[RFC PATCH v6.6 02/10] libfs: Define a minimum directory offset

cel
2025-01-24T19:19:58Z

[ Upstream commit 7beea725a8ca412c6190090ce7c3a13b169592a1 ]

This value is used in several places, so make it a symbolic
constant.

Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Link: https://lore.kernel.org/r/170820142741.6328.12428356024575347885.stgit@91.116.238.104.host.secureserver.net
Signed-off-by: Christian Brauner <brauner@kernel.org>
Stable-dep-of: ecba88a3b32d ("libfs: Add simple_offset_empty()")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
fs/libfs.c | 13 ++++++++-----
1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/fs/libfs.c b/fs/libfs.c
index 430f7c95336c..c3dc58e776f9 100644
--- a/fs/libfs.c
+++ b/fs/libfs.c
@@ -239,6 +239,11 @@ const struct inode_operations simple_dir_inode_operations = {
};
EXPORT_SYMBOL(simple_dir_inode_operations);

+/* 0 is '.', 1 is '..', so always start with offset 2 or more */
+enum {
+ DIR_OFFSET_MIN = 2,
+};
+
static void offset_set(struct dentry *dentry, u32 offset)
{
dentry->d_fsdata = (void *)((uintptr_t)(offset));
@@ -260,9 +265,7 @@ void simple_offset_init(struct offset_ctx *octx)
{
xa_init_flags(&octx->xa, XA_FLAGS_ALLOC1);
lockdep_set_class(&octx->xa.xa_lock, &simple_offset_xa_lock);
-
- /* 0 is '.', 1 is '..', so always start with offset 2 */
- octx->next_offset = 2;
+ octx->next_offset = DIR_OFFSET_MIN;
}

/**
@@ -275,7 +278,7 @@ void simple_offset_init(struct offset_ctx *octx)
*/
int simple_offset_add(struct offset_ctx *octx, struct dentry *dentry)
{
- static const struct xa_limit limit = XA_LIMIT(2, U32_MAX);
+ static const struct xa_limit limit = XA_LIMIT(DIR_OFFSET_MIN, U32_MAX);
u32 offset;
int ret;

@@ -480,7 +483,7 @@ static int offset_readdir(struct file *file, struct dir_context *ctx)
return 0;

/* In this case, ->private_data is protected by f_pos_lock */
- if (ctx->pos == 2)
+ if (ctx->pos == DIR_OFFSET_MIN)
file->private_data = NULL;
else if (file->private_data == ERR_PTR(-ENOENT))
return 0;
--
2.47.0