libfs.c has many functions that are useful to implement dentry and inode operations, but not many at the filesystem level. As a result, code to create files and inodes has a lot of duplication, to the point that tracefs has copied several hundred lines from debugfs. The main two libfs.c functions for filesystems are simple_pin_fs and simple_release_fs, which hide a somewhat complicated locking sequence that is needed to serialize vfs_kern_mount and mntget. In this series, my aim is to add functions that create dentries and inodes of various kinds (either anonymous inodes, or directory/file/symlink). These functions take the code that was duplicated across debugfs and tracefs and move it to libfs.c. In order to limit the number of arguments to the new functions, the series first creates a data type that is passed to both simple_pin_fs/simple_release_fs and the new creation functions. The new struct, introduced in patch 2, simply groups the "mount" and "count" arguments to simple_pin_fs and simple_release_fs. Patches 1-4 are preparations to introduce the new simple_fs struct and new functions that are useful in the remainder of the series. Patch 5 introduces the dentry and inode creation functions. Patch 6-7 can then adopt them in debugfs and tracefs. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@xxxxxxxxxx> v1->v2: rename simple_new_inode in new_inode_current_time, more detailed explanations, put all common code in fs/libfs.c v2->v3: remove unused debugfs_get_inode and tracefs_get_inode functions Emanuele Giuseppe Esposito (7): apparmor: just use vfs_kern_mount to make .null libfs: wrap simple_pin_fs/simple_release_fs arguments in a struct libfs: introduce new_inode_current_time libfs: add alloc_anon_inode wrapper libfs: add file creation functions debugfs: switch to simplefs inode creation API tracefs: switch to simplefs inode creation API drivers/gpu/drm/drm_drv.c | 11 +- drivers/misc/cxl/api.c | 13 +- drivers/scsi/cxlflash/ocxl_hw.c | 14 +- fs/binfmt_misc.c | 9 +- fs/configfs/mount.c | 10 +- fs/debugfs/inode.c | 169 +++--------------- fs/libfs.c | 299 ++++++++++++++++++++++++++++++-- fs/tracefs/inode.c | 106 ++--------- include/linux/fs.h | 31 +++- security/apparmor/apparmorfs.c | 38 ++-- security/inode.c | 11 +- 11 files changed, 399 insertions(+), 312 deletions(-) -- 2.25.2
