mmc: core: Fix size overflow for mmc partitions

With large eMMC cards, it is possible to create general purpose
partitions that are bigger than 4GB.  The size member of the mmc_part
struct is only an unsigned int which overflows for gp partitions larger
than 4GB.  Change this to a u64 to handle the overflow.

Signed-off-by: Bradley Bolen <bradleybolen@gmail.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index c880489..f6912de 100644 (file)
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -297,7 +297,7 @@ static void mmc_manage_enhanced_area(struct mmc_card *card, u8 *ext_csd)
        }
 }
 
-static void mmc_part_add(struct mmc_card *card, unsigned int size,
+static void mmc_part_add(struct mmc_card *card, u64 size,
                         unsigned int part_cfg, char *name, int idx, bool ro,
                         int area_type)
 {
@@ -313,7 +313,7 @@ static void mmc_manage_gp_partitions(struct mmc_card *card, u8 *ext_csd)
 {
        int idx;
        u8 hc_erase_grp_sz, hc_wp_grp_sz;
-       unsigned int part_size;
+       u64 part_size;
 
        /*
         * General purpose partition feature support --
@@ -343,8 +343,7 @@ static void mmc_manage_gp_partitions(struct mmc_card *card, u8 *ext_csd)
                                (ext_csd[EXT_CSD_GP_SIZE_MULT + idx * 3 + 1]
                                << 8) +
                                ext_csd[EXT_CSD_GP_SIZE_MULT + idx * 3];
-                       part_size *= (size_t)(hc_erase_grp_sz *
-                               hc_wp_grp_sz);
+                       part_size *= (hc_erase_grp_sz * hc_wp_grp_sz);
                        mmc_part_add(card, part_size << 19,
                                EXT_CSD_PART_CONFIG_ACC_GP0 + idx,
                                "gp%d", idx, false,
@@ -362,7 +361,7 @@ static void mmc_manage_gp_partitions(struct mmc_card *card, u8 *ext_csd)
 static int mmc_decode_ext_csd(struct mmc_card *card, u8 *ext_csd)
 {
        int err = 0, idx;
-       unsigned int part_size;
+       u64 part_size;
        struct device_node *np;
        bool broken_hpi = false;
 

diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h
index e459b38..cf3780a 100644 (file)
--- a/include/linux/mmc/card.h
+++ b/include/linux/mmc/card.h
@@ -226,7 +226,7 @@ struct mmc_queue_req;
  * MMC Physical partitions
  */
 struct mmc_part {
-       unsigned int    size;   /* partition size (in bytes) */
+       u64             size;   /* partition size (in bytes) */
        unsigned int    part_cfg;       /* partition type */
        char    name[MAX_MMC_PART_NAME_LEN];
        bool    force_ro;       /* to make boot parts RO by default */