ceph: ref counted buffer

[mirror_ubuntu-artful-kernel.git] / fs / ceph / buffer.c

#include "ceph_debug.h"
#include "buffer.h"

struct ceph_buffer *ceph_buffer_new(gfp_t gfp)
{
	struct ceph_buffer *b;

	b = kmalloc(sizeof(*b), gfp);
	if (!b)
		return NULL;
	atomic_set(&b->nref, 1);
	b->vec.iov_base = NULL;
	b->vec.iov_len = 0;
	b->alloc_len = 0;
	return b;
}

int ceph_buffer_alloc(struct ceph_buffer *b, int len, gfp_t gfp)
{
	b->vec.iov_base = kmalloc(len, gfp | __GFP_NOWARN);
	if (b->vec.iov_base) {
		b->is_vmalloc = false;
	} else {
		b->vec.iov_base = __vmalloc(len, gfp, PAGE_KERNEL);
		b->is_vmalloc = true;
	}
	if (!b->vec.iov_base)
		return -ENOMEM;
	b->alloc_len = len;
	b->vec.iov_len = len;
	return 0;
}