2008-06-12 Pavel Roskin <proski@gnu.org>

* fs/fshelp.c (grub_fshelp_read): New function.  Implement
	linear disk read with journal translation.
	* fs/ext2.c: Use grub_fshelp_read() instead of grub_disk_read().
	* include/grub/fshelp.h: Declare grub_fshelp_read().

ChangeLog

@@ -1,3 +1,10 @@
+2008-06-12  Pavel Roskin  <proski@gnu.org>
+
+	* fs/fshelp.c (grub_fshelp_read): New function.  Implement
+	linear disk read with journal translation.
+	* fs/ext2.c: Use grub_fshelp_read() instead of grub_disk_read().
+	* include/grub/fshelp.h: Declare grub_fshelp_read().
+
 2008-06-09  Pavel Roskin  <proski@gnu.org>
 
 	* fs/minix.c (grub_minix_mount): Handle error reading

fs/ext2.c

@@ -257,12 +257,11 @@ inline static grub_err_t
 grub_ext2_blockgroup (struct grub_ext2_data *data, int group, 
 		      struct grub_ext2_block_group *blkgrp)
 {
-  return grub_disk_read (data->disk,
+  return grub_fshelp_read (data->disk, data->journal,
-			 (grub_fshelp_map_block (data->journal,
+			   grub_le_to_cpu32 (data->sblock.first_data_block) + 1,
-                                                 grub_le_to_cpu32 (data->sblock.first_data_block) + 1)
+			   group * sizeof (struct grub_ext2_block_group),
-			  << LOG2_EXT2_BLOCK_SIZE (data)),
+			   sizeof (struct grub_ext2_block_group),
-			 group * sizeof (struct grub_ext2_block_group), 
+			   (char *) blkgrp, LOG2_EXT2_BLOCK_SIZE (data));
-			 sizeof (struct grub_ext2_block_group), (char *) blkgrp);
 }
 
 
@@ -283,11 +282,9 @@ grub_ext2_read_block (grub_fshelp_node_t node, grub_disk_addr_t fileblock)
     {
       grub_uint32_t indir[blksz / 4];
 
-      if (grub_disk_read (data->disk, 
+      if (grub_fshelp_read (data->disk, data->journal,
-			  grub_fshelp_map_block(data->journal,
+			    grub_le_to_cpu32 (inode->blocks.indir_block),
-                                                grub_le_to_cpu32 (inode->blocks.indir_block))
+			    0, blksz, (char *) indir, log2_blksz))
-			  << log2_blksz,
-			  0, blksz, (char *) indir))
 	return grub_errno;
 	  
       blknr = grub_le_to_cpu32 (indir[fileblock - INDIRECT_BLOCKS]);
@@ -300,18 +297,14 @@ grub_ext2_read_block (grub_fshelp_node_t node, grub_disk_addr_t fileblock)
 					 + blksz / 4);
       grub_uint32_t indir[blksz / 4];
 
-      if (grub_disk_read (data->disk, 
+      if (grub_fshelp_read (data->disk, data->journal,
-			  grub_fshelp_map_block(data->journal,
+			    grub_le_to_cpu32 (inode->blocks.double_indir_block),
-                                                grub_le_to_cpu32 (inode->blocks.double_indir_block))
+			    0, blksz, (char *) indir, log2_blksz))
-			  << log2_blksz,
-			  0, blksz, (char *) indir))
 	return grub_errno;
 
-      if (grub_disk_read (data->disk,
+      if (grub_fshelp_read (data->disk, data->journal,
-			  grub_fshelp_map_block(data->journal,
+			    grub_le_to_cpu32 (indir[rblock / perblock]),
-                                                grub_le_to_cpu32 (indir[rblock / perblock]))
+			    0, blksz, (char *) indir, log2_blksz))
-			  << log2_blksz,
-			  0, blksz, (char *) indir))
 	return grub_errno;
 
       
@@ -372,12 +365,11 @@ grub_ext2_read_inode (struct grub_ext2_data *data,
     % inodes_per_block;
   
   /* Read the inode.  */
-  if (grub_disk_read (data->disk, 
+  if (grub_fshelp_read (data->disk, data->journal,
-		      grub_fshelp_map_block(data->journal,
+			grub_le_to_cpu32 (blkgrp.inode_table_id) + blkno,
-                                            grub_le_to_cpu32 (blkgrp.inode_table_id) + blkno)
+			EXT2_INODE_SIZE (data) * blkoff,
-                      << LOG2_EXT2_BLOCK_SIZE (data),
+			sizeof (struct grub_ext2_inode), (char *) inode,
-		      EXT2_INODE_SIZE (data) * blkoff,
+			LOG2_EXT2_BLOCK_SIZE (data)))
-		      sizeof (struct grub_ext2_inode), (char *) inode))
     return grub_errno;
   
   return 0;

fs/fshelp.c

@@ -215,6 +215,45 @@ grub_fshelp_find_file (const char *path, grub_fshelp_node_t rootnode,
 }
 
 
+/* Read LEN bytes from the block BLOCK on disk DISK into the buffer BUF,
+   beginning with the block POS.  Apply mappings from LOG.  The blocks
+   have a size of LOG2BLOCKSIZE (in log2).  */
+grub_err_t grub_fshelp_read (grub_disk_t disk, grub_fshelp_journal_t log,
+			     grub_disk_addr_t block, grub_off_t pos,
+			     grub_size_t len, char *buf, int log2blocksize)
+{
+  grub_off_t relblk;
+
+  relblk = pos >> (log2blocksize + GRUB_DISK_SECTOR_BITS);
+  block += relblk;
+  pos -= relblk << (log2blocksize + GRUB_DISK_SECTOR_BITS);
+
+  while (len > 0)
+    {
+      grub_err_t ret;
+      grub_size_t size;
+
+      size = (GRUB_DISK_SECTOR_SIZE << log2blocksize) - pos;
+      if (size > len)
+	size = len;
+
+      ret = grub_disk_read (disk,
+			    grub_fshelp_map_block (log, block) << log2blocksize,
+			    pos, size, buf);
+
+      if (ret)
+	return ret;
+
+      block++;
+      pos = 0;
+      buf += size;
+      len -= size;
+    }
+
+  return 0;
+}
+
+
 /* Read LEN bytes from the file NODE on disk DISK into the buffer BUF,
    beginning with the block POS.  READ_HOOK should be set before
    reading a block from the file.  GET_BLOCK is used to translate file

include/grub/fshelp.h

@@ -84,6 +84,15 @@ EXPORT_FUNC(grub_fshelp_find_file) (const char *path,
 				    enum grub_fshelp_filetype expect);
 
 
+/* Read LEN bytes from the block BLOCK on disk DISK into the buffer BUF,
+   beginning with the block POS.  Apply mappings from LOG.  The blocks
+   have a size of LOG2BLOCKSIZE (in log2).  */
+grub_err_t
+EXPORT_FUNC(grub_fshelp_read) (grub_disk_t disk, grub_fshelp_journal_t log,
+			       grub_disk_addr_t block, grub_off_t pos,
+			       grub_size_t len, char *buf, int log2blocksize);
+
+
 /* Read LEN bytes from the file NODE on disk DISK into the buffer BUF,
    beginning with the block POS.  READ_HOOK should be set before
    reading a block from the file.  GET_BLOCK is used to translate file