[PATCH v3 0/2] vfs: follow-on fixes for i_ino widening

[PATCH v3 0/2] vfs: follow-on fixes for i_ino widening

[Jeff Layton]

Just some patches to fix follow-on issues reported after the
inode->i_ino widening series. Christian, could you toss these
onto the vfs-7.1.kino branch?

Signed-off-by: Jeff Layton <jlayton@kernel.org>
---
Changes in v3:
- nilfs2: find index with bitwise & operation instead of div_u64_rem()
- add compile-time assertion that NILFS_BMAP_GROUP_DIV is power of two
- Link to v2: https://lore.kernel.org/r/20260313-iino-u64-v2-0-f9abda2464d5@kernel.org

Changes in v2:
- rename variable in nilfs2 patch from "rem" to "index"
- reword comment and commit log for better accuracy in EVM patch

---
Jeff Layton (2):
      EVM: add comment describing why ino field is still unsigned long
      nilfs2: fix 64-bit division operations in nilfs_bmap_find_target_in_group()

 fs/nilfs2/bmap.c                    | 15 +++++++++++----
 security/integrity/evm/evm_crypto.c |  6 ++++++
 2 files changed, 17 insertions(+), 4 deletions(-)
---
base-commit: 9840bb66e7e5dffd72b03201318f154a10b06b4a
change-id: 20260310-iino-u64-424fa570d850

Best regards,
-- 
Jeff Layton <jlayton@kernel.org>

[PATCH v3 1/2] EVM: add comment describing why ino field is still unsigned long

[Jeff Layton]

Mimi pointed out that we didn't widen the inode number field in struct
h_misc alongside the inode->i_ino widening. While we could make an
equivalent change there, that would require EVM resigning on all 32-bit
hosts.

Instead, leave the field as an unsigned long. This should have no effect
on 64-bit hosts, and allow things to continue working on 32-bit hosts in
the cases where the i_ino fits in 32-bits.

Add a comment explaining why it's being left as unsigned long.

Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
---
 security/integrity/evm/evm_crypto.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/security/integrity/evm/evm_crypto.c b/security/integrity/evm/evm_crypto.c
index c0ca4eedb0fe5d5c30f45f515a4bc90248ec64ea..1c41af2f91a60a714878ff93b554c90e45546503 100644
--- a/security/integrity/evm/evm_crypto.c
+++ b/security/integrity/evm/evm_crypto.c
@@ -144,6 +144,12 @@ static void hmac_add_misc(struct shash_desc *desc, struct inode *inode,
 			  char type, char *digest)
 {
 	struct h_misc {
+		/*
+		 * Although inode->i_ino is now u64, this field remains
+		 * unsigned long to allow existing HMAC and signatures from
+		 * 32-bit hosts to continue working when i_ino hasn't changed
+		 * and fits in a u32.
+		 */
 		unsigned long ino;
 		__u32 generation;
 		uid_t uid;

-- 
2.53.0

[PATCH v3 2/2] nilfs2: fix 64-bit division operations in nilfs_bmap_find_target_in_group()

[Jeff Layton]

With the change to make inode->i_ino a u64, the build started failing on
32-bit ARM with:

    ERROR: modpost: "__aeabi_uldivmod" [fs/nilfs2/nilfs2.ko] undefined!

Fix this by using udiv_u64() for the division.

For finding the index into the group, switch to using a bitwise &
operation since that's more efficient. With this change however,
NILFS_BMAP_GROUP_DIV must be a power of two, so add a compile-time
assertion for that.

Fixes: 998a59d371c2 ("treewide: fix missed i_ino format specifier conversions")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202603100602.KPxiClIO-lkp@intel.com/
Reviewed-by: Viacheslav Dubeyko <slava@dubeyko.com>
Acked-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
---
 fs/nilfs2/bmap.c | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/fs/nilfs2/bmap.c b/fs/nilfs2/bmap.c
index 824f2bd91c167965ec3a660202b6e6c5f1fe007e..5f0f1f283af0208e1879e2e84b0b5b9629fd6b8a 100644
--- a/fs/nilfs2/bmap.c
+++ b/fs/nilfs2/bmap.c
@@ -450,18 +450,25 @@ __u64 nilfs_bmap_find_target_seq(const struct nilfs_bmap *bmap, __u64 key)
 		return NILFS_BMAP_INVALID_PTR;
 }
 
-#define NILFS_BMAP_GROUP_DIV	8
+#define NILFS_BMAP_GROUP_DIV	8	/* must be power of 2 */
+
 __u64 nilfs_bmap_find_target_in_group(const struct nilfs_bmap *bmap)
 {
 	struct inode *dat = nilfs_bmap_get_dat(bmap);
 	unsigned long entries_per_group = nilfs_palloc_entries_per_group(dat);
-	unsigned long group = bmap->b_inode->i_ino / entries_per_group;
+	unsigned long group;
+	u32 index;
+
+	BUILD_BUG_ON_NOT_POWER_OF_2(NILFS_BMAP_GROUP_DIV);
+
+	group = div_u64(bmap->b_inode->i_ino, entries_per_group);
+	index = bmap->b_inode->i_ino & (NILFS_BMAP_GROUP_DIV - 1);
 
 	return group * entries_per_group +
-		(bmap->b_inode->i_ino % NILFS_BMAP_GROUP_DIV) *
-		(entries_per_group / NILFS_BMAP_GROUP_DIV);
+	       index * (entries_per_group / NILFS_BMAP_GROUP_DIV);
 }
 
+
 static struct lock_class_key nilfs_bmap_dat_lock_key;
 static struct lock_class_key nilfs_bmap_mdt_lock_key;
 

-- 
2.53.0

Re: [PATCH v3 0/2] vfs: follow-on fixes for i_ino widening

[Christian Brauner]

On Mon, 16 Mar 2026 15:02:21 -0400, Jeff Layton wrote:
> Just some patches to fix follow-on issues reported after the
> inode->i_ino widening series. Christian, could you toss these
> onto the vfs-7.1.kino branch?

Applied to the vfs-7.1.kino branch of the vfs/vfs.git tree.
Patches in the vfs-7.1.kino branch should appear in linux-next soon.

Please report any outstanding bugs that were missed during review in a
new review to the original patch series allowing us to drop it.

It's encouraged to provide Acked-bys and Reviewed-bys even though the
patch has now been applied. If possible patch trailers will be updated.

Note that commit hashes shown below are subject to change due to rebase,
trailer updates or similar. If in doubt, please check the listed branch.

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs.git
branch: vfs-7.1.kino

[1/2] EVM: add comment describing why ino field is still unsigned long
      https://git.kernel.org/vfs/vfs/c/bef5b11087ce
[2/2] nilfs2: fix 64-bit division operations in nilfs_bmap_find_target_in_group()
      https://git.kernel.org/vfs/vfs/c/81359c146fba