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libext2fs: don't use O_DIRECT for files on tmpfs
[tools/e2fsprogs.git] / lib / ext2fs / rw_bitmaps.c
index 603b590..d80c9eb 100644 (file)
@@ -4,11 +4,12 @@
  * Copyright (C) 1993, 1994, 1994, 1996 Theodore Ts'o.
  *
  * %Begin-Header%
- * This file may be redistributed under the terms of the GNU Public
- * License.
+ * This file may be redistributed under the terms of the GNU Library
+ * General Public License, version 2.
  * %End-Header%
  */
 
+#include "config.h"
 #include <stdio.h>
 #include <string.h>
 #if HAVE_UNISTD_H
 #include "ext2fs.h"
 #include "e2image.h"
 
-#if defined(__powerpc__) && defined(EXT2FS_ENABLE_SWAPFS)
-/*
- * On the PowerPC, the big-endian variant of the ext2 filesystem
- * has its bitmaps stored as 32-bit words with bit 0 as the LSB
- * of each word.  Thus a bitmap with only bit 0 set would be, as
- * a string of bytes, 00 00 00 01 00 ...
- * To cope with this, we byte-reverse each word of a bitmap if
- * we have a big-endian filesystem, that is, if we are *not*
- * byte-swapping other word-sized numbers.
- */
-#define EXT2_BIG_ENDIAN_BITMAPS
-#endif
-
-#ifdef EXT2_BIG_ENDIAN_BITMAPS
-static void ext2fs_swap_bitmap(ext2_filsys fs, char *bitmap, int nbytes)
-{
-       __u32 *p = (__u32 *) bitmap;
-       int n;
-               
-       for (n = nbytes / sizeof(__u32); n > 0; --n, ++p)
-               *p = ext2fs_swab32(*p);
-}
-#endif
-
 static errcode_t write_bitmaps(ext2_filsys fs, int do_inode, int do_block)
 {
        dgrp_t          i;
@@ -58,33 +35,33 @@ static errcode_t write_bitmaps(ext2_filsys fs, int do_inode, int do_block)
        int             block_nbytes, inode_nbytes;
        unsigned int    nbits;
        errcode_t       retval;
-       char            *block_buf, *inode_buf;
-       int             lazy_flag = 0;
-       blk_t           blk;
-       blk_t           blk_itr = fs->super->s_first_data_block;
+       char            *block_buf = NULL, *inode_buf = NULL;
+       int             csum_flag;
+       blk64_t         blk;
+       blk64_t         blk_itr = EXT2FS_B2C(fs, fs->super->s_first_data_block);
        ext2_ino_t      ino_itr = 1;
 
        EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
 
        if (!(fs->flags & EXT2_FLAG_RW))
                return EXT2_ET_RO_FILSYS;
-       if (EXT2_HAS_COMPAT_FEATURE(fs->super, 
-                                   EXT2_FEATURE_COMPAT_LAZY_BG))
-               lazy_flag = 1;
+
+       csum_flag = ext2fs_has_group_desc_csum(fs);
+
        inode_nbytes = block_nbytes = 0;
        if (do_block) {
-               block_nbytes = EXT2_BLOCKS_PER_GROUP(fs->super) / 8;
-               retval = ext2fs_get_mem(fs->blocksize, &block_buf);
+               block_nbytes = EXT2_CLUSTERS_PER_GROUP(fs->super) / 8;
+               retval = io_channel_alloc_buf(fs->io, 0, &block_buf);
                if (retval)
-                       return retval;
+                       goto errout;
                memset(block_buf, 0xff, fs->blocksize);
        }
        if (do_inode) {
-               inode_nbytes = (size_t) 
+               inode_nbytes = (size_t)
                        ((EXT2_INODES_PER_GROUP(fs->super)+7) / 8);
-               retval = ext2fs_get_mem(fs->blocksize, &inode_buf);
+               retval = io_channel_alloc_buf(fs->io, 0, &inode_buf);
                if (retval)
-                       return retval;
+                       goto errout;
                memset(inode_buf, 0xff, fs->blocksize);
        }
 
@@ -92,36 +69,41 @@ static errcode_t write_bitmaps(ext2_filsys fs, int do_inode, int do_block)
                if (!do_block)
                        goto skip_block_bitmap;
 
-               if (lazy_flag && fs->group_desc[i].bg_flags &
-                   EXT2_BG_BLOCK_UNINIT) 
+               if (csum_flag && ext2fs_bg_flags_test(fs, i, EXT2_BG_BLOCK_UNINIT)
+                   )
                        goto skip_this_block_bitmap;
-               retval = ext2fs_get_block_bitmap_range(fs->block_map, 
+
+               retval = ext2fs_get_block_bitmap_range2(fs->block_map,
                                blk_itr, block_nbytes << 3, block_buf);
                if (retval)
-                       return retval;
+                       goto errout;
 
                if (i == fs->group_desc_count - 1) {
                        /* Force bitmap padding for the last group */
-                       nbits = ((fs->super->s_blocks_count
-                                 - fs->super->s_first_data_block)
-                                % EXT2_BLOCKS_PER_GROUP(fs->super));
+                       nbits = EXT2FS_NUM_B2C(fs,
+                               ((ext2fs_blocks_count(fs->super)
+                                 - (__u64) fs->super->s_first_data_block)
+                                % (__u64) EXT2_BLOCKS_PER_GROUP(fs->super)));
                        if (nbits)
                                for (j = nbits; j < fs->blocksize * 8; j++)
                                        ext2fs_set_bit(j, block_buf);
                }
-               blk = fs->group_desc[i].bg_block_bitmap;
+
+               retval = ext2fs_block_bitmap_csum_set(fs, i, block_buf,
+                                                     block_nbytes);
+               if (retval)
+                       return retval;
+               ext2fs_group_desc_csum_set(fs, i);
+               fs->flags |= EXT2_FLAG_DIRTY;
+
+               blk = ext2fs_block_bitmap_loc(fs, i);
                if (blk) {
-#ifdef EXT2_BIG_ENDIAN_BITMAPS
-                       if (!((fs->flags & EXT2_FLAG_SWAP_BYTES) ||
-                             (fs->flags & EXT2_FLAG_SWAP_BYTES_WRITE)))
-                               ext2fs_swap_bitmap(fs, block_buf, 
-                                                  block_nbytes);
-#endif
-                       retval = io_channel_write_blk(fs->io, blk, 1,
-                                                     block_buf);
-                       if (retval)
-                               return EXT2_ET_BLOCK_BITMAP_WRITE;
+                       retval = io_channel_write_blk64(fs->io, blk, 1,
+                                                       block_buf);
+                       if (retval) {
+                               retval = EXT2_ET_BLOCK_BITMAP_WRITE;
+                               goto errout;
+                       }
                }
        skip_this_block_bitmap:
                blk_itr += block_nbytes << 3;
@@ -130,27 +112,30 @@ static errcode_t write_bitmaps(ext2_filsys fs, int do_inode, int do_block)
                if (!do_inode)
                        continue;
 
-               if (lazy_flag && fs->group_desc[i].bg_flags &
-                   EXT2_BG_INODE_UNINIT) 
+               if (csum_flag && ext2fs_bg_flags_test(fs, i, EXT2_BG_INODE_UNINIT)
+                   )
                        goto skip_this_inode_bitmap;
-               retval = ext2fs_get_inode_bitmap_range(fs->inode_map, 
+
+               retval = ext2fs_get_inode_bitmap_range2(fs->inode_map,
                                ino_itr, inode_nbytes << 3, inode_buf);
                if (retval)
-                       return retval;
+                       goto errout;
+
+               retval = ext2fs_inode_bitmap_csum_set(fs, i, inode_buf,
+                                                     inode_nbytes);
+               if (retval)
+                       goto errout;
+               ext2fs_group_desc_csum_set(fs, i);
+               fs->flags |= EXT2_FLAG_DIRTY;
 
-               blk = fs->group_desc[i].bg_inode_bitmap;
+               blk = ext2fs_inode_bitmap_loc(fs, i);
                if (blk) {
-#ifdef EXT2_BIG_ENDIAN_BITMAPS
-                       if (!((fs->flags & EXT2_FLAG_SWAP_BYTES) ||
-                             (fs->flags & EXT2_FLAG_SWAP_BYTES_WRITE)))
-                               ext2fs_swap_bitmap(fs, inode_buf, 
-                                                  inode_nbytes);
-#endif
-                       retval = io_channel_write_blk(fs->io, blk, 1,
+                       retval = io_channel_write_blk64(fs->io, blk, 1,
                                                      inode_buf);
-                       if (retval)
-                               return EXT2_ET_INODE_BITMAP_WRITE;
+                       if (retval) {
+                               retval = EXT2_ET_INODE_BITMAP_WRITE;
+                               goto errout;
+                       }
                }
        skip_this_inode_bitmap:
                ino_itr += inode_nbytes << 3;
@@ -165,6 +150,59 @@ static errcode_t write_bitmaps(ext2_filsys fs, int do_inode, int do_block)
                ext2fs_free_mem(&inode_buf);
        }
        return 0;
+errout:
+       if (inode_buf)
+               ext2fs_free_mem(&inode_buf);
+       if (block_buf)
+               ext2fs_free_mem(&block_buf);
+       return retval;
+}
+
+static errcode_t mark_uninit_bg_group_blocks(ext2_filsys fs)
+{
+       dgrp_t                  i;
+       blk64_t                 blk;
+       ext2fs_block_bitmap     bmap = fs->block_map;
+
+       for (i = 0; i < fs->group_desc_count; i++) {
+               if (!ext2fs_bg_flags_test(fs, i, EXT2_BG_BLOCK_UNINIT))
+                       continue;
+
+               ext2fs_reserve_super_and_bgd(fs, i, bmap);
+
+               /*
+                * Mark the blocks used for the inode table
+                */
+               blk = ext2fs_inode_table_loc(fs, i);
+               if (blk)
+                       ext2fs_mark_block_bitmap_range2(bmap, blk,
+                                               fs->inode_blocks_per_group);
+
+               /*
+                * Mark block used for the block bitmap
+                */
+               blk = ext2fs_block_bitmap_loc(fs, i);
+               if (blk)
+                       ext2fs_mark_block_bitmap2(bmap, blk);
+
+               /*
+                * Mark block used for the inode bitmap
+                */
+               blk = ext2fs_inode_bitmap_loc(fs, i);
+               if (blk)
+                       ext2fs_mark_block_bitmap2(bmap, blk);
+       }
+       return 0;
+}
+
+static int bitmap_tail_verify(unsigned char *bitmap, int first, int last)
+{
+       int i;
+
+       for (i = first; i <= last; i++)
+               if (bitmap[i] != 0xff)
+                       return 0;
+       return 1;
 }
 
 static errcode_t read_bitmaps(ext2_filsys fs, int do_inode, int do_block)
@@ -173,24 +211,26 @@ static errcode_t read_bitmaps(ext2_filsys fs, int do_inode, int do_block)
        char *block_bitmap = 0, *inode_bitmap = 0;
        char *buf;
        errcode_t retval;
-       unsigned int block_nbytes = EXT2_BLOCKS_PER_GROUP(fs->super) / 8;
-       unsigned inode_nbytes = EXT2_INODES_PER_GROUP(fs->super) / 8;
-       int lazy_flag = 0;
-       int do_image = fs->flags & EXT2_FLAG_IMAGE_FILE;
+       int block_nbytes = EXT2_CLUSTERS_PER_GROUP(fs->super) / 8;
+       int inode_nbytes = EXT2_INODES_PER_GROUP(fs->super) / 8;
+       int tail_flags = 0;
+       int csum_flag;
        unsigned int    cnt;
-       blk_t   blk;
-       blk_t   blk_itr = fs->super->s_first_data_block;
-       blk_t   blk_cnt;
+       blk64_t blk;
+       blk64_t blk_itr = EXT2FS_B2C(fs, fs->super->s_first_data_block);
+       blk64_t   blk_cnt;
        ext2_ino_t ino_itr = 1;
        ext2_ino_t ino_cnt;
 
        EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
 
+       if ((block_nbytes > (int) fs->blocksize) ||
+           (inode_nbytes > (int) fs->blocksize))
+               return EXT2_ET_CORRUPT_SUPERBLOCK;
+
        fs->write_bitmaps = ext2fs_write_bitmaps;
 
-       if (EXT2_HAS_COMPAT_FEATURE(fs->super, 
-                                   EXT2_FEATURE_COMPAT_LAZY_BG))
-               lazy_flag = 1;
+       csum_flag = ext2fs_has_group_desc_csum(fs);
 
        retval = ext2fs_get_mem(strlen(fs->device_name) + 80, &buf);
        if (retval)
@@ -198,12 +238,12 @@ static errcode_t read_bitmaps(ext2_filsys fs, int do_inode, int do_block)
        if (do_block) {
                if (fs->block_map)
                        ext2fs_free_block_bitmap(fs->block_map);
-               sprintf(buf, "block bitmap for %s", fs->device_name);
+               strcpy(buf, "block bitmap for ");
+               strcat(buf, fs->device_name);
                retval = ext2fs_allocate_block_bitmap(fs, buf, &fs->block_map);
                if (retval)
                        goto cleanup;
-               retval = ext2fs_get_mem(do_image ? fs->blocksize : 
-                                       block_nbytes, &block_bitmap);
+               retval = io_channel_alloc_buf(fs->io, 0, &block_bitmap);
                if (retval)
                        goto cleanup;
        } else
@@ -211,12 +251,12 @@ static errcode_t read_bitmaps(ext2_filsys fs, int do_inode, int do_block)
        if (do_inode) {
                if (fs->inode_map)
                        ext2fs_free_inode_bitmap(fs->inode_map);
-               sprintf(buf, "inode bitmap for %s", fs->device_name);
+               strcpy(buf, "inode bitmap for ");
+               strcat(buf, fs->device_name);
                retval = ext2fs_allocate_inode_bitmap(fs, buf, &fs->inode_map);
                if (retval)
                        goto cleanup;
-               retval = ext2fs_get_mem(do_image ? fs->blocksize : 
-                                       inode_nbytes, &inode_bitmap);
+               retval = io_channel_alloc_buf(fs->io, 0, &inode_bitmap);
                if (retval)
                        goto cleanup;
        } else
@@ -224,115 +264,145 @@ static errcode_t read_bitmaps(ext2_filsys fs, int do_inode, int do_block)
        ext2fs_free_mem(&buf);
 
        if (fs->flags & EXT2_FLAG_IMAGE_FILE) {
-               blk = (fs->image_header->offset_inodemap / fs->blocksize);
+               blk = (ext2fs_le32_to_cpu(fs->image_header->offset_inodemap) / fs->blocksize);
                ino_cnt = fs->super->s_inodes_count;
-               while (inode_nbytes > 0) {
-                       retval = io_channel_read_blk(fs->image_io, blk++,
+               while (inode_bitmap && ino_cnt > 0) {
+                       retval = io_channel_read_blk64(fs->image_io, blk++,
                                                     1, inode_bitmap);
                        if (retval)
                                goto cleanup;
                        cnt = fs->blocksize << 3;
                        if (cnt > ino_cnt)
                                cnt = ino_cnt;
-                       retval = ext2fs_set_inode_bitmap_range(fs->inode_map, 
+                       retval = ext2fs_set_inode_bitmap_range2(fs->inode_map,
                                               ino_itr, cnt, inode_bitmap);
                        if (retval)
                                goto cleanup;
-                       ino_itr += fs->blocksize << 3;
-                       ino_cnt -= fs->blocksize << 3;
-                       inode_nbytes -= fs->blocksize;
+                       ino_itr += cnt;
+                       ino_cnt -= cnt;
                }
-               blk = (fs->image_header->offset_blockmap /
+               blk = (ext2fs_le32_to_cpu(fs->image_header->offset_blockmap) /
                       fs->blocksize);
-               blk_cnt = EXT2_BLOCKS_PER_GROUP(fs->super) * 
-                       fs->group_desc_count;
-               while (block_nbytes > 0) {
-                       retval = io_channel_read_blk(fs->image_io, blk++,
+               blk_cnt = EXT2_GROUPS_TO_CLUSTERS(fs->super,
+                                                 fs->group_desc_count);
+               while (block_bitmap && blk_cnt > 0) {
+                       retval = io_channel_read_blk64(fs->image_io, blk++,
                                                     1, block_bitmap);
                        if (retval)
                                goto cleanup;
                        cnt = fs->blocksize << 3;
                        if (cnt > blk_cnt)
                                cnt = blk_cnt;
-                       retval = ext2fs_set_block_bitmap_range(fs->block_map, 
+                       retval = ext2fs_set_block_bitmap_range2(fs->block_map,
                                       blk_itr, cnt, block_bitmap);
                        if (retval)
                                goto cleanup;
-                       blk_itr += fs->blocksize << 3;
-                       blk_cnt -= fs->blocksize << 3;
-                       block_nbytes -= fs->blocksize;
+                       blk_itr += cnt;
+                       blk_cnt -= cnt;
                }
                goto success_cleanup;
        }
 
        for (i = 0; i < fs->group_desc_count; i++) {
                if (block_bitmap) {
-                       blk = fs->group_desc[i].bg_block_bitmap;
-                       if (lazy_flag && fs->group_desc[i].bg_flags &
-                           EXT2_BG_BLOCK_UNINIT)
+                       blk = ext2fs_block_bitmap_loc(fs, i);
+                       if ((csum_flag &&
+                            ext2fs_bg_flags_test(fs, i, EXT2_BG_BLOCK_UNINIT) &&
+                            ext2fs_group_desc_csum_verify(fs, i)) ||
+                           (blk >= ext2fs_blocks_count(fs->super)))
                                blk = 0;
                        if (blk) {
-                               retval = io_channel_read_blk(fs->io, blk,
-                                            -block_nbytes, block_bitmap);
+                               retval = io_channel_read_blk64(fs->io, blk,
+                                                              1, block_bitmap);
                                if (retval) {
                                        retval = EXT2_ET_BLOCK_BITMAP_READ;
                                        goto cleanup;
                                }
-#ifdef EXT2_BIG_ENDIAN_BITMAPS
-                               if (!((fs->flags & EXT2_FLAG_SWAP_BYTES) ||
-                                     (fs->flags & EXT2_FLAG_SWAP_BYTES_READ)))
-                                       ext2fs_swap_bitmap(fs, block_bitmap, block_nbytes);
-#endif
+                               /* verify block bitmap checksum */
+                               if (!(fs->flags &
+                                     EXT2_FLAG_IGNORE_CSUM_ERRORS) &&
+                                   !ext2fs_block_bitmap_csum_verify(fs, i,
+                                               block_bitmap, block_nbytes)) {
+                                       retval =
+                                       EXT2_ET_BLOCK_BITMAP_CSUM_INVALID;
+                                       goto cleanup;
+                               }
+                               if (!bitmap_tail_verify((unsigned char *) block_bitmap,
+                                                       block_nbytes, fs->blocksize - 1))
+                                       tail_flags |= EXT2_FLAG_BBITMAP_TAIL_PROBLEM;
                        } else
-                               memset(block_bitmap, 0xff, block_nbytes);
+                               memset(block_bitmap, 0, block_nbytes);
                        cnt = block_nbytes << 3;
-                       retval = ext2fs_set_block_bitmap_range(fs->block_map, 
+                       retval = ext2fs_set_block_bitmap_range2(fs->block_map,
                                               blk_itr, cnt, block_bitmap);
                        if (retval)
                                goto cleanup;
                        blk_itr += block_nbytes << 3;
                }
                if (inode_bitmap) {
-                       blk = fs->group_desc[i].bg_inode_bitmap;
-                       if (lazy_flag && fs->group_desc[i].bg_flags &
-                           EXT2_BG_INODE_UNINIT)
+                       blk = ext2fs_inode_bitmap_loc(fs, i);
+                       if ((csum_flag &&
+                            ext2fs_bg_flags_test(fs, i, EXT2_BG_INODE_UNINIT) &&
+                            ext2fs_group_desc_csum_verify(fs, i)) ||
+                           (blk >= ext2fs_blocks_count(fs->super)))
                                blk = 0;
                        if (blk) {
-                               retval = io_channel_read_blk(fs->io, blk,
-                                            -inode_nbytes, inode_bitmap);
+                               retval = io_channel_read_blk64(fs->io, blk,
+                                                              1, inode_bitmap);
                                if (retval) {
                                        retval = EXT2_ET_INODE_BITMAP_READ;
                                        goto cleanup;
                                }
-#ifdef EXT2_BIG_ENDIAN_BITMAPS
-                               if (!((fs->flags & EXT2_FLAG_SWAP_BYTES) ||
-                                     (fs->flags & EXT2_FLAG_SWAP_BYTES_READ)))
-                                       ext2fs_swap_bitmap(fs, inode_bitmap, inode_nbytes);
-#endif
+
+                               /* verify inode bitmap checksum */
+                               if (!(fs->flags &
+                                     EXT2_FLAG_IGNORE_CSUM_ERRORS) &&
+                                   !ext2fs_inode_bitmap_csum_verify(fs, i,
+                                               inode_bitmap, inode_nbytes)) {
+                                       retval =
+                                       EXT2_ET_INODE_BITMAP_CSUM_INVALID;
+                                       goto cleanup;
+                               }
+                               if (!bitmap_tail_verify((unsigned char *) inode_bitmap,
+                                                       inode_nbytes, fs->blocksize - 1))
+                                       tail_flags |= EXT2_FLAG_IBITMAP_TAIL_PROBLEM;
                        } else
-                               memset(inode_bitmap, 0xff, inode_nbytes);
+                               memset(inode_bitmap, 0, inode_nbytes);
                        cnt = inode_nbytes << 3;
-                       retval = ext2fs_set_inode_bitmap_range(fs->inode_map, 
+                       retval = ext2fs_set_inode_bitmap_range2(fs->inode_map,
                                               ino_itr, cnt, inode_bitmap);
                        if (retval)
                                goto cleanup;
                        ino_itr += inode_nbytes << 3;
                }
        }
+
+       /* Mark group blocks for any BLOCK_UNINIT groups */
+       if (do_block) {
+               retval = mark_uninit_bg_group_blocks(fs);
+               if (retval)
+                       goto cleanup;
+       }
+
 success_cleanup:
-       if (inode_bitmap)
+       if (inode_bitmap) {
                ext2fs_free_mem(&inode_bitmap);
-       if (block_bitmap)
+               fs->flags &= ~EXT2_FLAG_IBITMAP_TAIL_PROBLEM;
+       }
+       if (block_bitmap) {
                ext2fs_free_mem(&block_bitmap);
+               fs->flags &= ~EXT2_FLAG_BBITMAP_TAIL_PROBLEM;
+       }
+       fs->flags |= tail_flags;
        return 0;
-       
+
 cleanup:
        if (do_block) {
-               ext2fs_free_mem(&fs->block_map);
+               ext2fs_free_block_bitmap(fs->block_map);
                fs->block_map = 0;
        }
        if (do_inode) {
-               ext2fs_free_mem(&fs->inode_map);
+               ext2fs_free_inode_bitmap(fs->inode_map);
                fs->inode_map = 0;
        }
        if (inode_bitmap)