Merge tag 'vfs-7.0-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull misc vfs updates from Christian Brauner:
 "This contains a mix of VFS cleanups, performance improvements, API
  fixes, documentation, and a deprecation notice.

  Scalability and performance:

   - Rework pid allocation to only take pidmap_lock once instead of
     twice during alloc_pid(), improving thread creation/teardown
     throughput by 10-16% depending on false-sharing luck. Pad the
     namespace refcount to reduce false-sharing

   - Track file lock presence via a flag in ->i_opflags instead of
     reading ->i_flctx, avoiding false-sharing with ->i_readcount on
     open/close hot paths. Measured 4-16% improvement on 24-core
     open-in-a-loop benchmarks

   - Use a consume fence in locks_inode_context() to match the
     store-release/load-consume idiom, eliminating a hardware fence on
     some architectures

   - Annotate cdev_lock with __cacheline_aligned_in_smp to prevent
     false-sharing

   - Remove a redundant DCACHE_MANAGED_DENTRY check in
     __follow_mount_rcu() that never fires since the caller already
     verifies it, eliminating a 100% mispredicted branch

   - Fix a 100% mispredicted likely() in devcgroup_inode_permission()
     that became wrong after a prior code reorder

  Bug fixes and correctness:

   - Make insert_inode_locked() wait for inode destruction instead of
     skipping, fixing a corner case where two matching inodes could
     exist in the hash

   - Move f_mode initialization before file_ref_init() in alloc_file()
     to respect the SLAB_TYPESAFE_BY_RCU ordering contract

   - Add a WARN_ON_ONCE guard in try_to_free_buffers() for folios with
     no buffers attached, preventing a null pointer dereference when
     AS_RELEASE_ALWAYS is set but no release_folio op exists

   - Fix select restart_block to store end_time as timespec64, avoiding
     truncation of tv_sec on 32-bit architectures

   - Make dump_inode() use get_kernel_nofault() to safely access inode
     and superblock fields, matching the dump_mapping() pattern

  API modernization:

   - Make posix_acl_to_xattr() allocate the buffer internally since
     every single caller was doing it anyway. Reduces boilerplate and
     unnecessary error checking across ~15 filesystems

   - Replace deprecated simple_strtoul() with kstrtoul() for the
     ihash_entries, dhash_entries, mhash_entries, and mphash_entries
     boot parameters, adding proper error handling

   - Convert chardev code to use guard(mutex) and __free(kfree) cleanup
     patterns

   - Replace min_t() with min() or umin() in VFS code to avoid silently
     truncating unsigned long to unsigned int

   - Gate LOOKUP_RCU assertions behind CONFIG_DEBUG_VFS since callers
     already check the flag

  Deprecation:

   - Begin deprecating legacy BSD process accounting (acct(2)). The
     interface has numerous footguns and better alternatives exist
     (eBPF)

  Documentation:

   - Fix and complete kernel-doc for struct export_operations, removing
     duplicated documentation between ReST and source

   - Fix kernel-doc warnings for __start_dirop() and ilookup5_nowait()

  Testing:

   - Add a kunit test for initramfs cpio handling of entries with
     filesize > PATH_MAX

  Misc:

   - Add missing <linux/init_task.h> include in fs_struct.c"

* tag 'vfs-7.0-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (28 commits)
  posix_acl: make posix_acl_to_xattr() alloc the buffer
  fs: make insert_inode_locked() wait for inode destruction
  initramfs_test: kunit test for cpio.filesize > PATH_MAX
  fs: improve dump_inode() to safely access inode fields
  fs: add <linux/init_task.h> for 'init_fs'
  docs: exportfs: Use source code struct documentation
  fs: move initializing f_mode before file_ref_init()
  exportfs: Complete kernel-doc for struct export_operations
  exportfs: Mark struct export_operations functions at kernel-doc
  exportfs: Fix kernel-doc output for get_name()
  acct(2): begin the deprecation of legacy BSD process accounting
  device_cgroup: remove branch hint after code refactor
  VFS: fix __start_dirop() kernel-doc warnings
  fs: Describe @isnew parameter in ilookup5_nowait()
  fs/namei: Remove redundant DCACHE_MANAGED_DENTRY check in __follow_mount_rcu
  fs: only assert on LOOKUP_RCU when built with CONFIG_DEBUG_VFS
  select: store end_time as timespec64 in restart block
  chardev: Switch to guard(mutex) and __free(kfree)
  namespace: Replace simple_strtoul with kstrtoul to parse boot params
  dcache: Replace simple_strtoul with kstrtoul in set_dhash_entries
  ...

3 files changed, 8 insertions, 14 deletions

diff --git a/fs/fuse/acl.c b/fs/fuse/acl.c
index 8f484b105f13..cbde6ac1add3 100644
--- a/fs/fuse/acl.c
+++ b/fs/fuse/acl.c
@@ -122,20 +122,16 @@ int fuse_set_acl(struct mnt_idmap *idmap, struct dentry *dentry,
 		 * them to be refreshed the next time they are used,
 		 * and it also updates i_ctime.
 		 */
-		size_t size = posix_acl_xattr_size(acl->a_count);
+		size_t size;
 		void *value;
 
-		if (size > PAGE_SIZE)
-			return -E2BIG;
-
-		value = kmalloc(size, GFP_KERNEL);
+		value = posix_acl_to_xattr(fc->user_ns, acl, &size, GFP_KERNEL);
 		if (!value)
 			return -ENOMEM;
 
-		ret = posix_acl_to_xattr(fc->user_ns, acl, value, size);
-		if (ret < 0) {
+		if (size > PAGE_SIZE) {
 			kfree(value);
-			return ret;
+			return -E2BIG;
 		}
 
 		/*
diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
index 6d59cbc877c6..a30c8b57d478 100644
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -1813,7 +1813,7 @@ static int fuse_notify_store(struct fuse_conn *fc, unsigned int size,
 			goto out_iput;
 
 		folio_offset = ((index - folio->index) << PAGE_SHIFT) + offset;
-		nr_bytes = min_t(unsigned, num, folio_size(folio) - folio_offset);
+		nr_bytes = min(num, folio_size(folio) - folio_offset);
 		nr_pages = (offset + nr_bytes + PAGE_SIZE - 1) >> PAGE_SHIFT;
 
 		err = fuse_copy_folio(cs, &folio, folio_offset, nr_bytes, 0);
diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index 78fa46cfc636..dffd454e30e2 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -1323,10 +1323,8 @@ static ssize_t fuse_fill_write_pages(struct fuse_io_args *ia,
 static inline unsigned int fuse_wr_pages(loff_t pos, size_t len,
 				     unsigned int max_pages)
 {
-	return min_t(unsigned int,
-		     ((pos + len - 1) >> PAGE_SHIFT) -
-		     (pos >> PAGE_SHIFT) + 1,
-		     max_pages);
+	return min(((pos + len - 1) >> PAGE_SHIFT) - (pos >> PAGE_SHIFT) + 1,
+		   max_pages);
 }
 
 static ssize_t fuse_perform_write(struct kiocb *iocb, struct iov_iter *ii)
@@ -1607,7 +1605,7 @@ static int fuse_get_user_pages(struct fuse_args_pages *ap, struct iov_iter *ii,
 			struct folio *folio = page_folio(pages[i]);
 			unsigned int offset = start +
 				(folio_page_idx(folio, pages[i]) << PAGE_SHIFT);
-			unsigned int len = min_t(unsigned int, ret, PAGE_SIZE - start);
+			unsigned int len = umin(ret, PAGE_SIZE - start);
 
 			ap->descs[ap->num_folios].offset = offset;
 			ap->descs[ap->num_folios].length = len;