diff options
Diffstat (limited to 'drivers/md/dm-switch.c')
| -rw-r--r-- | drivers/md/dm-switch.c | 67 |
1 files changed, 60 insertions, 7 deletions
diff --git a/drivers/md/dm-switch.c b/drivers/md/dm-switch.c index 09a688b3d48c..50fca469cafd 100644 --- a/drivers/md/dm-switch.c +++ b/drivers/md/dm-switch.c @@ -137,13 +137,23 @@ static void switch_get_position(struct switch_ctx *sctx, unsigned long region_nr *bit *= sctx->region_table_entry_bits; } +static unsigned switch_region_table_read(struct switch_ctx *sctx, unsigned long region_nr) +{ + unsigned long region_index; + unsigned bit; + + switch_get_position(sctx, region_nr, ®ion_index, &bit); + + return (ACCESS_ONCE(sctx->region_table[region_index]) >> bit) & + ((1 << sctx->region_table_entry_bits) - 1); +} + /* * Find which path to use at given offset. */ static unsigned switch_get_path_nr(struct switch_ctx *sctx, sector_t offset) { - unsigned long region_index; - unsigned bit, path_nr; + unsigned path_nr; sector_t p; p = offset; @@ -152,9 +162,7 @@ static unsigned switch_get_path_nr(struct switch_ctx *sctx, sector_t offset) else sector_div(p, sctx->region_size); - switch_get_position(sctx, p, ®ion_index, &bit); - path_nr = (ACCESS_ONCE(sctx->region_table[region_index]) >> bit) & - ((1 << sctx->region_table_entry_bits) - 1); + path_nr = switch_region_table_read(sctx, p); /* This can only happen if the processor uses non-atomic stores. */ if (unlikely(path_nr >= sctx->nr_paths)) @@ -363,7 +371,7 @@ static __always_inline unsigned long parse_hex(const char **string) } static int process_set_region_mappings(struct switch_ctx *sctx, - unsigned argc, char **argv) + unsigned argc, char **argv) { unsigned i; unsigned long region_index = 0; @@ -372,6 +380,51 @@ static int process_set_region_mappings(struct switch_ctx *sctx, unsigned long path_nr; const char *string = argv[i]; + if ((*string & 0xdf) == 'R') { + unsigned long cycle_length, num_write; + + string++; + if (unlikely(*string == ',')) { + DMWARN("invalid set_region_mappings argument: '%s'", argv[i]); + return -EINVAL; + } + cycle_length = parse_hex(&string); + if (unlikely(*string != ',')) { + DMWARN("invalid set_region_mappings argument: '%s'", argv[i]); + return -EINVAL; + } + string++; + if (unlikely(!*string)) { + DMWARN("invalid set_region_mappings argument: '%s'", argv[i]); + return -EINVAL; + } + num_write = parse_hex(&string); + if (unlikely(*string)) { + DMWARN("invalid set_region_mappings argument: '%s'", argv[i]); + return -EINVAL; + } + + if (unlikely(!cycle_length) || unlikely(cycle_length - 1 > region_index)) { + DMWARN("invalid set_region_mappings cycle length: %lu > %lu", + cycle_length - 1, region_index); + return -EINVAL; + } + if (unlikely(region_index + num_write < region_index) || + unlikely(region_index + num_write >= sctx->nr_regions)) { + DMWARN("invalid set_region_mappings region number: %lu + %lu >= %lu", + region_index, num_write, sctx->nr_regions); + return -EINVAL; + } + + while (num_write--) { + region_index++; + path_nr = switch_region_table_read(sctx, region_index - cycle_length); + switch_region_table_write(sctx, region_index, path_nr); + } + + continue; + } + if (*string == ':') region_index++; else { @@ -500,7 +553,7 @@ static int switch_iterate_devices(struct dm_target *ti, static struct target_type switch_target = { .name = "switch", - .version = {1, 0, 0}, + .version = {1, 1, 0}, .module = THIS_MODULE, .ctr = switch_ctr, .dtr = switch_dtr, |