summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2011-11-21 12:10:47 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2011-11-21 12:10:47 -0800
commit7758c4d6e9371efa04a1cf1b124bbf9cc43e830e (patch)
tree415cfe6bd68bc5df544b48f16c789e1f4b9165bd
parentcc11f9edd919002d8b3a03601a181a449150defd (diff)
parentdd179946db2493646955efc112d73c85b3cafcb1 (diff)
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: VFS: Log the fact that we've given ELOOP rather than creating a loop minixfs: kill manual hweight(), simplify fs/minix: Verify bitmap block counts before mounting
-rw-r--r--fs/dcache.c11
-rw-r--r--fs/minix/bitmap.c55
-rw-r--r--fs/minix/inode.c25
-rw-r--r--fs/minix/minix.h11
4 files changed, 65 insertions, 37 deletions
diff --git a/fs/dcache.c b/fs/dcache.c
index a901c6901bce..10ba92def3f6 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -36,6 +36,7 @@
#include <linux/bit_spinlock.h>
#include <linux/rculist_bl.h>
#include <linux/prefetch.h>
+#include <linux/ratelimit.h>
#include "internal.h"
/*
@@ -2383,8 +2384,16 @@ struct dentry *d_materialise_unique(struct dentry *dentry, struct inode *inode)
actual = __d_unalias(inode, dentry, alias);
}
write_sequnlock(&rename_lock);
- if (IS_ERR(actual))
+ if (IS_ERR(actual)) {
+ if (PTR_ERR(actual) == -ELOOP)
+ pr_warn_ratelimited(
+ "VFS: Lookup of '%s' in %s %s"
+ " would have caused loop\n",
+ dentry->d_name.name,
+ inode->i_sb->s_type->name,
+ inode->i_sb->s_id);
dput(alias);
+ }
goto out_nolock;
}
}
diff --git a/fs/minix/bitmap.c b/fs/minix/bitmap.c
index 3f32bcb0d9bd..ef175cb8cfd8 100644
--- a/fs/minix/bitmap.c
+++ b/fs/minix/bitmap.c
@@ -16,38 +16,26 @@
#include <linux/bitops.h>
#include <linux/sched.h>
-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)
+/*
+ * bitmap consists of blocks filled with 16bit words
+ * bit set == busy, bit clear == free
+ * endianness is a mess, but for counting zero bits it really doesn't matter...
+ */
+static __u32 count_free(struct buffer_head *map[], unsigned blocksize, __u32 numbits)
{
- unsigned i, j, sum = 0;
- struct buffer_head *bh;
-
- for (i=0; i<numblocks-1; i++) {
- if (!(bh=map[i]))
- return(0);
- for (j=0; j<bh->b_size; j++)
- sum += nibblemap[bh->b_data[j] & 0xf]
- + nibblemap[(bh->b_data[j]>>4) & 0xf];
- }
+ __u32 sum = 0;
+ unsigned blocks = DIV_ROUND_UP(numbits, blocksize * 8);
- if (numblocks==0 || !(bh=map[numblocks-1]))
- return(0);
- i = ((numbits - (numblocks-1) * bh->b_size * 8) / 16) * 2;
- for (j=0; j<i; j++) {
- sum += nibblemap[bh->b_data[j] & 0xf]
- + nibblemap[(bh->b_data[j]>>4) & 0xf];
+ while (blocks--) {
+ unsigned words = blocksize / 2;
+ __u16 *p = (__u16 *)(*map++)->b_data;
+ while (words--)
+ sum += 16 - hweight16(*p++);
}
- i = numbits%16;
- if (i!=0) {
- i = *(__u16 *)(&bh->b_data[j]) | ~((1<<i) - 1);
- sum += nibblemap[i & 0xf] + nibblemap[(i>>4) & 0xf];
- sum += nibblemap[(i>>8) & 0xf] + nibblemap[(i>>12) & 0xf];
- }
- return(sum);
+ return sum;
}
void minix_free_block(struct inode *inode, unsigned long block)
@@ -105,10 +93,12 @@ 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 +263,10 @@ 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 64cdcd662ffc..1d9e33966db0 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 341e2122879a..26bbd55e82ea 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)
@@ -125,7 +130,7 @@ static inline int minix_find_first_zero_bit(const void *vaddr, unsigned size)
if (!size)
return 0;
- size = (size >> 4) + ((size & 15) > 0);
+ size >>= 4;
while (*p++ == 0xffff) {
if (--size == 0)
return (p - addr) << 4;