net/ceph/buffer.c

0001 // SPDX-License-Identifier: GPL-2.0
0002
0003 #include <linux/ceph/ceph_debug.h>
0004
0005 #include <linux/module.h>
0006 #include <linux/slab.h>
0007
0008 #include <linux/ceph/buffer.h>
0009 #include <linux/ceph/decode.h>
0010 #include <linux/ceph/libceph.h> /* for kvmalloc */
0011
0012 struct ceph_buffer *ceph_buffer_new(size_t len, gfp_t gfp)
0013 {
0014     struct ceph_buffer *b;
0015
0016     b = kmalloc(sizeof(*b), gfp);
0017     if (!b)
0018         return NULL;
0019
0020     b->vec.iov_base = kvmalloc(len, gfp);
0021     if (!b->vec.iov_base) {
0022         kfree(b);
0023         return NULL;
0024     }
0025
0026     kref_init(&b->kref);
0027     b->alloc_len = len;
0028     b->vec.iov_len = len;
0029     dout("buffer_new %p\n", b);
0030     return b;
0031 }
0032 EXPORT_SYMBOL(ceph_buffer_new);
0033
0034 void ceph_buffer_release(struct kref *kref)
0035 {
0036     struct ceph_buffer *b = container_of(kref, struct ceph_buffer, kref);
0037
0038     dout("buffer_release %p\n", b);
0039     kvfree(b->vec.iov_base);
0040     kfree(b);
0041 }
0042 EXPORT_SYMBOL(ceph_buffer_release);
0043
0044 int ceph_decode_buffer(struct ceph_buffer **b, void **p, void *end)
0045 {
0046     size_t len;
0047
0048     ceph_decode_need(p, end, sizeof(u32), bad);
0049     len = ceph_decode_32(p);
0050     dout("decode_buffer len %d\n", (int)len);
0051     ceph_decode_need(p, end, len, bad);
0052     *b = ceph_buffer_new(len, GFP_NOFS);
0053     if (!*b)
0054         return -ENOMEM;
0055     ceph_decode_copy(p, (*b)->vec.iov_base, len);
0056     return 0;
0057 bad:
0058     return -EINVAL;
0059 }