int
hammer_dedup_validate(hammer_dedup_cache_t dcp, int zone, int bytes,
void *data)
{
int error;
/*
* Zone validation
*/
if (HAMMER_ZONE_DECODE(dcp->data_offset) != zone)
return (0);
/*
* Block length validation
*/
if (dcp->bytes != bytes)
return (0);
/*
* Byte-by-byte data comparison
*
* The data we need for validation may already be present in the
* buffer cache in two flavours: vnode-based buffer or
* block-device-based buffer. In case vnode-based buffer wasn't
* there or if a non-blocking attempt to acquire it failed use
* device-based buffer (for large-zone data blocks it will
* generate a separate read).
*
* XXX vnode-based checking is not MP safe so when live-dedup
* is turned on we must always use the device buffer.
*/
#if 0
if (hammer_double_buffer) {
error = 1;
} else if (_vnode_validate(dcp, data, &error)) {
hammer_live_dedup_vnode_bcmps++;
return (1);
} else {
if (error == 3)
hammer_live_dedup_findblk_failures++;
}
/*
* If there was an error previously or if double buffering is
* enabled.
*/
if (error) {
if (_dev_validate(dcp, data, &error)) {
hammer_live_dedup_device_bcmps++;
return (1);
}
}
#endif
if (_dev_validate(dcp, data, &error)) {
hammer_live_dedup_device_bcmps++;
return (1);
}
return (0);
}
/*
* Convert a zone-3 undo offset into a zone-2 buffer offset.
*/
hammer_off_t
hammer_undo_lookup(hammer_mount_t hmp, hammer_off_t zone3_off, int *errorp)
{
hammer_volume_t root_volume;
hammer_blockmap_t undomap __debugvar;
hammer_off_t result_offset;
int i;
KKASSERT((zone3_off & HAMMER_OFF_ZONE_MASK) == HAMMER_ZONE_UNDO);
root_volume = hammer_get_root_volume(hmp, errorp);
if (*errorp)
return(0);
undomap = &hmp->blockmap[HAMMER_ZONE_UNDO_INDEX];
KKASSERT(HAMMER_ZONE_DECODE(undomap->alloc_offset) == HAMMER_ZONE_UNDO_INDEX);
KKASSERT(zone3_off < undomap->alloc_offset);
/*
* undo offsets[i] in zone-2 +
* big-block offset of zone-3 address
* which results zone-2 address
*/
i = (zone3_off & HAMMER_OFF_SHORT_MASK) / HAMMER_BIGBLOCK_SIZE;
result_offset = root_volume->ondisk->vol0_undo_array[i] +
(zone3_off & HAMMER_BIGBLOCK_MASK64);
hammer_rel_volume(root_volume, 0);
return(result_offset);
}
/*
* Convert a zone-3 undo offset into a zone-2 buffer offset.
*/
hammer_off_t
hammer_undo_lookup(hammer_mount_t hmp, hammer_off_t zone3_off, int *errorp)
{
hammer_volume_t root_volume;
hammer_blockmap_t undomap __debugvar;
hammer_off_t result_offset;
KKASSERT(hammer_is_zone_undo(zone3_off));
root_volume = hammer_get_root_volume(hmp, errorp);
if (*errorp)
return(0);
undomap = &hmp->blockmap[HAMMER_ZONE_UNDO_INDEX];
KKASSERT(HAMMER_ZONE_DECODE(undomap->alloc_offset) == HAMMER_ZONE_UNDO_INDEX);
KKASSERT(zone3_off < undomap->alloc_offset);
result_offset = hammer_xlate_to_undo(root_volume->ondisk, zone3_off);
hammer_rel_volume(root_volume, 0);
return(result_offset);
}
hammer_off_t
blockmap_lookup_save(hammer_off_t zone_offset,
hammer_blockmap_layer1_t save_layer1,
hammer_blockmap_layer2_t save_layer2,
int *errorp)
{
struct volume_info *root_volume = NULL;
hammer_volume_ondisk_t ondisk;
hammer_blockmap_t blockmap;
hammer_blockmap_t freemap;
hammer_blockmap_layer1_t layer1;
hammer_blockmap_layer2_t layer2;
struct buffer_info *buffer1 = NULL;
struct buffer_info *buffer2 = NULL;
hammer_off_t layer1_offset;
hammer_off_t layer2_offset;
hammer_off_t result_offset = HAMMER_OFF_BAD;;
int zone;
int error = 0;
if (save_layer1)
bzero(save_layer1, sizeof(*save_layer1));
if (save_layer2)
bzero(save_layer2, sizeof(*save_layer2));
zone = HAMMER_ZONE_DECODE(zone_offset);
if (zone <= HAMMER_ZONE_RAW_VOLUME_INDEX) {
error = -1;
goto done;
}
if (zone >= HAMMER_MAX_ZONES) {
error = -2;
goto done;
}
root_volume = get_root_volume();
ondisk = root_volume->ondisk;
blockmap = &ondisk->vol0_blockmap[zone];
/*
* Handle blockmap offset translations.
*/
if (hammer_is_index_record(zone)) {
result_offset = hammer_xlate_to_zone2(zone_offset);
} else if (zone == HAMMER_ZONE_UNDO_INDEX) {
if (zone_offset >= blockmap->alloc_offset) {
error = -3;
goto done;
}
result_offset = hammer_xlate_to_undo(ondisk, zone_offset);
} else {
/* assert(zone == HAMMER_ZONE_RAW_BUFFER_INDEX); */
result_offset = zone_offset;
}
/*
* The blockmap should match the requested zone (else the volume
* header is mashed).
*/
if (hammer_is_index_record(zone) &&
HAMMER_ZONE_DECODE(blockmap->alloc_offset) != zone) {
error = -4;
goto done;
}
/*
* Validate that the big-block is assigned to the zone. Also
* assign save_layer{1,2} if not NULL.
*/
freemap = &ondisk->vol0_blockmap[HAMMER_ZONE_FREEMAP_INDEX];
/*
* Dive layer 1.
*/
layer1_offset = freemap->phys_offset +
HAMMER_BLOCKMAP_LAYER1_OFFSET(result_offset);
layer1 = get_buffer_data(layer1_offset, &buffer1, 0);
if (layer1 == NULL) {
error = -5;
goto done;
}
if (layer1->phys_offset == HAMMER_BLOCKMAP_UNAVAIL) {
error = -6;
goto done;
}
if (save_layer1)
*save_layer1 = *layer1;
/*
* Dive layer 2, each entry represents a big-block.
*/
layer2_offset = layer1->phys_offset +
HAMMER_BLOCKMAP_LAYER2_OFFSET(result_offset);
layer2 = get_buffer_data(layer2_offset, &buffer2, 0);
if (layer2 == NULL) {
error = -7;
goto done;
}
if (layer2->zone != zone) {
error = -8;
goto done;
}
if (save_layer2)
*save_layer2 = *layer2;
done:
rel_buffer(buffer1);
rel_buffer(buffer2);
if (errorp)
*errorp = error;
return(result_offset);
}
/*
* Allocate a chunk of data out of a blockmap. This is a simplified
* version which uses next_offset as a simple allocation iterator.
*/
void *
alloc_blockmap(int zone, int bytes, hammer_off_t *result_offp,
struct buffer_info **bufferp)
{
struct volume_info *volume;
hammer_blockmap_t blockmap;
hammer_blockmap_t freemap;
struct buffer_info *buffer1 = NULL;
struct buffer_info *buffer2 = NULL;
hammer_blockmap_layer1_t layer1;
hammer_blockmap_layer2_t layer2;
hammer_off_t tmp_offset;
hammer_off_t layer1_offset;
hammer_off_t layer2_offset;
hammer_off_t block_offset;
void *ptr;
volume = get_root_volume();
blockmap = &volume->ondisk->vol0_blockmap[zone];
freemap = &volume->ondisk->vol0_blockmap[HAMMER_ZONE_FREEMAP_INDEX];
assert(HAMMER_ZONE_DECODE(blockmap->next_offset) == zone);
/*
* Alignment and buffer-boundary issues. If the allocation would
* cross a buffer boundary we have to skip to the next buffer.
*/
bytes = HAMMER_DATA_DOALIGN(bytes);
assert(bytes > 0 && bytes <= HAMMER_BUFSIZE); /* not HAMMER_XBUFSIZE */
assert(hammer_is_index_record(zone));
again:
assert(blockmap->next_offset != HAMMER_ZONE_ENCODE(zone + 1, 0));
tmp_offset = blockmap->next_offset + bytes - 1;
if ((blockmap->next_offset ^ tmp_offset) & ~HAMMER_BUFMASK64) {
blockmap->next_offset = tmp_offset & ~HAMMER_BUFMASK64;
}
block_offset = blockmap->next_offset & HAMMER_BIGBLOCK_MASK;
/*
* Dive layer 1.
*/
layer1_offset = freemap->phys_offset +
HAMMER_BLOCKMAP_LAYER1_OFFSET(blockmap->next_offset);
layer1 = get_buffer_data(layer1_offset, &buffer1, 0);
assert(layer1->phys_offset != HAMMER_BLOCKMAP_UNAVAIL);
assert(!(block_offset == 0 && layer1->blocks_free == 0));
/*
* Dive layer 2, each entry represents a big-block.
*/
layer2_offset = layer1->phys_offset +
HAMMER_BLOCKMAP_LAYER2_OFFSET(blockmap->next_offset);
layer2 = get_buffer_data(layer2_offset, &buffer2, 0);
if (layer2->zone == HAMMER_ZONE_UNAVAIL_INDEX)
errx(1, "alloc_blockmap: layer2 ran out of space!");
/*
* If we are entering a new big-block assign ownership to our
* zone. If the big-block is owned by another zone skip it.
*/
if (layer2->zone == 0) {
--layer1->blocks_free;
hammer_crc_set_layer1(layer1);
layer2->zone = zone;
--volume->ondisk->vol0_stat_freebigblocks;
assert(layer2->bytes_free == HAMMER_BIGBLOCK_SIZE);
assert(layer2->append_off == 0);
}
if (layer2->zone != zone) {
blockmap->next_offset =
HAMMER_ZONE_LAYER2_NEXT_OFFSET(blockmap->next_offset);
goto again;
}
assert(layer2->append_off == block_offset);
layer2->bytes_free -= bytes;
*result_offp = blockmap->next_offset;
blockmap->next_offset += bytes;
layer2->append_off = (int)blockmap->next_offset & HAMMER_BIGBLOCK_MASK;
hammer_crc_set_layer2(layer2);
ptr = get_buffer_data(*result_offp, bufferp, 0);
(*bufferp)->cache.modified = 1;
buffer1->cache.modified = 1;
buffer2->cache.modified = 1;
rel_buffer(buffer1);
rel_buffer(buffer2);
return(ptr);
}
