#include <linux/ceph/ceph_debug.h> #include <linux/err.h>#include <linux/sched.h>#include <linux/types.h>#include <linux/vmalloc.h> #include <linux/ceph/msgpool.h> static void *alloc_fn(gfp_t gfp_mask, void *arg){	struct ceph_msgpool *pool = arg;	void *p; 	p = ceph_msg_new(0, pool->front_len, gfp_mask);	if (!p)		pr_err("msgpool %s alloc failed\n", pool->name);	return p;} static void free_fn(void *element, void *arg){	ceph_msg_put(element);} int ceph_msgpool_init(struct ceph_msgpool *pool,		      int front_len, int size, bool blocking, const char *name){	pool->front_len = front_len;	pool->pool = mempool_create(size, alloc_fn, free_fn, pool);	if (!pool->pool)		return -ENOMEM;	pool->name = name;	return 0;} void ceph_msgpool_destroy(struct ceph_msgpool *pool){	mempool_destroy(pool->pool);} struct ceph_msg *ceph_msgpool_get(struct ceph_msgpool *pool,				  int front_len){	if (front_len > pool->front_len) {		pr_err("msgpool_get pool %s need front %d, pool size is %d\n",		       pool->name, front_len, pool->front_len);		WARN_ON(1); 		/* try to alloc a fresh message */		return ceph_msg_new(0, front_len, GFP_NOFS);	} 	return mempool_alloc(pool->pool, GFP_NOFS);} void ceph_msgpool_put(struct ceph_msgpool *pool, struct ceph_msg *msg){	/* reset msg front_len; user may have changed it */	msg->front.iov_len = pool->front_len;	msg->hdr.front_len = cpu_to_le32(pool->front_len); 	kref_init(&msg->kref);  /* retake single ref */}