From 68ab3d883a2df13f4b93a923bae3a287cbee29d3 Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Tue, 29 Apr 2008 01:03:46 -0700 Subject: [PATCH] relayfs: support larger relay buffer Use vmalloc() and memset() instead of kcalloc() to allocate a page* array when the array size is bigger than one page. This enables relayfs to support bigger relay buffers than 64MB on 4k-page system, 512MB on 16k-page system. [akpm@linux-foundation.org: cleanup] Signed-off-by: Masami Hiramatsu Cc: David Wilder Reviewed-by: Tom Zanussi Reviewed-by: Pekka Enberg Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/relay.c | 35 ++++++++++++++++++++++++++++++++--- 1 file changed, 32 insertions(+), 3 deletions(-) diff --git a/kernel/relay.c b/kernel/relay.c index d6204a48581..bc24dcdc570 100644 --- a/kernel/relay.c +++ b/kernel/relay.c @@ -65,6 +65,35 @@ static struct vm_operations_struct relay_file_mmap_ops = { .close = relay_file_mmap_close, }; +/* + * allocate an array of pointers of struct page + */ +static struct page **relay_alloc_page_array(unsigned int n_pages) +{ + struct page **array; + size_t pa_size = n_pages * sizeof(struct page *); + + if (pa_size > PAGE_SIZE) { + array = vmalloc(pa_size); + if (array) + memset(array, 0, pa_size); + } else { + array = kzalloc(pa_size, GFP_KERNEL); + } + return array; +} + +/* + * free an array of pointers of struct page + */ +static void relay_free_page_array(struct page **array) +{ + if (is_vmalloc_addr(array)) + vfree(array); + else + kfree(array); +} + /** * relay_mmap_buf: - mmap channel buffer to process address space * @buf: relay channel buffer @@ -109,7 +138,7 @@ static void *relay_alloc_buf(struct rchan_buf *buf, size_t *size) *size = PAGE_ALIGN(*size); n_pages = *size >> PAGE_SHIFT; - buf->page_array = kcalloc(n_pages, sizeof(struct page *), GFP_KERNEL); + buf->page_array = relay_alloc_page_array(n_pages); if (!buf->page_array) return NULL; @@ -130,7 +159,7 @@ static void *relay_alloc_buf(struct rchan_buf *buf, size_t *size) depopulate: for (j = 0; j < i; j++) __free_page(buf->page_array[j]); - kfree(buf->page_array); + relay_free_page_array(buf->page_array); return NULL; } @@ -189,7 +218,7 @@ static void relay_destroy_buf(struct rchan_buf *buf) vunmap(buf->start); for (i = 0; i < buf->page_count; i++) __free_page(buf->page_array[i]); - kfree(buf->page_array); + relay_free_page_array(buf->page_array); } chan->buf[buf->cpu] = NULL; kfree(buf->padding); -- 2.41.1