net/ceph/msgpool.c

   1 #include <linux/ceph/ceph_debug.h>
   2
   3 #include <linux/err.h>
   4 #include <linux/sched.h>
   5 #include <linux/types.h>
   6 #include <linux/vmalloc.h>
   7
   8 #include <linux/ceph/msgpool.h>
   9
  10 static void *alloc_fn(gfp_t gfp_mask, void *arg)
  11 {
  12         struct ceph_msgpool *pool = arg;
  13         void *p;
  14
  15         p = ceph_msg_new(0, pool->front_len, gfp_mask);
  16         if (!p)
  17                 pr_err("msgpool %s alloc failed\n", pool->name);
  18         return p;
  19 }
  20
  21 static void free_fn(void *element, void *arg)
  22 {
  23         ceph_msg_put(element);
  24 }
  25
  26 int ceph_msgpool_init(struct ceph_msgpool *pool,
  27                       int front_len, int size, bool blocking, const char *name)
  28 {
  29         pool->front_len = front_len;
  30         pool->pool = mempool_create(size, alloc_fn, free_fn, pool);
  31         if (!pool->pool)
  32                 return -ENOMEM;
  33         pool->name = name;
  34         return 0;
  35 }
  36
  37 void ceph_msgpool_destroy(struct ceph_msgpool *pool)
  38 {
  39         mempool_destroy(pool->pool);
  40 }
  41
  42 struct ceph_msg *ceph_msgpool_get(struct ceph_msgpool *pool,
  43                                   int front_len)
  44 {
  45         if (front_len > pool->front_len) {
  46                 pr_err("msgpool_get pool %s need front %d, pool size is %d\n",
  47                        pool->name, front_len, pool->front_len);
  48                 WARN_ON(1);
  49
  50                 /* try to alloc a fresh message */
  51                 return ceph_msg_new(0, front_len, GFP_NOFS);
  52         }
  53
  54         return mempool_alloc(pool->pool, GFP_NOFS);
  55 }
  56
  57 void ceph_msgpool_put(struct ceph_msgpool *pool, struct ceph_msg *msg)
  58 {
  59         /* reset msg front_len; user may have changed it */
  60         msg->front.iov_len = pool->front_len;
  61         msg->hdr.front_len = cpu_to_le32(pool->front_len);
  62
  63         kref_init(&msg->kref);  /* retake single ref */
  64 }