diff options
Diffstat (limited to 'kernel/relay.c')
| -rw-r--r-- | kernel/relay.c | 109 |
1 files changed, 12 insertions, 97 deletions
diff --git a/kernel/relay.c b/kernel/relay.c index b08d936d5fa7..d1a67fbb819d 100644 --- a/kernel/relay.c +++ b/kernel/relay.c @@ -28,15 +28,6 @@ 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. */ static vm_fault_t relay_buf_fault(struct vm_fault *vmf) @@ -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; } @@ -264,70 +252,16 @@ EXPORT_SYMBOL_GPL(relay_buf_full); * High-level relay kernel API and associated functions. */ -/* - * rchan_callback implementations defining default channel behavior. Used - * in place of corresponding NULL values in client callback struct. - */ - -/* - * subbuf_start() default callback. Does nothing. - */ -static int subbuf_start_default_callback (struct rchan_buf *buf, - void *subbuf, - void *prev_subbuf, - size_t prev_padding) -{ - if (relay_buf_full(buf)) - return 0; - - 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. - */ -static struct dentry *create_buf_file_default_callback(const char *filename, - struct dentry *parent, - umode_t mode, - struct rchan_buf *buf, - int *is_global) +static int relay_subbuf_start(struct rchan_buf *buf, void *subbuf, + void *prev_subbuf, size_t prev_padding) { - return NULL; -} + if (!buf->chan->cb->subbuf_start) + return !relay_buf_full(buf); -/* - * remove_buf_file() default callback. Does nothing. - */ -static int remove_buf_file_default_callback(struct dentry *dentry) -{ - return -EINVAL; + return buf->chan->cb->subbuf_start(buf, subbuf, + prev_subbuf, prev_padding); } -/* 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, -}; - /** * wakeup_readers - wake up readers waiting on a channel * @work: contains the channel buffer @@ -371,7 +305,7 @@ static void __relay_reset(struct rchan_buf *buf, unsigned int init) for (i = 0; i < buf->chan->n_subbufs; i++) buf->padding[i] = 0; - buf->chan->cb->subbuf_start(buf, buf->data, NULL, 0); + relay_subbuf_start(buf, buf->data, NULL, 0); } /** @@ -499,27 +433,6 @@ static void relay_close_buf(struct rchan_buf *buf) kref_put(&buf->kref, relay_remove_buf); } -static void setup_callbacks(struct rchan *chan, - struct rchan_callbacks *cb) -{ - if (!cb) { - chan->cb = &default_channel_callbacks; - return; - } - - 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) - cb->remove_buf_file = remove_buf_file_default_callback; - chan->cb = cb; -} - int relay_prepare_cpu(unsigned int cpu) { struct rchan *chan; @@ -565,7 +478,7 @@ struct rchan *relay_open(const char *base_filename, struct dentry *parent, size_t subbuf_size, size_t n_subbufs, - struct rchan_callbacks *cb, + const struct rchan_callbacks *cb, void *private_data) { unsigned int i; @@ -576,6 +489,8 @@ struct rchan *relay_open(const char *base_filename, return NULL; if (subbuf_size > UINT_MAX / n_subbufs) return NULL; + if (!cb || !cb->create_buf_file || !cb->remove_buf_file) + return NULL; chan = kzalloc(sizeof(struct rchan), GFP_KERNEL); if (!chan) @@ -597,7 +512,7 @@ struct rchan *relay_open(const char *base_filename, chan->has_base_filename = 1; strlcpy(chan->base_filename, base_filename, NAME_MAX); } - setup_callbacks(chan, cb); + chan->cb = cb; kref_init(&chan->kref); mutex_lock(&relay_channels_mutex); @@ -780,7 +695,7 @@ size_t relay_switch_subbuf(struct rchan_buf *buf, size_t length) new_subbuf = buf->subbufs_produced % buf->chan->n_subbufs; new = buf->start + new_subbuf * buf->chan->subbuf_size; buf->offset = 0; - if (!buf->chan->cb->subbuf_start(buf, new, old, buf->prev_padding)) { + if (!relay_subbuf_start(buf, new, old, buf->prev_padding)) { buf->offset = buf->chan->subbuf_size + 1; return 0; } |