Change default block size for user VBLK device access from 2K to PAGE_SIZE

    (4K on an i386, 8K on an alpha).

    Make BLKDEV_IOSIZE, DFLTPHYS, and MAXPHYS kernel-configurable.

6 files changed, 75 insertions, 2 deletions

diff --git a/sys/alpha/include/param.h b/sys/alpha/include/param.h
index 873ea8504b4f..2bb660ca4cb7 100644
--- a/sys/alpha/include/param.h
+++ b/sys/alpha/include/param.h
@@ -98,9 +98,16 @@
 #define	DEV_BSHIFT	9		/* log2(DEV_BSIZE) */
 #define	DEV_BSIZE	(1<<DEV_BSHIFT)
 
-#define BLKDEV_IOSIZE	2048
+#ifndef BLKDEV_IOSIZE
+#define BLKDEV_IOSIZE  PAGE_SIZE	/* default block device I/O size */
+#endif
+
+#ifndef DFLTPHYS
 #define DFLTPHYS	(64 * 1024)	/* default max raw I/O transfer size */
+#endif
+#ifndef MAXPHYS
 #define MAXPHYS		(128 * 1024)	/* max raw I/O transfer size */
+#endif
 
 #define	CLSIZE		1
 #define	CLSIZELOG2	0
diff --git a/sys/conf/NOTES b/sys/conf/NOTES
index 08f9f8cbbdc2..f6fe5cf6b9df 100644
--- a/sys/conf/NOTES
+++ b/sys/conf/NOTES
@@ -56,6 +56,25 @@ maxusers	10
 options 	MAXDSIZ="(256*1024*1024)"
 options 	DFLDSIZ="(256*1024*1024)"
 
+# 
+# BLKDEV_IOSIZE sets the default block size used in user block
+# device I/O.  Note that this value will be overriden by the label
+# when specifying a block device from a label with a non-0 
+# partition blocksize
+#
+# DFLTPHYS is the default maximum physical I/O transaction size
+# and is used mostly by the clustering code.  It must be a 
+# multiple of the system page size.
+#
+# MAXPHYS is the absolute maximum physical I/O transaction size.
+# It must be a multiple of the system page size.
+#
+# In general you should not modify either DFLTPHYS or MAXPHYS.
+#
+options		BLKDEV_IOSIZE=8192
+options		DFLTPHYS="(64*1024)"
+options		MAXPHYS="(128*1024)"
+
 # Options for the VM subsystem
 #options 	PQ_NOOPT		# No coloring
 options 	PQ_LARGECACHE		# color for 512k/16k cache
diff --git a/sys/conf/options b/sys/conf/options
index d29884b0b9b7..3384d3789b53 100644
--- a/sys/conf/options
+++ b/sys/conf/options
@@ -288,6 +288,9 @@ INVARIANT_SUPPORT	opt_global.h
 INVARIANTS		opt_global.h
 SIMPLELOCK_DEBUG	opt_global.h
 VFS_BIO_DEBUG		opt_global.h
+BLKDEV_IOSIZE		opt_global.h
+DFLTPHYS		opt_global.h
+MAXPHYS			opt_global.h
 
 # These are VM related options
 VM_KMEM_SIZE	opt_vm.h
diff --git a/sys/i386/conf/LINT b/sys/i386/conf/LINT
index 08f9f8cbbdc2..f6fe5cf6b9df 100644
--- a/sys/i386/conf/LINT
+++ b/sys/i386/conf/LINT
@@ -56,6 +56,25 @@ maxusers	10
 options 	MAXDSIZ="(256*1024*1024)"
 options 	DFLDSIZ="(256*1024*1024)"
 
+# 
+# BLKDEV_IOSIZE sets the default block size used in user block
+# device I/O.  Note that this value will be overriden by the label
+# when specifying a block device from a label with a non-0 
+# partition blocksize
+#
+# DFLTPHYS is the default maximum physical I/O transaction size
+# and is used mostly by the clustering code.  It must be a 
+# multiple of the system page size.
+#
+# MAXPHYS is the absolute maximum physical I/O transaction size.
+# It must be a multiple of the system page size.
+#
+# In general you should not modify either DFLTPHYS or MAXPHYS.
+#
+options		BLKDEV_IOSIZE=8192
+options		DFLTPHYS="(64*1024)"
+options		MAXPHYS="(128*1024)"
+
 # Options for the VM subsystem
 #options 	PQ_NOOPT		# No coloring
 options 	PQ_LARGECACHE		# color for 512k/16k cache
diff --git a/sys/i386/conf/NOTES b/sys/i386/conf/NOTES
index 08f9f8cbbdc2..f6fe5cf6b9df 100644
--- a/sys/i386/conf/NOTES
+++ b/sys/i386/conf/NOTES
@@ -56,6 +56,25 @@ maxusers	10
 options 	MAXDSIZ="(256*1024*1024)"
 options 	DFLDSIZ="(256*1024*1024)"
 
+# 
+# BLKDEV_IOSIZE sets the default block size used in user block
+# device I/O.  Note that this value will be overriden by the label
+# when specifying a block device from a label with a non-0 
+# partition blocksize
+#
+# DFLTPHYS is the default maximum physical I/O transaction size
+# and is used mostly by the clustering code.  It must be a 
+# multiple of the system page size.
+#
+# MAXPHYS is the absolute maximum physical I/O transaction size.
+# It must be a multiple of the system page size.
+#
+# In general you should not modify either DFLTPHYS or MAXPHYS.
+#
+options		BLKDEV_IOSIZE=8192
+options		DFLTPHYS="(64*1024)"
+options		MAXPHYS="(128*1024)"
+
 # Options for the VM subsystem
 #options 	PQ_NOOPT		# No coloring
 options 	PQ_LARGECACHE		# color for 512k/16k cache
diff --git a/sys/i386/include/param.h b/sys/i386/include/param.h
index 1a8b1a724b95..0bd98e4e63b3 100644
--- a/sys/i386/include/param.h
+++ b/sys/i386/include/param.h
@@ -91,9 +91,15 @@
 #define DEV_BSHIFT	9		/* log2(DEV_BSIZE) */
 #define DEV_BSIZE	(1<<DEV_BSHIFT)
 
-#define BLKDEV_IOSIZE	2048
+#ifndef BLKDEV_IOSIZE
+#define BLKDEV_IOSIZE	PAGE_SIZE	/* default block device I/O size */
+#endif
+#ifndef DFLTPHYS
 #define DFLTPHYS	(64 * 1024)	/* default max raw I/O transfer size */
+#endif
+#ifndef MAXPHYS
 #define MAXPHYS		(128 * 1024)	/* max raw I/O transfer size */
+#endif
 
 #define IOPAGES	2		/* pages of i/o permission bitmap */
 #define UPAGES	2		/* pages of u-area */