f_version is removed from struct file. Make input stop abusing f_version for stashing information for poll. Move the input state counter into input_seq_state and allocate it via seq_private_open() and free via seq_release_private(). Link: https://lore.kernel.org/r/20240830-vfs-file-f_version-v1-12-6d3e4816aa7b@xxxxxxxxxx Reviewed-by: Jan Kara <jack@xxxxxxx> Reviewed-by: Jeff Layton <jlayton@xxxxxxxxxx> Signed-off-by: Christian Brauner <brauner@xxxxxxxxxx> --- drivers/input/input.c | 47 ++++++++++++++++++++----------------------- 1 file changed, 22 insertions(+), 25 deletions(-) diff --git a/drivers/input/input.c b/drivers/input/input.c index 54c57b267b25..19ea1888da9f 100644 --- a/drivers/input/input.c +++ b/drivers/input/input.c @@ -1079,33 +1079,31 @@ static inline void input_wakeup_procfs_readers(void) wake_up(&input_devices_poll_wait); } +struct input_seq_state { + unsigned short pos; + bool mutex_acquired; + int input_devices_state; +}; + static __poll_t input_proc_devices_poll(struct file *file, poll_table *wait) { + struct seq_file *seq = file->private_data; + struct input_seq_state *state = seq->private; + poll_wait(file, &input_devices_poll_wait, wait); - if (file->f_version != input_devices_state) { - file->f_version = input_devices_state; + if (state->input_devices_state != input_devices_state) { + state->input_devices_state = input_devices_state; return EPOLLIN | EPOLLRDNORM; } return 0; } -union input_seq_state { - struct { - unsigned short pos; - bool mutex_acquired; - }; - void *p; -}; - static void *input_devices_seq_start(struct seq_file *seq, loff_t *pos) { - union input_seq_state *state = (union input_seq_state *)&seq->private; + struct input_seq_state *state = seq->private; int error; - /* We need to fit into seq->private pointer */ - BUILD_BUG_ON(sizeof(union input_seq_state) != sizeof(seq->private)); - error = mutex_lock_interruptible(&input_mutex); if (error) { state->mutex_acquired = false; @@ -1124,7 +1122,7 @@ static void *input_devices_seq_next(struct seq_file *seq, void *v, loff_t *pos) static void input_seq_stop(struct seq_file *seq, void *v) { - union input_seq_state *state = (union input_seq_state *)&seq->private; + struct input_seq_state *state = seq->private; if (state->mutex_acquired) mutex_unlock(&input_mutex); @@ -1210,7 +1208,8 @@ static const struct seq_operations input_devices_seq_ops = { static int input_proc_devices_open(struct inode *inode, struct file *file) { - return seq_open(file, &input_devices_seq_ops); + return seq_open_private(file, &input_devices_seq_ops, + sizeof(struct input_seq_state)); } static const struct proc_ops input_devices_proc_ops = { @@ -1218,17 +1217,14 @@ static const struct proc_ops input_devices_proc_ops = { .proc_poll = input_proc_devices_poll, .proc_read = seq_read, .proc_lseek = seq_lseek, - .proc_release = seq_release, + .proc_release = seq_release_private, }; static void *input_handlers_seq_start(struct seq_file *seq, loff_t *pos) { - union input_seq_state *state = (union input_seq_state *)&seq->private; + struct input_seq_state *state = seq->private; int error; - /* We need to fit into seq->private pointer */ - BUILD_BUG_ON(sizeof(union input_seq_state) != sizeof(seq->private)); - error = mutex_lock_interruptible(&input_mutex); if (error) { state->mutex_acquired = false; @@ -1243,7 +1239,7 @@ static void *input_handlers_seq_start(struct seq_file *seq, loff_t *pos) static void *input_handlers_seq_next(struct seq_file *seq, void *v, loff_t *pos) { - union input_seq_state *state = (union input_seq_state *)&seq->private; + struct input_seq_state *state = seq->private; state->pos = *pos + 1; return seq_list_next(v, &input_handler_list, pos); @@ -1252,7 +1248,7 @@ static void *input_handlers_seq_next(struct seq_file *seq, void *v, loff_t *pos) static int input_handlers_seq_show(struct seq_file *seq, void *v) { struct input_handler *handler = container_of(v, struct input_handler, node); - union input_seq_state *state = (union input_seq_state *)&seq->private; + struct input_seq_state *state = seq->private; seq_printf(seq, "N: Number=%u Name=%s", state->pos, handler->name); if (handler->filter) @@ -1273,14 +1269,15 @@ static const struct seq_operations input_handlers_seq_ops = { static int input_proc_handlers_open(struct inode *inode, struct file *file) { - return seq_open(file, &input_handlers_seq_ops); + return seq_open_private(file, &input_handlers_seq_ops, + sizeof(struct input_seq_state)); } static const struct proc_ops input_handlers_proc_ops = { .proc_open = input_proc_handlers_open, .proc_read = seq_read, .proc_lseek = seq_lseek, - .proc_release = seq_release, + .proc_release = seq_release_private, }; static int __init input_proc_init(void) -- 2.45.2 --ijrkgxanuoezdhlk--
