NTFS: Implement support for sector sizes above 512 bytes (up to the maximum

      supported by NTFS which is 4096 bytes).

1 files changed, 99 insertions, 52 deletions

diff --git a/fs/ntfs/super.c b/fs/ntfs/super.c
index e9c0d80dfab1..489f7049146b 100644
--- a/fs/ntfs/super.c
+++ b/fs/ntfs/super.c
@@ -1,7 +1,7 @@
 /*
  * super.c - NTFS kernel super block handling. Part of the Linux-NTFS project.
  *
- * Copyright (c) 2001-2005 Anton Altaparmakov
+ * Copyright (c) 2001-2006 Anton Altaparmakov
  * Copyright (c) 2001,2002 Richard Russon
  *
  * This program/include file is free software; you can redistribute it and/or
@@ -22,6 +22,7 @@
 
 #include <linux/stddef.h>
 #include <linux/init.h>
+#include <linux/slab.h>
 #include <linux/string.h>
 #include <linux/spinlock.h>
 #include <linux/blkdev.h>       /* For bdev_hardsect_size(). */
@@ -641,7 +642,7 @@ static struct buffer_head *read_ntfs_boot_sector(struct super_block *sb,
 {
         const char *read_err_str = "Unable to read %s boot sector.";
         struct buffer_head *bh_primary, *bh_backup;
-        long nr_blocks = NTFS_SB(sb)->nr_blocks;
+        sector_t nr_blocks = NTFS_SB(sb)->nr_blocks;
 
         /* Try to read primary boot sector. */
         if ((bh_primary = sb_bread(sb, 0))) {
@@ -688,13 +689,18 @@ hotfix_primary_boot_sector:
                 /*
                  * If we managed to read sector zero and the volume is not
                  * read-only, copy the found, valid backup boot sector to the
-                 * primary boot sector.
+                 * primary boot sector.  Note we only copy the actual boot
+                 * sector structure, not the actual whole device sector as that
+                 * may be bigger and would potentially damage the $Boot system
+                 * file (FIXME: Would be nice to know if the backup boot sector
+                 * on a large sector device contains the whole boot loader or
+                 * just the first 512 bytes).
                  */
                 if (!(sb->s_flags & MS_RDONLY)) {
                         ntfs_warning(sb, "Hot-fix: Recovering invalid primary "
                                         "boot sector from backup copy.");
                         memcpy(bh_primary->b_data, bh_backup->b_data,
-                                        sb->s_blocksize);
+                                        NTFS_BLOCK_SIZE);
                         mark_buffer_dirty(bh_primary);
                         sync_dirty_buffer(bh_primary);
                         if (buffer_uptodate(bh_primary)) {
@@ -733,9 +739,13 @@ static BOOL parse_ntfs_boot_sector(ntfs_volume *vol, const NTFS_BOOT_SECTOR *b)
                         vol->sector_size);
         ntfs_debug("vol->sector_size_bits = %i (0x%x)", vol->sector_size_bits,
                         vol->sector_size_bits);
-        if (vol->sector_size != vol->sb->s_blocksize)
-                ntfs_warning(vol->sb, "The boot sector indicates a sector size "
-                                "different from the device sector size.");
+        if (vol->sector_size < vol->sb->s_blocksize) {
+                ntfs_error(vol->sb, "Sector size (%i) is smaller than the "
+                                "device block size (%lu).  This is not "
+                                "supported.  Sorry.", vol->sector_size,
+                                vol->sb->s_blocksize);
+                return FALSE;
+        }
         ntfs_debug("sectors_per_cluster = 0x%x", b->bpb.sectors_per_cluster);
         sectors_per_cluster_bits = ffs(b->bpb.sectors_per_cluster) - 1;
         ntfs_debug("sectors_per_cluster_bits = 0x%x",
@@ -748,16 +758,11 @@ static BOOL parse_ntfs_boot_sector(ntfs_volume *vol, const NTFS_BOOT_SECTOR *b)
         ntfs_debug("vol->cluster_size = %i (0x%x)", vol->cluster_size,
                         vol->cluster_size);
         ntfs_debug("vol->cluster_size_mask = 0x%x", vol->cluster_size_mask);
-        ntfs_debug("vol->cluster_size_bits = %i (0x%x)",
-                        vol->cluster_size_bits, vol->cluster_size_bits);
-        if (vol->sector_size > vol->cluster_size) {
-                ntfs_error(vol->sb, "Sector sizes above the cluster size are "
-                                "not supported.  Sorry.");
-                return FALSE;
-        }
-        if (vol->sb->s_blocksize > vol->cluster_size) {
-                ntfs_error(vol->sb, "Cluster sizes smaller than the device "
-                                "sector size are not supported.  Sorry.");
+        ntfs_debug("vol->cluster_size_bits = %i", vol->cluster_size_bits);
+        if (vol->cluster_size < vol->sector_size) {
+                ntfs_error(vol->sb, "Cluster size (%i) is smaller than the "
+                                "sector size (%i).  This is not supported.  "
+                                "Sorry.", vol->cluster_size, vol->sector_size);
                 return FALSE;
         }
         clusters_per_mft_record = b->clusters_per_mft_record;
@@ -786,11 +791,18 @@ static BOOL parse_ntfs_boot_sector(ntfs_volume *vol, const NTFS_BOOT_SECTOR *b)
          * we store $MFT/$DATA, the table of mft records in the page cache.
          */
         if (vol->mft_record_size > PAGE_CACHE_SIZE) {
-                ntfs_error(vol->sb, "Mft record size %i (0x%x) exceeds the "
-                                "page cache size on your system %lu (0x%lx).  "
+                ntfs_error(vol->sb, "Mft record size (%i) exceeds the "
+                                "PAGE_CACHE_SIZE on your system (%lu).  "
                                 "This is not supported.  Sorry.",
-                                vol->mft_record_size, vol->mft_record_size,
-                                PAGE_CACHE_SIZE, PAGE_CACHE_SIZE);
+                                vol->mft_record_size, PAGE_CACHE_SIZE);
+                return FALSE;
+        }
+        /* We cannot support mft record sizes below the sector size. */
+        if (vol->mft_record_size < vol->sector_size) {
+                ntfs_error(vol->sb, "Mft record size (%i) is smaller than the "
+                                "sector size (%i).  This is not supported.  "
+                                "Sorry.", vol->mft_record_size,
+                                vol->sector_size);
                 return FALSE;
         }
         clusters_per_index_record = b->clusters_per_index_record;
@@ -816,6 +828,14 @@ static BOOL parse_ntfs_boot_sector(ntfs_volume *vol, const NTFS_BOOT_SECTOR *b)
         ntfs_debug("vol->index_record_size_bits = %i (0x%x)",
                         vol->index_record_size_bits,
                         vol->index_record_size_bits);
+        /* We cannot support index record sizes below the sector size. */
+        if (vol->index_record_size < vol->sector_size) {
+                ntfs_error(vol->sb, "Index record size (%i) is smaller than "
+                                "the sector size (%i).  This is not "
+                                "supported.  Sorry.", vol->index_record_size,
+                                vol->sector_size);
+                return FALSE;
+        }
         /*
          * Get the size of the volume in clusters and check for 64-bit-ness.
          * Windows currently only uses 32 bits to save the clusters so we do
@@ -845,15 +865,18 @@ static BOOL parse_ntfs_boot_sector(ntfs_volume *vol, const NTFS_BOOT_SECTOR *b)
         }
         ll = sle64_to_cpu(b->mft_lcn);
         if (ll >= vol->nr_clusters) {
-                ntfs_error(vol->sb, "MFT LCN is beyond end of volume.  Weird.");
+                ntfs_error(vol->sb, "MFT LCN (%lli, 0x%llx) is beyond end of "
+                                "volume.  Weird.", (unsigned long long)ll,
+                                (unsigned long long)ll);
                 return FALSE;
         }
         vol->mft_lcn = ll;
         ntfs_debug("vol->mft_lcn = 0x%llx", (long long)vol->mft_lcn);
         ll = sle64_to_cpu(b->mftmirr_lcn);
         if (ll >= vol->nr_clusters) {
-                ntfs_error(vol->sb, "MFTMirr LCN is beyond end of volume.  "
-                                "Weird.");
+                ntfs_error(vol->sb, "MFTMirr LCN (%lli, 0x%llx) is beyond end "
+                                "of volume.  Weird.", (unsigned long long)ll,
+                                (unsigned long long)ll);
                 return FALSE;
         }
         vol->mftmirr_lcn = ll;
@@ -2685,7 +2708,7 @@ static int ntfs_fill_super(struct super_block *sb, void *opt, const int silent)
         ntfs_volume *vol;
         struct buffer_head *bh;
         struct inode *tmp_ino;
-        int result;
+        int blocksize, result;
 
         ntfs_debug("Entering.");
 #ifndef NTFS_RW
@@ -2724,60 +2747,85 @@ static int ntfs_fill_super(struct super_block *sb, void *opt, const int silent)
         if (!parse_options(vol, (char*)opt))
                 goto err_out_now;
 
+        /* We support sector sizes up to the PAGE_CACHE_SIZE. */
+        if (bdev_hardsect_size(sb->s_bdev) > PAGE_CACHE_SIZE) {
+                if (!silent)
+                        ntfs_error(sb, "Device has unsupported sector size "
+                                        "(%i).  The maximum supported sector "
+                                        "size on this architecture is %lu "
+                                        "bytes.",
+                                        bdev_hardsect_size(sb->s_bdev),
+                                        PAGE_CACHE_SIZE);
+                goto err_out_now;
+        }
         /*
-         * TODO: Fail safety check. In the future we should really be able to
-         * cope with this being the case, but for now just bail out.
+         * Setup the device access block size to NTFS_BLOCK_SIZE or the hard
+         * sector size, whichever is bigger.
          */
-        if (bdev_hardsect_size(sb->s_bdev) > NTFS_BLOCK_SIZE) {
+        blocksize = sb_min_blocksize(sb, NTFS_BLOCK_SIZE);
+        if (blocksize < NTFS_BLOCK_SIZE) {
                 if (!silent)
-                        ntfs_error(sb, "Device has unsupported hardsect_size.");
+                        ntfs_error(sb, "Unable to set device block size.");
                 goto err_out_now;
         }
-
-        /* Setup the device access block size to NTFS_BLOCK_SIZE. */
-        if (sb_set_blocksize(sb, NTFS_BLOCK_SIZE) != NTFS_BLOCK_SIZE) {
+        BUG_ON(blocksize != sb->s_blocksize);
+        ntfs_debug("Set device block size to %i bytes (block size bits %i).",
+                        blocksize, sb->s_blocksize_bits);
+        /* Determine the size of the device in units of block_size bytes. */
+        if (!i_size_read(sb->s_bdev->bd_inode)) {
                 if (!silent)
-                        ntfs_error(sb, "Unable to set block size.");
+                        ntfs_error(sb, "Unable to determine device size.");
                 goto err_out_now;
         }
-
-        /* Get the size of the device in units of NTFS_BLOCK_SIZE bytes. */
         vol->nr_blocks = i_size_read(sb->s_bdev->bd_inode) >>
-                        NTFS_BLOCK_SIZE_BITS;
-
+                        sb->s_blocksize_bits;
         /* Read the boot sector and return unlocked buffer head to it. */
         if (!(bh = read_ntfs_boot_sector(sb, silent))) {
                 if (!silent)
                         ntfs_error(sb, "Not an NTFS volume.");
                 goto err_out_now;
         }
-
         /*
-         * Extract the data from the boot sector and setup the ntfs super block
+         * Extract the data from the boot sector and setup the ntfs volume
          * using it.
          */
         result = parse_ntfs_boot_sector(vol, (NTFS_BOOT_SECTOR*)bh->b_data);
-
-        /* Initialize the cluster and mft allocators. */
-        ntfs_setup_allocators(vol);
-
         brelse(bh);
-
         if (!result) {
                 if (!silent)
                         ntfs_error(sb, "Unsupported NTFS filesystem.");
                 goto err_out_now;
         }
-
         /*
-         * TODO: When we start coping with sector sizes different from
-         * NTFS_BLOCK_SIZE, we now probably need to set the blocksize of the
-         * device (probably to NTFS_BLOCK_SIZE).
+         * If the boot sector indicates a sector size bigger than the current
+         * device block size, switch the device block size to the sector size.
+         * TODO: It may be possible to support this case even when the set
+         * below fails, we would just be breaking up the i/o for each sector
+         * into multiple blocks for i/o purposes but otherwise it should just
+         * work.  However it is safer to leave disabled until someone hits this
+         * error message and then we can get them to try it without the setting
+         * so we know for sure that it works.
          */
-
+        if (vol->sector_size > blocksize) {
+                blocksize = sb_set_blocksize(sb, vol->sector_size);
+                if (blocksize != vol->sector_size) {
+                        if (!silent)
+                                ntfs_error(sb, "Unable to set device block "
+                                                "size to sector size (%i).",
+                                                vol->sector_size);
+                        goto err_out_now;
+                }
+                BUG_ON(blocksize != sb->s_blocksize);
+                vol->nr_blocks = i_size_read(sb->s_bdev->bd_inode) >>
+                                sb->s_blocksize_bits;
+                ntfs_debug("Changed device block size to %i bytes (block size "
+                                "bits %i) to match volume sector size.",
+                                blocksize, sb->s_blocksize_bits);
+        }
+        /* Initialize the cluster and mft allocators. */
+        ntfs_setup_allocators(vol);
         /* Setup remaining fields in the super block. */
         sb->s_magic = NTFS_SB_MAGIC;
-
         /*
          * Ntfs allows 63 bits for the file size, i.e. correct would be:
          *      sb->s_maxbytes = ~0ULL >> 1;
@@ -2787,9 +2835,8 @@ static int ntfs_fill_super(struct super_block *sb, void *opt, const int silent)
          * without overflowing the index or to 2^63 - 1, whichever is smaller.
          */
         sb->s_maxbytes = MAX_LFS_FILESIZE;
-
+        /* Ntfs measures time in 100ns intervals. */
         sb->s_time_gran = 100;
-
         /*
          * Now load the metadata required for the page cache and our address
          * space operations to function. We do this by setting up a specialised