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-rw-r--r--fs/minix/bitmap.c18
-rw-r--r--fs/minix/inode.c25
-rw-r--r--fs/minix/minix.h9
3 files changed, 42 insertions, 10 deletions
diff --git a/fs/minix/bitmap.c b/fs/minix/bitmap.c
index 3f32bcb..7c82c29 100644
--- a/fs/minix/bitmap.c
+++ b/fs/minix/bitmap.c
@@ -20,10 +20,11 @@ static const int nibblemap[] = { 4,3,3,2,3,2,2,1,3,2,2,1,2,1,1,0 };
static DEFINE_SPINLOCK(bitmap_lock);
-static unsigned long count_free(struct buffer_head *map[], unsigned numblocks, __u32 numbits)
+static unsigned long count_free(struct buffer_head *map[], unsigned blocksize, __u32 numbits)
{
unsigned i, j, sum = 0;
struct buffer_head *bh;
+ unsigned numblocks = minix_blocks_needed(numbits, blocksize);
for (i=0; i<numblocks-1; i++) {
if (!(bh=map[i]))
@@ -105,10 +106,12 @@ int minix_new_block(struct inode * inode)
return 0;
}
-unsigned long minix_count_free_blocks(struct minix_sb_info *sbi)
+unsigned long minix_count_free_blocks(struct super_block *sb)
{
- return (count_free(sbi->s_zmap, sbi->s_zmap_blocks,
- sbi->s_nzones - sbi->s_firstdatazone + 1)
+ struct minix_sb_info *sbi = minix_sb(sb);
+ u32 bits = sbi->s_nzones - (sbi->s_firstdatazone + 1);
+
+ return (count_free(sbi->s_zmap, sb->s_blocksize, bits)
<< sbi->s_log_zone_size);
}
@@ -273,7 +276,10 @@ struct inode *minix_new_inode(const struct inode *dir, int mode, int *error)
return inode;
}
-unsigned long minix_count_free_inodes(struct minix_sb_info *sbi)
+unsigned long minix_count_free_inodes(struct super_block *sb)
{
- return count_free(sbi->s_imap, sbi->s_imap_blocks, sbi->s_ninodes + 1);
+ struct minix_sb_info *sbi = minix_sb(sb);
+ u32 bits = sbi->s_ninodes + 1;
+
+ return count_free(sbi->s_imap, sb->s_blocksize, bits);
}
diff --git a/fs/minix/inode.c b/fs/minix/inode.c
index 64cdcd6..1d9e339 100644
--- a/fs/minix/inode.c
+++ b/fs/minix/inode.c
@@ -279,6 +279,27 @@ static int minix_fill_super(struct super_block *s, void *data, int silent)
else if (sbi->s_mount_state & MINIX_ERROR_FS)
printk("MINIX-fs: mounting file system with errors, "
"running fsck is recommended\n");
+
+ /* Apparently minix can create filesystems that allocate more blocks for
+ * the bitmaps than needed. We simply ignore that, but verify it didn't
+ * create one with not enough blocks and bail out if so.
+ */
+ block = minix_blocks_needed(sbi->s_ninodes, s->s_blocksize);
+ if (sbi->s_imap_blocks < block) {
+ printk("MINIX-fs: file system does not have enough "
+ "imap blocks allocated. Refusing to mount\n");
+ goto out_iput;
+ }
+
+ block = minix_blocks_needed(
+ (sbi->s_nzones - (sbi->s_firstdatazone + 1)),
+ s->s_blocksize);
+ if (sbi->s_zmap_blocks < block) {
+ printk("MINIX-fs: file system does not have enough "
+ "zmap blocks allocated. Refusing to mount.\n");
+ goto out_iput;
+ }
+
return 0;
out_iput:
@@ -339,10 +360,10 @@ static int minix_statfs(struct dentry *dentry, struct kstatfs *buf)
buf->f_type = sb->s_magic;
buf->f_bsize = sb->s_blocksize;
buf->f_blocks = (sbi->s_nzones - sbi->s_firstdatazone) << sbi->s_log_zone_size;
- buf->f_bfree = minix_count_free_blocks(sbi);
+ buf->f_bfree = minix_count_free_blocks(sb);
buf->f_bavail = buf->f_bfree;
buf->f_files = sbi->s_ninodes;
- buf->f_ffree = minix_count_free_inodes(sbi);
+ buf->f_ffree = minix_count_free_inodes(sb);
buf->f_namelen = sbi->s_namelen;
buf->f_fsid.val[0] = (u32)id;
buf->f_fsid.val[1] = (u32)(id >> 32);
diff --git a/fs/minix/minix.h b/fs/minix/minix.h
index 341e212..6415fe0 100644
--- a/fs/minix/minix.h
+++ b/fs/minix/minix.h
@@ -48,10 +48,10 @@ extern struct minix_inode * minix_V1_raw_inode(struct super_block *, ino_t, stru
extern struct minix2_inode * minix_V2_raw_inode(struct super_block *, ino_t, struct buffer_head **);
extern struct inode * minix_new_inode(const struct inode *, int, int *);
extern void minix_free_inode(struct inode * inode);
-extern unsigned long minix_count_free_inodes(struct minix_sb_info *sbi);
+extern unsigned long minix_count_free_inodes(struct super_block *sb);
extern int minix_new_block(struct inode * inode);
extern void minix_free_block(struct inode *inode, unsigned long block);
-extern unsigned long minix_count_free_blocks(struct minix_sb_info *sbi);
+extern unsigned long minix_count_free_blocks(struct super_block *sb);
extern int minix_getattr(struct vfsmount *, struct dentry *, struct kstat *);
extern int minix_prepare_chunk(struct page *page, loff_t pos, unsigned len);
@@ -88,6 +88,11 @@ static inline struct minix_inode_info *minix_i(struct inode *inode)
return list_entry(inode, struct minix_inode_info, vfs_inode);
}
+static inline unsigned minix_blocks_needed(unsigned bits, unsigned blocksize)
+{
+ return DIV_ROUND_UP(bits, blocksize * 8);
+}
+
#if defined(CONFIG_MINIX_FS_NATIVE_ENDIAN) && \
defined(CONFIG_MINIX_FS_BIG_ENDIAN_16BIT_INDEXED)
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