Merge branch 'for-2.6.36' of git://git.kernel.dk/linux-2.6-block

* 'for-2.6.36' of git://git.kernel.dk/linux-2.6-block: (149 commits)
  block: make sure that REQ_* types are seen even with CONFIG_BLOCK=n
  xen-blkfront: fix missing out label
  blkdev: fix blkdev_issue_zeroout return value
  block: update request stacking methods to support discards
  block: fix missing export of blk_types.h
  writeback: fix bad _bh spinlock nesting
  drbd: revert "delay probes", feature is being re-implemented differently
  drbd: Initialize all members of sync_conf to their defaults [Bugz 315]
  drbd: Disable delay probes for the upcomming release
  writeback: cleanup bdi_register
  writeback: add new tracepoints
  writeback: remove unnecessary init_timer call
  writeback: optimize periodic bdi thread wakeups
  writeback: prevent unnecessary bdi threads wakeups
  writeback: move bdi threads exiting logic to the forker thread
  writeback: restructure bdi forker loop a little
  writeback: move last_active to bdi
  writeback: do not remove bdi from bdi_list
  writeback: simplify bdi code a little
  writeback: do not lose wake-ups in bdi threads
  ...

Fixed up pretty trivial conflicts in drivers/block/virtio_blk.c and
drivers/scsi/scsi_error.c as per Jens.

11 files changed, 292 insertions, 310 deletions

diff --git a/include/linux/Kbuild b/include/linux/Kbuild
index 2547daf2aef2..9d65d4d0bd9c 100644
--- a/include/linux/Kbuild
+++ b/include/linux/Kbuild
@@ -39,6 +39,7 @@ header-y += ax25.h
 header-y += b1lli.h
 header-y += baycom.h
 header-y += bfs_fs.h
+header-y += blk_types.h
 header-y += blkpg.h
 header-y += bpqether.h
 header-y += bsg.h
diff --git a/include/linux/audit.h b/include/linux/audit.h
index f391d45c8aea..e24afabc548f 100644
--- a/include/linux/audit.h
+++ b/include/linux/audit.h
@@ -544,7 +544,7 @@ extern int audit_signals;
 #define audit_putname(n) do { ; } while (0)
 #define __audit_inode(n,d) do { ; } while (0)
 #define __audit_inode_child(i,p) do { ; } while (0)
-#define audit_inode(n,d) do { ; } while (0)
+#define audit_inode(n,d) do { (void)(d); } while (0)
 #define audit_inode_child(i,p) do { ; } while (0)
 #define audit_core_dumps(i) do { ; } while (0)
 #define auditsc_get_stamp(c,t,s) (0)
diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h
index e9aec0d099df..7628219e5386 100644
--- a/include/linux/backing-dev.h
+++ b/include/linux/backing-dev.h
@@ -45,22 +45,21 @@ enum bdi_stat_item {
 #define BDI_STAT_BATCH (8*(1+ilog2(nr_cpu_ids)))
 
 struct bdi_writeback {
-        struct list_head list;                  /* hangs off the bdi */
-
-        struct backing_dev_info *bdi;           /* our parent bdi */
+        struct backing_dev_info *bdi;   /* our parent bdi */
         unsigned int nr;
 
-        unsigned long last_old_flush;           /* last old data flush */
+        unsigned long last_old_flush;   /* last old data flush */
+        unsigned long last_active;      /* last time bdi thread was active */
 
-        struct task_struct      *task;          /* writeback task */
-        struct list_head        b_dirty;        /* dirty inodes */
-        struct list_head        b_io;           /* parked for writeback */
-        struct list_head        b_more_io;      /* parked for more writeback */
+        struct task_struct *task;       /* writeback thread */
+        struct timer_list wakeup_timer; /* used for delayed bdi thread wakeup */
+        struct list_head b_dirty;       /* dirty inodes */
+        struct list_head b_io;          /* parked for writeback */
+        struct list_head b_more_io;     /* parked for more writeback */
 };
 
 struct backing_dev_info {
         struct list_head bdi_list;
-        struct rcu_head rcu_head;
         unsigned long ra_pages; /* max readahead in PAGE_CACHE_SIZE units */
         unsigned long state;    /* Always use atomic bitops on this */
         unsigned int capabilities; /* Device capabilities */
@@ -80,8 +79,7 @@ struct backing_dev_info {
         unsigned int max_ratio, max_prop_frac;
 
         struct bdi_writeback wb;  /* default writeback info for this bdi */
-        spinlock_t wb_lock;       /* protects update side of wb_list */
-        struct list_head wb_list; /* the flusher threads hanging off this bdi */
+        spinlock_t wb_lock;       /* protects work_list */
 
         struct list_head work_list;
 
@@ -105,9 +103,10 @@ void bdi_unregister(struct backing_dev_info *bdi);
 int bdi_setup_and_register(struct backing_dev_info *, char *, unsigned int);
 void bdi_start_writeback(struct backing_dev_info *bdi, long nr_pages);
 void bdi_start_background_writeback(struct backing_dev_info *bdi);
-int bdi_writeback_task(struct bdi_writeback *wb);
+int bdi_writeback_thread(void *data);
 int bdi_has_dirty_io(struct backing_dev_info *bdi);
 void bdi_arm_supers_timer(void);
+void bdi_wakeup_thread_delayed(struct backing_dev_info *bdi);
 
 extern spinlock_t bdi_lock;
 extern struct list_head bdi_list;
diff --git a/include/linux/bio.h b/include/linux/bio.h
index 7fc5606e6ea5..5274103434ad 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -9,7 +9,7 @@
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
-
+ *
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
@@ -28,6 +28,9 @@
 
 #include <asm/io.h>
 
+/* struct bio, bio_vec and BIO_* flags are defined in blk_types.h */
+#include <linux/blk_types.h>
+
 #define BIO_DEBUG
 
 #ifdef BIO_DEBUG
@@ -41,154 +44,6 @@
 #define BIO_MAX_SECTORS         (BIO_MAX_SIZE >> 9)
 
 /*
- * was unsigned short, but we might as well be ready for > 64kB I/O pages
- */
-struct bio_vec {
-        struct page     *bv_page;
-        unsigned int    bv_len;
-        unsigned int    bv_offset;
-};
-
-struct bio_set;
-struct bio;
-struct bio_integrity_payload;
-typedef void (bio_end_io_t) (struct bio *, int);
-typedef void (bio_destructor_t) (struct bio *);
-
-/*
- * main unit of I/O for the block layer and lower layers (ie drivers and
- * stacking drivers)
- */
-struct bio {
-        sector_t                bi_sector;      /* device address in 512 byte
-                                                   sectors */
-        struct bio              *bi_next;       /* request queue link */
-        struct block_device     *bi_bdev;
-        unsigned long           bi_flags;       /* status, command, etc */
-        unsigned long           bi_rw;          /* bottom bits READ/WRITE,
-                                                 * top bits priority
-                                                 */
-
-        unsigned short          bi_vcnt;        /* how many bio_vec's */
-        unsigned short          bi_idx;         /* current index into bvl_vec */
-
-        /* Number of segments in this BIO after
-         * physical address coalescing is performed.
-         */
-        unsigned int            bi_phys_segments;
-
-        unsigned int            bi_size;        /* residual I/O count */
-
-        /*
-         * To keep track of the max segment size, we account for the
-         * sizes of the first and last mergeable segments in this bio.
-         */
-        unsigned int            bi_seg_front_size;
-        unsigned int            bi_seg_back_size;
-
-        unsigned int            bi_max_vecs;    /* max bvl_vecs we can hold */
-
-        unsigned int            bi_comp_cpu;    /* completion CPU */
-
-        atomic_t                bi_cnt;         /* pin count */
-
-        struct bio_vec          *bi_io_vec;     /* the actual vec list */
-
-        bio_end_io_t            *bi_end_io;
-
-        void                    *bi_private;
-#if defined(CONFIG_BLK_DEV_INTEGRITY)
-        struct bio_integrity_payload *bi_integrity;  /* data integrity */
-#endif
-
-        bio_destructor_t        *bi_destructor; /* destructor */
-
-        /*
-         * We can inline a number of vecs at the end of the bio, to avoid
-         * double allocations for a small number of bio_vecs. This member
-         * MUST obviously be kept at the very end of the bio.
-         */
-        struct bio_vec          bi_inline_vecs[0];
-};
-
-/*
- * bio flags
- */
-#define BIO_UPTODATE    0       /* ok after I/O completion */
-#define BIO_RW_BLOCK    1       /* RW_AHEAD set, and read/write would block */
-#define BIO_EOF         2       /* out-out-bounds error */
-#define BIO_SEG_VALID   3       /* bi_phys_segments valid */
-#define BIO_CLONED      4       /* doesn't own data */
-#define BIO_BOUNCED     5       /* bio is a bounce bio */
-#define BIO_USER_MAPPED 6       /* contains user pages */
-#define BIO_EOPNOTSUPP  7       /* not supported */
-#define BIO_CPU_AFFINE  8       /* complete bio on same CPU as submitted */
-#define BIO_NULL_MAPPED 9       /* contains invalid user pages */
-#define BIO_FS_INTEGRITY 10     /* fs owns integrity data, not block layer */
-#define BIO_QUIET       11      /* Make BIO Quiet */
-#define bio_flagged(bio, flag)  ((bio)->bi_flags & (1 << (flag)))
-
-/*
- * top 4 bits of bio flags indicate the pool this bio came from
- */
-#define BIO_POOL_BITS           (4)
-#define BIO_POOL_NONE           ((1UL << BIO_POOL_BITS) - 1)
-#define BIO_POOL_OFFSET         (BITS_PER_LONG - BIO_POOL_BITS)
-#define BIO_POOL_MASK           (1UL << BIO_POOL_OFFSET)
-#define BIO_POOL_IDX(bio)       ((bio)->bi_flags >> BIO_POOL_OFFSET)    
-
-/*
- * bio bi_rw flags
- *
- * bit 0 -- data direction
- *      If not set, bio is a read from device. If set, it's a write to device.
- * bit 1 -- fail fast device errors
- * bit 2 -- fail fast transport errors
- * bit 3 -- fail fast driver errors
- * bit 4 -- rw-ahead when set
- * bit 5 -- barrier
- *      Insert a serialization point in the IO queue, forcing previously
- *      submitted IO to be completed before this one is issued.
- * bit 6 -- synchronous I/O hint.
- * bit 7 -- Unplug the device immediately after submitting this bio.
- * bit 8 -- metadata request
- *      Used for tracing to differentiate metadata and data IO. May also
- *      get some preferential treatment in the IO scheduler
- * bit 9 -- discard sectors
- *      Informs the lower level device that this range of sectors is no longer
- *      used by the file system and may thus be freed by the device. Used
- *      for flash based storage.
- *      Don't want driver retries for any fast fail whatever the reason.
- * bit 10 -- Tell the IO scheduler not to wait for more requests after this
-        one has been submitted, even if it is a SYNC request.
- */
-enum bio_rw_flags {
-        BIO_RW,
-        BIO_RW_FAILFAST_DEV,
-        BIO_RW_FAILFAST_TRANSPORT,
-        BIO_RW_FAILFAST_DRIVER,
-        /* above flags must match REQ_* */
-        BIO_RW_AHEAD,
-        BIO_RW_BARRIER,
-        BIO_RW_SYNCIO,
-        BIO_RW_UNPLUG,
-        BIO_RW_META,
-        BIO_RW_DISCARD,
-        BIO_RW_NOIDLE,
-};
-
-/*
- * First four bits must match between bio->bi_rw and rq->cmd_flags, make
- * that explicit here.
- */
-#define BIO_RW_RQ_MASK          0xf
-
-static inline bool bio_rw_flagged(struct bio *bio, enum bio_rw_flags flag)
-{
-        return (bio->bi_rw & (1 << flag)) != 0;
-}
-
-/*
  * upper 16 bits of bi_rw define the io priority of this bio
  */
 #define BIO_PRIO_SHIFT  (8 * sizeof(unsigned long) - IOPRIO_BITS)
@@ -211,7 +66,10 @@ static inline bool bio_rw_flagged(struct bio *bio, enum bio_rw_flags flag)
 #define bio_offset(bio)         bio_iovec((bio))->bv_offset
 #define bio_segments(bio)       ((bio)->bi_vcnt - (bio)->bi_idx)
 #define bio_sectors(bio)        ((bio)->bi_size >> 9)
-#define bio_empty_barrier(bio)  (bio_rw_flagged(bio, BIO_RW_BARRIER) && !bio_has_data(bio) && !bio_rw_flagged(bio, BIO_RW_DISCARD))
+#define bio_empty_barrier(bio) \
+        ((bio->bi_rw & REQ_HARDBARRIER) && \
+         !bio_has_data(bio) && \
+         !(bio->bi_rw & REQ_DISCARD))
 
 static inline unsigned int bio_cur_bytes(struct bio *bio)
 {
diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h
new file mode 100644
index 000000000000..53691774d34e
--- /dev/null
+++ b/include/linux/blk_types.h
@@ -0,0 +1,194 @@
+/*
+ * Block data types and constants.  Directly include this file only to
+ * break include dependency loop.
+ */
+#ifndef __LINUX_BLK_TYPES_H
+#define __LINUX_BLK_TYPES_H
+
+#ifdef CONFIG_BLOCK
+
+#include <linux/types.h>
+
+struct bio_set;
+struct bio;
+struct bio_integrity_payload;
+struct page;
+struct block_device;
+typedef void (bio_end_io_t) (struct bio *, int);
+typedef void (bio_destructor_t) (struct bio *);
+
+/*
+ * was unsigned short, but we might as well be ready for > 64kB I/O pages
+ */
+struct bio_vec {
+        struct page     *bv_page;
+        unsigned int    bv_len;
+        unsigned int    bv_offset;
+};
+
+/*
+ * main unit of I/O for the block layer and lower layers (ie drivers and
+ * stacking drivers)
+ */
+struct bio {
+        sector_t                bi_sector;      /* device address in 512 byte
+                                                   sectors */
+        struct bio              *bi_next;       /* request queue link */
+        struct block_device     *bi_bdev;
+        unsigned long           bi_flags;       /* status, command, etc */
+        unsigned long           bi_rw;          /* bottom bits READ/WRITE,
+                                                 * top bits priority
+                                                 */
+
+        unsigned short          bi_vcnt;        /* how many bio_vec's */
+        unsigned short          bi_idx;         /* current index into bvl_vec */
+
+        /* Number of segments in this BIO after
+         * physical address coalescing is performed.
+         */
+        unsigned int            bi_phys_segments;
+
+        unsigned int            bi_size;        /* residual I/O count */
+
+        /*
+         * To keep track of the max segment size, we account for the
+         * sizes of the first and last mergeable segments in this bio.
+         */
+        unsigned int            bi_seg_front_size;
+        unsigned int            bi_seg_back_size;
+
+        unsigned int            bi_max_vecs;    /* max bvl_vecs we can hold */
+
+        unsigned int            bi_comp_cpu;    /* completion CPU */
+
+        atomic_t                bi_cnt;         /* pin count */
+
+        struct bio_vec          *bi_io_vec;     /* the actual vec list */
+
+        bio_end_io_t            *bi_end_io;
+
+        void                    *bi_private;
+#if defined(CONFIG_BLK_DEV_INTEGRITY)
+        struct bio_integrity_payload *bi_integrity;  /* data integrity */
+#endif
+
+        bio_destructor_t        *bi_destructor; /* destructor */
+
+        /*
+         * We can inline a number of vecs at the end of the bio, to avoid
+         * double allocations for a small number of bio_vecs. This member
+         * MUST obviously be kept at the very end of the bio.
+         */
+        struct bio_vec          bi_inline_vecs[0];
+};
+
+/*
+ * bio flags
+ */
+#define BIO_UPTODATE    0       /* ok after I/O completion */
+#define BIO_RW_BLOCK    1       /* RW_AHEAD set, and read/write would block */
+#define BIO_EOF         2       /* out-out-bounds error */
+#define BIO_SEG_VALID   3       /* bi_phys_segments valid */
+#define BIO_CLONED      4       /* doesn't own data */
+#define BIO_BOUNCED     5       /* bio is a bounce bio */
+#define BIO_USER_MAPPED 6       /* contains user pages */
+#define BIO_EOPNOTSUPP  7       /* not supported */
+#define BIO_CPU_AFFINE  8       /* complete bio on same CPU as submitted */
+#define BIO_NULL_MAPPED 9       /* contains invalid user pages */
+#define BIO_FS_INTEGRITY 10     /* fs owns integrity data, not block layer */
+#define BIO_QUIET       11      /* Make BIO Quiet */
+#define bio_flagged(bio, flag)  ((bio)->bi_flags & (1 << (flag)))
+
+/*
+ * top 4 bits of bio flags indicate the pool this bio came from
+ */
+#define BIO_POOL_BITS           (4)
+#define BIO_POOL_NONE           ((1UL << BIO_POOL_BITS) - 1)
+#define BIO_POOL_OFFSET         (BITS_PER_LONG - BIO_POOL_BITS)
+#define BIO_POOL_MASK           (1UL << BIO_POOL_OFFSET)
+#define BIO_POOL_IDX(bio)       ((bio)->bi_flags >> BIO_POOL_OFFSET)
+
+#endif /* CONFIG_BLOCK */
+
+/*
+ * Request flags.  For use in the cmd_flags field of struct request, and in
+ * bi_rw of struct bio.  Note that some flags are only valid in either one.
+ */
+enum rq_flag_bits {
+        /* common flags */
+        __REQ_WRITE,            /* not set, read. set, write */
+        __REQ_FAILFAST_DEV,     /* no driver retries of device errors */
+        __REQ_FAILFAST_TRANSPORT, /* no driver retries of transport errors */
+        __REQ_FAILFAST_DRIVER,  /* no driver retries of driver errors */
+
+        __REQ_HARDBARRIER,      /* may not be passed by drive either */
+        __REQ_SYNC,             /* request is sync (sync write or read) */
+        __REQ_META,             /* metadata io request */
+        __REQ_DISCARD,          /* request to discard sectors */
+        __REQ_NOIDLE,           /* don't anticipate more IO after this one */
+
+        /* bio only flags */
+        __REQ_UNPLUG,           /* unplug the immediately after submission */
+        __REQ_RAHEAD,           /* read ahead, can fail anytime */
+
+        /* request only flags */
+        __REQ_SORTED,           /* elevator knows about this request */
+        __REQ_SOFTBARRIER,      /* may not be passed by ioscheduler */
+        __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_ALLOCED,          /* request came from our alloc pool */
+        __REQ_COPY_USER,        /* contains copies of user pages */
+        __REQ_INTEGRITY,        /* integrity metadata has been remapped */
+        __REQ_FLUSH,            /* request for cache flush */
+        __REQ_IO_STAT,          /* account I/O stat */
+        __REQ_MIXED_MERGE,      /* merge of different types, fail separately */
+        __REQ_NR_BITS,          /* stops here */
+};
+
+#define REQ_WRITE               (1 << __REQ_WRITE)
+#define REQ_FAILFAST_DEV        (1 << __REQ_FAILFAST_DEV)
+#define REQ_FAILFAST_TRANSPORT  (1 << __REQ_FAILFAST_TRANSPORT)
+#define REQ_FAILFAST_DRIVER     (1 << __REQ_FAILFAST_DRIVER)
+#define REQ_HARDBARRIER         (1 << __REQ_HARDBARRIER)
+#define REQ_SYNC                (1 << __REQ_SYNC)
+#define REQ_META                (1 << __REQ_META)
+#define REQ_DISCARD             (1 << __REQ_DISCARD)
+#define REQ_NOIDLE              (1 << __REQ_NOIDLE)
+
+#define REQ_FAILFAST_MASK \
+        (REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | REQ_FAILFAST_DRIVER)
+#define REQ_COMMON_MASK \
+        (REQ_WRITE | REQ_FAILFAST_MASK | REQ_HARDBARRIER | REQ_SYNC | \
+         REQ_META| REQ_DISCARD | REQ_NOIDLE)
+
+#define REQ_UNPLUG              (1 << __REQ_UNPLUG)
+#define REQ_RAHEAD              (1 << __REQ_RAHEAD)
+
+#define REQ_SORTED              (1 << __REQ_SORTED)
+#define REQ_SOFTBARRIER         (1 << __REQ_SOFTBARRIER)
+#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_ALLOCED             (1 << __REQ_ALLOCED)
+#define REQ_COPY_USER           (1 << __REQ_COPY_USER)
+#define REQ_INTEGRITY           (1 << __REQ_INTEGRITY)
+#define REQ_FLUSH               (1 << __REQ_FLUSH)
+#define REQ_IO_STAT             (1 << __REQ_IO_STAT)
+#define REQ_MIXED_MERGE         (1 << __REQ_MIXED_MERGE)
+
+#endif /* __LINUX_BLK_TYPES_H */
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 09a840264d6f..89c855c5655c 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -60,7 +60,6 @@ enum rq_cmd_type_bits {
         REQ_TYPE_PM_RESUME,             /* resume request */
         REQ_TYPE_PM_SHUTDOWN,           /* shutdown 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
@@ -70,84 +69,6 @@ enum rq_cmd_type_bits {
         REQ_TYPE_ATA_PC,
 };
 
-/*
- * 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 {
-        REQ_LB_OP_EJECT = 0x40,         /* eject request */
-        REQ_LB_OP_FLUSH = 0x41,         /* flush request */
-};
-
-/*
- * request type modified bits. first four bits match BIO_RW* bits, important
- */
-enum rq_flag_bits {
-        __REQ_RW,               /* not set, read. set, write */
-        __REQ_FAILFAST_DEV,     /* no driver retries of device errors */
-        __REQ_FAILFAST_TRANSPORT, /* no driver retries of transport errors */
-        __REQ_FAILFAST_DRIVER,  /* no driver retries of driver errors */
-        /* above flags must match BIO_RW_* */
-        __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 */
-        __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 (sync write or read) */
-        __REQ_ALLOCED,          /* request came from our alloc pool */
-        __REQ_RW_META,          /* metadata io request */
-        __REQ_COPY_USER,        /* contains copies of user pages */
-        __REQ_INTEGRITY,        /* integrity metadata has been remapped */
-        __REQ_NOIDLE,           /* Don't anticipate more IO after this one */
-        __REQ_IO_STAT,          /* account I/O stat */
-        __REQ_MIXED_MERGE,      /* merge of different types, fail separately */
-        __REQ_NR_BITS,          /* stops here */
-};
-
-#define REQ_RW          (1 << __REQ_RW)
-#define REQ_FAILFAST_DEV        (1 << __REQ_FAILFAST_DEV)
-#define REQ_FAILFAST_TRANSPORT  (1 << __REQ_FAILFAST_TRANSPORT)
-#define REQ_FAILFAST_DRIVER     (1 << __REQ_FAILFAST_DRIVER)
-#define REQ_DISCARD     (1 << __REQ_DISCARD)
-#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 REQ_COPY_USER   (1 << __REQ_COPY_USER)
-#define REQ_INTEGRITY   (1 << __REQ_INTEGRITY)
-#define REQ_NOIDLE      (1 << __REQ_NOIDLE)
-#define REQ_IO_STAT     (1 << __REQ_IO_STAT)
-#define REQ_MIXED_MERGE (1 << __REQ_MIXED_MERGE)
-
-#define REQ_FAILFAST_MASK       (REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | \
-                                 REQ_FAILFAST_DRIVER)
-
 #define BLK_MAX_CDB     16
 
 /*
@@ -264,6 +185,7 @@ struct request_pm_state
 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 (unprep_rq_fn) (struct request_queue *, struct request *);
 typedef void (unplug_fn) (struct request_queue *);
 
 struct bio_vec;
@@ -275,7 +197,6 @@ struct bvec_merge_data {
 };
 typedef int (merge_bvec_fn) (struct request_queue *, struct bvec_merge_data *,
                              struct bio_vec *);
-typedef void (prepare_flush_fn) (struct request_queue *, struct request *);
 typedef void (softirq_done_fn)(struct request *);
 typedef int (dma_drain_needed_fn)(struct request *);
 typedef int (lld_busy_fn) (struct request_queue *q);
@@ -346,9 +267,9 @@ struct request_queue
         request_fn_proc         *request_fn;
         make_request_fn         *make_request_fn;
         prep_rq_fn              *prep_rq_fn;
+        unprep_rq_fn            *unprep_rq_fn;
         unplug_fn               *unplug_fn;
         merge_bvec_fn           *merge_bvec_fn;
-        prepare_flush_fn        *prepare_flush_fn;
         softirq_done_fn         *softirq_done_fn;
         rq_timed_out_fn         *rq_timed_out_fn;
         dma_drain_needed_fn     *dma_drain_needed;
@@ -467,11 +388,13 @@ struct request_queue
 #define QUEUE_FLAG_IO_STAT     15       /* do IO stats */
 #define QUEUE_FLAG_DISCARD     16       /* supports DISCARD */
 #define QUEUE_FLAG_NOXMERGES   17       /* No extended merges */
+#define QUEUE_FLAG_ADD_RANDOM  18       /* Contributes to random pool */
 
 #define QUEUE_FLAG_DEFAULT      ((1 << QUEUE_FLAG_IO_STAT) |            \
                                  (1 << QUEUE_FLAG_CLUSTER) |            \
                                  (1 << QUEUE_FLAG_STACKABLE)    |       \
-                                 (1 << QUEUE_FLAG_SAME_COMP))
+                                 (1 << QUEUE_FLAG_SAME_COMP)    |       \
+                                 (1 << QUEUE_FLAG_ADD_RANDOM))
 
 static inline int queue_is_locked(struct request_queue *q)
 {
@@ -596,38 +519,26 @@ enum {
         test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags)
 #define blk_queue_nonrot(q)     test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags)
 #define blk_queue_io_stat(q)    test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags)
+#define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags)
 #define blk_queue_flushing(q)   ((q)->ordseq)
 #define blk_queue_stackable(q)  \
         test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags)
 #define blk_queue_discard(q)    test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags)
 
-#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_failfast_dev(rq)    ((rq)->cmd_flags & REQ_FAILFAST_DEV)
-#define blk_failfast_transport(rq) ((rq)->cmd_flags & REQ_FAILFAST_TRANSPORT)
-#define blk_failfast_driver(rq) ((rq)->cmd_flags & REQ_FAILFAST_DRIVER)
-#define blk_noretry_request(rq) (blk_failfast_dev(rq) ||        \
-                                 blk_failfast_transport(rq) ||  \
-                                 blk_failfast_driver(rq))
-#define blk_rq_started(rq)      ((rq)->cmd_flags & REQ_STARTED)
-#define blk_rq_io_stat(rq)      ((rq)->cmd_flags & REQ_IO_STAT)
-#define blk_rq_quiet(rq)        ((rq)->cmd_flags & REQ_QUIET)
-
-#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)
+#define blk_noretry_request(rq) \
+        ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \
+                             REQ_FAILFAST_DRIVER))
+
+#define blk_account_rq(rq) \
+        (((rq)->cmd_flags & REQ_STARTED) && \
+         ((rq)->cmd_type == REQ_TYPE_FS || \
+          ((rq)->cmd_flags & REQ_DISCARD)))
+
 #define blk_pm_request(rq)      \
-        (blk_pm_suspend_request(rq) || blk_pm_resume_request(rq))
+        ((rq)->cmd_type == REQ_TYPE_PM_SUSPEND || \
+         (rq)->cmd_type == REQ_TYPE_PM_RESUME)
 
 #define blk_rq_cpu_valid(rq)    ((rq)->cpu != -1)
-#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)
 /* rq->queuelist of dequeued request must be list_empty() */
 #define blk_queued_rq(rq)       (!list_empty(&(rq)->queuelist))
@@ -641,7 +552,7 @@ enum {
  */
 static inline bool rw_is_sync(unsigned int rw_flags)
 {
-        return !(rw_flags & REQ_RW) || (rw_flags & REQ_RW_SYNC);
+        return !(rw_flags & REQ_WRITE) || (rw_flags & REQ_SYNC);
 }
 
 static inline bool rq_is_sync(struct request *rq)
@@ -649,9 +560,6 @@ static inline bool rq_is_sync(struct request *rq)
         return rw_is_sync(rq->cmd_flags);
 }
 
-#define rq_is_meta(rq)          ((rq)->cmd_flags & REQ_RW_META)
-#define rq_noidle(rq)           ((rq)->cmd_flags & REQ_NOIDLE)
-
 static inline int blk_queue_full(struct request_queue *q, int sync)
 {
         if (sync)
@@ -684,7 +592,8 @@ static inline void blk_clear_queue_full(struct request_queue *q, int sync)
         (REQ_NOMERGE | REQ_STARTED | REQ_HARDBARRIER | REQ_SOFTBARRIER)
 #define rq_mergeable(rq)        \
         (!((rq)->cmd_flags & RQ_NOMERGE_FLAGS) && \
-         (blk_discard_rq(rq) || blk_fs_request((rq))))
+         (((rq)->cmd_flags & REQ_DISCARD) || \
+          (rq)->cmd_type == REQ_TYPE_FS))
 
 /*
  * q->prep_rq_fn return values
@@ -709,7 +618,7 @@ extern unsigned long blk_max_low_pfn, blk_max_pfn;
 #define BLK_BOUNCE_HIGH         -1ULL
 #endif
 #define BLK_BOUNCE_ANY          (-1ULL)
-#define BLK_BOUNCE_ISA          (ISA_DMA_THRESHOLD)
+#define BLK_BOUNCE_ISA          (DMA_BIT_MASK(24))
 
 /*
  * default timeout for SG_IO if none specified
@@ -781,6 +690,8 @@ extern struct request *blk_make_request(struct request_queue *, struct bio *,
                                         gfp_t);
 extern void blk_insert_request(struct request_queue *, struct request *, int, void *);
 extern void blk_requeue_request(struct request_queue *, struct request *);
+extern void blk_add_request_payload(struct request *rq, struct page *page,
+                unsigned int len);
 extern int blk_rq_check_limits(struct request_queue *q, struct request *rq);
 extern int blk_lld_busy(struct request_queue *q);
 extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src,
@@ -915,6 +826,7 @@ extern void blk_complete_request(struct request *);
 extern void __blk_complete_request(struct request *);
 extern void blk_abort_request(struct request *);
 extern void blk_abort_queue(struct request_queue *);
+extern void blk_unprep_request(struct request *);
 
 /*
  * Access functions for manipulating queue properties
@@ -959,6 +871,7 @@ extern int blk_queue_dma_drain(struct request_queue *q,
 extern void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn);
 extern void blk_queue_segment_boundary(struct request_queue *, unsigned long);
 extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn);
+extern void blk_queue_unprep_rq(struct request_queue *, unprep_rq_fn *ufn);
 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);
@@ -966,7 +879,7 @@ extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *);
 extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *);
 extern void blk_queue_rq_timeout(struct request_queue *, unsigned int);
 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_queue_ordered(struct request_queue *, unsigned);
 extern bool blk_do_ordered(struct request_queue *, struct request **);
 extern unsigned blk_ordered_cur_seq(struct request_queue *);
 extern unsigned blk_ordered_req_seq(struct request *);
@@ -1020,7 +933,7 @@ static inline int sb_issue_discard(struct super_block *sb,
 {
         block <<= (sb->s_blocksize_bits - 9);
         nr_blocks <<= (sb->s_blocksize_bits - 9);
-        return blkdev_issue_discard(sb->s_bdev, block, nr_blocks, GFP_KERNEL,
+        return blkdev_issue_discard(sb->s_bdev, block, nr_blocks, GFP_NOFS,
                                    BLKDEV_IFL_WAIT | BLKDEV_IFL_BARRIER);
 }
 
@@ -1333,7 +1246,6 @@ static inline int blk_integrity_rq(struct request *rq)
 struct block_device_operations {
         int (*open) (struct block_device *, fmode_t);
         int (*release) (struct gendisk *, fmode_t);
-        int (*locked_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
         int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
         int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
         int (*direct_access) (struct block_device *, sector_t,
diff --git a/include/linux/blktrace_api.h b/include/linux/blktrace_api.h
index 416bf62d6d46..3395cf7130f5 100644
--- a/include/linux/blktrace_api.h
+++ b/include/linux/blktrace_api.h
@@ -5,6 +5,7 @@
 #ifdef __KERNEL__
 #include <linux/blkdev.h>
 #include <linux/relay.h>
+#include <linux/compat.h>
 #endif
 
 /*
@@ -220,11 +221,26 @@ static inline int blk_trace_init_sysfs(struct device *dev)
 
 #endif /* CONFIG_BLK_DEV_IO_TRACE */
 
+#ifdef CONFIG_COMPAT
+
+struct compat_blk_user_trace_setup {
+        char name[32];
+        u16 act_mask;
+        u32 buf_size;
+        u32 buf_nr;
+        compat_u64 start_lba;
+        compat_u64 end_lba;
+        u32 pid;
+};
+#define BLKTRACESETUP32 _IOWR(0x12, 115, struct compat_blk_user_trace_setup)
+
+#endif
+
 #if defined(CONFIG_EVENT_TRACING) && defined(CONFIG_BLOCK)
 
 static inline int blk_cmd_buf_len(struct request *rq)
 {
-        return blk_pc_request(rq) ? rq->cmd_len * 3 : 1;
+        return (rq->cmd_type == REQ_TYPE_BLOCK_PC) ? rq->cmd_len * 3 : 1;
 }
 
 extern void blk_dump_cmd(char *buf, struct request *rq);
diff --git a/include/linux/coda_psdev.h b/include/linux/coda_psdev.h
index 8859e2ede9fe..284b520934a0 100644
--- a/include/linux/coda_psdev.h
+++ b/include/linux/coda_psdev.h
@@ -86,9 +86,9 @@ struct upc_req {
         wait_queue_head_t   uc_sleep;   /* process' wait queue */
 };
 
-#define REQ_ASYNC  0x1
-#define REQ_READ   0x2
-#define REQ_WRITE  0x4
-#define REQ_ABORT  0x8
+#define CODA_REQ_ASYNC  0x1
+#define CODA_REQ_READ   0x2
+#define CODA_REQ_WRITE  0x4
+#define CODA_REQ_ABORT  0x8
 
 #endif
diff --git a/include/linux/drbd.h b/include/linux/drbd.h
index b8d2516668aa..479ee3a1d901 100644
--- a/include/linux/drbd.h
+++ b/include/linux/drbd.h
@@ -53,7 +53,7 @@
 
 
 extern const char *drbd_buildtag(void);
-#define REL_VERSION "8.3.8"
+#define REL_VERSION "8.3.8.1"
 #define API_VERSION 88
 #define PRO_VERSION_MIN 86
 #define PRO_VERSION_MAX 94
diff --git a/include/linux/drbd_nl.h b/include/linux/drbd_nl.h
index ce77a746fc9d..5f042810a56c 100644
--- a/include/linux/drbd_nl.h
+++ b/include/linux/drbd_nl.h
@@ -78,10 +78,11 @@ NL_PACKET(syncer_conf, 8,
         NL_INTEGER(     30,     T_MAY_IGNORE,   rate)
         NL_INTEGER(     31,     T_MAY_IGNORE,   after)
         NL_INTEGER(     32,     T_MAY_IGNORE,   al_extents)
-        NL_INTEGER(     71,     T_MAY_IGNORE,   dp_volume)
-        NL_INTEGER(     72,     T_MAY_IGNORE,   dp_interval)
-        NL_INTEGER(     73,     T_MAY_IGNORE,   throttle_th)
-        NL_INTEGER(     74,     T_MAY_IGNORE,   hold_off_th)
+/*      NL_INTEGER(     71,     T_MAY_IGNORE,   dp_volume)
+ *      NL_INTEGER(     72,     T_MAY_IGNORE,   dp_interval)
+ *      NL_INTEGER(     73,     T_MAY_IGNORE,   throttle_th)
+ *      NL_INTEGER(     74,     T_MAY_IGNORE,   hold_off_th)
+ * feature will be reimplemented differently with 8.3.9 */
         NL_STRING(      52,     T_MAY_IGNORE,   verify_alg,     SHARED_SECRET_MAX)
         NL_STRING(      51,     T_MAY_IGNORE,   cpu_mask,       32)
         NL_STRING(      64,     T_MAY_IGNORE,   csums_alg,      SHARED_SECRET_MAX)
diff --git a/include/linux/fs.h b/include/linux/fs.h
index a8ccf85b8691..1542e0e52b2e 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -8,6 +8,7 @@
 
 #include <linux/limits.h>
 #include <linux/ioctl.h>
+#include <linux/blk_types.h>
 
 /*
  * It's silly to have NR_OPEN bigger than NR_FILE, but you can change
@@ -121,7 +122,7 @@ struct inodes_stat_t {
  *                      immediately wait on this read without caring about
  *                      unplugging.
  * READA                Used for read-ahead operations. Lower priority, and the
- *                       block layer could (in theory) choose to ignore this
+ *                      block layer could (in theory) choose to ignore this
  *                      request if it runs into resource problems.
  * WRITE                A normal async write. Device will be plugged.
  * SWRITE               Like WRITE, but a special case for ll_rw_block() that
@@ -140,7 +141,7 @@ struct inodes_stat_t {
  * SWRITE_SYNC
  * SWRITE_SYNC_PLUG     Like WRITE_SYNC/WRITE_SYNC_PLUG, but locks the buffer.
  *                      See SWRITE.
- * WRITE_BARRIER        Like WRITE, but tells the block layer that all
+ * WRITE_BARRIER        Like WRITE_SYNC, but tells the block layer that all
  *                      previously submitted writes must be safely on storage
  *                      before this one is started. Also guarantees that when
  *                      this write is complete, it itself is also safely on
@@ -148,29 +149,31 @@ struct inodes_stat_t {
  *                      of this IO.
  *
  */
-#define RW_MASK         1
-#define RWA_MASK        2
-#define READ 0
-#define WRITE 1
-#define READA 2         /* read-ahead  - don't block if no resources */
-#define SWRITE 3        /* for ll_rw_block() - wait for buffer lock */
-#define READ_SYNC       (READ | (1 << BIO_RW_SYNCIO) | (1 << BIO_RW_UNPLUG))
-#define READ_META       (READ | (1 << BIO_RW_META))
-#define WRITE_SYNC_PLUG (WRITE | (1 << BIO_RW_SYNCIO) | (1 << BIO_RW_NOIDLE))
-#define WRITE_SYNC      (WRITE_SYNC_PLUG | (1 << BIO_RW_UNPLUG))
-#define WRITE_ODIRECT_PLUG      (WRITE | (1 << BIO_RW_SYNCIO))
-#define WRITE_META      (WRITE | (1 << BIO_RW_META))
-#define SWRITE_SYNC_PLUG        \
-                        (SWRITE | (1 << BIO_RW_SYNCIO) | (1 << BIO_RW_NOIDLE))
-#define SWRITE_SYNC     (SWRITE_SYNC_PLUG | (1 << BIO_RW_UNPLUG))
-#define WRITE_BARRIER   (WRITE | (1 << BIO_RW_BARRIER))
+#define RW_MASK                 REQ_WRITE
+#define RWA_MASK                REQ_RAHEAD
+
+#define READ                    0
+#define WRITE                   RW_MASK
+#define READA                   RWA_MASK
+#define SWRITE                  (WRITE | READA)
+
+#define READ_SYNC               (READ | REQ_SYNC | REQ_UNPLUG)
+#define READ_META               (READ | REQ_META)
+#define WRITE_SYNC_PLUG         (WRITE | REQ_SYNC | REQ_NOIDLE)
+#define WRITE_SYNC              (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_UNPLUG)
+#define WRITE_ODIRECT_PLUG      (WRITE | REQ_SYNC)
+#define WRITE_META              (WRITE | REQ_META)
+#define WRITE_BARRIER           (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_UNPLUG | \
+                                 REQ_HARDBARRIER)
+#define SWRITE_SYNC_PLUG        (SWRITE | REQ_SYNC | REQ_NOIDLE)
+#define SWRITE_SYNC             (SWRITE | REQ_SYNC | REQ_NOIDLE | REQ_UNPLUG)
 
 /*
  * These aren't really reads or writes, they pass down information about
  * parts of device that are now unused by the file system.
  */
-#define DISCARD_NOBARRIER (WRITE | (1 << BIO_RW_DISCARD))
-#define DISCARD_BARRIER (DISCARD_NOBARRIER | (1 << BIO_RW_BARRIER))
+#define DISCARD_NOBARRIER       (WRITE | REQ_DISCARD)
+#define DISCARD_BARRIER         (WRITE | REQ_DISCARD | REQ_HARDBARRIER)
 
 #define SEL_IN          1
 #define SEL_OUT         2
@@ -2196,7 +2199,6 @@ static inline void insert_inode_hash(struct inode *inode) {
 extern void file_move(struct file *f, struct list_head *list);
 extern void file_kill(struct file *f);
 #ifdef CONFIG_BLOCK
-struct bio;
 extern void submit_bio(int, struct bio *);
 extern int bdev_read_only(struct block_device *);
 #endif
@@ -2263,7 +2265,6 @@ static inline int xip_truncate_page(struct address_space *mapping, loff_t from)
 #endif
 
 #ifdef CONFIG_BLOCK
-struct bio;
 typedef void (dio_submit_t)(int rw, struct bio *bio, struct inode *inode,
                             loff_t file_offset);