[PATCH] dm mirror log: sector size fix

On-disk logs for dm-mirror devices are currently hard-coded to use 512 byte
hard-sector-sizes.  This patch fixes dm-log so it will work with devices with
non-512-byte hard-sector-sizes.

To maintain full compatibility, instead of moving the clean-bits bitset to a
bitset, and enlarges the disk-header buffer to encompass both the header and
the bitset.  The I/O routines for the bitset are removed, and the I/O routines
for the disk-header now also read/write the bitset.

Signed-off-by: Kevin Corry <kevcorry@us.ibm.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Kevin Corry 2006-06-26 00:27:28 -07:00 committed by Linus Torvalds
parent 143535396c
commit 702ca6f0be
2 changed files with 20 additions and 50 deletions

View file

@ -155,8 +155,6 @@ struct log_c {
struct io_region header_location;
struct log_header *disk_header;
struct io_region bits_location;
};
/*
@ -240,29 +238,6 @@ static inline int write_header(struct log_c *log)
log->disk_header, &ebits);
}
/*----------------------------------------------------------------
* 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
*
@ -373,9 +348,10 @@ static int disk_ctr(struct dirty_log *log, struct dm_target *ti,
unsigned int argc, char **argv)
{
int r;
size_t size;
size_t size, bitset_size;
struct log_c *lc;
struct dm_dev *dev;
uint32_t *clean_bits;
if (argc < 2 || argc > 3) {
DMWARN("wrong number of arguments to disk mirror log");
@ -399,23 +375,26 @@ static int disk_ctr(struct dirty_log *log, struct dm_target *ti,
/* 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);
/* Include both the header and the bitset in one buffer. */
bitset_size = lc->bitset_uint32_count * sizeof(uint32_t);
size = dm_round_up((LOG_OFFSET << SECTOR_SHIFT) + bitset_size,
ti->limits.hardsect_size);
lc->header_location.count = size >> SECTOR_SHIFT;
lc->disk_header = vmalloc(size);
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;
/*
* Deallocate the clean_bits buffer that was allocated in core_ctr()
* and point it at the appropriate place in the disk_header buffer.
*/
clean_bits = lc->clean_bits;
lc->clean_bits = (void *)lc->disk_header + (LOG_OFFSET << SECTOR_SHIFT);
memcpy(lc->clean_bits, clean_bits, bitset_size);
vfree(clean_bits);
size = dm_round_up(lc->bitset_uint32_count * sizeof(uint32_t),
1 << SECTOR_SHIFT);
lc->bits_location.count = size >> SECTOR_SHIFT;
return 0;
bad:
@ -429,6 +408,7 @@ 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);
lc->clean_bits = NULL;
core_dtr(log);
}
@ -454,11 +434,6 @@ 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 */
if (lc->sync == NOSYNC)
for (i = lc->header.nr_regions; i < lc->region_count; i++)
@ -473,11 +448,6 @@ static int disk_resume(struct dirty_log *log)
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 +488,7 @@ 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;

View file

@ -1220,7 +1220,7 @@ static int mirror_status(struct dm_target *ti, status_type_t type,
static struct target_type mirror_target = {
.name = "mirror",
.version = {1, 0, 1},
.version = {1, 0, 2},
.module = THIS_MODULE,
.ctr = mirror_ctr,
.dtr = mirror_dtr,