diff options
| -rw-r--r-- | Documentation/device-mapper/writecache.txt | 2 | ||||
| -rw-r--r-- | drivers/md/dm-writecache.c | 43 |
2 files changed, 31 insertions, 14 deletions
diff --git a/Documentation/device-mapper/writecache.txt b/Documentation/device-mapper/writecache.txt index 4424fa2c67d7..01532b3008ae 100644 --- a/Documentation/device-mapper/writecache.txt +++ b/Documentation/device-mapper/writecache.txt @@ -15,6 +15,8 @@ Constructor parameters: size) 5. the number of optional parameters (the parameters with an argument count as two) + start_sector n (default: 0) + offset from the start of cache device in 512-byte sectors high_watermark n (default: 50) start writeback when the number of used blocks reach this watermark diff --git a/drivers/md/dm-writecache.c b/drivers/md/dm-writecache.c index 07ea6a48aac6..87107c995cb5 100644 --- a/drivers/md/dm-writecache.c +++ b/drivers/md/dm-writecache.c @@ -136,6 +136,7 @@ struct dm_writecache { struct dm_target *ti; struct dm_dev *dev; struct dm_dev *ssd_dev; + sector_t start_sector; void *memory_map; uint64_t memory_map_size; size_t metadata_sectors; @@ -293,6 +294,10 @@ static int persistent_memory_claim(struct dm_writecache *wc) } dax_read_unlock(id); + + wc->memory_map += (size_t)wc->start_sector << SECTOR_SHIFT; + wc->memory_map_size -= (size_t)wc->start_sector << SECTOR_SHIFT; + return 0; err3: kvfree(pages); @@ -311,7 +316,7 @@ static int persistent_memory_claim(struct dm_writecache *wc) static void persistent_memory_release(struct dm_writecache *wc) { if (wc->memory_vmapped) - vunmap(wc->memory_map); + vunmap(wc->memory_map - ((size_t)wc->start_sector << SECTOR_SHIFT)); } static struct page *persistent_memory_page(void *addr) @@ -359,7 +364,7 @@ static void *memory_data(struct dm_writecache *wc, struct wc_entry *e) static sector_t cache_sector(struct dm_writecache *wc, struct wc_entry *e) { - return wc->metadata_sectors + + return wc->start_sector + wc->metadata_sectors + ((sector_t)e->index << (wc->block_size_bits - SECTOR_SHIFT)); } @@ -471,6 +476,7 @@ static void ssd_commit_flushed(struct dm_writecache *wc) if (unlikely(region.sector + region.count > wc->metadata_sectors)) region.count = wc->metadata_sectors - region.sector; + region.sector += wc->start_sector; atomic_inc(&endio.count); req.bi_op = REQ_OP_WRITE; req.bi_op_flags = REQ_SYNC; @@ -1946,14 +1952,6 @@ static int writecache_ctr(struct dm_target *ti, unsigned argc, char **argv) } wc->memory_map_size = i_size_read(wc->ssd_dev->bdev->bd_inode); - if (WC_MODE_PMEM(wc)) { - r = persistent_memory_claim(wc); - if (r) { - ti->error = "Unable to map persistent memory for cache"; - goto bad; - } - } - /* * Parse the cache block size */ @@ -1982,7 +1980,16 @@ static int writecache_ctr(struct dm_target *ti, unsigned argc, char **argv) while (opt_params) { string = dm_shift_arg(&as), opt_params--; - if (!strcasecmp(string, "high_watermark") && opt_params >= 1) { + if (!strcasecmp(string, "start_sector") && opt_params >= 1) { + unsigned long long start_sector; + string = dm_shift_arg(&as), opt_params--; + if (sscanf(string, "%llu%c", &start_sector, &dummy) != 1) + goto invalid_optional; + wc->start_sector = start_sector; + if (wc->start_sector != start_sector || + wc->start_sector >= wc->memory_map_size >> SECTOR_SHIFT) + goto invalid_optional; + } else if (!strcasecmp(string, "high_watermark") && opt_params >= 1) { string = dm_shift_arg(&as), opt_params--; if (sscanf(string, "%d%c", &high_wm_percent, &dummy) != 1) goto invalid_optional; @@ -2039,12 +2046,20 @@ invalid_optional: goto bad; } - if (!WC_MODE_PMEM(wc)) { + if (WC_MODE_PMEM(wc)) { + r = persistent_memory_claim(wc); + if (r) { + ti->error = "Unable to map persistent memory for cache"; + goto bad; + } + } else { struct dm_io_region region; struct dm_io_request req; size_t n_blocks, n_metadata_blocks; uint64_t n_bitmap_bits; + wc->memory_map_size -= (uint64_t)wc->start_sector << SECTOR_SHIFT; + bio_list_init(&wc->flush_list); wc->flush_thread = kthread_create(writecache_flush_thread, wc, "dm_writecache_flush"); if (IS_ERR(wc->flush_thread)) { @@ -2097,7 +2112,7 @@ invalid_optional: } region.bdev = wc->ssd_dev->bdev; - region.sector = 0; + region.sector = wc->start_sector; region.count = wc->metadata_sectors; req.bi_op = REQ_OP_READ; req.bi_op_flags = REQ_SYNC; @@ -2265,7 +2280,7 @@ static void writecache_status(struct dm_target *ti, status_type_t type, static struct target_type writecache_target = { .name = "writecache", - .version = {1, 0, 0}, + .version = {1, 1, 0}, .module = THIS_MODULE, .ctr = writecache_ctr, .dtr = writecache_dtr, |