pidfs: remove 32bit inode number handling

Now that we have a unified inode number handling model remove the custom
ida-based allocation for 32bit.

Link: https://lore.kernel.org/r/20241129-work-pidfs-v2-2-61043d66fbce@kernel.org
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>

diff --git a/fs/pidfs.c b/fs/pidfs.c
index abfe96be9ffe3c6f4d5fb0f8acaeaa53fe2ad57a..71af820eafa5b798663789ce7758a7ffa9942aa2 100644 (file)
--- a/fs/pidfs.c
+++ b/fs/pidfs.c
@@ -391,40 +391,6 @@ struct pid *pidfd_pid(const struct file *file)
 
 static struct vfsmount *pidfs_mnt __ro_after_init;
 
-#if BITS_PER_LONG == 32
-/*
- * Provide a fallback mechanism for 32-bit systems so processes remain
- * reliably comparable by inode number even on those systems.
- */
-static DEFINE_IDA(pidfd_inum_ida);
-
-static int pidfs_inum(struct pid *pid, unsigned long *ino)
-{
-       int ret;
-
-       ret = ida_alloc_range(&pidfd_inum_ida, RESERVED_PIDS + 1,
-                             UINT_MAX, GFP_ATOMIC);
-       if (ret < 0)
-               return -ENOSPC;
-
-       *ino = ret;
-       return 0;
-}
-
-static inline void pidfs_free_inum(unsigned long ino)
-{
-       if (ino > 0)
-               ida_free(&pidfd_inum_ida, ino);
-}
-#else
-static inline int pidfs_inum(struct pid *pid, unsigned long *ino)
-{
-       *ino = pidfs_ino(pid->ino);
-       return 0;
-}
-#define pidfs_free_inum(ino) ((void)(ino))
-#endif
-
 /*
  * The vfs falls back to simple_setattr() if i_op->setattr() isn't
  * implemented. Let's reject it completely until we have a clean
@@ -476,7 +442,6 @@ static void pidfs_evict_inode(struct inode *inode)
 
        clear_inode(inode);
        put_pid(pid);
-       pidfs_free_inum(inode->i_ino);
 }
 
 static const struct super_operations pidfs_sops = {
@@ -509,13 +474,9 @@ static int pidfs_init_inode(struct inode *inode, void *data)
        inode->i_mode |= S_IRWXU;
        inode->i_op = &pidfs_inode_operations;
        inode->i_fop = &pidfs_file_operations;
+       inode->i_ino = pidfs_ino(pid->ino);
        inode->i_generation = pidfs_gen(pid->ino);
-       /*
-        * Inode numbering for pidfs start at RESERVED_PIDS + 1. This
-        * avoids collisions with the root inode which is 1 for pseudo
-        * filesystems.
-        */
-       return pidfs_inum(data, &inode->i_ino);
+       return 0;
 }
 
 static void pidfs_put_data(void *data)