Merge branch 'stable/late-swiotlb.v3.3' into stable/for-linus-3.7

[cascardo/linux.git] / drivers / md / dm-stripe.c

diff --git a/drivers/md/dm-stripe.c b/drivers/md/dm-stripe.c
index 183db5d..a087bf2 100644 (file)
--- a/drivers/md/dm-stripe.c
+++ b/drivers/md/dm-stripe.c
@@ -26,14 +26,12 @@ struct stripe {
 struct stripe_c {
        uint32_t stripes;
        int stripes_shift;
-       sector_t stripes_mask;
 
        /* The size of this target / num. stripes */
        sector_t stripe_width;
 
-       /* stripe chunk size */
-       uint32_t chunk_shift;
-       sector_t chunk_mask;
+       uint32_t chunk_size;
+       int chunk_size_shift;
 
        /* Needed for handling events */
        struct dm_target *ti;
@@ -91,7 +89,7 @@ static int get_stripe(struct dm_target *ti, struct stripe_c *sc,
 
 /*
  * Construct a striped mapping.
- * <number of stripes> <chunk size (2^^n)> [<dev_path> <offset>]+
+ * <number of stripes> <chunk size> [<dev_path> <offset>]+
  */
 static int stripe_ctr(struct dm_target *ti, unsigned int argc, char **argv)
 {
@@ -112,27 +110,18 @@ static int stripe_ctr(struct dm_target *ti, unsigned int argc, char **argv)
                return -EINVAL;
        }
 
-       if (kstrtouint(argv[1], 10, &chunk_size)) {
+       if (kstrtouint(argv[1], 10, &chunk_size) || !chunk_size) {
                ti->error = "Invalid chunk_size";
                return -EINVAL;
        }
 
-       /*
-        * chunk_size is a power of two
-        */
-       if (!is_power_of_2(chunk_size) ||
-           (chunk_size < (PAGE_SIZE >> SECTOR_SHIFT))) {
-               ti->error = "Invalid chunk size";
-               return -EINVAL;
-       }
-
-       if (ti->len & (chunk_size - 1)) {
+       width = ti->len;
+       if (sector_div(width, chunk_size)) {
                ti->error = "Target length not divisible by "
                    "chunk size";
                return -EINVAL;
        }
 
-       width = ti->len;
        if (sector_div(width, stripes)) {
                ti->error = "Target length not divisible by "
                    "number of stripes";
@@ -164,17 +153,21 @@ static int stripe_ctr(struct dm_target *ti, unsigned int argc, char **argv)
 
        if (stripes & (stripes - 1))
                sc->stripes_shift = -1;
-       else {
-               sc->stripes_shift = ffs(stripes) - 1;
-               sc->stripes_mask = ((sector_t) stripes) - 1;
-       }
+       else
+               sc->stripes_shift = __ffs(stripes);
+
+       r = dm_set_target_max_io_len(ti, chunk_size);
+       if (r)
+               return r;
 
-       ti->split_io = chunk_size;
        ti->num_flush_requests = stripes;
        ti->num_discard_requests = stripes;
 
-       sc->chunk_shift = ffs(chunk_size) - 1;
-       sc->chunk_mask = ((sector_t) chunk_size) - 1;
+       sc->chunk_size = chunk_size;
+       if (chunk_size & (chunk_size - 1))
+               sc->chunk_size_shift = -1;
+       else
+               sc->chunk_size_shift = __ffs(chunk_size);
 
        /*
         * Get the stripe destinations.
@@ -213,17 +206,29 @@ static void stripe_dtr(struct dm_target *ti)
 static void stripe_map_sector(struct stripe_c *sc, sector_t sector,
                              uint32_t *stripe, sector_t *result)
 {
-       sector_t offset = dm_target_offset(sc->ti, sector);
-       sector_t chunk = offset >> sc->chunk_shift;
+       sector_t chunk = dm_target_offset(sc->ti, sector);
+       sector_t chunk_offset;
+
+       if (sc->chunk_size_shift < 0)
+               chunk_offset = sector_div(chunk, sc->chunk_size);
+       else {
+               chunk_offset = chunk & (sc->chunk_size - 1);
+               chunk >>= sc->chunk_size_shift;
+       }
 
        if (sc->stripes_shift < 0)
                *stripe = sector_div(chunk, sc->stripes);
        else {
-               *stripe = chunk & sc->stripes_mask;
+               *stripe = chunk & (sc->stripes - 1);
                chunk >>= sc->stripes_shift;
        }
 
-       *result = (chunk << sc->chunk_shift) | (offset & sc->chunk_mask);
+       if (sc->chunk_size_shift < 0)
+               chunk *= sc->chunk_size;
+       else
+               chunk <<= sc->chunk_size_shift;
+
+       *result = chunk + chunk_offset;
 }
 
 static void stripe_map_range_sector(struct stripe_c *sc, sector_t sector,
@@ -234,9 +239,16 @@ static void stripe_map_range_sector(struct stripe_c *sc, sector_t sector,
        stripe_map_sector(sc, sector, &stripe, result);
        if (stripe == target_stripe)
                return;
-       *result &= ~sc->chunk_mask;                     /* round down */
+
+       /* round down */
+       sector = *result;
+       if (sc->chunk_size_shift < 0)
+               *result -= sector_div(sector, sc->chunk_size);
+       else
+               *result = sector & ~(sector_t)(sc->chunk_size - 1);
+
        if (target_stripe < stripe)
-               *result += sc->chunk_mask + 1;          /* next chunk */
+               *result += sc->chunk_size;              /* next chunk */
 }
 
 static int stripe_map_discard(struct stripe_c *sc, struct bio *bio,
@@ -299,8 +311,8 @@ static int stripe_map(struct dm_target *ti, struct bio *bio,
  *
  */
 
-static int stripe_status(struct dm_target *ti,
-                        status_type_t type, char *result, unsigned int maxlen)
+static int stripe_status(struct dm_target *ti, status_type_t type,
+                        unsigned status_flags, char *result, unsigned maxlen)
 {
        struct stripe_c *sc = (struct stripe_c *) ti->private;
        char buffer[sc->stripes + 1];
@@ -321,7 +333,7 @@ static int stripe_status(struct dm_target *ti,
 
        case STATUSTYPE_TABLE:
                DMEMIT("%d %llu", sc->stripes,
-                       (unsigned long long)sc->chunk_mask + 1);
+                       (unsigned long long)sc->chunk_size);
                for (i = 0; i < sc->stripes; i++)
                        DMEMIT(" %s %llu", sc->stripe[i].dev->name,
                            (unsigned long long)sc->stripe[i].physical_start);
@@ -388,7 +400,7 @@ static void stripe_io_hints(struct dm_target *ti,
                            struct queue_limits *limits)
 {
        struct stripe_c *sc = ti->private;
-       unsigned chunk_size = (sc->chunk_mask + 1) << 9;
+       unsigned chunk_size = sc->chunk_size << SECTOR_SHIFT;
 
        blk_limits_io_min(limits, chunk_size);
        blk_limits_io_opt(limits, chunk_size * sc->stripes);
@@ -416,7 +428,7 @@ static int stripe_merge(struct dm_target *ti, struct bvec_merge_data *bvm,
 
 static struct target_type stripe_target = {
        .name   = "striped",
-       .version = {1, 4, 0},
+       .version = {1, 5, 0},
        .module = THIS_MODULE,
        .ctr    = stripe_ctr,
        .dtr    = stripe_dtr,