Blocks are tracked by u32, so the max permitted filesize is
U32_MAX * BLOCK_SIZE. Additionally, in order to support crypto block
sizes of 4K with a 16K block size, we must further restrict max filesize
to U32_MAX * 4096. This does not affect 4K blocksize f2fs as the natural
limits for those are well below that limit.
Signed-off-by: Daniel Rosenberg <[email protected]>
---
fs/f2fs/super.c | 9 +++++++++
1 file changed, 9 insertions(+)
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 033af907c3b1..7258a8bd6433 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -3364,6 +3364,15 @@ loff_t max_file_blocks(struct inode *inode)
leaf_count *= NIDS_PER_BLOCK;
result += leaf_count;
+ /* For compatibility with 4K crypto unit size, we must restrict
+ * the max filesize to what can fit within U32_MAX 4K units.
+ * Since the blocksize must currently be equal to the page size,
+ * we can grab that from there. inode is NULL when setting up
+ * the superblock.
+ */
+
+ result = min(result, ((loff_t) U32_MAX * 4096) >> PAGE_SHIFT);
+
return result;
}
base-commit: d346fa09abff46988de9267b67b6900d9913d5a2
--
2.43.0.rc2.451.g8631bc7472-goog
On Fri, Dec 01, 2023 at 07:03:47PM -0800, Daniel Rosenberg via Linux-f2fs-devel wrote:
> + /* For compatibility with 4K crypto unit size, we must restrict
> + * the max filesize to what can fit within U32_MAX 4K units.
> + * Since the blocksize must currently be equal to the page size,
> + * we can grab that from there. inode is NULL when setting up
> + * the superblock.
> + */
> +
> + result = min(result, ((loff_t) U32_MAX * 4096) >> PAGE_SHIFT);
This should be formatted like:
/*
* For compatibility with ...
*/
result = ...
Also, the comment should mention that this is for the IV_INO_LBLK_64 and
IV_INO_LBLK_32 encryption settings. There is no issue with the default
encryption setting.
Also, use F2FS_BLKSIZE_BITS instead of PAGE_SHIFT?
Also, the commit message could use:
Fixes: d7e9a9037de2 ("f2fs: Support Block Size == Page Size")
- Eric