diff options
Diffstat (limited to 'drivers/md/dm-log.c')
-rw-r--r-- | drivers/md/dm-log.c | 157 |
1 files changed, 73 insertions, 84 deletions
diff --git a/drivers/md/dm-log.c b/drivers/md/dm-log.c index d73779a4241..64b764bd02c 100644 --- a/drivers/md/dm-log.c +++ b/drivers/md/dm-log.c @@ -12,6 +12,8 @@ #include "dm-log.h" #include "dm-io.h" +#define DM_MSG_PREFIX "mirror log" + static LIST_HEAD(_log_types); static DEFINE_SPINLOCK(_lock); @@ -155,8 +157,6 @@ struct log_c { struct io_region header_location; struct log_header *disk_header; - - struct io_region bits_location; }; /* @@ -241,43 +241,21 @@ static inline int write_header(struct log_c *log) } /*---------------------------------------------------------------- - * Bits IO - *--------------------------------------------------------------*/ -static int read_bits(struct log_c *log) -{ - int r; - unsigned long ebits; - - r = dm_io_sync_vm(1, &log->bits_location, READ, - log->clean_bits, &ebits); - if (r) - return r; - - return 0; -} - -static int write_bits(struct log_c *log) -{ - unsigned long ebits; - return dm_io_sync_vm(1, &log->bits_location, WRITE, - log->clean_bits, &ebits); -} - -/*---------------------------------------------------------------- * core log constructor/destructor * * argv contains region_size followed optionally by [no]sync *--------------------------------------------------------------*/ #define BYTE_SHIFT 3 -static int core_ctr(struct dirty_log *log, struct dm_target *ti, - unsigned int argc, char **argv) +static int create_log_context(struct dirty_log *log, struct dm_target *ti, + unsigned int argc, char **argv, + struct dm_dev *dev) { enum sync sync = DEFAULTSYNC; struct log_c *lc; uint32_t region_size; unsigned int region_count; - size_t bitset_size; + size_t bitset_size, buf_size; if (argc < 1 || argc > 2) { DMWARN("wrong number of arguments to mirror log"); @@ -319,22 +297,53 @@ static int core_ctr(struct dirty_log *log, struct dm_target *ti, * Work out how many "unsigned long"s we need to hold the bitset. */ bitset_size = dm_round_up(region_count, - sizeof(unsigned long) << BYTE_SHIFT); + sizeof(*lc->clean_bits) << BYTE_SHIFT); bitset_size >>= BYTE_SHIFT; - lc->bitset_uint32_count = bitset_size / 4; - lc->clean_bits = vmalloc(bitset_size); - if (!lc->clean_bits) { - DMWARN("couldn't allocate clean bitset"); - kfree(lc); - return -ENOMEM; + lc->bitset_uint32_count = bitset_size / sizeof(*lc->clean_bits); + + /* + * Disk log? + */ + if (!dev) { + lc->clean_bits = vmalloc(bitset_size); + if (!lc->clean_bits) { + DMWARN("couldn't allocate clean bitset"); + kfree(lc); + return -ENOMEM; + } + lc->disk_header = NULL; + } else { + lc->log_dev = dev; + lc->header_location.bdev = lc->log_dev->bdev; + lc->header_location.sector = 0; + + /* + * Buffer holds both header and bitset. + */ + buf_size = dm_round_up((LOG_OFFSET << SECTOR_SHIFT) + + bitset_size, ti->limits.hardsect_size); + lc->header_location.count = buf_size >> SECTOR_SHIFT; + + lc->disk_header = vmalloc(buf_size); + if (!lc->disk_header) { + DMWARN("couldn't allocate disk log buffer"); + kfree(lc); + return -ENOMEM; + } + + lc->clean_bits = (void *)lc->disk_header + + (LOG_OFFSET << SECTOR_SHIFT); } + memset(lc->clean_bits, -1, bitset_size); lc->sync_bits = vmalloc(bitset_size); if (!lc->sync_bits) { DMWARN("couldn't allocate sync bitset"); - vfree(lc->clean_bits); + if (!dev) + vfree(lc->clean_bits); + vfree(lc->disk_header); kfree(lc); return -ENOMEM; } @@ -345,25 +354,40 @@ static int core_ctr(struct dirty_log *log, struct dm_target *ti, if (!lc->recovering_bits) { DMWARN("couldn't allocate sync bitset"); vfree(lc->sync_bits); - vfree(lc->clean_bits); + if (!dev) + vfree(lc->clean_bits); + vfree(lc->disk_header); kfree(lc); return -ENOMEM; } memset(lc->recovering_bits, 0, bitset_size); lc->sync_search = 0; log->context = lc; + return 0; } -static void core_dtr(struct dirty_log *log) +static int core_ctr(struct dirty_log *log, struct dm_target *ti, + unsigned int argc, char **argv) +{ + return create_log_context(log, ti, argc, argv, NULL); +} + +static void destroy_log_context(struct log_c *lc) { - struct log_c *lc = (struct log_c *) log->context; - vfree(lc->clean_bits); vfree(lc->sync_bits); vfree(lc->recovering_bits); kfree(lc); } +static void core_dtr(struct dirty_log *log) +{ + struct log_c *lc = (struct log_c *) log->context; + + vfree(lc->clean_bits); + destroy_log_context(lc); +} + /*---------------------------------------------------------------- * disk log constructor/destructor * @@ -373,8 +397,6 @@ static int disk_ctr(struct dirty_log *log, struct dm_target *ti, unsigned int argc, char **argv) { int r; - size_t size; - struct log_c *lc; struct dm_dev *dev; if (argc < 2 || argc > 3) { @@ -387,49 +409,22 @@ static int disk_ctr(struct dirty_log *log, struct dm_target *ti, if (r) return r; - r = core_ctr(log, ti, argc - 1, argv + 1); + r = create_log_context(log, ti, argc - 1, argv + 1, dev); if (r) { dm_put_device(ti, dev); return r; } - lc = (struct log_c *) log->context; - lc->log_dev = dev; - - /* setup the disk header fields */ - lc->header_location.bdev = lc->log_dev->bdev; - lc->header_location.sector = 0; - lc->header_location.count = 1; - - /* - * We can't read less than this amount, even though we'll - * not be using most of this space. - */ - lc->disk_header = vmalloc(1 << SECTOR_SHIFT); - if (!lc->disk_header) - goto bad; - - /* setup the disk bitset fields */ - lc->bits_location.bdev = lc->log_dev->bdev; - lc->bits_location.sector = LOG_OFFSET; - - size = dm_round_up(lc->bitset_uint32_count * sizeof(uint32_t), - 1 << SECTOR_SHIFT); - lc->bits_location.count = size >> SECTOR_SHIFT; return 0; - - bad: - dm_put_device(ti, lc->log_dev); - core_dtr(log); - return -ENOMEM; } static void disk_dtr(struct dirty_log *log) { struct log_c *lc = (struct log_c *) log->context; + dm_put_device(lc->ti, lc->log_dev); vfree(lc->disk_header); - core_dtr(log); + destroy_log_context(lc); } static int count_bits32(uint32_t *addr, unsigned size) @@ -454,12 +449,7 @@ static int disk_resume(struct dirty_log *log) if (r) return r; - /* read the bits */ - r = read_bits(lc); - if (r) - return r; - - /* set or clear any new bits */ + /* set or clear any new bits -- device has grown */ if (lc->sync == NOSYNC) for (i = lc->header.nr_regions; i < lc->region_count; i++) /* FIXME: amazingly inefficient */ @@ -469,15 +459,14 @@ static int disk_resume(struct dirty_log *log) /* FIXME: amazingly inefficient */ log_clear_bit(lc, lc->clean_bits, i); + /* clear any old bits -- device has shrunk */ + for (i = lc->region_count; i % (sizeof(*lc->clean_bits) << BYTE_SHIFT); i++) + log_clear_bit(lc, lc->clean_bits, i); + /* copy clean across to sync */ memcpy(lc->sync_bits, lc->clean_bits, size); lc->sync_count = count_bits32(lc->clean_bits, lc->bitset_uint32_count); - /* write the bits */ - r = write_bits(lc); - if (r) - return r; - /* set the correct number of regions in the header */ lc->header.nr_regions = lc->region_count; @@ -518,7 +507,7 @@ static int disk_flush(struct dirty_log *log) if (!lc->touched) return 0; - r = write_bits(lc); + r = write_header(lc); if (!r) lc->touched = 0; |