From 3d03295a7e9194c2318977b44999972ce3609664 Mon Sep 17 00:00:00 2001 From: Jani Nikula Date: Tue, 15 Dec 2020 20:45:47 -0800 Subject: relay: remove unused buf_mapped and buf_unmapped callbacks Patch series "relay: cleanup and const callbacks", v2. None of the relay users require the use of mutable structs for callbacks, however the relay code does. Instead of assigning default callbacks when there is none, add callback wrappers to conditionally call the client callbacks if available, and fall back to default behaviour (typically no-op) otherwise. This lets all relay users make their struct rchan_callbacks const data. This series starts with a number of cleanups first based on Christoph's feedback. This patch (of 9): No relay client uses the buf_mapped or buf_unmapped callbacks. Remove them. This makes relay's vm_operations_struct close callback a dummy, remove it as well. Link: https://lkml.kernel.org/r/cover.1606153547.git.jani.nikula@intel.com Link: https://lkml.kernel.org/r/c69fff6e0cd485563604240bbfcc028434983bec.1606153547.git.jani.nikula@intel.com Signed-off-by: Jani Nikula Suggested-by: Christoph Hellwig Reviewed-by: Christoph Hellwig Cc: Jens Axboe Cc: Kalle Valo Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/relay.h | 19 ------------------- kernel/relay.c | 34 ---------------------------------- 2 files changed, 53 deletions(-) diff --git a/include/linux/relay.h b/include/linux/relay.h index e13a333e7c37..b3c4f49f6951 100644 --- a/include/linux/relay.h +++ b/include/linux/relay.h @@ -101,25 +101,6 @@ struct rchan_callbacks void *prev_subbuf, size_t prev_padding); - /* - * buf_mapped - relay buffer mmap notification - * @buf: the channel buffer - * @filp: relay file pointer - * - * Called when a relay file is successfully mmapped - */ - void (*buf_mapped)(struct rchan_buf *buf, - struct file *filp); - - /* - * buf_unmapped - relay buffer unmap notification - * @buf: the channel buffer - * @filp: relay file pointer - * - * Called when a relay file is successfully unmapped - */ - void (*buf_unmapped)(struct rchan_buf *buf, - struct file *filp); /* * create_buf_file - create file to represent a relay channel buffer * @filename: the name of the file to create diff --git a/kernel/relay.c b/kernel/relay.c index b08d936d5fa7..b51343642bf4 100644 --- a/kernel/relay.c +++ b/kernel/relay.c @@ -27,15 +27,6 @@ static DEFINE_MUTEX(relay_channels_mutex); static LIST_HEAD(relay_channels); -/* - * close() vm_op implementation for relay file mapping. - */ -static void relay_file_mmap_close(struct vm_area_struct *vma) -{ - struct rchan_buf *buf = vma->vm_private_data; - buf->chan->cb->buf_unmapped(buf, vma->vm_file); -} - /* * fault() vm_op implementation for relay file mapping. */ @@ -62,7 +53,6 @@ static vm_fault_t relay_buf_fault(struct vm_fault *vmf) */ static const struct vm_operations_struct relay_file_mmap_ops = { .fault = relay_buf_fault, - .close = relay_file_mmap_close, }; /* @@ -96,7 +86,6 @@ static void relay_free_page_array(struct page **array) static int relay_mmap_buf(struct rchan_buf *buf, struct vm_area_struct *vma) { unsigned long length = vma->vm_end - vma->vm_start; - struct file *filp = vma->vm_file; if (!buf) return -EBADF; @@ -107,7 +96,6 @@ static int relay_mmap_buf(struct rchan_buf *buf, struct vm_area_struct *vma) vma->vm_ops = &relay_file_mmap_ops; vma->vm_flags |= VM_DONTEXPAND; vma->vm_private_data = buf; - buf->chan->cb->buf_mapped(buf, filp); return 0; } @@ -283,22 +271,6 @@ static int subbuf_start_default_callback (struct rchan_buf *buf, return 1; } -/* - * buf_mapped() default callback. Does nothing. - */ -static void buf_mapped_default_callback(struct rchan_buf *buf, - struct file *filp) -{ -} - -/* - * buf_unmapped() default callback. Does nothing. - */ -static void buf_unmapped_default_callback(struct rchan_buf *buf, - struct file *filp) -{ -} - /* * create_buf_file_create() default callback. Does nothing. */ @@ -322,8 +294,6 @@ static int remove_buf_file_default_callback(struct dentry *dentry) /* relay channel default callbacks */ static struct rchan_callbacks default_channel_callbacks = { .subbuf_start = subbuf_start_default_callback, - .buf_mapped = buf_mapped_default_callback, - .buf_unmapped = buf_unmapped_default_callback, .create_buf_file = create_buf_file_default_callback, .remove_buf_file = remove_buf_file_default_callback, }; @@ -509,10 +479,6 @@ static void setup_callbacks(struct rchan *chan, if (!cb->subbuf_start) cb->subbuf_start = subbuf_start_default_callback; - if (!cb->buf_mapped) - cb->buf_mapped = buf_mapped_default_callback; - if (!cb->buf_unmapped) - cb->buf_unmapped = buf_unmapped_default_callback; if (!cb->create_buf_file) cb->create_buf_file = create_buf_file_default_callback; if (!cb->remove_buf_file) -- cgit v1.2.3