1 files changed, 178 insertions, 159 deletions

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index c773ee545ebd..1d79b8d4ca6d 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1,6 +1,7 @@
 #ifndef _LINUX_BLKDEV_H
 #define _LINUX_BLKDEV_H
 
+#include <linux/sched.h>
 #include <linux/major.h>
 #include <linux/genhd.h>
 #include <linux/list.h>
@@ -16,6 +17,22 @@
 
 #include <asm/scatterlist.h>
 
+#ifdef CONFIG_LBD
+# include <asm/div64.h>
+# define sector_div(a, b) do_div(a, b)
+#else
+# define sector_div(n, b)( \
+{ \
+        int _res; \
+        _res = (n) % (b); \
+        (n) /= (b); \
+        _res; \
+} \
+)
+#endif
+
+#ifdef CONFIG_BLOCK
+
 struct scsi_ioctl_command;
 
 struct request_queue;
@@ -90,7 +107,7 @@ struct io_context {
         atomic_t refcount;
         struct task_struct *task;
 
-        int (*set_ioprio)(struct io_context *, unsigned int);
+        unsigned int ioprio_changed;
 
         /*
          * For request batching
@@ -104,8 +121,7 @@ struct io_context {
 
 void put_io_context(struct io_context *ioc);
 void exit_io_context(void);
-struct io_context *current_io_context(gfp_t gfp_flags);
-struct io_context *get_io_context(gfp_t gfp_flags);
+struct io_context *get_io_context(gfp_t gfp_flags, int node);
 void copy_io_context(struct io_context **pdst, struct io_context **psrc);
 void swap_io_context(struct io_context **ioc1, struct io_context **ioc2);
 
@@ -120,6 +136,90 @@ struct request_list {
         wait_queue_head_t wait[2];
 };
 
+/*
+ * request command types
+ */
+enum rq_cmd_type_bits {
+        REQ_TYPE_FS             = 1,    /* fs request */
+        REQ_TYPE_BLOCK_PC,              /* scsi command */
+        REQ_TYPE_SENSE,                 /* sense request */
+        REQ_TYPE_PM_SUSPEND,            /* suspend request */
+        REQ_TYPE_PM_RESUME,             /* resume request */
+        REQ_TYPE_PM_SHUTDOWN,           /* shutdown request */
+        REQ_TYPE_FLUSH,                 /* flush request */
+        REQ_TYPE_SPECIAL,               /* driver defined type */
+        REQ_TYPE_LINUX_BLOCK,           /* generic block layer message */
+        /*
+         * for ATA/ATAPI devices. this really doesn't belong here, ide should
+         * use REQ_TYPE_SPECIAL and use rq->cmd[0] with the range of driver
+         * private REQ_LB opcodes to differentiate what type of request this is
+         */
+        REQ_TYPE_ATA_CMD,
+        REQ_TYPE_ATA_TASK,
+        REQ_TYPE_ATA_TASKFILE,
+};
+
+/*
+ * For request of type REQ_TYPE_LINUX_BLOCK, rq->cmd[0] is the opcode being
+ * sent down (similar to how REQ_TYPE_BLOCK_PC means that ->cmd[] holds a
+ * SCSI cdb.
+ *
+ * 0x00 -> 0x3f are driver private, to be used for whatever purpose they need,
+ * typically to differentiate REQ_TYPE_SPECIAL requests.
+ *
+ */
+enum {
+        /*
+         * just examples for now
+         */
+        REQ_LB_OP_EJECT = 0x40,         /* eject request */
+        REQ_LB_OP_FLUSH = 0x41,         /* flush device */
+};
+
+/*
+ * request type modified bits. first three 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_SORTED,           /* elevator knows about this request */
+        __REQ_SOFTBARRIER,      /* may not be passed by ioscheduler */
+        __REQ_HARDBARRIER,      /* may not be passed by drive either */
+        __REQ_FUA,              /* forced unit access */
+        __REQ_NOMERGE,          /* don't touch this for merging */
+        __REQ_STARTED,          /* drive already may have started this one */
+        __REQ_DONTPREP,         /* don't call prep for this one */
+        __REQ_QUEUED,           /* uses queueing */
+        __REQ_ELVPRIV,          /* elevator private data attached */
+        __REQ_FAILED,           /* set if the request failed */
+        __REQ_QUIET,            /* don't worry about errors */
+        __REQ_PREEMPT,          /* set for "ide_preempt" requests */
+        __REQ_ORDERED_COLOR,    /* is before or after barrier */
+        __REQ_RW_SYNC,          /* request is sync (O_DIRECT) */
+        __REQ_ALLOCED,          /* request came from our alloc pool */
+        __REQ_RW_META,          /* metadata io request */
+        __REQ_NR_BITS,          /* stops here */
+};
+
+#define REQ_RW          (1 << __REQ_RW)
+#define REQ_FAILFAST    (1 << __REQ_FAILFAST)
+#define REQ_SORTED      (1 << __REQ_SORTED)
+#define REQ_SOFTBARRIER (1 << __REQ_SOFTBARRIER)
+#define REQ_HARDBARRIER (1 << __REQ_HARDBARRIER)
+#define REQ_FUA         (1 << __REQ_FUA)
+#define REQ_NOMERGE     (1 << __REQ_NOMERGE)
+#define REQ_STARTED     (1 << __REQ_STARTED)
+#define REQ_DONTPREP    (1 << __REQ_DONTPREP)
+#define REQ_QUEUED      (1 << __REQ_QUEUED)
+#define REQ_ELVPRIV     (1 << __REQ_ELVPRIV)
+#define REQ_FAILED      (1 << __REQ_FAILED)
+#define REQ_QUIET       (1 << __REQ_QUIET)
+#define REQ_PREEMPT     (1 << __REQ_PREEMPT)
+#define REQ_ORDERED_COLOR       (1 << __REQ_ORDERED_COLOR)
+#define REQ_RW_SYNC     (1 << __REQ_RW_SYNC)
+#define REQ_ALLOCED     (1 << __REQ_ALLOCED)
+#define REQ_RW_META     (1 << __REQ_RW_META)
+
 #define BLK_MAX_CDB     16
 
 /*
@@ -129,30 +229,46 @@ struct request {
         struct list_head queuelist;
         struct list_head donelist;
 
-        unsigned long flags;            /* see REQ_ bits below */
+        request_queue_t *q;
+
+        unsigned int cmd_flags;
+        enum rq_cmd_type_bits cmd_type;
 
         /* Maintain bio traversal state for part by part I/O submission.
          * hard_* are block layer internals, no driver should touch them!
          */
 
         sector_t sector;                /* next sector to submit */
+        sector_t hard_sector;           /* next sector to complete */
         unsigned long nr_sectors;       /* no. of sectors left to submit */
+        unsigned long hard_nr_sectors;  /* no. of sectors left to complete */
         /* no. of sectors left to submit in the current segment */
         unsigned int current_nr_sectors;
 
-        sector_t hard_sector;           /* next sector to complete */
-        unsigned long hard_nr_sectors;  /* no. of sectors left to complete */
         /* no. of sectors left to complete in the current segment */
         unsigned int hard_cur_sectors;
 
         struct bio *bio;
         struct bio *biotail;
 
+        struct hlist_node hash; /* merge hash */
+        /*
+         * The rb_node is only used inside the io scheduler, requests
+         * are pruned when moved to the dispatch queue. So let the
+         * completion_data share space with the rb_node.
+         */
+        union {
+                struct rb_node rb_node; /* sort/lookup */
+                void *completion_data;
+        };
+
+        /*
+         * two pointers are available for the IO schedulers, if they need
+         * more they have to dynamically allocate it.
+         */
         void *elevator_private;
-        void *completion_data;
+        void *elevator_private2;
 
-        int rq_status;  /* should split this into a few status bits */
-        int errors;
         struct gendisk *rq_disk;
         unsigned long start_time;
 
@@ -170,15 +286,13 @@ struct request {
 
         unsigned short ioprio;
 
+        void *special;
+        char *buffer;
+
         int tag;
+        int errors;
 
         int ref_count;
-        request_queue_t *q;
-        struct request_list *rl;
-
-        struct completion *waiting;
-        void *special;
-        char *buffer;
 
         /*
          * when request is used as a packet command carrier
@@ -195,80 +309,14 @@ struct request {
         int retries;
 
         /*
-         * completion callback. end_io_data should be folded in with waiting
+         * completion callback.
          */
         rq_end_io_fn *end_io;
         void *end_io_data;
 };
 
 /*
- * first three 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_SORTED,           /* elevator knows about this request */
-        __REQ_SOFTBARRIER,      /* may not be passed by ioscheduler */
-        __REQ_HARDBARRIER,      /* may not be passed by drive either */
-        __REQ_FUA,              /* forced unit access */
-        __REQ_CMD,              /* is a regular fs rw request */
-        __REQ_NOMERGE,          /* don't touch this for merging */
-        __REQ_STARTED,          /* drive already may have started this one */
-        __REQ_DONTPREP,         /* don't call prep for this one */
-        __REQ_QUEUED,           /* uses queueing */
-        __REQ_ELVPRIV,          /* elevator private data attached */
-        /*
-         * for ATA/ATAPI devices
-         */
-        __REQ_PC,               /* packet command (special) */
-        __REQ_BLOCK_PC,         /* queued down pc from block layer */
-        __REQ_SENSE,            /* sense retrival */
-
-        __REQ_FAILED,           /* set if the request failed */
-        __REQ_QUIET,            /* don't worry about errors */
-        __REQ_SPECIAL,          /* driver suplied command */
-        __REQ_DRIVE_CMD,
-        __REQ_DRIVE_TASK,
-        __REQ_DRIVE_TASKFILE,
-        __REQ_PREEMPT,          /* set for "ide_preempt" requests */
-        __REQ_PM_SUSPEND,       /* suspend request */
-        __REQ_PM_RESUME,        /* resume request */
-        __REQ_PM_SHUTDOWN,      /* shutdown request */
-        __REQ_ORDERED_COLOR,    /* is before or after barrier */
-        __REQ_RW_SYNC,          /* request is sync (O_DIRECT) */
-        __REQ_NR_BITS,          /* stops here */
-};
-
-#define REQ_RW          (1 << __REQ_RW)
-#define REQ_FAILFAST    (1 << __REQ_FAILFAST)
-#define REQ_SORTED      (1 << __REQ_SORTED)
-#define REQ_SOFTBARRIER (1 << __REQ_SOFTBARRIER)
-#define REQ_HARDBARRIER (1 << __REQ_HARDBARRIER)
-#define REQ_FUA         (1 << __REQ_FUA)
-#define REQ_CMD         (1 << __REQ_CMD)
-#define REQ_NOMERGE     (1 << __REQ_NOMERGE)
-#define REQ_STARTED     (1 << __REQ_STARTED)
-#define REQ_DONTPREP    (1 << __REQ_DONTPREP)
-#define REQ_QUEUED      (1 << __REQ_QUEUED)
-#define REQ_ELVPRIV     (1 << __REQ_ELVPRIV)
-#define REQ_PC          (1 << __REQ_PC)
-#define REQ_BLOCK_PC    (1 << __REQ_BLOCK_PC)
-#define REQ_SENSE       (1 << __REQ_SENSE)
-#define REQ_FAILED      (1 << __REQ_FAILED)
-#define REQ_QUIET       (1 << __REQ_QUIET)
-#define REQ_SPECIAL     (1 << __REQ_SPECIAL)
-#define REQ_DRIVE_CMD   (1 << __REQ_DRIVE_CMD)
-#define REQ_DRIVE_TASK  (1 << __REQ_DRIVE_TASK)
-#define REQ_DRIVE_TASKFILE      (1 << __REQ_DRIVE_TASKFILE)
-#define REQ_PREEMPT     (1 << __REQ_PREEMPT)
-#define REQ_PM_SUSPEND  (1 << __REQ_PM_SUSPEND)
-#define REQ_PM_RESUME   (1 << __REQ_PM_RESUME)
-#define REQ_PM_SHUTDOWN (1 << __REQ_PM_SHUTDOWN)
-#define REQ_ORDERED_COLOR       (1 << __REQ_ORDERED_COLOR)
-#define REQ_RW_SYNC     (1 << __REQ_RW_SYNC)
-
-/*
- * State information carried for REQ_PM_SUSPEND and REQ_PM_RESUME
+ * State information carried for REQ_TYPE_PM_SUSPEND and REQ_TYPE_PM_RESUME
  * requests. Some step values could eventually be made generic.
  */
 struct request_pm_state
@@ -417,9 +465,9 @@ struct request_queue
         unsigned int            sg_timeout;
         unsigned int            sg_reserved_size;
         int                     node;
-
+#ifdef CONFIG_BLK_DEV_IO_TRACE
         struct blk_trace        *blk_trace;
-
+#endif
         /*
          * reserved for flush operations
          */
@@ -432,9 +480,6 @@ struct request_queue
         struct mutex            sysfs_lock;
 };
 
-#define RQ_INACTIVE             (-1)
-#define RQ_ACTIVE               1
-
 #define QUEUE_FLAG_CLUSTER      0       /* cluster several segments into 1 */
 #define QUEUE_FLAG_QUEUED       1       /* uses generic tag queueing */
 #define QUEUE_FLAG_STOPPED      2       /* queue is stopped */
@@ -490,25 +535,34 @@ enum {
 #define blk_queue_stopped(q)    test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)
 #define blk_queue_flushing(q)   ((q)->ordseq)
 
-#define blk_fs_request(rq)      ((rq)->flags & REQ_CMD)
-#define blk_pc_request(rq)      ((rq)->flags & REQ_BLOCK_PC)
-#define blk_noretry_request(rq) ((rq)->flags & REQ_FAILFAST)
-#define blk_rq_started(rq)      ((rq)->flags & REQ_STARTED)
+#define blk_fs_request(rq)      ((rq)->cmd_type == REQ_TYPE_FS)
+#define blk_pc_request(rq)      ((rq)->cmd_type == REQ_TYPE_BLOCK_PC)
+#define blk_special_request(rq) ((rq)->cmd_type == REQ_TYPE_SPECIAL)
+#define blk_sense_request(rq)   ((rq)->cmd_type == REQ_TYPE_SENSE)
+
+#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_pm_suspend_request(rq)      ((rq)->flags & REQ_PM_SUSPEND)
-#define blk_pm_resume_request(rq)       ((rq)->flags & REQ_PM_RESUME)
+#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)
 #define blk_pm_request(rq)      \
-        ((rq)->flags & (REQ_PM_SUSPEND | REQ_PM_RESUME))
+        (blk_pm_suspend_request(rq) || blk_pm_resume_request(rq))
 
-#define blk_sorted_rq(rq)       ((rq)->flags & REQ_SORTED)
-#define blk_barrier_rq(rq)      ((rq)->flags & REQ_HARDBARRIER)
-#define blk_fua_rq(rq)          ((rq)->flags & REQ_FUA)
+#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 list_entry_rq(ptr)      list_entry((ptr), struct request, queuelist)
 
-#define rq_data_dir(rq)         ((rq)->flags & 1)
+#define rq_data_dir(rq)         ((rq)->cmd_flags & 1)
+
+/*
+ * We regard a request as sync, if it's a READ or a SYNC write.
+ */
+#define rq_is_sync(rq)          (rq_data_dir((rq)) == READ || (rq)->cmd_flags & REQ_RW_SYNC)
+#define rq_is_meta(rq)          ((rq)->cmd_flags & REQ_RW_META)
 
 static inline int blk_queue_full(struct request_queue *q, int rw)
 {
@@ -541,13 +595,7 @@ 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)->flags & RQ_NOMERGE_FLAGS) && blk_fs_request((rq)))
-
-/*
- * noop, requests are automagically marked as active/inactive by I/O
- * scheduler -- see elv_next_request
- */
-#define blk_queue_headactive(q, head_active)
+        (!((rq)->cmd_flags & RQ_NOMERGE_FLAGS) && blk_fs_request((rq)))
 
 /*
  * q->prep_rq_fn return values
@@ -586,11 +634,6 @@ static inline void blk_queue_bounce(request_queue_t *q, struct bio **bio)
         if ((rq->bio))                  \
                 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)
 
-struct sec_size {
-        unsigned block_size;
-        unsigned block_size_bits;
-};
-
 extern int blk_register_queue(struct gendisk *disk);
 extern void blk_unregister_queue(struct gendisk *disk);
 extern void register_disk(struct gendisk *dev);
@@ -612,6 +655,7 @@ extern void blk_stop_queue(request_queue_t *q);
 extern void blk_sync_queue(struct request_queue *q);
 extern void __blk_stop_queue(request_queue_t *q);
 extern void blk_run_queue(request_queue_t *);
+extern void blk_start_queueing(request_queue_t *);
 extern void blk_queue_activity_fn(request_queue_t *, activity_fn *, void *);
 extern int blk_rq_map_user(request_queue_t *, struct request *, void __user *, unsigned int);
 extern int blk_rq_unmap_user(struct bio *, unsigned int);
@@ -655,16 +699,6 @@ extern void end_that_request_last(struct request *, int);
 extern void end_request(struct request *req, int uptodate);
 extern void blk_complete_request(struct request *);
 
-static inline int rq_all_done(struct request *rq, unsigned int nr_bytes)
-{
-        if (blk_fs_request(rq))
-                return (nr_bytes >= (rq->hard_nr_sectors << 9));
-        else if (blk_pc_request(rq))
-                return nr_bytes >= rq->data_len;
-
-        return 0;
-}
-
 /*
  * end_that_request_first/chunk() takes an uptodate argument. we account
  * any value <= as an io error. 0 means -EIO for compatability reasons,
@@ -679,21 +713,6 @@ static inline void blkdev_dequeue_request(struct request *req)
 }
 
 /*
- * This should be in elevator.h, but that requires pulling in rq and q
- */
-static inline void elv_dispatch_add_tail(struct request_queue *q,
-                                         struct request *rq)
-{
-        if (q->last_merge == rq)
-                q->last_merge = NULL;
-        q->nr_sorted--;
-
-        q->end_sector = rq_end_sector(rq);
-        q->boundary_rq = rq;
-        list_add_tail(&rq->queuelist, &q->queue_head);
-}
-
-/*
  * Access functions for manipulating queue properties
  */
 extern request_queue_t *blk_init_queue_node(request_fn_proc *rfn,
@@ -737,7 +756,7 @@ extern void blk_put_queue(request_queue_t *);
  */
 #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)->flags & REQ_QUEUED)
+#define blk_rq_tagged(rq)               ((rq)->cmd_flags & REQ_QUEUED)
 extern int blk_queue_start_tag(request_queue_t *, struct request *);
 extern struct request *blk_queue_find_tag(request_queue_t *, int);
 extern void blk_queue_end_tag(request_queue_t *, struct request *);
@@ -787,14 +806,6 @@ static inline int queue_dma_alignment(request_queue_t *q)
         return retval;
 }
 
-static inline int bdev_dma_aligment(struct block_device *bdev)
-{
-        return queue_dma_alignment(bdev_get_queue(bdev));
-}
-
-#define blk_finished_io(nsects) do { } while (0)
-#define blk_started_io(nsects)  do { } while (0)
-
 /* assumes size > 256 */
 static inline unsigned int blksize_bits(unsigned int size)
 {
@@ -824,24 +835,32 @@ struct work_struct;
 int kblockd_schedule_work(struct work_struct *work);
 void kblockd_flush(void);
 
-#ifdef CONFIG_LBD
-# include <asm/div64.h>
-# define sector_div(a, b) do_div(a, b)
-#else
-# define sector_div(n, b)( \
-{ \
-        int _res; \
-        _res = (n) % (b); \
-        (n) /= (b); \
-        _res; \
-} \
-)
-#endif 
-
 #define MODULE_ALIAS_BLOCKDEV(major,minor) \
         MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor))
 #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \
         MODULE_ALIAS("block-major-" __stringify(major) "-*")
 
 
+#else /* CONFIG_BLOCK */
+/*
+ * stubs for when the block layer is configured out
+ */
+#define buffer_heads_over_limit 0
+
+static inline long blk_congestion_wait(int rw, long timeout)
+{
+        return io_schedule_timeout(timeout);
+}
+
+static inline long nr_blockdev_pages(void)
+{
+        return 0;
+}
+
+static inline void exit_io_context(void)
+{
+}
+
+#endif /* CONFIG_BLOCK */
+
 #endif