/*
 * snapshot.c    Ceph snapshot context utility routines (part of libceph)
 *
 * Copyright (C) 2013 Inktank Storage, Inc.
 *
 * 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.
 */

#include <stddef.h>

#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;

	atomic_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)
		atomic_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 (atomic_dec_and_test(&sc->nref)) {
		/*printk(" deleting snap_context %p\n", sc);*/
		kfree(sc);
	}
}
EXPORT_SYMBOL(ceph_put_snap_context);
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option value='2'>stat only</option></select></td></tr><tr><td/><td class='ctrl'><noscript><input type='submit' value='reload'/></noscript></td></tr></table></form></div><table summary='commit info' class='commit-info'>
<tr><th>author</th><td>Mauro Carvalho Chehab &lt;mchehab@s-opensource.com&gt;</td><td class='right'>2016-11-12 12:46:27 -0200</td></tr>
<tr><th>committer</th><td>Linus Torvalds &lt;torvalds@linux-foundation.org&gt;</td><td class='right'>2016-11-13 10:02:22 -0800</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/?id=1596c387e970cb680d4031fbe4d6eb2c2a4ddb63'>1596c387e970cb680d4031fbe4d6eb2c2a4ddb63</a> (<a href='/cgit.cgi/linux/net-next.git/patch/?id=1596c387e970cb680d4031fbe4d6eb2c2a4ddb63'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?id=1596c387e970cb680d4031fbe4d6eb2c2a4ddb63'>ccac90cf3c0b1fc6ee3fa04b0f14f94ce9975d90</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/?id=7724325a19fb0a51d2a69bd2915b33f0ff197f5a'>7724325a19fb0a51d2a69bd2915b33f0ff197f5a</a> (<a href='/cgit.cgi/linux/net-next.git/diff/?id=1596c387e970cb680d4031fbe4d6eb2c2a4ddb63&amp;id2=7724325a19fb0a51d2a69bd2915b33f0ff197f5a'>diff</a>)</td></tr></table>
<div class='commit-subject'>gp8psk: fix gp8psk_usb_in_op() logic</div><div class='commit-msg'>Commit bc29131ecb10 ("[media] gp8psk: don't do DMA on stack") fixed the
usage of DMA on stack, but the memcpy was wrong for gp8psk_usb_in_op().
Fix it.

From Derek's email:
    "Fix confirmed using 2 different Skywalker models with
     HD mpeg4, SD mpeg2."

Suggested-by: Johannes Stezenbach &lt;js@linuxtv.org&gt;
Fixes: bc29131ecb10 ("[media] gp8psk: don't do DMA on stack")
Tested-by: Derek &lt;user.vdr@gmail.com&gt;
Signed-off-by: Mauro Carvalho Chehab &lt;mchehab@s-opensource.com&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?id=1596c387e970cb680d4031fbe4d6eb2c2a4ddb63'>Diffstat</a></div><table summary='diffstat' class='diffstat'>