LXR linux/net/ceph/buffer.c

   1
   2#include <linux/ceph/ceph_debug.h>
   3
   4#include <linux/module.h>
   5#include <linux/slab.h>
   6
   7#include <linux/ceph/buffer.h>
   8#include <linux/ceph/decode.h>
   9
  10struct ceph_buffer *ceph_buffer_new(size_t len, gfp_t gfp)
  11{
  12        struct ceph_buffer *b;
  13
  14        b = kmalloc(sizeof(*b), gfp);
  15        if (!b)
  16                return NULL;
  17
  18        b->vec.iov_base = kmalloc(len, gfp | __GFP_NOWARN);
  19        if (b->vec.iov_base) {
  20                b->is_vmalloc = false;
  21        } else {
  22                b->vec.iov_base = __vmalloc(len, gfp | __GFP_HIGHMEM, PAGE_KERNEL);
  23                if (!b->vec.iov_base) {
  24                        kfree(b);
  25                        return NULL;
  26                }
  27                b->is_vmalloc = true;
  28        }
  29
  30        kref_init(&b->kref);
  31        b->alloc_len = len;
  32        b->vec.iov_len = len;
  33        dout("buffer_new %p\n", b);
  34        return b;
  35}
  36EXPORT_SYMBOL(ceph_buffer_new);
  37
  38void ceph_buffer_release(struct kref *kref)
  39{
  40        struct ceph_buffer *b = container_of(kref, struct ceph_buffer, kref);
  41
  42        dout("buffer_release %p\n", b);
  43        if (b->vec.iov_base) {
  44                if (b->is_vmalloc)
  45                        vfree(b->vec.iov_base);
  46                else
  47                        kfree(b->vec.iov_base);
  48        }
  49        kfree(b);
  50}
  51EXPORT_SYMBOL(ceph_buffer_release);
  52
  53int ceph_decode_buffer(struct ceph_buffer **b, void **p, void *end)
  54{
  55        size_t len;
  56
  57        ceph_decode_need(p, end, sizeof(u32), bad);
  58        len = ceph_decode_32(p);
  59        dout("decode_buffer len %d\n", (int)len);
  60        ceph_decode_need(p, end, len, bad);
  61        *b = ceph_buffer_new(len, GFP_NOFS);
  62        if (!*b)
  63                return -ENOMEM;
  64        ceph_decode_copy(p, (*b)->vec.iov_base, len);
  65        return 0;
  66bad:
  67        return -EINVAL;
  68}
  69