From: Eric Biggers Date: Sun, 10 Aug 2025 07:57:05 +0000 (-0700) Subject: fs: remove inode::i_verity_info X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=818c659ac164e4e4639ceaedaccbdfebb1ef63b5;p=users%2Fhch%2Fmisc.git fs: remove inode::i_verity_info Now that all fsverity-capable filesystems store the pointer to fsverity_info in the filesystem-specific part of the inode structure, inode::i_verity_info is no longer needed. Update fsverity_info_addr() to no longer support the fallback to inode::i_verity_info. Finally, remove inode::i_verity_info itself, and move the forward declaration of struct fsverity_info from fs.h (which no longer needs it) to fsverity.h. The end result of the migration to the filesystem-specific pointer is memory savings on CONFIG_FS_VERITY=y kernels for all filesystems that don't support fsverity. Specifically, their in-memory inodes are now smaller by the size of a pointer: either 4 or 8 bytes. Co-developed-by: Christian Brauner Signed-off-by: Eric Biggers Link: https://lore.kernel.org/20250810075706.172910-13-ebiggers@kernel.org Signed-off-by: Christian Brauner --- diff --git a/include/linux/fs.h b/include/linux/fs.h index 1dafa18169be..12ecc6b0e6f9 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -73,7 +73,6 @@ struct seq_file; struct workqueue_struct; struct iov_iter; struct fscrypt_operations; -struct fsverity_info; struct fsverity_operations; struct fsnotify_mark_connector; struct fsnotify_sb_info; @@ -779,10 +778,6 @@ struct inode { struct fsnotify_mark_connector __rcu *i_fsnotify_marks; #endif -#ifdef CONFIG_FS_VERITY - struct fsverity_info *i_verity_info; -#endif - void *i_private; /* fs or device private pointer */ } __randomize_layout; diff --git a/include/linux/fsverity.h b/include/linux/fsverity.h index e0f132cb7839..844f7b8b56bb 100644 --- a/include/linux/fsverity.h +++ b/include/linux/fsverity.h @@ -26,6 +26,8 @@ /* Arbitrary limit to bound the kmalloc() size. Can be changed. */ #define FS_VERITY_MAX_DESCRIPTOR_SIZE 16384 +struct fsverity_info; + /* Verity operations for filesystems */ struct fsverity_operations { /** @@ -130,11 +132,15 @@ struct fsverity_operations { #ifdef CONFIG_FS_VERITY +/* + * Returns the address of the verity info pointer within the filesystem-specific + * part of the inode. (To save memory on filesystems that don't support + * fsverity, a field in 'struct inode' itself is no longer used.) + */ static inline struct fsverity_info ** fsverity_info_addr(const struct inode *inode) { - if (inode->i_sb->s_vop->inode_info_offs == 0) - return (struct fsverity_info **)&inode->i_verity_info; + VFS_WARN_ON_ONCE(inode->i_sb->s_vop->inode_info_offs == 0); return (void *)inode + inode->i_sb->s_vop->inode_info_offs; }