1999-07-20 Roland McGrath <roland@baalperazim.frob.com>

	* ext2_file_io.c, ffs_file_io.c, minix_file_io.c: Remove fs-specific
	routines *_page_{read,write}_file_direct.  Moved to ...
	* file_io.c (page_read_file_direct, page_write_file_direct): Don't
	call fs-specific routine, these are not fs-specific.  Instead,
	replaced with former fs-specific routines (which were all identical).
	Read and write more than a fs block when disk blocks are contiguous.

1 files changed, 128 insertions, 36 deletions

diff --git a/serverboot/file_io.c b/serverboot/file_io.c
index 141fdcfe..99966f95 100644
--- a/serverboot/file_io.c
+++ b/serverboot/file_io.c
@@ -1,4 +1,4 @@
-/* 
+/*
  * Copyright (c) 1994 The University of Utah and
  * the Computer Systems Laboratory at the University of Utah (CSL).
  * All rights reserved.
@@ -156,41 +156,6 @@ add_file_direct(fdp, fp)
 	}
 }
 
-int
-page_read_file_direct(fdp, offset, size, addr, size_read)
-	register struct file_direct *fdp;
-	vm_offset_t offset;
-	vm_size_t size;
-	vm_offset_t *addr;			/* out */
-	mach_msg_type_number_t *size_read;	/* out */
-{
-	switch (fdp->f_fstype) {
-		case	EXT2_FS:
-				return ext2_page_read_file_direct(fdp, offset, size, addr, size_read);
-		case	MINIX_FS:
-				return minix_page_read_file_direct(fdp, offset, size, addr, size_read);
-		default:
-				return ffs_page_read_file_direct(fdp, offset, size, addr, size_read);
-	}
-}
-
-int
-page_write_file_direct(fdp, offset, addr, size, size_written)
-	register struct file_direct *fdp;
-	vm_offset_t offset;
-	vm_offset_t addr;
-	vm_size_t size;
-	vm_offset_t *size_written;	/* out */
-{
-	switch (fdp->f_fstype) {
-		case	EXT2_FS:
-				return ext2_page_write_file_direct(fdp, offset, addr, size, size_written);
-		case	MINIX_FS:
-				return minix_page_write_file_direct(fdp, offset, addr, size, size_written);
-		default:
-				return ffs_page_write_file_direct(fdp, offset, addr, size, size_written);
-	}
-}
 
 int
 remove_file_direct(fdp)
@@ -223,3 +188,130 @@ file_is_structured(fp)
 			return (fp)->u.ffs.ffs_fs != 0;
 	}
 }
+
+/*
+ * Special read and write routines for default pager.
+ * Assume that all offsets and sizes are multiples
+ * of DEV_BSIZE.
+ */
+
+#define	fdir_blkoff(fdp, offset)	/* offset % fd_bsize */ \
+	((offset) & ((fdp)->fd_bsize - 1))
+#define	fdir_lblkno(fdp, offset)	/* offset / fd_bsize */ \
+	((offset) >> (fdp)->fd_bshift)
+
+#define	fdir_fsbtodb(fdp, block)	/* offset * fd_bsize / DEV_BSIZE */ \
+	((block) << (fdp)->fd_fsbtodb)
+
+/*
+ * Read all or part of a data block, and
+ * return a pointer to the appropriate part.
+ * Caller must deallocate the block when done.
+ */
+int
+page_read_file_direct(fdp, offset, size, addr, size_read)
+	register struct file_direct *fdp;
+	vm_offset_t offset;
+	vm_size_t size;
+	vm_offset_t *addr;			/* out */
+	mach_msg_type_number_t *size_read;	/* out */
+{
+	vm_offset_t		off;
+	register daddr_t	file_block;
+	daddr_t			disk_block;
+
+	if (offset % DEV_BSIZE != 0 ||
+	    size % DEV_BSIZE != 0)
+	    panic("page_read_file_direct");
+
+	if (offset >= (fdp->fd_size << fdp->fd_bshift))
+	    return (FS_NOT_IN_FILE);
+
+	off = fdir_blkoff(fdp, offset);
+	file_block = fdir_lblkno(fdp, offset);
+
+	if (file_is_device(fdp)) {
+	    disk_block = file_block;
+	} else {
+	    disk_block = fdp->fd_blocks[file_block];
+	    if (disk_block == 0)
+		return (FS_NOT_IN_FILE);
+
+	    if (size > fdp->fd_bsize) {
+	        /* Read only as much as is contiguous on disk.  */
+		daddr_t b = file_block + 1;
+		while (b < file_block + fdp->fd_size &&
+		       fdp->fd_blocks[b] == disk_block + fdir_fsbtodb(fdp, 1))
+		  ++b;
+	        size = (b - file_block) * fdp->fd_bsize;
+	    }
+	}
+
+	return (device_read(fdp->fd_dev,
+			0,
+			(recnum_t) (fdir_fsbtodb(fdp, disk_block) + btodb(off)),
+			(int) size,
+			(char **) addr,
+			size_read));
+}
+
+/*
+ * Write all or part of a data block, and
+ * return the amount written.
+ */
+int
+page_write_file_direct(fdp, offset, addr, size, size_written)
+	register struct file_direct *fdp;
+	vm_offset_t offset;
+	vm_offset_t addr;
+	vm_size_t size;
+	vm_offset_t *size_written;	/* out */
+{
+	vm_offset_t		off;
+	register daddr_t	file_block;
+	daddr_t			disk_block;
+	int			rc, num_written;
+	vm_offset_t		block_size;
+
+	if (offset % DEV_BSIZE != 0 ||
+	    size % DEV_BSIZE != 0)
+	    panic("page_write_file");
+
+	if (offset >= (fdp->fd_size << fdp->fd_bshift))
+	    return (FS_NOT_IN_FILE);
+
+	off = fdir_blkoff(fdp, offset);
+	file_block = fdir_lblkno(fdp, offset);
+
+	if (file_is_device(fdp)) {
+	    disk_block = file_block;
+	} else {
+	    disk_block = fdp->fd_blocks[file_block];
+	    if (disk_block == 0)
+		return (FS_NOT_IN_FILE);
+
+	    if (size > fdp->fd_bsize) {
+	        /* Write only as much as is contiguous on disk.  */
+		daddr_t b = file_block + 1;
+		while (b < file_block + fdp->fd_size &&
+		       fdp->fd_blocks[b] == disk_block + fdir_fsbtodb(fdp, 1))
+		  ++b;
+	        size = (b - file_block) * fdp->fd_bsize;
+	    }
+	}
+
+	/*
+	 * Write the data.  Wait for completion to keep
+	 * reads from getting ahead of writes and reading
+	 * stale data.
+	 */
+	rc = device_write(
+			fdp->fd_dev,
+			0,
+			(recnum_t) (fdir_fsbtodb(fdp, disk_block) + btodb(off)),
+			(char *) addr,
+			size,
+			&num_written);
+	*size_written = num_written;
+	return rc;
+}