanding log writes concurrently, |
| * and the later writes might make it out before earlier ones. |
| * |
| * We use the lsn from before modifying it so that we'll never |
| * overwrite the unmount record after a clean unmount. |
| * |
| * Do this only if we are going to recover the filesystem |
| * |
| * NOTE: This used to say "if (!readonly)" |
| * However on Linux, we can & do recover a read-only filesystem. |
| * We only skip recovery if NORECOVERY is specified on mount, |
| * in which case we would not be here. |
| * |
| * But... if the -device- itself is readonly, just skip this. |
| * We can't recover this device anyway, so it won't matter. |
| */ |
| if (!xfs_readonly_buftarg(log->l_mp->m_logdev_targp)) |
| error = xlog_clear_stale_blocks(log, tail_lsn); |
| |
| done: |
| xlog_put_bp(bp); |
| |
| if (error) |
| xfs_warn(log->l_mp, "failed to locate log tail"); |
| return error; |
| } |
| |
| /* |
| * Is the log zeroed at all? |
| * |
| * The last binary search should be changed to perform an X block read |
| * once X becomes small enough. You can then search linearly through |
| * the X blocks. This will cut down on the number of reads we need to do. |
| * |
| * If the log is partially zeroed, this routine will pass back the blkno |
| * of the first block with cycle number 0. It won't have a complete LR |
| * preceding it. |
| * |
| * Return: |
| * 0 => the log is completely written to |
| * 1 => use *blk_no as the first block of the log |
| * <0 => error has occurred |
| */ |
| STATIC int |
| xlog_find_zeroed( |
| struct xlog *log, |
| xfs_daddr_t *blk_no) |
| { |
| xfs_buf_t *bp; |
| char *offset; |
| uint first_cycle, last_cycle; |
| xfs_daddr_t new_blk, last_blk, start_blk; |
| xfs_daddr_t num_scan_bblks; |
| int error, log_bbnum = log->l_logBBsize; |
| |
| *blk_no = 0; |
| |
| /* check totally zeroed log */ |
| bp = xlog_get_bp(log, 1); |
| if (!bp) |
| return -ENOMEM; |
| error = xlog_bread(log, 0, 1, bp, &offset); |
| if (error) |
| goto bp_err; |
| |
| first_cycle = xlog_get_cycle(offset); |
| if (first_cycle == 0) { /* completely zeroed log */ |
| *blk_no = 0; |
| xlog_put_bp(bp); |
| return 1; |
| } |
| |
| /* check partially zeroed log */ |
| error = xlog_bread(log, log_bbnum-1, 1, bp, &offset); |
| if (error) |
| goto bp_err; |
| |
| last_cycle = xlog_get_cycle(offset); |
| if (last_cycle != 0) { /* log completely written to */ |
| xlog_put_bp(bp); |
| return 0; |
| } else if (first_cycle != 1) { |
| /* |
| * If the cycle of the last block is zero, the cycle of |
| * the first block must be 1. If it's not, maybe we're |
| * not looking at a log... Bail out. |
| */ |
| xfs_warn(log->l_mp, |
| "Log inconsistent or not a log (last==0, first!=1)"); |
| error = -EINVAL; |
| goto bp_err; |
| } |
| |
| /* we have a partially zeroed log */ |
| last_blk = log_bbnum-1; |
| if ((error = xlog_find_cycle_start(log, bp, 0, &last_blk, 0))) |
| goto bp_err; |
| |
| /* |
| * Validate the answer. Because there is no way to guarantee that |
| * the entire log is made up of log records which are the same size, |
| * we scan over the defined maximum blocks. At this point, the maximum |
| * is not chosen to mean anything special. XXXmiken |
| */ |
| num_scan_bblks = XLOG_TOTAL_REC_SHIFT(log); |
| ASSERT(num_scan_bblks <= INT_MAX); |
| |
| if (last_blk < num_scan_bblks) |
| num_scan_bblks = last_blk; |
| start_blk = last_blk - num_scan_bblks; |
| |
| /* |
| * We search for any instances of cycle number 0 that occur before |
| * our current estimate of the head. What we're trying to detect is |
| * 1 ... | 0 | 1 | 0... |
| * ^ binary search ends here |
| */ |
| if ((error = xlog_find_verify_cycle(log, start_blk, |
| (int)num_scan_bblks, 0, &new_blk))) |
| goto bp_err; |
| if (new_blk != -1) |
| last_blk = new_blk; |
| |
| /* |
| * Potentially backup over partial log record write. We don't need |
| * to search the end of the log because we know it is zero. |
| */ |
| error = xlog_find_verify_log_record(log, start_blk, &last_blk, 0); |
| if (error == 1) |
| error = -EIO; |
| if (error) |
| goto bp_err; |
| |
| *blk_no = last_blk; |
| bp_err: |
| xlog_put_bp(bp); |
| if (error) |
| return error; |
| return 1; |
| } |
| |
| /* |
| * These are simple subroutines used by xlog_clear_stale_blocks() below |
| * to initialize a buffer full of empty log record headers and write |
| * them into the log. |
| */ |
| STATIC void |
| xlog_add_record( |
| struct xlog *log, |
| char *buf, |
| int cycle, |
| int block, |
| int tail_cycle, |
| int tail_block) |
| { |
| xlog_rec_header_t *recp = (xlog_rec_header_t *)buf; |
| |
| memset(buf, 0, BBSIZE); |
| recp->h_magicno = cpu_to_be32(XLOG_HEADER_MAGIC_NUM); |
| recp->h_cycle = cpu_to_be32(cycle); |
| recp->h_version = cpu_to_be32( |
| xfs_sb_version_haslogv2(&log->l_mp->m_sb) ? 2 : 1); |
| recp->h_lsn = cpu_to_be64(xlog_assign_lsn(cycle, block)); |
| recp->h_tail_lsn = cpu_to_be64(xlog_assign_lsn(tail_cycle, tail_block)); |
| recp->h_fmt = cpu_to_be32(XLOG_FMT); |
| memcpy(&recp->h_fs_uuid, &log->l_mp->m_sb.sb_uuid, sizeof(uuid_t)); |
| } |
| |
| STATIC int |
| xlog_write_log_records( |
| struct xlog *log, |
| int cycle, |
| int start_block, |
| int blocks, |
| int tail_cycle, |
| int tail_block) |
| { |
| char *offset; |
| xfs_buf_t *bp; |
| int balign, ealign; |
| int sectbb = log->l_sectBBsize; |
| int end_block = start_block + blocks; |
| int bufblks; |
| int error = 0; |
| int i, j = 0; |
| |
| /* |
| * Greedily allocate a buffer big enough to handle the full |
| * range of basic blocks to be written. If that fails, try |
| * a smaller size. We need to be able to write at least a |
| * log sector, or we're out of luck. |
| */ |
| bufblks = 1 << ffs(blocks); |
| while (bufblks > log->l_logBBsize) |
| bufblks >>= 1; |
| while (!(bp = xlog_get_bp(log, bufblks))) { |
| bufblks >>= 1; |
| if (bufblks < sectbb) |
| return -ENOMEM; |
| } |
| |
| /* We may need to do a read at the start to fill in part of |
| * the buffer in the starting sector not covered by the first |
| * write below. |
| */ |
| balign = round_down(start_block, sectbb); |
| if (balign != start_block) { |
| error = xlog_bread_noalign(log, start_block, 1, bp); |
| if (error) |
| goto out_put_bp; |
| |
| j = start_block - balign; |
| } |
| |
| for (i = start_block; i < end_block; i += bufblks) { |
| int bcount, endcount; |
| |
| bcount = min(bufblks, end_block - start_block); |
| endcount = bcount - j; |
| |
| /* We may need to do a read at the end to fill in part of |
| * the buffer in the final sector not covered by the write. |
| * If this is the same sector as the above read, skip it. |
| */ |
| ealign = round_down(end_block, sectbb); |
| if (j == 0 && (start_block + endcount > ealign)) { |
| offset = bp->b_addr + BBTOB(ealign - start_block); |
| error = xlog_bread_offset(log, ealign, sectbb, |
| bp, offset); |
| if (error) |
| break; |
| |
| } |
| |
| offset = xlog_align(log, start_block, endcount, bp); |
| for (; j < endcount; j++) { |
| xlog_add_record(log, offset, cycle, i+j, |
| tail_cycle, tail_block); |
| offset += BBSIZE; |
| } |
| error = xlog_bwrite(log, start_block, endcount, bp); |
| if (error) |
| break; |
| start_block += endcount; |
| j = 0; |
| } |
| |
| out_put_bp: |
| xlog_put_bp(bp); |
| return error; |
| } |
| |
| /* |
| * This routine is called to blow away any incomplete log writes out |
| * in front of the log head. We do this so that we won't become confused |
| * if we come up, write only a little bit more, and then crash again. |
| * If we leave the partial log records out there, this situation could |
| * cause us to think those partial writes are valid blocks since they |
| * have the current cycle number. We get rid of them by overwriting them |
| * with empty log records with the old cycle number rather than the |
| * current one. |
| * |
| * The tail lsn is passed in rather than taken from |
| * the log so that we will not write over the unmount record after a |
| * clean unmount in a 512 block log. Doing so would leave the log without |
| * any valid log records in it until a new one was written. If we crashed |
| * during that time we would not be able to recover. |
| */ |
| STATIC int |
| xlog_clear_stale_blocks( |
| struct xlog *log, |
| xfs_lsn_t tail_lsn) |
| { |
| int tail_cycle, head_cycle; |
| int tail_block, head_block; |
| int tail_distance, max_distance; |
| int distance; |
| int error; |
| |
| tail_cycle = CYCLE_LSN(tail_lsn); |
| tail_block = BLOCK_LSN(tail_lsn); |
| head_cycle = log->l_curr_cycle; |
| head_block = log->l_curr_block; |
| |
| /* |
| * Figure out the distance between the new head of the log |
| * and the tail. We want to write over any blocks beyond the |
| * head that we may have written just before the crash, but |
| * we don't want to overwrite the tail of the log. |
| */ |
| if (head_cycle == tail_cycle) { |
| /* |
| * The tail is behind the head in the physical log, |
| * so the distance from the head to the tail is the |
| * distance from the head to the end of the log plus |
| * the distance from the beginning of the log to the |
| * tail. |
| */ |
| if (unlikely(head_block < tail_block || head_block >= log->l_logBBsize)) { |
| XFS_ERROR_REPORT("xlog_clear_stale_blocks(1)", |
| XFS_ERRLEVEL_LOW, log->l_mp); |
| return -EFSCORRUPTED; |
| } |
| tail_distance = tail_block + (log->l_logBBsize - head_block); |
| } else { |
| /* |
| * The head is behind the tail in the physical log, |
| * so the distance from the head to the tail is just |
| * the tail block minus the head block. |
| */ |
| if (unlikely(head_block >= tail_block || head_cycle != (tail_cycle + 1))){ |
| XFS_ERROR_REPORT("xlog_clear_stale_blocks(2)", |
| XFS_ERRLEVEL_LOW, log->l_mp); |
| return -EFSCORRUPTED; |
| } |
| tail_distance = tail_block - head_block; |
| } |
| |
| /* |
| * If the head is right up against the tail, we can't clear |
| * anything. |
| */ |
| if (tail_distance <= 0) { |
| ASSERT(tail_distance == 0); |
| return 0; |
| } |
| |
| max_distance = XLOG_TOTAL_REC_SHIFT(log); |
| /* |
| * Take the smaller of the maximum amount of outstanding I/O |
| * we could have and the distance to the tail to clear out. |
| * We take the smaller so that we don't overwrite the tail and |
| * we don't waste all day writing from the head to the tail |
| * for no reason. |
| */ |
| max_distance = MIN(max_distance, tail_distance); |
| |
| if ((head_block + max_distance) <= log->l_logBBsize) { |
| /* |
| * We can stomp all the blocks we need to without |
| * wrapping around the end of the log. Just do it |
| * in a single write. Use the cycle number of the |
| * current cycle minus one so that the log will look like: |
| * n ... | n - 1 ... |
| */ |
| error = xlog_write_log_records(log, (head_cycle - 1), |
| head_block, max_distance, tail_cycle, |
| tail_block); |
| if (error) |
| return error; |
| } else { |
| /* |
| * We need to wrap around the end of the physical log in |
| * order to clear all the blocks. Do it in two separate |
| * I/Os. The first write should be from the head to the |
| * end of the physical log, and it should use the current |
| * cycle number minus one just like above. |
| */ |
| distance = log->l_logBBsize - head_block; |
| error = xlog_write_log_records(log, (head_cycle - 1), |
| head_block, distance, tail_cycle, |
| tail_block); |
| |
| if (error) |
| return error; |
| |
| /* |
| * Now write the blocks at the start of the physical log. |
| * This writes the remainder of the blocks we want to clear. |
| * It uses the current cycle number since we're now on the |
| * same cycle as the head so that we get: |
| * n ... n ... | n - 1 ... |
| * ^^^^^ blocks we're writing |
| */ |
| distance = max_distance - (log->l_logBBsize - head_block); |
| error = xlog_write_log_records(log, head_cycle, 0, distance, |
| tail_cycle, tail_block); |
| if (error) |
| return error; |
| } |
| |
| return 0; |
| } |
| |
| /****************************************************************************** |
| * |
| * Log recover routines |
| * |
| ****************************************************************************** |
| */ |
| |
| /* |
| * Sort the log items in the transaction. |
| * |
| * The ordering constraints are defined by the inode allocation and unlink |
| * behaviour. The rules are: |
| * |
| * 1. Every item is only logged once in a given transaction. Hence it |
| * represents the last logged state of the item. Hence ordering is |
| * dependent on the order in which operations need to be performed so |
| * required initial conditions are always met. |
| * |
| * 2. Cancelled buffers are recorded in pass 1 in a separate table and |
| * there's nothing to replay from them so we can simply cull them |
| * from the transaction. However, we can't do that until after we've |
| * replayed all the other items because they may be dependent on the |
| * cancelled buffer and replaying the cancelled buffer can remove it |
| * form the cancelled buffer table. Hence they have tobe done last. |
| * |
| * 3. Inode allocation buffers must be replayed before inode items that |
| * read the buffer and replay changes into it. For filesystems using the |
| * ICREATE transactions, this means XFS_LI_ICREATE objects need to get |
| * treated the same as inode allocation buffers as they create and |
| * initialise the buffers directly. |
| * |
| * 4. Inode unlink buffers must be replayed after inode items are replayed. |
| * This ensures that inodes are completely flushed to the inode buffer |
| * in a "free" state before we remove the unlinked inode list pointer. |
| * |
| * Hence the ordering needs to be inode allocation buffers first, inode items |
| * second, inode unlink buffers third and cancelled buffers last. |
| * |
| * But there's a problem with that - we can't tell an inode allocation buffer |
| * apart from a regular buffer, so we can't separate them. We can, however, |
| * tell an inode unlink buffer from the others, and so we can separate them out |
| * from all the other buffers and move them to last. |
| * |
| * Hence, 4 lists, in order from head to tail: |
| * - buffer_list for all buffers except cancelled/inode unlink buffers |
| * - item_list for all non-buffer items |
| * - inode_buffer_list for inode unlink buffers |
| * - cancel_list for the cancelled buffers |
| * |
| * Note that we add objects to the tail of the lists so that first-to-last |
| * ordering is preserved within the lists. Adding objects to the head of the |
| * list means when we traverse from the head we walk them in last-to-first |
| * order. For cancelled buffers and inode unlink buffers this doesn't matter, |
| * but for all other items there may be specific ordering that we need to |
| * preserve. |
| */ |
| STATIC int |
| xlog_recover_reorder_trans( |
| struct xlog *log, |
| struct xlog_recover *trans, |
| int pass) |
| { |
| xlog_recover_item_t *item, *n; |
| int error = 0; |
| LIST_HEAD(sort_list); |
| LIST_HEAD(cancel_list); |
| LIST_HEAD(buffer_list); |
| LIST_HEAD(inode_buffer_list); |
| LIST_HEAD(inode_list); |
| |
| list_splice_init(&trans->r_itemq, &sort_list); |
| list_for_each_entry_safe(item, n, &sort_list, ri_list) { |
| xfs_buf_log_format_t *buf_f = item->ri_buf[0].i_addr; |
| |
| switch (ITEM_TYPE(item)) { |
| case XFS_LI_ICREATE: |
| list_move_tail(&item->ri_list, &buffer_list); |
| break; |
| case XFS_LI_BUF: |
| if (buf_f->blf_flags & XFS_BLF_CANCEL) { |
| trace_xfs_log_recover_item_reorder_head(log, |
| trans, item, pass); |
| list_move(&item->ri_list, &cancel_list); |
| break; |
| } |
| if (buf_f->blf_flags & XFS_BLF_INODE_BUF) { |
| list_move(&item->ri_list, &inode_buffer_list); |
| break; |
| } |
| list_move_tail(&item->ri_list, &buffer_list); |
| break; |
| case XFS_LI_INODE: |
| case XFS_LI_DQUOT: |
| case XFS_LI_QUOTAOFF: |
| case XFS_LI_EFD: |
| case XFS_LI_EFI: |
| case XFS_LI_RUI: |
| case XFS_LI_RUD: |
| case XFS_LI_CUI: |
| case XFS_LI_CUD: |
| case XFS_LI_BUI: |
| case XFS_LI_BUD: |
| trace_xfs_log_recover_item_reorder_tail(log, |
| trans, item, pass); |
| list_move_tail(&item->ri_list, &inode_list); |
| break; |
| default: |
| xfs_warn(log->l_mp, |
| "%s: unrecognized type of log operation", |
| __func__); |
| ASSERT(0); |
| /* |
| * return the remaining items back to the transaction |
| * item list so they can be freed in caller. |
| */ |
| if (!list_empty(&sort_list)) |
| list_splice_init(&sort_list, &trans->r_itemq); |
| error = -EIO; |
| goto out; |
| } |
| } |
| out: |
| ASSERT(list_empty(&sort_list)); |
| if (!list_empty(&buffer_list)) |
| list_splice(&buffer_list, &trans->r_itemq); |
| if (!list_empty(&inode_list)) |
| list_splice_tail(&inode_list, &trans->r_itemq); |
| if (!list_empty(&inode_buffer_list)) |
| list_splice_tail(&inode_buffer_list, &trans->r_itemq); |
| if (!list_empty(&cancel_list)) |
| list_splice_tail(&cancel_list, &trans->r_itemq); |
| return error; |
| } |
| |
| /* |
| * Build up the table of buf cancel records so that we don't replay |
| * cancelled data in the second pass. For buffer records that are |
| * not cancel records, there is nothing to do here so we just return. |
| * |
| * If we get a cancel record which is already in the table, this indicates |
| * that the buffer was cancelled multiple times. In order to ensure |
| * that during pass 2 we keep the record in the table until we reach its |
| * last occurrence in the log, we keep a reference count in the cancel |
| * record in the table to tell us how many times we expect to see this |
| * record during the second pass. |
| */ |
| STATIC int |
| xlog_recover_buffer_pass1( |
| struct xlog *log, |
| struct xlog_recover_item *item) |
| { |
| xfs_buf_log_format_t *buf_f = item->ri_buf[0].i_addr; |
| struct list_head *bucket; |
| struct xfs_buf_cancel *bcp; |
| |
| /* |
| * If this isn't a cancel buffer item, then just return. |
| */ |
| if (!(buf_f->blf_flags & XFS_BLF_CANCEL)) { |
| trace_xfs_log_recover_buf_not_cancel(log, buf_f); |
| return 0; |
| } |
| |
| /* |
| * Insert an xfs_buf_cancel record into the hash table of them. |
| * If there is already an identical record, bump its reference count. |
| */ |
| bucket = XLOG_BUF_CANCEL_BUCKET(log, buf_f->blf_blkno); |
| list_for_each_entry(bcp, bucket, bc_list) { |
| if (bcp->bc_blkno == buf_f->blf_blkno && |
| bcp->bc_len == buf_f->blf_len) { |
| bcp->bc_refcount++; |
| trace_xfs_log_recover_buf_cancel_ref_inc(log, buf_f); |
| return 0; |
| } |
| } |
| |
| bcp = kmem_alloc(sizeof(struct xfs_buf_cancel), KM_SLEEP); |
| bcp->bc_blkno = buf_f->blf_blkno; |
| bcp->bc_len = buf_f->blf_len; |
| bcp->bc_refcount = 1; |
| list_add_tail(&bcp->bc_list, bucket); |
| |
| trace_xfs_log_recover_buf_cancel_add(log, buf_f); |
| return 0; |
| } |
| |
| /* |
| * Check to see whether the buffer being recovered has a corresponding |
| * entry in the buffer cancel record table. If it is, return the cancel |
| * buffer structure to the caller. |
| */ |
| STATIC struct xfs_buf_cancel * |
| xlog_peek_buffer_cancelled( |
| struct xlog *log, |
| xfs_daddr_t blkno, |
| uint len, |
| unsigned short flags) |
| { |
| struct list_head *bucket; |
| struct xfs_buf_cancel *bcp; |
| |
| if (!log->l_buf_cancel_table) { |
| /* empty table means no cancelled buffers in the log */ |
| ASSERT(!(flags & XFS_BLF_CANCEL)); |
| return NULL; |
| } |
| |
| bucket = XLOG_BUF_CANCEL_BUCKET(log, blkno); |
| list_for_each_entry(bcp, bucket, bc_list) { |
| if (bcp->bc_blkno == blkno && bcp->bc_len == len) |
| return bcp; |
| } |
| |
| /* |
| * We didn't find a corresponding entry in the table, so return 0 so |
| * that the buffer is NOT cancelled. |
| */ |
| ASSERT(!(flags & XFS_BLF_CANCEL)); |
| return NULL; |
| } |
| |
| /* |
| * If the buffer is being cancelled then return 1 so that it will be cancelled, |
| * otherwise return 0. If the buffer is actually a buffer cancel item |
| * (XFS_BLF_CANCEL is set), then decrement the refcount on the entry in the |
| * table and remove it from the table if this is the last reference. |
| * |
| * We remove the cancel record from the table when we encounter its last |
| * occurrence in the log so that if the same buffer is re-used again after its |
| * last cancellation we actually replay the changes made at that point. |
| */ |
| STATIC int |
| xlog_check_buffer_cancelled( |
| struct xlog *log, |
| xfs_daddr_t blkno, |
| uint len, |
| unsigned short flags) |
| { |
| struct xfs_buf_cancel *bcp; |
| |
| bcp = xlog_peek_buffer_cancelled(log, blkno, len, flags); |
| if (!bcp) |
| return 0; |
| |
| /* |
| * We've go a match, so return 1 so that the recovery of this buffer |
| * is cancelled. If this buffer is actually a buffer cancel log |
| * item, then decrement the refcount on the one in the table and |
| * remove it if this is the last reference. |
| */ |
| if (flags & XFS_BLF_CANCEL) { |
| if (--bcp->bc_refcount == 0) { |
| list_del(&bcp->bc_list); |
| kmem_free(bcp); |
| } |
| } |
| return 1; |
| } |
| |
| /* |
| * Perform recovery for a buffer full of inodes. In these buffers, the only |
| * data which should be recovered is that which corresponds to the |
| * di_next_unlinked pointers in the on disk inode structures. The rest of the |
| * data for the inodes is always logged through the inodes themselves rather |
| * than the inode buffer and is recovered in xlog_recover_inode_pass2(). |
| * |
| * The only time when buffers full of inodes are fully recovered is when the |
| * buffer is full of newly allocated inodes. In this case the buffer will |
| * not be marked as an inode buffer and so will be sent to |
| * xlog_recover_do_reg_buffer() below during recovery. |
| */ |
| STATIC int |
| xlog_recover_do_inode_buffer( |
| struct xfs_mount *mp, |
| xlog_recover_item_t *item, |
| struct xfs_buf *bp, |
| xfs_buf_log_format_t *buf_f) |
| { |
| int i; |
| int item_index = 0; |
| int bit = 0; |
| int nbits = 0; |
| int reg_buf_offset = 0; |
| int reg_buf_bytes = 0; |
| int next_unlinked_offset; |
| int inodes_per_buf; |
| xfs_agino_t *logged_nextp; |
| xfs_agino_t *buffer_nextp; |
| |
| trace_xfs_log_recover_buf_inode_buf(mp->m_log, buf_f); |
| |
| /* |
| * Post recovery validation only works properly on CRC enabled |
| * filesystems. |
| */ |
| if (xfs_sb_version_hascrc(&mp->m_sb)) |
| bp->b_ops = &xfs_inode_buf_ops; |
| |
| inodes_per_buf = BBTOB(bp->b_io_length) >> mp->m_sb.sb_inodelog; |
| for (i = 0; i < inodes_per_buf; i++) { |
| next_unlinked_offset = (i * mp->m_sb.sb_inodesize) + |
| offsetof(xfs_dinode_t, di_next_unlinked); |
| |
| while (next_unlinked_offset >= |
| (reg_buf_offset + reg_buf_bytes)) { |
| /* |
| * The next di_next_unlinked field is beyond |
| * the current logged region. Find the next |
| * logged region that contains or is beyond |
| * the current di_next_unlinked field. |
| */ |
| bit += nbits; |
| bit = xfs_next_bit(buf_f->blf_data_map, |
| buf_f->blf_map_size, bit); |
| |
| /* |
| * If there are no more logged regions in the |
| * buffer, then we're done. |
| */ |
| if (bit == -1) |
| return 0; |
| |
| nbits = xfs_contig_bits(buf_f->blf_data_map, |
| buf_f->blf_map_size, bit); |
| ASSERT(nbits > 0); |
| reg_buf_offset = bit << XFS_BLF_SHIFT; |
| reg_buf_bytes = nbits << XFS_BLF_SHIFT; |
| item_index++; |
| } |
| |
| /* |
| * If the current logged region starts after the current |
| * di_next_unlinked field, then move on to the next |
| * di_next_unlinked field. |
| */ |
| if (next_unlinked_offset < reg_buf_offset) |
| continue; |
| |
| ASSERT(item->ri_buf[item_index].i_addr != NULL); |
| ASSERT((item->ri_buf[item_index].i_len % XFS_BLF_CHUNK) == 0); |
| ASSERT((reg_buf_offset + reg_buf_bytes) <= |
| BBTOB(bp->b_io_length)); |
| |
| /* |
| * The current logged region contains a copy of the |
| * current di_next_unlinked field. Extract its value |
| * and copy it to the buffer copy. |
| */ |
| logged_nextp = item->ri_buf[item_index].i_addr + |
| next_unlinked_offset - reg_buf_offset; |
| if (unlikely(*logged_nextp == 0)) { |
| xfs_alert(mp, |
| "Bad inode buffer log record (ptr = 0x%p, bp = 0x%p). " |
| "Trying to replay bad (0) inode di_next_unlinked field.", |
| item, bp); |
| XFS_ERROR_REPORT("xlog_recover_do_inode_buf", |
| XFS_ERRLEVEL_LOW, mp); |
| return -EFSCORRUPTED; |
| } |
| |
| buffer_nextp = xfs_buf_offset(bp, next_unlinked_offset); |
| *buffer_nextp = *logged_nextp; |
| |
| /* |
| * If necessary, recalculate the CRC in the on-disk inode. We |
| * have to leave the inode in a consistent state for whoever |
| * reads it next.... |
| */ |
| xfs_dinode_calc_crc(mp, |
| xfs_buf_offset(bp, i * mp->m_sb.sb_inodesize)); |
| |
| } |
| |
| return 0; |
| } |
| |
| /* |
| * V5 filesystems know the age of the buffer on disk being recovered. We can |
| * have newer objects on disk than we are replaying, and so for these cases we |
| * don't want to replay the current change as that will make the buffer contents |
| * temporarily invalid on disk. |
| * |
| * The magic number might not match the buffer type we are going to recover |
| * (e.g. reallocated blocks), so we ignore the xfs_buf_log_format flags. Hence |
| * extract the LSN of the existing object in the buffer based on it's current |
| * magic number. If we don't recognise the magic number in the buffer, then |
| * return a LSN of -1 so that the caller knows it was an unrecognised block and |
| * so can recover the buffer. |
| * |
| * Note: we cannot rely solely on magic number matches to determine that the |
| * buffer has a valid LSN - we also need to verify that it belongs to this |
| * filesystem, so we need to extract the object's LSN and compare it to that |
| * which we read from the superblock. If the UUIDs don't match, then we've got a |
| * stale metadata block from an old filesystem instance that we need to recover |
| * over the top of. |
| */ |
| static xfs_lsn_t |
| xlog_recover_get_buf_lsn( |
| struct xfs_mount *mp, |
| struct xfs_buf *bp) |
| { |
| uint32_t magic32; |
| uint16_t magic16; |
| uint16_t magicda; |
| void *blk = bp->b_addr; |
| uuid_t *uuid; |
| xfs_lsn_t lsn = -1; |
| |
| /* v4 filesystems always recover immediately */ |
| if (!xfs_sb_version_hascrc(&mp->m_sb)) |
| goto recover_immediately; |
| |
| magic32 = be32_to_cpu(*(__be32 *)blk); |
| switch (magic32) { |
| case XFS_ABTB_CRC_MAGIC: |
| case XFS_ABTC_CRC_MAGIC: |
| case XFS_ABTB_MAGIC: |
| case XFS_ABTC_MAGIC: |
| case XFS_RMAP_CRC_MAGIC: |
| case XFS_REFC_CRC_MAGIC: |
| case XFS_IBT_CRC_MAGIC: |
| case XFS_IBT_MAGIC: { |
| struct xfs_btree_block *btb = blk; |
| |
| lsn = be64_to_cpu(btb->bb_u.s.bb_lsn); |
| uuid = &btb->bb_u.s.bb_uuid; |
| break; |
| } |
| case XFS_BMAP_CRC_MAGIC: |
| case XFS_BMAP_MAGIC: { |
| struct xfs_btree_block *btb = blk; |
| |
| lsn = be64_to_cpu(btb->bb_u.l.bb_lsn); |
| uuid = &btb->bb_u.l.bb_uuid; |
| break; |
| } |
| case XFS_AGF_MAGIC: |
| lsn = be64_to_cpu(((struct xfs_agf *)blk)->agf_lsn); |
| uuid = &((struct xfs_agf *)blk)->agf_uuid; |
| break; |
| case XFS_AGFL_MAGIC: |
| lsn = be64_to_cpu(((struct xfs_agfl *)blk)->agfl_lsn); |
| uuid = &((struct xfs_agfl *)blk)->agfl_uuid; |
| break; |
| case XFS_AGI_MAGIC: |
| lsn = be64_to_cpu(((struct xfs_agi *)blk)->agi_lsn); |
| uuid = &((struct xfs_agi *)blk)->agi_uuid; |
| break; |
| case XFS_SYMLINK_MAGIC: |
| lsn = be64_to_cpu(((struct xfs_dsymlink_hdr *)blk)->sl_lsn); |
| uuid = &((struct xfs_dsymlink_hdr *)blk)->sl_uuid; |
| break; |
| case XFS_DIR3_BLOCK_MAGIC: |
| case XFS_DIR3_DATA_MAGIC: |
| case XFS_DIR3_FREE_MAGIC: |
| lsn = be64_to_cpu(((struct xfs_dir3_blk_hdr *)blk)->lsn); |
| uuid = &((struct xfs_dir3_blk_hdr *)blk)->uuid; |
| break; |
| case XFS_ATTR3_RMT_MAGIC: |
| /* |
| * Remote attr blocks are written synchronously, rather than |
| * being logged. That means they do not contain a valid LSN |
| * (i.e. transactionally ordered) in them, and hence any time we |
| * see a buffer to replay over the top of a remote attribute |
| * block we should simply do so. |
| */ |
| goto recover_immediately; |
| case XFS_SB_MAGIC: |
| /* |
| * superblock uuids are magic. We may or may not have a |
| * sb_meta_uuid on disk, but it will be set in the in-core |
| * superblock. We set the uuid pointer for verification |
| * according to the superblock feature mask to ensure we check |
| * the relevant UUID in the superblock. |
| */ |
| lsn = be64_to_cpu(((struct xfs_dsb *)blk)->sb_lsn); |
| if (xfs_sb_version_hasmetauuid(&mp->m_sb)) |
| uuid = &((struct xfs_dsb *)blk)->sb_meta_uuid; |
| else |
| uuid = &((struct xfs_dsb *)blk)->sb_uuid; |
| break; |
| default: |
| break; |
| } |
| |
| if (lsn != (xfs_lsn_t)-1) { |
| if (!uuid_equal(&mp->m_sb.sb_meta_uuid, uuid)) |
| goto recover_immediately; |
| return lsn; |
| } |
| |
| magicda = be16_to_cpu(((struct xfs_da_blkinfo *)blk)->magic); |
| switch (magicda) { |
| case XFS_DIR3_LEAF1_MAGIC: |
| case XFS_DIR3_LEAFN_MAGIC: |
| case XFS_DA3_NODE_MAGIC: |
| lsn = be64_to_cpu(((struct xfs_da3_blkinfo *)blk)->lsn); |
| uuid = &((struct xfs_da3_blkinfo *)blk)->uuid; |
| break; |
| default: |
| break; |
| } |
| |
| if (lsn != (xfs_lsn_t)-1) { |
| if (!uuid_equal(&mp->m_sb.sb_uuid, uuid)) |
| goto recover_immediately; |
| return lsn; |
| } |
| |
| /* |
| * We do individual object checks on dquot and inode buffers as they |
| * have their own individual LSN records. Also, we could have a stale |
| * buffer here, so we have to at least recognise these buffer types. |
| * |
| * A notd complexity here is inode unlinked list processing - it logs |
| * the inode directly in the buffer, but we don't know which inodes have |
| * been modified, and there is no global buffer LSN. Hence we need to |
| * recover all inode buffer types immediately. This problem will be |
| * fixed by logical logging of the unlinked list modifications. |
| */ |
| magic16 = be16_to_cpu(*(__be16 *)blk); |
| switch (magic16) { |
| case XFS_DQUOT_MAGIC: |
| case XFS_DINODE_MAGIC: |
| goto recover_immediately; |
| default: |
| break; |
| } |
| |
| /* unknown buffer contents, recover immediately */ |
| |
| recover_immediately: |
| return (xfs_lsn_t)-1; |
| |
| } |
| |
| /* |
| * Validate the recovered buffer is of the correct type and attach the |
| * appropriate buffer operations to them for writeback. Magic numbers are in a |
| * few places: |
| * the first 16 bits of the buffer (inode buffer, dquot buffer), |
| * the first 32 bits of the buffer (most blocks), |
| * inside a struct xfs_da_blkinfo at the start of the buffer. |
| */ |
| static void |
| xlog_recover_validate_buf_type( |
| struct xfs_mount *mp, |
| struct xfs_buf *bp, |
| xfs_buf_log_format_t *buf_f, |
| xfs_lsn_t current_lsn) |
| { |
| struct xfs_da_blkinfo *info = bp->b_addr; |
| uint32_t magic32; |
| uint16_t magic16; |
| uint16_t magicda; |
| char *warnmsg = NULL; |
| |
| /* |
| * We can only do post recovery validation on items on CRC enabled |
| * fielsystems as we need to know when the buffer was written to be able |
| * to determine if we should have replayed the item. If we replay old |
| * metadata over a newer buffer, then it will enter a temporarily |
| * inconsistent state resulting in verification failures. Hence for now |
| * just avoid the verification stage for non-crc filesystems |
| */ |
| if (!xfs_sb_version_hascrc(&mp->m_sb)) |
| return; |
| |
| magic32 = be32_to_cpu(*(__be32 *)bp->b_addr); |
| magic16 = be16_to_cpu(*(__be16*)bp->b_addr); |
| magicda = be16_to_cpu(info->magic); |
| switch (xfs_blft_from_flags(buf_f)) { |
| case XFS_BLFT_BTREE_BUF: |
| switch (magic32) { |
| case XFS_ABTB_CRC_MAGIC: |
| case XFS_ABTC_CRC_MAGIC: |
| case XFS_ABTB_MAGIC: |
| case XFS_ABTC_MAGIC: |
| bp->b_ops = &xfs_allocbt_buf_ops; |
| break; |
| case XFS_IBT_CRC_MAGIC: |
| case XFS_FIBT_CRC_MAGIC: |
| case XFS_IBT_MAGIC: |
| case XFS_FIBT_MAGIC: |
| bp->b_ops = &xfs_inobt_buf_ops; |
| break; |
| case XFS_BMAP_CRC_MAGIC: |
| case XFS_BMAP_MAGIC: |
| bp->b_ops = &xfs_bmbt_buf_ops; |
| break; |
| case XFS_RMAP_CRC_MAGIC: |
| bp->b_ops = &xfs_rmapbt_buf_ops; |
| break; |
| case XFS_REFC_CRC_MAGIC: |
| bp->b_ops = &xfs_refcountbt_buf_ops; |
| break; |
| default: |
| warnmsg = "Bad btree block magic!"; |
| break; |
| } |
| break; |
| case XFS_BLFT_AGF_BUF: |
| if (magic32 != XFS_AGF_MAGIC) { |
| warnmsg = "Bad AGF block magic!"; |
| break; |
| } |
| bp->b_ops = &xfs_agf_buf_ops; |
| break; |
| case XFS_BLFT_AGFL_BUF: |
| if (magic32 != XFS_AGFL_MAGIC) { |
| warnmsg = "Bad AGFL block magic!"; |
| break; |
| } |
| bp->b_ops = &xfs_agfl_buf_ops; |
| break; |
| case XFS_BLFT_AGI_BUF: |
| if (magic32 != XFS_AGI_MAGIC) { |
| warnmsg = "Bad AGI block magic!"; |
| break; |
| } |
| bp->b_ops = &xfs_agi_buf_ops; |
| break; |
| case XFS_BLFT_UDQUOT_BUF: |
| case XFS_BLFT_PDQUOT_BUF: |
| case XFS_BLFT_GDQUOT_BUF: |
| #ifdef CONFIG_XFS_QUOTA |
| if (magic16 != XFS_DQUOT_MAGIC) { |
| warnmsg = "Bad DQUOT block magic!"; |
| break; |
| } |
| bp->b_ops = &xfs_dquot_buf_ops; |
| #else |
| xfs_alert(mp, |
| "Trying to recover dquots without QUOTA support built in!"); |
| ASSERT(0); |
| #endif |
| break; |
| case XFS_BLFT_DINO_BUF: |
| if (magic16 != XFS_DINODE_MAGIC) { |
| warnmsg = "Bad INODE block magic!"; |
| break; |
| } |
| bp->b_ops = &xfs_inode_buf_ops; |
| break; |
| case XFS_BLFT_SYMLINK_BUF: |
| if (magic32 != XFS_SYMLINK_MAGIC) { |
| warnmsg = "Bad symlink block magic!"; |
| break; |
| } |
| bp->b_ops = &xfs_symlink_buf_ops; |
| break; |
| case XFS_BLFT_DIR_BLOCK_BUF: |
| if (magic32 != XFS_DIR2_BLOCK_MAGIC && |
| magic32 != XFS_DIR3_BLOCK_MAGIC) { |
| warnmsg = "Bad dir block magic!"; |
| break; |
| } |
| bp->b_ops = &xfs_dir3_block_buf_ops; |
| break; |
| case XFS_BLFT_DIR_DATA_BUF: |
| if (magic32 != XFS_DIR2_DATA_MAGIC && |
| magic32 != XFS_DIR3_DATA_MAGIC) { |
| warnmsg = "Bad dir data magic!"; |
| break; |
| } |
| bp->b_ops = &xfs_dir3_data_buf_ops; |
| break; |
| case XFS_BLFT_DIR_FREE_BUF: |
| if (magic32 != XFS_DIR2_FREE_MAGIC && |
| magic32 != XFS_DIR3_FREE_MAGIC) { |
| warnmsg = "Bad dir3 free magic!"; |
| break; |
| } |
| bp->b_ops = &xfs_dir3_free_buf_ops; |
| break; |
| case XFS_BLFT_DIR_LEAF1_BUF: |
| if (magicda != XFS_DIR2_LEAF1_MAGIC && |
| magicda != XFS_DIR3_LEAF1_MAGIC) { |
| warnmsg = "Bad dir leaf1 magic!"; |
| break; |
| } |
| bp->b_ops = &xfs_dir3_leaf1_buf_ops; |
| break; |
| case XFS_BLFT_DIR_LEAFN_BUF: |
| if (magicda != XFS_DIR2_LEAFN_MAGIC && |
| magicda != XFS_DIR3_LEAFN_MAGIC) { |
| warnmsg = "Bad dir leafn magic!"; |
| break; |
| } |
| bp->b_ops = &xfs_dir3_leafn_buf_ops; |
| break; |
| case XFS_BLFT_DA_NODE_BUF: |
| if (magicda != XFS_DA_NODE_MAGIC && |
| magicda != XFS_DA3_NODE_MAGIC) { |
| warnmsg = "Bad da node magic!"; |
| break; |
| } |
| bp->b_ops = &xfs_da3_node_buf_ops; |
| break; |
| case XFS_BLFT_ATTR_LEAF_BUF: |
| if (magicda != XFS_ATTR_LEAF_MAGIC && |
| magicda != XFS_ATTR3_LEAF_MAGIC) { |
| warnmsg = "Bad attr leaf magic!"; |
| break; |
| } |
| bp->b_ops = &xfs_attr3_leaf_buf_ops; |
| break; |
| case XFS_BLFT_ATTR_RMT_BUF: |
| if (magic32 != XFS_ATTR3_RMT_MAGIC) { |
| warnmsg = "Bad attr remote magic!"; |
| break; |
| } |
| bp->b_ops = &xfs_attr3_rmt_buf_ops; |
| break; |
| case XFS_BLFT_SB_BUF: |
| if (magic32 != XFS_SB_MAGIC) { |
| warnmsg = "Bad SB block magic!"; |
| break; |
| } |
| bp->b_ops = &xfs_sb_buf_ops; |
| break; |
| #ifdef CONFIG_XFS_RT |
| case XFS_BLFT_RTBITMAP_BUF: |
| case XFS_BLFT_RTSUMMARY_BUF: |
| /* no magic numbers for verification of RT buffers */ |
| bp->b_ops = &xfs_rtbuf_ops; |
| break; |
| #endif /* CONFIG_XFS_RT */ |
| default: |
| xfs_warn(mp, "Unknown buffer type %d!", |
| xfs_blft_from_flags(buf_f)); |
| break; |
| } |
| |
| /* |
| * Nothing else to do in the case of a NULL current LSN as this means |
| * the buffer is more recent than the change in the log and will be |
| * skipped. |
| */ |
| if (current_lsn == NULLCOMMITLSN) |
| return; |
| |
| if (warnmsg) { |
| xfs_warn(mp, warnmsg); |
| ASSERT(0); |
| } |
| |
| /* |
| * We must update the metadata LSN of the buffer as it is written out to |
| * ensure that older transactions never replay over this one and corrupt |
| * the buffer. This can occur if log recovery is interrupted at some |
| * point after the current transaction completes, at which point a |
| * subsequent mount starts recovery from the beginning. |
| * |
| * Write verifiers update the metadata LSN from log items attached to |
| * the buffer. Therefore, initialize a bli purely to carry the LSN to |
| * the verifier. We'll clean it up in our ->iodone() callback. |
| */ |
| if (bp->b_ops) { |
| struct xfs_buf_log_item *bip; |
| |
| ASSERT(!bp->b_iodone || bp->b_iodone == xlog_recover_iodone); |
| bp->b_iodone = xlog_recover_iodone; |
| xfs_buf_item_init(bp, mp); |
| bip = bp->b_fspriv; |
| bip->bli_item.li_lsn = current_lsn; |
| } |
| } |
| |
| /* |
| * Perform a 'normal' buffer recovery. Each logged region of the |
| * buffer should be copied over the corresponding region in the |
| * given buffer. The bitmap in the buf log format structure indicates |
| * where to place the logged data. |
| */ |
| STATIC void |
| xlog_recover_do_reg_buffer( |
| struct xfs_mount *mp, |
| xlog_recover_item_t *item, |
| struct xfs_buf *bp, |
| xfs_buf_log_format_t *buf_f, |
| xfs_lsn_t current_lsn) |
| { |
| int i; |
| int bit; |
| int nbits; |
| int error; |
| |
| trace_xfs_log_recover_buf_reg_buf(mp->m_log, buf_f); |
| |
| bit = 0; |
| i = 1; /* 0 is the buf format structure */ |
| while (1) { |
| bit = xfs_next_bit(buf_f->blf_data_map, |
| buf_f->blf_map_size, bit); |
| if (bit == -1) |
| break; |
| nbits = xfs_contig_bits(buf_f->blf_data_map, |
| buf_f->blf_map_size, bit); |
| ASSERT(nbits > 0); |
| ASSERT(item->ri_buf[i].i_addr != NULL); |
| ASSERT(item->ri_buf[i].i_len % XFS_BLF_CHUNK == 0); |
| ASSERT(BBTOB(bp->b_io_length) >= |
| ((uint)bit << XFS_BLF_SHIFT) + (nbits << XFS_BLF_SHIFT)); |
| |
| /* |
| * The dirty regions logged in the buffer, even though |
| * contiguous, may span multiple chunks. This is because the |
| * dirty region may span a physical page boundary in a buffer |
| * and hence be split into two separate vectors for writing into |
| * the log. Hence we need to trim nbits back to the length of |
| * the current region being copied out of the log. |
| */ |
| if (item->ri_buf[i].i_len < (nbits << XFS_BLF_SHIFT)) |
| nbits = item->ri_buf[i].i_len >> XFS_BLF_SHIFT; |
| |
| /* |
| * Do a sanity check if this is a dquot buffer. Just checking |
| * the first dquot in the buffer should do. XXXThis is |
| * probably a good thing to do for other buf types also. |
| */ |
| error = 0; |
| if (buf_f->blf_flags & |
| (XFS_BLF_UDQUOT_BUF|XFS_BLF_PDQUOT_BUF|XFS_BLF_GDQUOT_BUF)) { |
| if (item->ri_buf[i].i_addr == NULL) { |
| xfs_alert(mp, |
| "XFS: NULL dquot in %s.", __func__); |
| goto next; |
| } |
| if (item->ri_buf[i].i_len < sizeof(xfs_disk_dquot_t)) { |
| xfs_alert(mp, |
| "XFS: dquot too small (%d) in %s.", |
| item->ri_buf[i].i_len, __func__); |
| goto next; |
| } |
| error = xfs_dqcheck(mp, item->ri_buf[i].i_addr, |
| -1, 0, XFS_QMOPT_DOWARN, |
| "dquot_buf_recover"); |
| if (error) |
| goto next; |
| } |
| |
| memcpy(xfs_buf_offset(bp, |
| (uint)bit << XFS_BLF_SHIFT), /* dest */ |
| item->ri_buf[i].i_addr, /* source */ |
| nbits<<XFS_BLF_SHIFT); /* length */ |
| next: |
| i++; |
| bit += nbits; |
| } |
| |
| /* Shouldn't be any more regions */ |
| ASSERT(i == item->ri_total); |
| |
| xlog_recover_validate_buf_type(mp, bp, buf_f, current_lsn); |
| } |
| |
| /* |
| * Perform a dquot buffer recovery. |
| * Simple algorithm: if we have found a QUOTAOFF log item of the same type |
| * (ie. USR or GRP), then just toss this buffer away; don't recover it. |
| * Else, treat it as a regular buffer and do recovery. |
| * |
| * Return false if the buffer was tossed and true if we recovered the buffer to |
| * indicate to the caller if the buffer needs writing. |
| */ |
| STATIC bool |
| xlog_recover_do_dquot_buffer( |
| struct xfs_mount *mp, |
| struct xlog *log, |
| struct xlog_recover_item *item, |
| struct xfs_buf *bp, |
| struct xfs_buf_log_format *buf_f) |
| { |
| uint type; |
| |
| trace_xfs_log_recover_buf_dquot_buf(log, buf_f); |
| |
| /* |
| * Filesystems are required to send in quota flags at mount time. |
| */ |
| if (!mp->m_qflags) |
| return false; |
| |
| type = 0; |
| if (buf_f->blf_flags & XFS_BLF_UDQUOT_BUF) |
| type |= XFS_DQ_USER; |
| if (buf_f->blf_flags & XFS_BLF_PDQUOT_BUF) |
| type |= XFS_DQ_PROJ; |
| if (buf_f->blf_flags & XFS_BLF_GDQUOT_BUF) |
| type |= XFS_DQ_GROUP; |
| /* |
| * This type of quotas was turned off, so ignore this buffer |
| */ |
| if (log->l_quotaoffs_flag & type) |
| return false; |
| |
| xlog_recover_do_reg_buffer(mp, item, bp, buf_f, NULLCOMMITLSN); |
| return true; |
| } |
| |
| /* |
| * This routine replays a modification made to a buffer at runtime. |
| * There are actually two types of buffer, regular and inode, which |
| * are handled differently. Inode buffers are handled differently |
| * in that we only recover a specific set of data from them, namely |
| * the inode di_next_unlinked fields. This is because all other inode |
| * data is actually logged via inode records and any data we replay |
| * here which overlaps that may be stale. |
| * |
| * When meta-data buffers are freed at run time we log a buffer item |
| * with the XFS_BLF_CANCEL bit set to indicate that previous copies |
| * of the buffer in the log should not be replayed at recovery time. |
| * This is so that if the blocks covered by the buffer are reused for |
| * file data before we crash we don't end up replaying old, freed |
| * meta-data into a user's file. |
| * |
| * To handle the cancellation of buffer log items, we make two passes |
| * over the log during recovery. During the first we build a table of |
| * those buffers which have been cancelled, and during the second we |
| * only replay those buffers which do not have corresponding cancel |
| * records in the table. See xlog_recover_buffer_pass[1,2] above |
| * for more details on the implementation of the table of cancel records. |
| */ |
| STATIC int |
| xlog_recover_buffer_pass2( |
| struct xlog *log, |
| struct list_head *buffer_list, |
| struct xlog_recover_item *item, |
| xfs_lsn_t current_lsn) |
| { |
| xfs_buf_log_format_t *buf_f = item->ri_buf[0].i_addr; |
| xfs_mount_t *mp = log->l_mp; |
| xfs_buf_t *bp; |
| int error; |
| uint buf_flags; |
| xfs_lsn_t lsn; |
| |
| /* |
| * In this pass we only want to recover all the buffers which have |
| * not been cancelled and are not cancellation buffers themselves. |
| */ |
| if (xlog_check_buffer_cancelled(log, buf_f->blf_blkno, |
| buf_f->blf_len, buf_f->blf_flags)) { |
| trace_xfs_log_recover_buf_cancel(log, buf_f); |
| return 0; |
| } |
| |
| trace_xfs_log_recover_buf_recover(log, buf_f); |
| |
| buf_flags = 0; |
| if (buf_f->blf_flags & XFS_BLF_INODE_BUF) |
| buf_flags |= XBF_UNMAPPED; |
| |
| bp = xfs_buf_read(mp->m_ddev_targp, buf_f->blf_blkno, buf_f->blf_len, |
| buf_flags, NULL); |
| if (!bp) |
| return -ENOMEM; |
| error = bp->b_error; |
| if (error) { |
| xfs_buf_ioerror_alert(bp, "xlog_recover_do..(read#1)"); |
| goto out_release; |
| } |
| |
| /* |
| * Recover the buffer only if we get an LSN from it and it's less than |
| * the lsn of the transaction we are replaying. |
| * |
| * Note that we have to be extremely careful of readahead here. |
| * Readahead does not attach verfiers to the buffers so if we don't |
| * actually do any replay after readahead because of the LSN we found |
| * in the buffer if more recent than that current transaction then we |
| * need to attach the verifier directly. Failure to do so can lead to |
| * future recovery actions (e.g. EFI and unlinked list recovery) can |
| * operate on the buffers and they won't get the verifier attached. This |
| * can lead to blocks on disk having the correct content but a stale |
| * CRC. |
| * |
| * It is safe to assume these clean buffers are currently up to date. |
| * If the buffer is dirtied by a later transaction being replayed, then |
| * the verifier will be reset to match whatever recover turns that |
| * buffer into. |
| */ |
| lsn = xlog_recover_get_buf_lsn(mp, bp); |
| if (lsn && lsn != -1 && XFS_LSN_CMP(lsn, current_lsn) >= 0) { |
| trace_xfs_log_recover_buf_skip(log, buf_f); |
| xlog_recover_validate_buf_type(mp, bp, buf_f, NULLCOMMITLSN); |
| goto out_release; |
| } |
| |
| if (buf_f->blf_flags & XFS_BLF_INODE_BUF) { |
| error = xlog_recover_do_inode_buffer(mp, item, bp, buf_f); |
| if (error) |
| goto out_release; |
| } else if (buf_f->blf_flags & |
| (XFS_BLF_UDQUOT_BUF|XFS_BLF_PDQUOT_BUF|XFS_BLF_GDQUOT_BUF)) { |
| bool dirty; |
| |
| dirty = xlog_recover_do_dquot_buffer(mp, log, item, bp, buf_f); |
| if (!dirty) |
| goto out_release; |
| } else { |
| xlog_recover_do_reg_buffer(mp, item, bp, buf_f, current_lsn); |
| } |
| |
| /* |
| * Perform delayed write on the buffer. Asynchronous writes will be |
| * slower when taking into account all the buffers to be flushed. |
| * |
| * Also make sure that only inode buffers with good sizes stay in |
| * the buffer cache. The kernel moves inodes in buffers of 1 block |
| * or mp->m_inode_cluster_size bytes, whichever is bigger. The inode |
| * buffers in the log can be a different size if the log was generated |
| * by an older kernel using unclustered inode buffers or a newer kernel |
| * running with a different inode cluster size. Regardless, if the |
| * the inode buffer size isn't MAX(blocksize, mp->m_inode_cluster_size) |
| * for *our* value of mp->m_inode_cluster_size, then we need to keep |
| * the buffer out of the buffer cache so that the buffer won't |
| * overlap with future reads of those inodes. |
| */ |
| if (XFS_DINODE_MAGIC == |
| be16_to_cpu(*((__be16 *)xfs_buf_offset(bp, 0))) && |
| (BBTOB(bp->b_io_length) != MAX(log->l_mp->m_sb.sb_blocksize, |
| (uint32_t)log->l_mp->m_inode_cluster_size))) { |
| xfs_buf_stale(bp); |
| error = xfs_bwrite(bp); |
| } else { |
| ASSERT(bp->b_target->bt_mount == mp); |
| bp->b_iodone = xlog_recover_iodone; |
| xfs_buf_delwri_queue(bp, buffer_list); |
| } |
| |
| out_release: |
| xfs_buf_relse(bp); |
| return error; |
| } |
| |
| /* |
| * Inode fork owner changes |
| * |
| * If we have been told that we have to reparent the inode fork, it's because an |
| * extent swap operation on a CRC enabled filesystem has been done and we are |
| * replaying it. We need to walk the BMBT of the appropriate fork and change the |
| * owners of it. |
| * |
| * The complexity here is that we don't have an inode context to work with, so |
| * after we've replayed the inode we need to instantiate one. This is where the |
| * fun begins. |
| * |
| * We are in the middle of log recovery, so we can't run transactions. That |
| * means we cannot use cache coherent inode instantiation via xfs_iget(), as |
| * that will result in the corresponding iput() running the inode through |
| * xfs_inactive(). If we've just replayed an inode core that changes the link |
| * count to zero (i.e. it's been unlinked), then xfs_inactive() will run |
| * transactions (bad!). |
| * |
| * So, to avoid this, we instantiate an inode directly from the inode core we've |
| * just recovered. We have the buffer still locked, and all we really need to |
| * instantiate is the inode core and the forks being modified. We can do this |
| * manually, then run the inode btree owner change, and then tear down the |
| * xfs_inode without having to run any transactions at all. |
| * |
| * Also, because we don't have a transaction context available here but need to |
| * gather all the buffers we modify for writeback so we pass the buffer_list |
| * instead for the operation to use. |
| */ |
| |
| STATIC int |
| xfs_recover_inode_owner_change( |
| struct xfs_mount *mp, |
| struct xfs_dinode *dip, |
| struct xfs_inode_log_format *in_f, |
| struct list_head *buffer_list) |
| { |
| struct xfs_inode *ip; |
| int error; |
| |
| ASSERT(in_f->ilf_fields & (XFS_ILOG_DOWNER|XFS_ILOG_AOWNER)); |
| |
| ip = xfs_inode_alloc(mp, in_f->ilf_ino); |
| if (!ip) |
| return -ENOMEM; |
| |
| /* instantiate the inode */ |
| xfs_inode_from_disk(ip, dip); |
| ASSERT(ip->i_d.di_version >= 3); |
| |
| error = xfs_iformat_fork(ip, dip); |
| if (error) |
| goto out_free_ip; |
| |
| |
| if (in_f->ilf_fields & XFS_ILOG_DOWNER) { |
| ASSERT(in_f->ilf_fields & XFS_ILOG_DBROOT); |
| error = xfs_bmbt_change_owner(NULL, ip, XFS_DATA_FORK, |
| ip->i_ino, buffer_list); |
| if (error) |
| goto out_free_ip; |
| } |
| |
| if (in_f->ilf_fields & XFS_ILOG_AOWNER) { |
| ASSERT(in_f->ilf_fields & XFS_ILOG_ABROOT); |
| error = xfs_bmbt_change_owner(NULL, ip, XFS_ATTR_FORK, |
| ip->i_ino, buffer_list); |
| if (error) |
| goto out_free_ip; |
| } |
| |
| out_free_ip: |
| xfs_inode_free(ip); |
| return error; |
| } |
| |
| STATIC int |
| xlog_recover_inode_pass2( |
| struct xlog *log, |
| struct list_head *buffer_list, |
| struct xlog_recover_item *item, |
| xfs_lsn_t current_lsn) |
| { |
| xfs_inode_log_format_t *in_f; |
| xfs_mount_t *mp = log->l_mp; |
| xfs_buf_t *bp; |
| xfs_dinode_t *dip; |
| int len; |
| char *src; |
| char *dest; |
| int error; |
| int attr_index; |
| uint fields; |
| struct xfs_log_dinode *ldip; |
| uint isize; |
| int need_free = 0; |
| |
| if (item->ri_buf[0].i_len == sizeof(xfs_inode_log_format_t)) { |
| in_f = item->ri_buf[0].i_addr; |
| } else { |
| in_f = kmem_alloc(sizeof(xfs_inode_log_format_t), KM_SLEEP); |
| need_free = 1; |
| error = xfs_inode_item_format_convert(&item->ri_buf[0], in_f); |
| if (error) |
| goto error; |
| } |
| |
| /* |
| * Inode buffers can be freed, look out for it, |
| * and do not replay the inode. |
| */ |
| if (xlog_check_buffer_cancelled(log, in_f->ilf_blkno, |
| in_f->ilf_len, 0)) { |
| error = 0; |
| trace_xfs_log_recover_inode_cancel(log, in_f); |
| goto error; |
| } |
| trace_xfs_log_recover_inode_recover(log, in_f); |
| |
| bp = xfs_buf_read(mp->m_ddev_targp, in_f->ilf_blkno, in_f->ilf_len, 0, |
| &xfs_inode_buf_ops); |
| if (!bp) { |
| error = -ENOMEM; |
| goto error; |
| } |
| error = bp->b_error; |
| if (error) { |
| xfs_buf_ioerror_alert(bp, "xlog_recover_do..(read#2)"); |
| goto out_release; |
| } |
| ASSERT(in_f->ilf_fields & XFS_ILOG_CORE); |
| dip = xfs_buf_offset(bp, in_f->ilf_boffset); |
| |
| /* |
| * Make sure the place we're flushing out to really looks |
| * like an inode! |
| */ |
| if (unlikely(dip->di_magic != cpu_to_be16(XFS_DINODE_MAGIC))) { |
| xfs_alert(mp, |
| "%s: Bad inode magic number, dip = 0x%p, dino bp = 0x%p, ino = %Ld", |
| __func__, dip, bp, in_f->ilf_ino); |
| XFS_ERROR_REPORT("xlog_recover_inode_pass2(1)", |
| XFS_ERRLEVEL_LOW, mp); |
| error = -EFSCORRUPTED; |
| goto out_release; |
| } |
| ldip = item->ri_buf[1].i_addr; |
| if (unlikely(ldip->di_magic != XFS_DINODE_MAGIC)) { |
| xfs_alert(mp, |
| "%s: Bad inode log record, rec ptr 0x%p, ino %Ld", |
| __func__, item, in_f->ilf_ino); |
| XFS_ERROR_REPORT("xlog_recover_inode_pass2(2)", |
| XFS_ERRLEVEL_LOW, mp); |
| error = -EFSCORRUPTED; |
| goto out_release; |
| } |
| |
| /* |
| * If the inode has an LSN in it, recover the inode only if it's less |
| * than the lsn of the transaction we are replaying. Note: we still |
| * need to replay an owner change even though the inode is more recent |
| * than the transaction as there is no guarantee that all the btree |
| * blocks are more recent than this transaction, too. |
| */ |
| if (dip->di_version >= 3) { |
| xfs_lsn_t lsn = be64_to_cpu(dip->di_lsn); |
| |
| if (lsn && lsn != -1 && XFS_LSN_CMP(lsn, current_lsn) >= 0) { |
| trace_xfs_log_recover_inode_skip(log, in_f); |
| error = 0; |
| goto out_owner_change; |
| } |
| } |
| |
| /* |
| * di_flushiter is only valid for v1/2 inodes. All changes for v3 inodes |
| * are transactional and if ordering is necessary we can determine that |
| * more accurately by the LSN field in the V3 inode core. Don't trust |
| * the inode versions we might be changing them here - use the |
| * superblock flag to determine whether we need to look at di_flushiter |
| * to skip replay when the on disk inode is newer than the log one |
| */ |
| if (!xfs_sb_version_hascrc(&mp->m_sb) && |
| ldip->di_flushiter < be16_to_cpu(dip->di_flushiter)) { |
| /* |
| * Deal with the wrap case, DI_MAX_FLUSH is less |
| * than smaller numbers |
| */ |
| if (be16_to_cpu(dip->di_flushiter) == DI_MAX_FLUSH && |
| ldip->di_flushiter < (DI_MAX_FLUSH >> 1)) { |
| /* do nothing */ |
| } else { |
| trace_xfs_log_recover_inode_skip(log, in_f); |
| error = 0; |
| goto out_release; |
| } |
| } |
| |
| /* Take the opportunity to reset the flush iteration count */ |
| ldip->di_flushiter = 0; |
| |
| if (unlikely(S_ISREG(ldip->di_mode))) { |
| if ((ldip->di_format != XFS_DINODE_FMT_EXTENTS) && |
| (ldip->di_format != XFS_DINODE_FMT_BTREE)) { |
| XFS_CORRUPTION_ERROR("xlog_recover_inode_pass2(3)", |
| XFS_ERRLEVEL_LOW, mp, ldip); |
| xfs_alert(mp, |
| "%s: Bad regular inode log record, rec ptr 0x%p, " |
| "ino ptr = 0x%p, ino bp = 0x%p, ino %Ld", |
| __func__, item, dip, bp, in_f->ilf_ino); |
| error = -EFSCORRUPTED; |
| goto out_release; |
| } |
| } else if (unlikely(S_ISDIR(ldip->di_mode))) { |
| if ((ldip->di_format != XFS_DINODE_FMT_EXTENTS) && |
| (ldip->di_format != XFS_DINODE_FMT_BTREE) && |
| (ldip->di_format != XFS_DINODE_FMT_LOCAL)) { |
| XFS_CORRUPTION_ERROR("xlog_recover_inode_pass2(4)", |
| XFS_ERRLEVEL_LOW, mp, ldip); |
| xfs_alert(mp, |
| "%s: Bad dir inode log record, rec ptr 0x%p, " |
| "ino ptr = 0x%p, ino bp = 0x%p, ino %Ld", |
| __func__, item, dip, bp, in_f->ilf_ino); |
| error = -EFSCORRUPTED; |
| goto out_release; |
| } |
| } |
| if (unlikely(ldip->di_nextents + ldip->di_anextents > ldip->di_nblocks)){ |
| XFS_CORRUPTION_ERROR("xlog_recover_inode_pass2(5)", |
| XFS_ERRLEVEL_LOW, mp, ldip); |
| xfs_alert(mp, |
| "%s: Bad inode log record, rec ptr 0x%p, dino ptr 0x%p, " |
| "dino bp 0x%p, ino %Ld, total extents = %d, nblocks = %Ld", |
| __func__, item, dip, bp, in_f->ilf_ino, |
| ldip->di_nextents + ldip->di_anextents, |
| ldip->di_nblocks); |
| error = -EFSCORRUPTED; |
| goto out_release; |
| } |
| if (unlikely(ldip->di_forkoff > mp->m_sb.sb_inodesize)) { |
| XFS_CORRUPTION_ERROR("xlog_recover_inode_pass2(6)", |
| XFS_ERRLEVEL_LOW, mp, ldip); |
| xfs_alert(mp, |
| "%s: Bad inode log record, rec ptr 0x%p, dino ptr 0x%p, " |
| "dino bp 0x%p, ino %Ld, forkoff 0x%x", __func__, |
| item, dip, bp, in_f->ilf_ino, ldip->di_forkoff); |
| error = -EFSCORRUPTED; |
| goto out_release; |
| } |
| isize = xfs_log_dinode_size(ldip->di_version); |
| if (unlikely(item->ri_buf[1].i_len > isize)) { |
| XFS_CORRUPTION_ERROR("xlog_recover_inode_pass2(7)", |
| XFS_ERRLEVEL_LOW, mp, ldip); |
| xfs_alert(mp, |
| "%s: Bad inode log record length %d, rec ptr 0x%p", |
| __func__, item->ri_buf[1].i_len, item); |
| error = -EFSCORRUPTED; |
| goto out_release; |
| } |
| |
| /* recover the log dinode inode into the on disk inode */ |
| xfs_log_dinode_to_disk(ldip, dip); |
| |
| /* the rest is in on-disk format */ |
| if (item->ri_buf[1].i_len > isize) { |
| memcpy((char *)dip + isize, |
| item->ri_buf[1].i_addr + isize, |
| item->ri_buf[1].i_len - isize); |
| } |
| |
| fields = in_f->ilf_fields; |
| switch (fields & (XFS_ILOG_DEV | XFS_ILOG_UUID)) { |
| case XFS_ILOG_DEV: |
| xfs_dinode_put_rdev(dip, in_f->ilf_u.ilfu_rdev); |
| break; |
| case XFS_ILOG_UUID: |
| memcpy(XFS_DFORK_DPTR(dip), |
| &in_f->ilf_u.ilfu_uuid, |
| sizeof(uuid_t)); |
| break; |
| } |
| |
| if (in_f->ilf_size == 2) |
| goto out_owner_change; |
| len = item->ri_buf[2].i_len; |
| src = item->ri_buf[2].i_addr; |
| ASSERT(in_f->ilf_size <= 4); |
| ASSERT((in_f->ilf_size == 3) || (fields & XFS_ILOG_AFORK)); |
| ASSERT(!(fields & XFS_ILOG_DFORK) || |
| (len == in_f->ilf_dsize)); |
| |
| switch (fields & XFS_ILOG_DFORK) { |
| case XFS_ILOG_DDATA: |
| case XFS_ILOG_DEXT: |
| memcpy(XFS_DFORK_DPTR(dip), src, len); |
| break; |
| |
| case XFS_ILOG_DBROOT: |
| xfs_bmbt_to_bmdr(mp, (struct xfs_btree_block *)src, len, |
| (xfs_bmdr_block_t *)XFS_DFORK_DPTR(dip), |
| XFS_DFORK_DSIZE(dip, mp)); |
| break; |
| |
| default: |
| /* |
| * There are no data fork flags set. |
| */ |
| ASSERT((fields & XFS_ILOG_DFORK) == 0); |
| break; |
| } |
| |
| /* |
| * If we logged any attribute data, recover it. There may or |
| * may not have been any other non-core data logged in this |
| * transaction. |
| */ |
| if (in_f->ilf_fields & XFS_ILOG_AFORK) { |
| if (in_f->ilf_fields & XFS_ILOG_DFORK) { |
| attr_index = 3; |
| } else { |
| attr_index = 2; |
| } |
| len = item->ri_buf[attr_index].i_len; |
| src = item->ri_buf[attr_index].i_addr; |
| ASSERT(len == in_f->ilf_asize); |
| |
| switch (in_f->ilf_fields & XFS_ILOG_AFORK) { |
| case XFS_ILOG_ADATA: |
| case XFS_ILOG_AEXT: |
| dest = XFS_DFORK_APTR(dip); |
| ASSERT(len <= XFS_DFORK_ASIZE(dip, mp)); |
| memcpy(dest, src, len); |
| break; |
| |
| case XFS_ILOG_ABROOT: |
| dest = XFS_DFORK_APTR(dip); |
| xfs_bmbt_to_bmdr(mp, (struct xfs_btree_block *)src, |
| len, (xfs_bmdr_block_t*)dest, |
| XFS_DFORK_ASIZE(dip, mp)); |
| break; |
| |
| default: |
| xfs_warn(log->l_mp, "%s: Invalid flag", __func__); |
| ASSERT(0); |
| error = -EIO; |
| goto out_release; |
| } |
| } |
| |
| out_owner_change: |
| if (in_f->ilf_fields & (XFS_ILOG_DOWNER|XFS_ILOG_AOWNER)) |
| error = xfs_recover_inode_owner_change(mp, dip, in_f, |
| buffer_list); |
| /* re-generate the checksum. */ |
| xfs_dinode_calc_crc(log->l_mp, dip); |
| |
| ASSERT(bp->b_target->bt_mount == mp); |
| bp->b_iodone = xlog_recover_iodone; |
| xfs_buf_delwri_queue(bp, buffer_list); |
| |
| out_release: |
| xfs_buf_relse(bp); |
| error: |
| if (need_free) |
| kmem_free(in_f); |
| return error; |
| } |
| |
| /* |
| * Recover QUOTAOFF records. We simply make a note of it in the xlog |
| * structure, so that we know not to do any dquot item or dquot buffer recovery, |
| * of that type. |
| */ |
| STATIC int |
| xlog_recover_quotaoff_pass1( |
| struct xlog *log, |
| struct xlog_recover_item *item) |
| { |
| xfs_qoff_logformat_t *qoff_f = item->ri_buf[0].i_addr; |
| ASSERT(qoff_f); |
| |
| /* |
| * The logitem format's flag tells us if this was user quotaoff, |
| * group/project quotaoff or both. |
| */ |
|