ata: Add TRIM infrastructure

This is common code shared between the IDE and libata implementations

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

1 files changed, 41 insertions, 0 deletions

diff --git a/include/linux/ata.h b/include/linux/ata.h
index 6617c9f8f2ca..cb79b7a208e1 100644
--- a/include/linux/ata.h
+++ b/include/linux/ata.h
@@ -29,6 +29,8 @@
 #ifndef __LINUX_ATA_H__
 #define __LINUX_ATA_H__
 
+#include <linux/kernel.h>
+#include <linux/string.h>
 #include <linux/types.h>
 #include <asm/byteorder.h>
 
@@ -91,6 +93,7 @@ enum {
         ATA_ID_CFA_POWER        = 160,
         ATA_ID_CFA_KEY_MGMT     = 162,
         ATA_ID_CFA_MODES        = 163,
+        ATA_ID_DATA_SET_MGMT    = 169,
         ATA_ID_ROT_SPEED        = 217,
         ATA_ID_PIO4             = (1 << 1),
 
@@ -248,6 +251,7 @@ enum {
         ATA_CMD_SMART           = 0xB0,
         ATA_CMD_MEDIA_LOCK      = 0xDE,
         ATA_CMD_MEDIA_UNLOCK    = 0xDF,
+        ATA_CMD_DSM             = 0x06,
         /* marked obsolete in the ATA/ATAPI-7 spec */
         ATA_CMD_RESTORE         = 0x10,
 
@@ -321,6 +325,9 @@ enum {
         ATA_SMART_READ_VALUES   = 0xD0,
         ATA_SMART_READ_THRESHOLDS = 0xD1,
 
+        /* feature values for Data Set Management */
+        ATA_DSM_TRIM            = 0x01,
+
         /* password used in LBA Mid / LBA High for executing SMART commands */
         ATA_SMART_LBAM_PASS     = 0x4F,
         ATA_SMART_LBAH_PASS     = 0xC2,
@@ -723,6 +730,14 @@ static inline int ata_id_has_unload(const u16 *id)
         return 0;
 }
 
+static inline int ata_id_has_trim(const u16 *id)
+{
+        if (ata_id_major_version(id) >= 7 &&
+            (id[ATA_ID_DATA_SET_MGMT] & 1))
+                return 1;
+        return 0;
+}
+
 static inline int ata_id_current_chs_valid(const u16 *id)
 {
         /* For ATA-1 devices, if the INITIALIZE DEVICE PARAMETERS command
@@ -863,6 +878,32 @@ static inline void ata_id_to_hd_driveid(u16 *id)
 #endif
 }
 
+/*
+ * Write up to 'max' LBA Range Entries to the buffer that will cover the
+ * extent from sector to sector + count.  This is used for TRIM and for
+ * ADD LBA(S) TO NV CACHE PINNED SET.
+ */
+static inline unsigned ata_set_lba_range_entries(void *_buffer, unsigned max,
+                                                u64 sector, unsigned long count)
+{
+        __le64 *buffer = _buffer;
+        unsigned i = 0;
+
+        while (i < max) {
+                u64 entry = sector |
+                        ((u64)(count > 0xffff ? 0xffff : count) << 48);
+                buffer[i++] = __cpu_to_le64(entry);
+                if (count <= 0xffff)
+                        break;
+                count -= 0xffff;
+                sector += 0xffff;
+        }
+
+        max = ALIGN(i * 8, 512);
+        memset(buffer + i, 0, max - i * 8);
+        return max;
+}
+
 static inline int is_multi_taskfile(struct ata_taskfile *tf)
 {
         return (tf->command == ATA_CMD_READ_MULTI) ||