To prevent direct array indexing of fs->group_desc[i] (because
the group_desc may be a different size for different filesystems)
make it an opaque pointer that may only be accessed through the
accessor functions in blknum.c. The type itself is still available
in a public header; if we have a group_desc that we know is one type
or another, it's ok to access its fields directly. This change only
prevents us from indexing off fs->group_desc[i] directly.
Change the accessors in blknum.c to use ext4fs_group_desc(), a version
of ext2fs_group_desc() which returns a ext3_group_desc pointer.
This simplifies and collapses a fair bit of code in blknum.c
Tested with "make check" but no 64-bit testing yet.
Signed-off-by: Eric Sandeen <sandeen@xxxxxxxxxx>
---
(Note, this applies after my "e2fsprogs: clean up ext2fs_bg_flags interfaces"
patch sent on 9/09/09)
diff --git a/lib/ext2fs/ext2fs.h b/lib/ext2fs/ext2fs.h
index aa4d94c..9cb67f1 100644
--- a/lib/ext2fs/ext2fs.h
+++ b/lib/ext2fs/ext2fs.h
@@ -198,6 +198,8 @@ typedef struct ext2_file *ext2_file_t;
*/
#define EXT2_MKJOURNAL_V1_SUPER 0x0000001
+struct opaque_ext2_group_desc;
+
struct struct_ext2_filsys {
errcode_t magic;
io_channel io;
@@ -208,7 +210,7 @@ struct struct_ext2_filsys {
int fragsize;
dgrp_t group_desc_count;
unsigned long desc_blocks;
- struct ext2_group_desc * group_desc;
+ struct opaque_ext2_group_desc * group_desc;
int inode_blocks_per_group;
ext2fs_inode_bitmap inode_map;
ext2fs_block_bitmap block_map;
@@ -752,7 +754,7 @@ extern void ext2fs_free_blocks_count_add(struct ext2_super_block *super,
blk64_t blk);
/* Block group descriptor accessor functions */
extern struct ext2_group_desc *ext2fs_group_desc(ext2_filsys fs,
- struct ext2_group_desc *gdp,
+ struct opaque_ext2_group_desc *gdp,
dgrp_t group);
extern blk64_t ext2fs_block_bitmap_loc(ext2_filsys fs, dgrp_t group);
extern void ext2fs_block_bitmap_loc_set(ext2_filsys fs, dgrp_t group,
diff --git a/lib/ext2fs/blknum.c b/lib/ext2fs/blknum.c
index 91abdfb..bcbfc72 100644
--- a/lib/ext2fs/blknum.c
+++ b/lib/ext2fs/blknum.c
@@ -162,7 +162,7 @@ void ext2fs_free_blocks_count_add(struct ext2_super_block *super, blk64_t blk)
* do the swap there.
*/
struct ext2_group_desc *ext2fs_group_desc(ext2_filsys fs,
- struct ext2_group_desc *gdp,
+ struct opaque_ext2_group_desc *gdp,
dgrp_t group)
{
if (fs->super->s_desc_size >= EXT2_MIN_DESC_SIZE_64BIT)
@@ -172,22 +172,26 @@ struct ext2_group_desc *ext2fs_group_desc(ext2_filsys fs,
return (struct ext2_group_desc *) gdp + group;
}
+/* Do the same but as an ext4 group desc for internal use here */
+static struct ext4_group_desc *ext4fs_group_desc(ext2_filsys fs,
+ struct opaque_ext2_group_desc *gdp,
+ dgrp_t group)
+{
+ return (struct ext4_group_desc *)ext2fs_group_desc(fs, gdp, group);
+}
+
/*
* Return the block bitmap block of a group
*/
blk64_t ext2fs_block_bitmap_loc(ext2_filsys fs, dgrp_t group)
{
- if (fs->super->s_desc_size >= EXT2_MIN_DESC_SIZE_64BIT) {
- struct ext4_group_desc *gdp;
- gdp = (struct ext4_group_desc *) (fs->group_desc) + group;
+ struct ext4_group_desc *gdp;
- return gdp->bg_block_bitmap |
- (fs->super->s_feature_incompat
- & EXT4_FEATURE_INCOMPAT_64BIT ?
- (__u64) gdp->bg_block_bitmap_hi << 32 : 0);
- }
-
- return fs->group_desc[group].bg_block_bitmap;
+ gdp = ext4fs_group_desc(fs, fs->group_desc, group);
+ return gdp->bg_block_bitmap |
+ (fs->super->s_feature_incompat
+ & EXT4_FEATURE_INCOMPAT_64BIT ?
+ (__u64)gdp->bg_block_bitmap_hi << 32 : 0);
}
/*
@@ -195,14 +199,12 @@ blk64_t ext2fs_block_bitmap_loc(ext2_filsys fs, dgrp_t group)
*/
void ext2fs_block_bitmap_loc_set(ext2_filsys fs, dgrp_t group, blk64_t blk)
{
- if (fs->super->s_desc_size >= EXT2_MIN_DESC_SIZE_64BIT) {
- struct ext4_group_desc *gdp;
- gdp = (struct ext4_group_desc *) (fs->group_desc) + group;
- gdp->bg_block_bitmap = blk;
- if (fs->super->s_feature_incompat & EXT4_FEATURE_INCOMPAT_64BIT)
- gdp->bg_block_bitmap_hi = (__u64) blk >> 32;
- } else
- fs->group_desc[group].bg_block_bitmap = blk;
+ struct ext4_group_desc *gdp;
+
+ gdp = ext4fs_group_desc(fs, fs->group_desc, group);
+ gdp->bg_block_bitmap = blk;
+ if (fs->super->s_feature_incompat & EXT4_FEATURE_INCOMPAT_64BIT)
+ gdp->bg_block_bitmap_hi = (__u64) blk >> 32;
}
/*
@@ -210,17 +212,13 @@ void ext2fs_block_bitmap_loc_set(ext2_filsys fs, dgrp_t group, blk64_t blk)
*/
blk64_t ext2fs_inode_bitmap_loc(ext2_filsys fs, dgrp_t group)
{
- if (fs->super->s_desc_size >= EXT2_MIN_DESC_SIZE_64BIT) {
- struct ext4_group_desc *gdp;
- gdp = (struct ext4_group_desc *) (fs->group_desc) + group;
-
- return gdp->bg_inode_bitmap |
- (fs->super->s_feature_incompat
- & EXT4_FEATURE_INCOMPAT_64BIT ?
- (__u64) gdp->bg_inode_bitmap_hi << 32 : 0);
- }
+ struct ext4_group_desc *gdp;
- return fs->group_desc[group].bg_inode_bitmap;
+ gdp = ext4fs_group_desc(fs, fs->group_desc, group);
+ return gdp->bg_inode_bitmap |
+ (fs->super->s_feature_incompat
+ & EXT4_FEATURE_INCOMPAT_64BIT ?
+ (__u64) gdp->bg_inode_bitmap_hi << 32 : 0);
}
/*
@@ -228,14 +226,12 @@ blk64_t ext2fs_inode_bitmap_loc(ext2_filsys fs, dgrp_t group)
*/
void ext2fs_inode_bitmap_loc_set(ext2_filsys fs, dgrp_t group, blk64_t blk)
{
- if (fs->super->s_desc_size >= EXT2_MIN_DESC_SIZE_64BIT) {
- struct ext4_group_desc *gdp;
- gdp = (struct ext4_group_desc *) (fs->group_desc) + group;
- gdp->bg_inode_bitmap = blk;
- if (fs->super->s_feature_incompat & EXT4_FEATURE_INCOMPAT_64BIT)
- gdp->bg_inode_bitmap_hi = (__u64) blk >> 32;
- } else
- fs->group_desc[group].bg_inode_bitmap = blk;
+ struct ext4_group_desc *gdp;
+
+ gdp = ext4fs_group_desc(fs, fs->group_desc, group);
+ gdp->bg_inode_bitmap = blk;
+ if (fs->super->s_feature_incompat & EXT4_FEATURE_INCOMPAT_64BIT)
+ gdp->bg_inode_bitmap_hi = (__u64) blk >> 32;
}
/*
@@ -243,17 +239,13 @@ void ext2fs_inode_bitmap_loc_set(ext2_filsys fs, dgrp_t group, blk64_t blk)
*/
blk64_t ext2fs_inode_table_loc(ext2_filsys fs, dgrp_t group)
{
- if (fs->super->s_desc_size >= EXT2_MIN_DESC_SIZE_64BIT) {
- struct ext4_group_desc *gdp;
- gdp = (struct ext4_group_desc *) (fs->group_desc) + group;
-
- return gdp->bg_inode_table |
- (fs->super->s_feature_incompat
- & EXT4_FEATURE_INCOMPAT_64BIT ?
- (__u64) gdp->bg_inode_table_hi << 32 : 0);
- }
+ struct ext4_group_desc *gdp;
- return fs->group_desc[group].bg_inode_table;
+ gdp = ext4fs_group_desc(fs, fs->group_desc, group);
+ return gdp->bg_inode_table |
+ (fs->super->s_feature_incompat
+ & EXT4_FEATURE_INCOMPAT_64BIT ?
+ (__u64) gdp->bg_inode_table_hi << 32 : 0);
}
/*
@@ -261,14 +253,12 @@ blk64_t ext2fs_inode_table_loc(ext2_filsys fs, dgrp_t group)
*/
void ext2fs_inode_table_loc_set(ext2_filsys fs, dgrp_t group, blk64_t blk)
{
- if (fs->super->s_desc_size >= EXT2_MIN_DESC_SIZE_64BIT) {
- struct ext4_group_desc *gdp;
- gdp = (struct ext4_group_desc *) (fs->group_desc) + group;
- gdp->bg_inode_table = blk;
- if (fs->super->s_feature_incompat & EXT4_FEATURE_INCOMPAT_64BIT)
- gdp->bg_inode_table_hi = (__u64) blk >> 32;
- } else
- fs->group_desc[group].bg_inode_table = blk;
+ struct ext4_group_desc *gdp;
+
+ gdp = ext4fs_group_desc(fs, fs->group_desc, group);
+ gdp->bg_inode_table = blk;
+ if (fs->super->s_feature_incompat & EXT4_FEATURE_INCOMPAT_64BIT)
+ gdp->bg_inode_table_hi = (__u64) blk >> 32;
}
/*
@@ -276,17 +266,13 @@ void ext2fs_inode_table_loc_set(ext2_filsys fs, dgrp_t group, blk64_t blk)
*/
__u32 ext2fs_bg_free_blocks_count(ext2_filsys fs, dgrp_t group)
{
- if (fs->super->s_desc_size >= EXT2_MIN_DESC_SIZE_64BIT) {
- struct ext4_group_desc *gdp;
- gdp = (struct ext4_group_desc *) (fs->group_desc) + group;
+ struct ext4_group_desc *gdp;
- return gdp->bg_free_blocks_count |
- (fs->super->s_feature_incompat
- & EXT4_FEATURE_INCOMPAT_64BIT ?
- (__u32) gdp->bg_free_blocks_count_hi << 16 : 0);
- }
-
- return fs->group_desc[group].bg_free_blocks_count;
+ gdp = ext4fs_group_desc(fs, fs->group_desc, group);
+ return gdp->bg_free_blocks_count |
+ (fs->super->s_feature_incompat
+ & EXT4_FEATURE_INCOMPAT_64BIT ?
+ (__u32) gdp->bg_free_blocks_count_hi << 16 : 0);
}
/*
@@ -294,14 +280,13 @@ __u32 ext2fs_bg_free_blocks_count(ext2_filsys fs, dgrp_t group)
*/
void ext2fs_bg_free_blocks_count_set(ext2_filsys fs, dgrp_t group, __u32 n)
{
- if (fs->super->s_desc_size >= EXT2_MIN_DESC_SIZE_64BIT) {
- struct ext4_group_desc *gdp;
- gdp = (struct ext4_group_desc *) (fs->group_desc) + group;
- gdp->bg_free_blocks_count = n;
- if (fs->super->s_feature_incompat & EXT4_FEATURE_INCOMPAT_64BIT)
- gdp->bg_free_blocks_count_hi = (__u32) n >> 16;
- } else
- fs->group_desc[group].bg_free_blocks_count = n;
+ struct ext4_group_desc *gdp;
+
+ gdp = ext4fs_group_desc(fs, fs->group_desc, group);
+ gdp->bg_free_blocks_count = n;
+
+ if (fs->super->s_feature_incompat & EXT4_FEATURE_INCOMPAT_64BIT)
+ gdp->bg_free_blocks_count_hi = (__u32) n >> 16;
}
/*
@@ -309,17 +294,13 @@ void ext2fs_bg_free_blocks_count_set(ext2_filsys fs, dgrp_t group, __u32 n)
*/
__u32 ext2fs_bg_free_inodes_count(ext2_filsys fs, dgrp_t group)
{
- if (fs->super->s_desc_size >= EXT2_MIN_DESC_SIZE_64BIT) {
- struct ext4_group_desc *gdp;
- gdp = (struct ext4_group_desc *) (fs->group_desc) + group;
+ struct ext4_group_desc *gdp;
- return gdp->bg_free_inodes_count |
- (fs->super->s_feature_incompat
- & EXT4_FEATURE_INCOMPAT_64BIT ?
- (__u32) gdp->bg_free_inodes_count_hi << 16 : 0);
- }
-
- return fs->group_desc[group].bg_free_inodes_count;
+ gdp = ext4fs_group_desc(fs, fs->group_desc, group);
+ return gdp->bg_free_inodes_count |
+ (fs->super->s_feature_incompat
+ & EXT4_FEATURE_INCOMPAT_64BIT ?
+ (__u32) gdp->bg_free_inodes_count_hi << 16 : 0);
}
/*
@@ -327,14 +308,12 @@ __u32 ext2fs_bg_free_inodes_count(ext2_filsys fs, dgrp_t group)
*/
void ext2fs_bg_free_inodes_count_set(ext2_filsys fs, dgrp_t group, __u32 n)
{
- if (fs->super->s_desc_size >= EXT2_MIN_DESC_SIZE_64BIT) {
- struct ext4_group_desc *gdp;
- gdp = (struct ext4_group_desc *) (fs->group_desc) + group;
- gdp->bg_free_inodes_count = n;
- if (fs->super->s_feature_incompat & EXT4_FEATURE_INCOMPAT_64BIT)
- gdp->bg_free_inodes_count_hi = (__u32) n >> 16;
- } else
- fs->group_desc[group].bg_free_inodes_count = n;
+ struct ext4_group_desc *gdp;
+
+ gdp = ext4fs_group_desc(fs, fs->group_desc, group);
+ gdp->bg_free_inodes_count = n;
+ if (fs->super->s_feature_incompat & EXT4_FEATURE_INCOMPAT_64BIT)
+ gdp->bg_free_inodes_count_hi = (__u32) n >> 16;
}
/*
@@ -342,17 +321,13 @@ void ext2fs_bg_free_inodes_count_set(ext2_filsys fs, dgrp_t group, __u32 n)
*/
__u32 ext2fs_bg_used_dirs_count(ext2_filsys fs, dgrp_t group)
{
- if (fs->super->s_desc_size >= EXT2_MIN_DESC_SIZE_64BIT) {
- struct ext4_group_desc *gdp;
- gdp = (struct ext4_group_desc *) (fs->group_desc) + group;
-
- return gdp->bg_used_dirs_count |
- (fs->super->s_feature_incompat
- & EXT4_FEATURE_INCOMPAT_64BIT ?
- (__u32) gdp->bg_used_dirs_count_hi << 16 : 0);
- }
+ struct ext4_group_desc *gdp;
- return fs->group_desc[group].bg_used_dirs_count;
+ gdp = ext4fs_group_desc(fs, fs->group_desc, group);
+ return gdp->bg_used_dirs_count |
+ (fs->super->s_feature_incompat
+ & EXT4_FEATURE_INCOMPAT_64BIT ?
+ (__u32) gdp->bg_used_dirs_count_hi << 16 : 0);
}
/*
@@ -360,14 +335,12 @@ __u32 ext2fs_bg_used_dirs_count(ext2_filsys fs, dgrp_t group)
*/
void ext2fs_bg_used_dirs_count_set(ext2_filsys fs, dgrp_t group, __u32 n)
{
- if (fs->super->s_desc_size >= EXT2_MIN_DESC_SIZE_64BIT) {
- struct ext4_group_desc *gdp;
- gdp = (struct ext4_group_desc *) (fs->group_desc) + group;
- gdp->bg_used_dirs_count = n;
- if (fs->super->s_feature_incompat & EXT4_FEATURE_INCOMPAT_64BIT)
- gdp->bg_used_dirs_count_hi = (__u32) n >> 16;
- } else
- fs->group_desc[group].bg_used_dirs_count = n;
+ struct ext4_group_desc *gdp;
+
+ gdp = ext4fs_group_desc(fs, fs->group_desc, group);
+ gdp->bg_used_dirs_count = n;
+ if (fs->super->s_feature_incompat & EXT4_FEATURE_INCOMPAT_64BIT)
+ gdp->bg_used_dirs_count_hi = (__u32) n >> 16;
}
/*
@@ -375,17 +348,13 @@ void ext2fs_bg_used_dirs_count_set(ext2_filsys fs, dgrp_t group, __u32 n)
*/
__u32 ext2fs_bg_itable_unused(ext2_filsys fs, dgrp_t group)
{
- if (fs->super->s_desc_size >= EXT2_MIN_DESC_SIZE_64BIT) {
- struct ext4_group_desc *gdp;
- gdp = (struct ext4_group_desc *) (fs->group_desc) + group;
-
- return gdp->bg_itable_unused |
- (fs->super->s_feature_incompat
- & EXT4_FEATURE_INCOMPAT_64BIT ?
- (__u32) gdp->bg_itable_unused_hi << 16 : 0);
- }
+ struct ext4_group_desc *gdp;
- return fs->group_desc[group].bg_itable_unused;
+ gdp = ext4fs_group_desc(fs, fs->group_desc, group);
+ return gdp->bg_itable_unused |
+ (fs->super->s_feature_incompat
+ & EXT4_FEATURE_INCOMPAT_64BIT ?
+ (__u32) gdp->bg_itable_unused_hi << 16 : 0);
}
/*
@@ -393,14 +362,12 @@ __u32 ext2fs_bg_itable_unused(ext2_filsys fs, dgrp_t group)
*/
void ext2fs_bg_itable_unused_set(ext2_filsys fs, dgrp_t group, __u32 n)
{
- if (fs->super->s_desc_size >= EXT2_MIN_DESC_SIZE_64BIT) {
- struct ext4_group_desc *gdp;
- gdp = (struct ext4_group_desc *) (fs->group_desc) + group;
- gdp->bg_itable_unused = n;
- if (fs->super->s_feature_incompat & EXT4_FEATURE_INCOMPAT_64BIT)
- gdp->bg_itable_unused_hi = (__u32) n >> 16;
- } else
- fs->group_desc[group].bg_itable_unused = n;
+ struct ext4_group_desc *gdp;
+
+ gdp = ext4fs_group_desc(fs, fs->group_desc, group);
+ gdp->bg_itable_unused = n;
+ if (fs->super->s_feature_incompat & EXT4_FEATURE_INCOMPAT_64BIT)
+ gdp->bg_itable_unused_hi = (__u32) n >> 16;
}
/*
@@ -408,14 +375,10 @@ void ext2fs_bg_itable_unused_set(ext2_filsys fs, dgrp_t group, __u32 n)
*/
__u16 ext2fs_bg_flags(ext2_filsys fs, dgrp_t group)
{
- if (fs->super->s_desc_size >= EXT2_MIN_DESC_SIZE_64BIT) {
- struct ext4_group_desc *gdp;
- gdp = (struct ext4_group_desc *) (fs->group_desc) + group;
+ struct ext4_group_desc *gdp;
- return gdp->bg_flags;
- }
-
- return fs->group_desc[group].bg_flags;
+ gdp = ext4fs_group_desc(fs, fs->group_desc, group);
+ return gdp->bg_flags;
}
/*
@@ -423,15 +386,11 @@ __u16 ext2fs_bg_flags(ext2_filsys fs, dgrp_t group)
*/
void ext2fs_bg_flags_zap(ext2_filsys fs, dgrp_t group)
{
- if (fs->super->s_desc_size >= EXT2_MIN_DESC_SIZE_64BIT) {
- struct ext4_group_desc *gdp;
- gdp = (struct ext4_group_desc *) (fs->group_desc) + group;
-
- gdp->bg_flags = 0;
- return;
- }
+ struct ext4_group_desc *gdp;
- fs->group_desc[group].bg_flags = 0;
+ gdp = ext4fs_group_desc(fs, fs->group_desc, group);
+ gdp->bg_flags = 0;
+ return;
}
/*
@@ -439,14 +398,10 @@ void ext2fs_bg_flags_zap(ext2_filsys fs, dgrp_t group)
*/
int ext2fs_bg_flag_test(ext2_filsys fs, dgrp_t group, __u16 bg_flag)
{
- if (fs->super->s_desc_size >= EXT2_MIN_DESC_SIZE_64BIT) {
- struct ext4_group_desc *gdp;
- gdp = (struct ext4_group_desc *) (fs->group_desc) + group;
-
- return gdp->bg_flags & bg_flag;
- }
+ struct ext4_group_desc *gdp;
- return fs->group_desc[group].bg_flags & bg_flag;
+ gdp = ext4fs_group_desc(fs, fs->group_desc, group);
+ return gdp->bg_flags & bg_flag;
}
/*
@@ -454,15 +409,11 @@ int ext2fs_bg_flag_test(ext2_filsys fs, dgrp_t group, __u16 bg_flag)
*/
void ext2fs_bg_flags_set(ext2_filsys fs, dgrp_t group, __u16 bg_flags)
{
- if (fs->super->s_desc_size >= EXT2_MIN_DESC_SIZE_64BIT) {
- struct ext4_group_desc *gdp;
- gdp = (struct ext4_group_desc *) (fs->group_desc) + group;
+ struct ext4_group_desc *gdp;
- gdp->bg_flags |= bg_flags;
- return;
- }
-
- fs->group_desc[group].bg_flags |= bg_flags;
+ gdp = ext4fs_group_desc(fs, fs->group_desc, group);
+ gdp->bg_flags |= bg_flags;
+ return;
}
/*
@@ -470,15 +421,11 @@ void ext2fs_bg_flags_set(ext2_filsys fs, dgrp_t group, __u16 bg_flags)
*/
void ext2fs_bg_flags_clear(ext2_filsys fs, dgrp_t group, __u16 bg_flags)
{
- if (fs->super->s_desc_size >= EXT2_MIN_DESC_SIZE_64BIT) {
- struct ext4_group_desc *gdp;
- gdp = (struct ext4_group_desc *) (fs->group_desc) + group;
-
- gdp->bg_flags &= ~bg_flags;
- return;
- }
+ struct ext4_group_desc *gdp;
- fs->group_desc[group].bg_flags &= ~bg_flags;
+ gdp = ext4fs_group_desc(fs, fs->group_desc, group);
+ gdp->bg_flags &= ~bg_flags;
+ return;
}
/*
@@ -486,14 +433,10 @@ void ext2fs_bg_flags_clear(ext2_filsys fs, dgrp_t group, __u16 bg_flags)
*/
__u16 ext2fs_bg_checksum(ext2_filsys fs, dgrp_t group)
{
- if (fs->super->s_desc_size >= EXT2_MIN_DESC_SIZE_64BIT) {
- struct ext4_group_desc *gdp;
- gdp = (struct ext4_group_desc *) (fs->group_desc) + group;
-
- return gdp->bg_checksum;
- }
+ struct ext4_group_desc *gdp;
- return fs->group_desc[group].bg_checksum;
+ gdp = ext4fs_group_desc(fs, fs->group_desc, group);
+ return gdp->bg_checksum;
}
/*
@@ -501,15 +444,11 @@ __u16 ext2fs_bg_checksum(ext2_filsys fs, dgrp_t group)
*/
void ext2fs_bg_checksum_set(ext2_filsys fs, dgrp_t group, __u16 checksum)
{
- if (fs->super->s_desc_size >= EXT2_MIN_DESC_SIZE_64BIT) {
- struct ext4_group_desc *gdp;
- gdp = (struct ext4_group_desc *) (fs->group_desc) + group;
-
- gdp->bg_checksum = checksum;
- return;
- }
+ struct ext4_group_desc *gdp;
- fs->group_desc[group].bg_checksum = checksum;
+ gdp = ext4fs_group_desc(fs, fs->group_desc, group);
+ gdp->bg_checksum = checksum;
+ return;
}
/*
--
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