X-Git-Url: https://git.camperquake.de/gitweb.cgi?a=blobdiff_plain;f=include%2Flinux%2Fblkdev_compat.h;h=47f569bbdaae2529b21d07cd74f623b1b0810eda;hb=0377189b884fab7db02a95088e05712c7cf336f7;hp=0a7c985d8ad58fcdf5598a5b2d9ee2506e32c287;hpb=96801d290652812780cf6c070729154d4af8e1ce;p=zfs.git

diff --git a/include/linux/blkdev_compat.h b/include/linux/blkdev_compat.h
index 0a7c985..47f569b 100644
--- a/include/linux/blkdev_compat.h
+++ b/include/linux/blkdev_compat.h
@@ -132,6 +132,23 @@ blk_end_request_x(struct request *req, int error, unsigned int nr_bytes)
 # endif /* HAVE_BLK_END_REQUEST_GPL_ONLY */
 #endif /* HAVE_BLK_END_REQUEST */
 
+/*
+ * 2.6.36 API change,
+ * The blk_queue_flush() interface has replaced blk_queue_ordered()
+ * interface.  However, while the old interface was available to all the
+ * new one is GPL-only.   Thus if the GPL-only version is detected we
+ * implement our own trivial helper compatibility funcion.   The hope is
+ * that long term this function will be opened up.
+ */
+#if defined(HAVE_BLK_QUEUE_FLUSH) && defined(HAVE_BLK_QUEUE_FLUSH_GPL_ONLY)
+#define blk_queue_flush __blk_queue_flush
+static inline void
+__blk_queue_flush(struct request_queue *q, unsigned int flags)
+{
+	q->flush_flags = flags & (REQ_FLUSH | REQ_FUA);
+}
+#endif /* HAVE_BLK_QUEUE_FLUSH && HAVE_BLK_QUEUE_FLUSH_GPL_ONLY */
+
 #ifndef HAVE_BLK_RQ_POS
 static inline sector_t
 blk_rq_pos(struct request *req)
@@ -183,6 +200,53 @@ __blk_rq_bytes(struct request *req)
 #define blk_queue_stackable(q)	((q)->request_fn == NULL)
 #endif
 
+/*
+ * 2.6.34 API change,
+ * The blk_queue_max_hw_sectors() function replaces blk_queue_max_sectors().
+ */
+#ifndef HAVE_BLK_QUEUE_MAX_HW_SECTORS
+#define blk_queue_max_hw_sectors __blk_queue_max_hw_sectors
+static inline void
+__blk_queue_max_hw_sectors(struct request_queue *q, unsigned int max_hw_sectors)
+{
+	blk_queue_max_sectors(q, max_hw_sectors);
+}
+#endif
+
+/*
+ * 2.6.34 API change,
+ * The blk_queue_max_segments() function consolidates
+ * blk_queue_max_hw_segments() and blk_queue_max_phys_segments().
+ */
+#ifndef HAVE_BLK_QUEUE_MAX_SEGMENTS
+#define blk_queue_max_segments __blk_queue_max_segments
+static inline void
+__blk_queue_max_segments(struct request_queue *q, unsigned short max_segments)
+{
+	blk_queue_max_phys_segments(q, max_segments);
+	blk_queue_max_hw_segments(q, max_segments);
+}
+#endif
+
+/*
+ * 2.6.30 API change,
+ * The blk_queue_physical_block_size() function was introduced to
+ * indicate the smallest I/O the device can write without incurring
+ * a read-modify-write penalty.  For older kernels this is a no-op.
+ */
+#ifndef HAVE_BLK_QUEUE_PHYSICAL_BLOCK_SIZE
+#define blk_queue_physical_block_size(q, x)	((void)(0))
+#endif
+
+/*
+ * 2.6.30 API change,
+ * The blk_queue_io_opt() function was added to indicate the optimal
+ * I/O size for the device.  For older kernels this is a no-op.
+ */
+#ifndef HAVE_BLK_QUEUE_IO_OPT
+#define blk_queue_io_opt(q, x)			((void)(0))
+#endif
+
 #ifndef HAVE_GET_DISK_RO
 static inline int
 get_disk_ro(struct gendisk *disk)
@@ -329,14 +393,37 @@ bio_set_flags_failfast(struct block_device *bdev, int *flags)
 #endif /* HAVE_1ARG_INVALIDATE_BDEV */
 
 /*
+ * 2.6.27 API change
+ * The function was exported for use, prior to this it existed by the
+ * symbol was not exported.
+ */
+#ifndef HAVE_LOOKUP_BDEV
+# define lookup_bdev(path)		ERR_PTR(-ENOTSUP)
+#endif
+
+/*
  * 2.6.30 API change
- * Change to make it explicit there this is the logical block size.
+ * To ensure good performance preferentially use the physical block size
+ * for proper alignment.  The physical size is supposed to be the internal
+ * sector size used by the device.  This is often 4096 byte for AF devices,
+ * while a smaller 512 byte logical size is supported for compatibility.
+ *
+ * Unfortunately, many drives still misreport their physical sector size.
+ * For devices which are known to lie you may need to manually set this
+ * at pool creation time with 'zpool create -o ashift=12 ...'.
+ *
+ * When the physical block size interface isn't available, we fall back to
+ * the logical block size interface and then the older hard sector size.
  */
-#ifdef HAVE_BDEV_LOGICAL_BLOCK_SIZE
-# define vdev_bdev_block_size(bdev)	bdev_logical_block_size(bdev)
+#ifdef HAVE_BDEV_PHYSICAL_BLOCK_SIZE
+# define vdev_bdev_block_size(bdev)	bdev_physical_block_size(bdev)
 #else
-# define vdev_bdev_block_size(bdev)	bdev_hardsect_size(bdev)
-#endif
+# ifdef HAVE_BDEV_LOGICAL_BLOCK_SIZE
+#  define vdev_bdev_block_size(bdev)	bdev_logical_block_size(bdev)
+# else
+#  define vdev_bdev_block_size(bdev)	bdev_hardsect_size(bdev)
+# endif /* HAVE_BDEV_LOGICAL_BLOCK_SIZE */
+#endif /* HAVE_BDEV_PHYSICAL_BLOCK_SIZE */
 
 /*
  * 2.6.37 API change
@@ -345,14 +432,45 @@ bio_set_flags_failfast(struct block_device *bdev, int *flags)
  * allow richer semantics to be expressed to the block layer.  It is
  * the block layers responsibility to choose the correct way to
  * implement these semantics.
+ *
+ * The existence of these flags implies that REQ_FLUSH an REQ_FUA are
+ * defined.  Thus we can safely define VDEV_REQ_FLUSH and VDEV_REQ_FUA
+ * compatibility macros.
  */
 #ifdef WRITE_FLUSH_FUA
 # define VDEV_WRITE_FLUSH_FUA		WRITE_FLUSH_FUA
+# define VDEV_REQ_FLUSH			REQ_FLUSH
+# define VDEV_REQ_FUA			REQ_FUA
 #else
 # define VDEV_WRITE_FLUSH_FUA		WRITE_BARRIER
+# define VDEV_REQ_FLUSH			REQ_HARDBARRIER
+# define VDEV_REQ_FUA			REQ_HARDBARRIER
 #endif
 
 /*
+ * 2.6.32 API change
+ * Use the normal I/O patch for discards.
+ */
+#ifdef REQ_DISCARD
+# define VDEV_REQ_DISCARD		REQ_DISCARD
+#endif
+
+/*
+ * 2.6.33 API change
+ * Discard granularity and alignment restrictions may now be set.  For
+ * older kernels which do not support this it is safe to skip it.
+ */
+#ifdef HAVE_DISCARD_GRANULARITY
+static inline void
+blk_queue_discard_granularity(struct request_queue *q, unsigned int dg)
+{
+	q->limits.discard_granularity = dg;
+}
+#else
+#define blk_queue_discard_granularity(x, dg)	((void)0)
+#endif /* HAVE_DISCARD_GRANULARITY */
+
+/*
  * Default Linux IO Scheduler,
  * Setting the scheduler to noop will allow the Linux IO scheduler to
  * still perform front and back merging, while leaving the request
@@ -360,4 +478,13 @@ bio_set_flags_failfast(struct block_device *bdev, int *flags)
  */
 #define	VDEV_SCHEDULER			"noop"
 
+/*
+ * A common holder for vdev_bdev_open() is used to relax the exclusive open
+ * semantics slightly.  Internal vdev disk callers may pass VDEV_HOLDER to
+ * allow them to open the device multiple times.  Other kernel callers and
+ * user space processes which don't pass this value will get EBUSY.  This is
+ * currently required for the correct operation of hot spares.
+ */
+#define VDEV_HOLDER			((void *)0x2f5401de7)
+
 #endif /* _ZFS_BLKDEV_H */