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authorLinus Torvalds <torvalds@linux-foundation.org>2024-01-08 10:26:08 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2024-01-08 10:26:08 -0800
commitc604110e662a54568073a03176402b624e740310 (patch)
tree3121f7a3e57d9cff898029245ad94048a655c792 /fs/eventfd.c
parent1ab33c03145d0f6c345823fc2da935d9a1a9e9fc (diff)
parentdd8f87f21dc3da2eaf46e7401173f935b90b13a8 (diff)
Merge tag 'vfs-6.8.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull misc vfs updates from Christian Brauner: "This contains the usual miscellaneous features, cleanups, and fixes for vfs and individual fses. Features: - Add Jan Kara as VFS reviewer - Show correct device and inode numbers in proc/<pid>/maps for vma files on stacked filesystems. This is now easily doable thanks to the backing file work from the last cycles. This comes with selftests Cleanups: - Remove a redundant might_sleep() from wait_on_inode() - Initialize pointer with NULL, not 0 - Clarify comment on access_override_creds() - Rework and simplify eventfd_signal() and eventfd_signal_mask() helpers - Process aio completions in batches to avoid needless wakeups - Completely decouple struct mnt_idmap from namespaces. We now only keep the actual idmapping around and don't stash references to namespaces - Reformat maintainer entries to indicate that a given subsystem belongs to fs/ - Simplify fput() for files that were never opened - Get rid of various pointless file helpers - Rename various file helpers - Rename struct file members after SLAB_TYPESAFE_BY_RCU switch from last cycle - Make relatime_need_update() return bool - Use GFP_KERNEL instead of GFP_USER when allocating superblocks - Replace deprecated ida_simple_*() calls with their current ida_*() counterparts Fixes: - Fix comments on user namespace id mapping helpers. They aren't kernel doc comments so they shouldn't be using /** - s/Retuns/Returns/g in various places - Add missing parameter documentation on can_move_mount_beneath() - Rename i_mapping->private_data to i_mapping->i_private_data - Fix a false-positive lockdep warning in pipe_write() for watch queues - Improve __fget_files_rcu() code generation to improve performance - Only notify writer that pipe resizing has finished after setting pipe->max_usage otherwise writers are never notified that the pipe has been resized and hang - Fix some kernel docs in hfsplus - s/passs/pass/g in various places - Fix kernel docs in ntfs - Fix kcalloc() arguments order reported by gcc 14 - Fix uninitialized value in reiserfs" * tag 'vfs-6.8.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (36 commits) reiserfs: fix uninit-value in comp_keys watch_queue: fix kcalloc() arguments order ntfs: dir.c: fix kernel-doc function parameter warnings fs: fix doc comment typo fs tree wide selftests/overlayfs: verify device and inode numbers in /proc/pid/maps fs/proc: show correct device and inode numbers in /proc/pid/maps eventfd: Remove usage of the deprecated ida_simple_xx() API fs: super: use GFP_KERNEL instead of GFP_USER for super block allocation fs/hfsplus: wrapper.c: fix kernel-doc warnings fs: add Jan Kara as reviewer fs/inode: Make relatime_need_update return bool pipe: wakeup wr_wait after setting max_usage file: remove __receive_fd() file: stop exposing receive_fd_user() fs: replace f_rcuhead with f_task_work file: remove pointless wrapper file: s/close_fd_get_file()/file_close_fd()/g Improve __fget_files_rcu() code generation (and thus __fget_light()) file: massage cleanup of files that failed to open fs/pipe: Fix lockdep false-positive in watchqueue pipe_write() ...
Diffstat (limited to 'fs/eventfd.c')
-rw-r--r--fs/eventfd.c46
1 files changed, 17 insertions, 29 deletions
diff --git a/fs/eventfd.c b/fs/eventfd.c
index 33a918f9566c..ad8186d47ba7 100644
--- a/fs/eventfd.c
+++ b/fs/eventfd.c
@@ -43,7 +43,17 @@ struct eventfd_ctx {
int id;
};
-__u64 eventfd_signal_mask(struct eventfd_ctx *ctx, __u64 n, __poll_t mask)
+/**
+ * eventfd_signal_mask - Increment the event counter
+ * @ctx: [in] Pointer to the eventfd context.
+ * @mask: [in] poll mask
+ *
+ * This function is supposed to be called by the kernel in paths that do not
+ * allow sleeping. In this function we allow the counter to reach the ULLONG_MAX
+ * value, and we signal this as overflow condition by returning a EPOLLERR
+ * to poll(2).
+ */
+void eventfd_signal_mask(struct eventfd_ctx *ctx, __poll_t mask)
{
unsigned long flags;
@@ -56,45 +66,23 @@ __u64 eventfd_signal_mask(struct eventfd_ctx *ctx, __u64 n, __poll_t mask)
* safe context.
*/
if (WARN_ON_ONCE(current->in_eventfd))
- return 0;
+ return;
spin_lock_irqsave(&ctx->wqh.lock, flags);
current->in_eventfd = 1;
- if (ULLONG_MAX - ctx->count < n)
- n = ULLONG_MAX - ctx->count;
- ctx->count += n;
+ if (ctx->count < ULLONG_MAX)
+ ctx->count++;
if (waitqueue_active(&ctx->wqh))
wake_up_locked_poll(&ctx->wqh, EPOLLIN | mask);
current->in_eventfd = 0;
spin_unlock_irqrestore(&ctx->wqh.lock, flags);
-
- return n;
-}
-
-/**
- * eventfd_signal - Adds @n to the eventfd counter.
- * @ctx: [in] Pointer to the eventfd context.
- * @n: [in] Value of the counter to be added to the eventfd internal counter.
- * The value cannot be negative.
- *
- * This function is supposed to be called by the kernel in paths that do not
- * allow sleeping. In this function we allow the counter to reach the ULLONG_MAX
- * value, and we signal this as overflow condition by returning a EPOLLERR
- * to poll(2).
- *
- * Returns the amount by which the counter was incremented. This will be less
- * than @n if the counter has overflowed.
- */
-__u64 eventfd_signal(struct eventfd_ctx *ctx, __u64 n)
-{
- return eventfd_signal_mask(ctx, n, 0);
}
-EXPORT_SYMBOL_GPL(eventfd_signal);
+EXPORT_SYMBOL_GPL(eventfd_signal_mask);
static void eventfd_free_ctx(struct eventfd_ctx *ctx)
{
if (ctx->id >= 0)
- ida_simple_remove(&eventfd_ida, ctx->id);
+ ida_free(&eventfd_ida, ctx->id);
kfree(ctx);
}
@@ -407,7 +395,7 @@ static int do_eventfd(unsigned int count, int flags)
init_waitqueue_head(&ctx->wqh);
ctx->count = count;
ctx->flags = flags;
- ctx->id = ida_simple_get(&eventfd_ida, 0, 0, GFP_KERNEL);
+ ctx->id = ida_alloc(&eventfd_ida, GFP_KERNEL);
flags &= EFD_SHARED_FCNTL_FLAGS;
flags |= O_RDWR;