From 794576e07585bfb31f810e25c58ee0bcfc5e19d9 Mon Sep 17 00:00:00 2001 From: Christian Brauner Date: Fri, 30 Aug 2024 15:04:51 +0200 Subject: [PATCH] ext2: store cookie in private data Store the cookie to detect concurrent seeks on directories in file->private_data. Link: https://lore.kernel.org/r/20240830-vfs-file-f_version-v1-10-6d3e4816aa7b@kernel.org Reviewed-by: Jan Kara Reviewed-by: Jeff Layton Signed-off-by: Christian Brauner --- fs/ext2/dir.c | 28 +++++++++++++++++++++++++--- 1 file changed, 25 insertions(+), 3 deletions(-) diff --git a/fs/ext2/dir.c b/fs/ext2/dir.c index 087457061c6e..6622c582f550 100644 --- a/fs/ext2/dir.c +++ b/fs/ext2/dir.c @@ -263,7 +263,7 @@ ext2_readdir(struct file *file, struct dir_context *ctx) unsigned long n = pos >> PAGE_SHIFT; unsigned long npages = dir_pages(inode); unsigned chunk_mask = ~(ext2_chunk_size(inode)-1); - bool need_revalidate = !inode_eq_iversion(inode, file->f_version); + bool need_revalidate = !inode_eq_iversion(inode, *(u64 *)file->private_data); bool has_filetype; if (pos > inode->i_size - EXT2_DIR_REC_LEN(1)) @@ -290,7 +290,7 @@ ext2_readdir(struct file *file, struct dir_context *ctx) offset = ext2_validate_entry(kaddr, offset, chunk_mask); ctx->pos = (n<f_version = inode_query_iversion(inode); + *(u64 *)file->private_data = inode_query_iversion(inode); need_revalidate = false; } de = (ext2_dirent *)(kaddr+offset); @@ -703,8 +703,30 @@ not_empty: return 0; } +static int ext2_dir_open(struct inode *inode, struct file *file) +{ + file->private_data = kzalloc(sizeof(u64), GFP_KERNEL); + if (!file->private_data) + return -ENOMEM; + return 0; +} + +static int ext2_dir_release(struct inode *inode, struct file *file) +{ + kfree(file->private_data); + return 0; +} + +static loff_t ext2_dir_llseek(struct file *file, loff_t offset, int whence) +{ + return generic_llseek_cookie(file, offset, whence, + (u64 *)file->private_data); +} + const struct file_operations ext2_dir_operations = { - .llseek = generic_file_llseek, + .open = ext2_dir_open, + .release = ext2_dir_release, + .llseek = ext2_dir_llseek, .read = generic_read_dir, .iterate_shared = ext2_readdir, .unlocked_ioctl = ext2_ioctl, -- 2.25.1