mmc: add erase, secure erase, trim and secure trim operations

SD/MMC cards tend to support an erase operation.  In addition, eMMC v4.4
cards can support secure erase, trim and secure trim operations that are
all variants of the basic erase command.

SD/MMC device attributes "erase_size" and "preferred_erase_size" have been
added.

"erase_size" is the minimum size, in bytes, of an erase operation.  For
MMC, "erase_size" is the erase group size reported by the card.  Note that
"erase_size" does not apply to trim or secure trim operations where the
minimum size is always one 512 byte sector.  For SD, "erase_size" is 512
if the card is block-addressed, 0 otherwise.

SD/MMC cards can erase an arbitrarily large area up to and
including the whole card.  When erasing a large area it may
be desirable to do it in smaller chunks for three reasons:

    1. A single erase command will make all other I/O on the card
       wait.  This is not a problem if the whole card is being erased, but
       erasing one partition will make I/O for another partition on the
       same card wait for the duration of the erase - which could be a
       several minutes.

    2. To be able to inform the user of erase progress.

    3. The erase timeout becomes too large to be very useful.
       Because the erase timeout contains a margin which is multiplied by
       the size of the erase area, the value can end up being several
       minutes for large areas.

"erase_size" is not the most efficient unit to erase (especially for SD
where it is just one sector), hence "preferred_erase_size" provides a good
chunk size for erasing large areas.

For MMC, "preferred_erase_size" is the high-capacity erase size if a card
specifies one, otherwise it is based on the capacity of the card.

For SD, "preferred_erase_size" is the allocation unit size specified by
the card.

"preferred_erase_size" is in bytes.

Signed-off-by: Adrian Hunter <adrian.hunter@nokia.com>
Acked-by: Jens Axboe <axboe@kernel.dk>
Cc: Kyungmin Park <kmpark@infradead.org>
Cc: Madhusudhan Chikkature <madhu.cr@ti.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Ben Gardiner <bengardiner@nanometrics.ca>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

5 files changed, 64 insertions, 7 deletions

diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h
index 4d893eaf8174..6b7525099e56 100644
--- a/include/linux/mmc/card.h
+++ b/include/linux/mmc/card.h
@@ -31,6 +31,7 @@ struct mmc_csd {
         unsigned int            tacc_ns;
         unsigned int            r2w_factor;
         unsigned int            max_dtr;
+        unsigned int            erase_size;             /* In sectors */
         unsigned int            read_blkbits;
         unsigned int            write_blkbits;
         unsigned int            capacity;
@@ -42,9 +43,16 @@ struct mmc_csd {
 
 struct mmc_ext_csd {
         u8                      rev;
+        u8                      erase_group_def;
+        u8                      sec_feature_support;
         unsigned int            sa_timeout;             /* Units: 100ns */
         unsigned int            hs_max_dtr;
         unsigned int            sectors;
+        unsigned int            hc_erase_size;          /* In sectors */
+        unsigned int            hc_erase_timeout;       /* In milliseconds */
+        unsigned int            sec_trim_mult;  /* Secure trim multiplier  */
+        unsigned int            sec_erase_mult; /* Secure erase multiplier */
+        unsigned int            trim_timeout;           /* In milliseconds */
 };
 
 struct sd_scr {
@@ -54,6 +62,12 @@ struct sd_scr {
 #define SD_SCR_BUS_WIDTH_4      (1<<2)
 };
 
+struct sd_ssr {
+        unsigned int            au;                     /* In sectors */
+        unsigned int            erase_timeout;          /* In milliseconds */
+        unsigned int            erase_offset;           /* In milliseconds */
+};
+
 struct sd_switch_caps {
         unsigned int            hs_max_dtr;
 };
@@ -106,6 +120,11 @@ struct mmc_card {
 #define MMC_QUIRK_NONSTD_SDIO   (1<<2)          /* non-standard SDIO card attached */
                                                 /* (missing CIA registers) */
 
+        unsigned int            erase_size;     /* erase size in sectors */
+        unsigned int            erase_shift;    /* if erase unit is power 2 */
+        unsigned int            pref_erase;     /* in sectors */
+        u8                      erased_byte;    /* value of erased bytes */
+
         u32                     raw_cid[4];     /* raw card CID */
         u32                     raw_csd[4];     /* raw card CSD */
         u32                     raw_scr[2];     /* raw card SCR */
@@ -113,6 +132,7 @@ struct mmc_card {
         struct mmc_csd          csd;            /* card specific */
         struct mmc_ext_csd      ext_csd;        /* mmc v4 extended card specific */
         struct sd_scr           scr;            /* extra SD information */
+        struct sd_ssr           ssr;            /* yet more SD information */
         struct sd_switch_caps   sw_caps;        /* switch (CMD6) caps */
 
         unsigned int            sdio_funcs;     /* number of SDIO functions */
diff --git a/include/linux/mmc/core.h b/include/linux/mmc/core.h
index e4898e9eeb59..7429033acb66 100644
--- a/include/linux/mmc/core.h
+++ b/include/linux/mmc/core.h
@@ -92,6 +92,8 @@ struct mmc_command {
  *              actively failing requests
  */
 
+        unsigned int            erase_timeout;  /* in milliseconds */
+
         struct mmc_data         *data;          /* data segment associated with cmd */
         struct mmc_request      *mrq;           /* associated request */
 };
@@ -134,6 +136,23 @@ extern int mmc_wait_for_cmd(struct mmc_host *, struct mmc_command *, int);
 extern int mmc_wait_for_app_cmd(struct mmc_host *, struct mmc_card *,
         struct mmc_command *, int);
 
+#define MMC_ERASE_ARG           0x00000000
+#define MMC_SECURE_ERASE_ARG    0x80000000
+#define MMC_TRIM_ARG            0x00000001
+#define MMC_SECURE_TRIM1_ARG    0x80000001
+#define MMC_SECURE_TRIM2_ARG    0x80008000
+
+#define MMC_SECURE_ARGS         0x80000000
+#define MMC_TRIM_ARGS           0x00008001
+
+extern int mmc_erase(struct mmc_card *card, unsigned int from, unsigned int nr,
+                     unsigned int arg);
+extern int mmc_can_erase(struct mmc_card *card);
+extern int mmc_can_trim(struct mmc_card *card);
+extern int mmc_can_secure_erase_trim(struct mmc_card *card);
+extern int mmc_erase_group_aligned(struct mmc_card *card, unsigned int from,
+                                   unsigned int nr);
+
 extern void mmc_set_data_timeout(struct mmc_data *, const struct mmc_card *);
 extern unsigned int mmc_align_data_size(struct mmc_card *, unsigned int);
 
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index 513ff0376b09..1575b52c3bfa 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -156,6 +156,7 @@ struct mmc_host {
 #define MMC_CAP_DISABLE         (1 << 7)        /* Can the host be disabled */
 #define MMC_CAP_NONREMOVABLE    (1 << 8)        /* Nonremovable e.g. eMMC */
 #define MMC_CAP_WAIT_WHILE_BUSY (1 << 9)        /* Waits while card is busy */
+#define MMC_CAP_ERASE           (1 << 10)       /* Allow erase/trim commands */
 
         mmc_pm_flag_t           pm_caps;        /* supported pm features */
 
diff --git a/include/linux/mmc/mmc.h b/include/linux/mmc/mmc.h
index 52ce98866287..dd11ae51fb68 100644
--- a/include/linux/mmc/mmc.h
+++ b/include/linux/mmc/mmc.h
@@ -251,13 +251,21 @@ struct _mmc_csd {
  * EXT_CSD fields
  */
 
-#define EXT_CSD_BUS_WIDTH       183     /* R/W */
-#define EXT_CSD_HS_TIMING       185     /* R/W */
-#define EXT_CSD_CARD_TYPE       196     /* RO */
-#define EXT_CSD_STRUCTURE       194     /* RO */
-#define EXT_CSD_REV             192     /* RO */
-#define EXT_CSD_SEC_CNT         212     /* RO, 4 bytes */
-#define EXT_CSD_S_A_TIMEOUT     217
+#define EXT_CSD_ERASE_GROUP_DEF         175     /* R/W */
+#define EXT_CSD_ERASED_MEM_CONT         181     /* RO */
+#define EXT_CSD_BUS_WIDTH               183     /* R/W */
+#define EXT_CSD_HS_TIMING               185     /* R/W */
+#define EXT_CSD_REV                     192     /* RO */
+#define EXT_CSD_STRUCTURE               194     /* RO */
+#define EXT_CSD_CARD_TYPE               196     /* RO */
+#define EXT_CSD_SEC_CNT                 212     /* RO, 4 bytes */
+#define EXT_CSD_S_A_TIMEOUT             217     /* RO */
+#define EXT_CSD_ERASE_TIMEOUT_MULT      223     /* RO */
+#define EXT_CSD_HC_ERASE_GRP_SIZE       224     /* RO */
+#define EXT_CSD_SEC_TRIM_MULT           229     /* RO */
+#define EXT_CSD_SEC_ERASE_MULT          230     /* RO */
+#define EXT_CSD_SEC_FEATURE_SUPPORT     231     /* RO */
+#define EXT_CSD_TRIM_MULT               232     /* RO */
 
 /*
  * EXT_CSD field definitions
@@ -275,6 +283,10 @@ struct _mmc_csd {
 #define EXT_CSD_BUS_WIDTH_4     1       /* Card is in 4 bit mode */
 #define EXT_CSD_BUS_WIDTH_8     2       /* Card is in 8 bit mode */
 
+#define EXT_CSD_SEC_ER_EN       BIT(0)
+#define EXT_CSD_SEC_BD_BLK_EN   BIT(2)
+#define EXT_CSD_SEC_GB_CL_EN    BIT(4)
+
 /*
  * MMC_SWITCH access modes
  */
diff --git a/include/linux/mmc/sd.h b/include/linux/mmc/sd.h
index f310062cffb4..3fd85e088cc3 100644
--- a/include/linux/mmc/sd.h
+++ b/include/linux/mmc/sd.h
@@ -21,8 +21,13 @@
   /* class 10 */
 #define SD_SWITCH                 6   /* adtc [31:0] See below   R1  */
 
+  /* class 5 */
+#define SD_ERASE_WR_BLK_START    32   /* ac   [31:0] data addr   R1  */
+#define SD_ERASE_WR_BLK_END      33   /* ac   [31:0] data addr   R1  */
+
   /* Application commands */
 #define SD_APP_SET_BUS_WIDTH      6   /* ac   [1:0] bus width    R1  */
+#define SD_APP_SD_STATUS         13   /* adtc                    R1  */
 #define SD_APP_SEND_NUM_WR_BLKS  22   /* adtc                    R1  */
 #define SD_APP_OP_COND           41   /* bcr  [31:0] OCR         R3  */
 #define SD_APP_SEND_SCR          51   /* adtc                    R1  */