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
  10 struct 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 }
  36 EXPORT_SYMBOL(ceph_buffer_new);
  37
  38 void 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 }
  51 EXPORT_SYMBOL(ceph_buffer_release);
  52
  53 int 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;
  66 bad:
  67         return -EINVAL;
  68 }