linux/net/ceph/snapshot.c
Thomas Gleixner 04672fe6d6 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 268
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation this program is
  distributed in the hope that it will be useful but without any
  warranty without even the implied warranty of merchantability or
  fitness for a particular purpose see the gnu general public license
  for more details you should have received a copy of the gnu general
  public license along with this program if not write to the free
  software foundation inc 51 franklin street fifth floor boston ma
  02110 1301 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 46 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141334.135501091@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05 17:30:29 +02:00

64 lines
1.6 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* snapshot.c Ceph snapshot context utility routines (part of libceph)
*
* Copyright (C) 2013 Inktank Storage, Inc.
*/
#include <linux/types.h>
#include <linux/export.h>
#include <linux/ceph/libceph.h>
/*
* Ceph snapshot contexts are reference counted objects, and the
* returned structure holds a single reference. Acquire additional
* references with ceph_get_snap_context(), and release them with
* ceph_put_snap_context(). When the reference count reaches zero
* the entire structure is freed.
*/
/*
* Create a new ceph snapshot context large enough to hold the
* indicated number of snapshot ids (which can be 0). Caller has
* to fill in snapc->seq and snapc->snaps[0..snap_count-1].
*
* Returns a null pointer if an error occurs.
*/
struct ceph_snap_context *ceph_create_snap_context(u32 snap_count,
gfp_t gfp_flags)
{
struct ceph_snap_context *snapc;
size_t size;
size = sizeof (struct ceph_snap_context);
size += snap_count * sizeof (snapc->snaps[0]);
snapc = kzalloc(size, gfp_flags);
if (!snapc)
return NULL;
refcount_set(&snapc->nref, 1);
snapc->num_snaps = snap_count;
return snapc;
}
EXPORT_SYMBOL(ceph_create_snap_context);
struct ceph_snap_context *ceph_get_snap_context(struct ceph_snap_context *sc)
{
if (sc)
refcount_inc(&sc->nref);
return sc;
}
EXPORT_SYMBOL(ceph_get_snap_context);
void ceph_put_snap_context(struct ceph_snap_context *sc)
{
if (!sc)
return;
if (refcount_dec_and_test(&sc->nref)) {
/*printk(" deleting snap_context %p\n", sc);*/
kfree(sc);
}
}
EXPORT_SYMBOL(ceph_put_snap_context);