Allow elevators to sort/merge discard requests

[pandora-kernel.git] / include / linux / blkdev.h

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index e61f22b..e9eb35c 100644 (file)
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -81,14 +81,16 @@ enum {
         */
        REQ_LB_OP_EJECT = 0x40,         /* eject request */
        REQ_LB_OP_FLUSH = 0x41,         /* flush device */
+       REQ_LB_OP_DISCARD = 0x42,       /* discard sectors */
 };
 
 /*
- * request type modified bits. first three bits match BIO_RW* bits, important
+ * request type modified bits. first two bits match BIO_RW* bits, important
  */
 enum rq_flag_bits {
        __REQ_RW,               /* not set, read. set, write */
        __REQ_FAILFAST,         /* no low level driver retries */
+       __REQ_DISCARD,          /* request to discard sectors */
        __REQ_SORTED,           /* elevator knows about this request */
        __REQ_SOFTBARRIER,      /* may not be passed by ioscheduler */
        __REQ_HARDBARRIER,      /* may not be passed by drive either */
@@ -111,6 +113,7 @@ enum rq_flag_bits {
 };
 
 #define REQ_RW         (1 << __REQ_RW)
+#define REQ_DISCARD    (1 << __REQ_DISCARD)
 #define REQ_FAILFAST   (1 << __REQ_FAILFAST)
 #define REQ_SORTED     (1 << __REQ_SORTED)
 #define REQ_SOFTBARRIER        (1 << __REQ_SOFTBARRIER)
@@ -252,6 +255,7 @@ typedef void (request_fn_proc) (struct request_queue *q);
 typedef int (make_request_fn) (struct request_queue *q, struct bio *bio);
 typedef int (prep_rq_fn) (struct request_queue *, struct request *);
 typedef void (unplug_fn) (struct request_queue *);
+typedef int (prepare_discard_fn) (struct request_queue *, struct request *);
 
 struct bio_vec;
 struct bvec_merge_data {
@@ -280,6 +284,15 @@ struct blk_queue_tag {
        atomic_t refcnt;                /* map can be shared */
 };
 
+#define BLK_SCSI_MAX_CMDS      (256)
+#define BLK_SCSI_CMD_PER_LONG  (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
+
+struct blk_cmd_filter {
+       unsigned long read_ok[BLK_SCSI_CMD_PER_LONG];
+       unsigned long write_ok[BLK_SCSI_CMD_PER_LONG];
+       struct kobject kobj;
+};
+
 struct request_queue
 {
        /*
@@ -298,6 +311,7 @@ struct request_queue
        make_request_fn         *make_request_fn;
        prep_rq_fn              *prep_rq_fn;
        unplug_fn               *unplug_fn;
+       prepare_discard_fn      *prepare_discard_fn;
        merge_bvec_fn           *merge_bvec_fn;
        prepare_flush_fn        *prepare_flush_fn;
        softirq_done_fn         *softirq_done_fn;
@@ -398,6 +412,7 @@ struct request_queue
 #if defined(CONFIG_BLK_DEV_BSG)
        struct bsg_class_device bsg_dev;
 #endif
+       struct blk_cmd_filter cmd_filter;
 };
 
 #define QUEUE_FLAG_CLUSTER     0       /* cluster several segments into 1 */
@@ -526,7 +541,7 @@ enum {
 #define blk_noretry_request(rq)        ((rq)->cmd_flags & REQ_FAILFAST)
 #define blk_rq_started(rq)     ((rq)->cmd_flags & REQ_STARTED)
 
-#define blk_account_rq(rq)     (blk_rq_started(rq) && blk_fs_request(rq))
+#define blk_account_rq(rq)     (blk_rq_started(rq) && (blk_fs_request(rq) || blk_discard_rq(rq))) 
 
 #define blk_pm_suspend_request(rq)     ((rq)->cmd_type == REQ_TYPE_PM_SUSPEND)
 #define blk_pm_resume_request(rq)      ((rq)->cmd_type == REQ_TYPE_PM_RESUME)
@@ -536,6 +551,7 @@ enum {
 #define blk_sorted_rq(rq)      ((rq)->cmd_flags & REQ_SORTED)
 #define blk_barrier_rq(rq)     ((rq)->cmd_flags & REQ_HARDBARRIER)
 #define blk_fua_rq(rq)         ((rq)->cmd_flags & REQ_FUA)
+#define blk_discard_rq(rq)     ((rq)->cmd_flags & REQ_DISCARD)
 #define blk_bidi_rq(rq)                ((rq)->next_rq != NULL)
 #define blk_empty_barrier(rq)  (blk_barrier_rq(rq) && blk_fs_request(rq) && !(rq)->hard_nr_sectors)
 /* rq->queuelist of dequeued request must be list_empty() */
@@ -582,7 +598,8 @@ static inline void blk_clear_queue_full(struct request_queue *q, int rw)
 #define RQ_NOMERGE_FLAGS       \
        (REQ_NOMERGE | REQ_STARTED | REQ_HARDBARRIER | REQ_SOFTBARRIER)
 #define rq_mergeable(rq)       \
-       (!((rq)->cmd_flags & RQ_NOMERGE_FLAGS) && blk_fs_request((rq)))
+       (!((rq)->cmd_flags & RQ_NOMERGE_FLAGS) && \
+        (blk_discard_rq(rq) || blk_fs_request((rq))))
 
 /*
  * q->prep_rq_fn return values
@@ -786,6 +803,7 @@ extern void blk_queue_merge_bvec(struct request_queue *, merge_bvec_fn *);
 extern void blk_queue_dma_alignment(struct request_queue *, int);
 extern void blk_queue_update_dma_alignment(struct request_queue *, int);
 extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *);
+extern void blk_queue_set_discard(struct request_queue *, prepare_discard_fn *);
 extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev);
 extern int blk_queue_ordered(struct request_queue *, unsigned, prepare_flush_fn *);
 extern int blk_do_ordered(struct request_queue *, struct request **);
@@ -807,8 +825,6 @@ extern void blk_put_queue(struct request_queue *);
 /*
  * tag stuff
  */
-#define blk_queue_tag_depth(q)         ((q)->queue_tags->busy)
-#define blk_queue_tag_queue(q)         ((q)->queue_tags->busy < (q)->queue_tags->max_depth)
 #define blk_rq_tagged(rq)              ((rq)->cmd_flags & REQ_QUEUED)
 extern int blk_queue_start_tag(struct request_queue *, struct request *);
 extern struct request *blk_queue_find_tag(struct request_queue *, int);
@@ -829,15 +845,23 @@ static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt,
 }
 
 extern int blkdev_issue_flush(struct block_device *, sector_t *);
+extern int blkdev_issue_discard(struct block_device *, sector_t sector,
+                               unsigned nr_sects);
+
+static inline int sb_issue_discard(struct super_block *sb,
+                                  sector_t block, unsigned nr_blocks)
+{
+       block <<= (sb->s_blocksize_bits - 9);
+       nr_blocks <<= (sb->s_blocksize_bits - 9);
+       return blkdev_issue_discard(sb->s_bdev, block, nr_blocks);
+}
 
 /*
 * command filter functions
 */
-extern int blk_verify_command(struct file *file, unsigned char *cmd);
-extern int blk_cmd_filter_verify_command(struct blk_scsi_cmd_filter *filter,
-                                        unsigned char *cmd, mode_t *f_mode);
-extern int blk_register_filter(struct gendisk *disk);
-extern void blk_unregister_filter(struct gendisk *disk);
+extern int blk_verify_command(struct blk_cmd_filter *filter,
+                             unsigned char *cmd, int has_write_perm);
+extern void blk_set_cmd_filter_defaults(struct blk_cmd_filter *filter);
 
 #define MAX_PHYS_SEGMENTS 128
 #define MAX_HW_SEGMENTS 128