/**
 * aops.h - Defines for NTFS kernel address space operations and page cache
 *	    handling.  Part of the Linux-NTFS project.
 *
 * Copyright (c) 2001-2004 Anton Altaparmakov
 * Copyright (c) 2002 Richard Russon
 *
 * This program/include file is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as published
 * by the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program/include file 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 (in the main directory of the Linux-NTFS
 * distribution in the file COPYING); if not, write to the Free Software
 * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#ifndef _LINUX_NTFS_AOPS_H
#define _LINUX_NTFS_AOPS_H

#include <linux/mm.h>
#include <linux/highmem.h>
#include <linux/pagemap.h>
#include <linux/fs.h>

#include "inode.h"

/**
 * ntfs_unmap_page - release a page that was mapped using ntfs_map_page()
 * @page:	the page to release
 *
 * Unpin, unmap and release a page that was obtained from ntfs_map_page().
 */
static inline void ntfs_unmap_page(struct page *page)
{
	kunmap(page);
	put_page(page);
}

/**
 * ntfs_map_page - map a page into accessible memory, reading it if necessary
 * @mapping:	address space for which to obtain the page
 * @index:	index into the page cache for @mapping of the page to map
 *
 * Read a page from the page cache of the address space @mapping at position
 * @index, where @index is in units of PAGE_SIZE, and not in bytes.
 *
 * If the page is not in memory it is loaded from disk first using the readpage
 * method defined in the address space operations of @mapping and the page is
 * added to the page cache of @mapping in the process.
 *
 * If the page belongs to an mst protected attribute and it is marked as such
 * in its ntfs inode (NInoMstProtected()) the mst fixups are applied but no
 * error checking is performed.  This means the caller has to verify whether
 * the ntfs record(s) contained in the page are valid or not using one of the
 * ntfs_is_XXXX_record{,p}() macros, where XXXX is the record type you are
 * expecting to see.  (For details of the macros, see fs/ntfs/layout.h.)
 *
 * If the page is in high memory it is mapped into memory directly addressible
 * by the kernel.
 *
 * Finally the page count is incremented, thus pinning the page into place.
 *
 * The above means that page_address(page) can be used on all pages obtained
 * with ntfs_map_page() to get the kernel virtual address of the page.
 *
 * When finished with the page, the caller has to call ntfs_unmap_page() to
 * unpin, unmap and release the page.
 *
 * Note this does not grant exclusive access. If such is desired, the caller
 * must provide it independently of the ntfs_{un}map_page() calls by using
 * a {rw_}semaphore or other means of serialization. A spin lock cannot be
 * used as ntfs_map_page() can block.
 *
 * The unlocked and uptodate page is returned on success or an encoded error
 * on failure. Caller has to test for error using the IS_ERR() macro on the
 * return value. If that evaluates to 'true', the negative error code can be
 * obtained using PTR_ERR() on the return value of ntfs_map_page().
 */
static inline struct page *ntfs_map_page(struct address_space *mapping,
		unsigned long index)
{
	struct page *page = read_mapping_page(mapping, index, NULL);

	if (!IS_ERR(page)) {
		kmap(page);
		if (!PageError(page))
			return page;
		ntfs_unmap_page(page);
		return ERR_PTR(-EIO);
	}
	return page;
}

#ifdef NTFS_RW

extern void mark_ntfs_record_dirty(struct page *page, const unsigned int ofs);

#endif /* NTFS_RW */

#endif /* _LINUX_NTFS_AOPS_H */
option value='7'>7</option><option value='8'>8</option><option value='9'>9</option><option value='10'>10</option><option value='15'>15</option><option value='20'>20</option><option value='25'>25</option><option value='30'>30</option><option value='35'>35</option><option value='40'>40</option></select></td></tr><tr><td class='label'>space:</td><td class='ctrl'><select name='ignorews' onchange='this.form.submit();'><option value='0' selected='selected'>include</option><option value='1'>ignore</option></select></td></tr><tr><td class='label'>mode:</td><td class='ctrl'><select name='dt' onchange='this.form.submit();'><option value='0' selected='selected'>unified</option><option value='1'>ssdiff</option><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>Tony Lindgren &lt;tony@atomide.com&gt;</td><td class='right'>2017-01-19 08:49:07 -0800</td></tr>
<tr><th>committer</th><td>Vinod Koul &lt;vinod.koul@intel.com&gt;</td><td class='right'>2017-01-25 11:29:11 +0530</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/net/rxrpc/security.c?h=nds-private-remove&amp;id=ae4a3e028bb8b59e7cfeb0cc9ef03d885182ce8b'>ae4a3e028bb8b59e7cfeb0cc9ef03d885182ce8b</a> (<a href='/cgit.cgi/linux/net-next.git/patch/net/rxrpc/security.c?id=ae4a3e028bb8b59e7cfeb0cc9ef03d885182ce8b'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?h=nds-private-remove&amp;id=ae4a3e028bb8b59e7cfeb0cc9ef03d885182ce8b'>139fc7e29f97d6bb6c4dca2a97be2dc3f824bd51</a> /<a href='/cgit.cgi/linux/net-next.git/tree/net/rxrpc/security.c?h=nds-private-remove&amp;id=ae4a3e028bb8b59e7cfeb0cc9ef03d885182ce8b'>net/rxrpc/security.c</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/net/rxrpc/security.c?h=nds-private-remove&amp;id=49def1853334396f948dcb4cedb9347abb318df5'>49def1853334396f948dcb4cedb9347abb318df5</a> (<a href='/cgit.cgi/linux/net-next.git/diff/net/rxrpc/security.c?h=nds-private-remove&amp;id=ae4a3e028bb8b59e7cfeb0cc9ef03d885182ce8b&amp;id2=49def1853334396f948dcb4cedb9347abb318df5'>diff</a>)</td></tr></table>
<div class='commit-subject'>dmaengine: cppi41: Fix runtime PM timeouts with USB mass storage</div><div class='commit-msg'>Commit fdea2d09b997 ("dmaengine: cppi41: Add basic PM runtime support")
added runtime PM support for cppi41, but had corner case issues. Some of
the issues were fixed with commit 098de42ad670 ("dmaengine: cppi41: Fix
unpaired pm runtime when only a USB hub is connected"). That fix however
caused a new regression where we can get error -115 messages with USB on
BeagleBone when connecting a USB mass storage device to a hub.

This is because when connecting a USB mass storage device to a hub, the
initial DMA transfers can take over 200ms to complete and cppi41
autosuspend delay times out.

To fix the issue, we want to implement refcounting for chan_busy array
that contains the active dma transfers. Increasing the autosuspend delay
won't help as that the delay could be potentially seconds, and it's best
to let the USB subsystem to deal with the timeouts on errors.

The earlier attempt for runtime PM was buggy as the pm_runtime_get/put()
calls could get unpaired easily as they did not follow the state of
the chan_busy array as described in commit 098de42ad670 ("dmaengine:
cppi41: Fix unpaired pm runtime when only a USB hub is connected".

Let's fix the issue by adding pm_runtime_get() to where a new transfer
is added to the chan_busy array, and calls to pm_runtime_put() where
chan_busy array entry is cleared. This prevents any autosuspend timeouts
from happening while dma transfers are active.

Fixes: 098de42ad670 ("dmaengine: cppi41: Fix unpaired pm runtime when
only a USB hub is connected")
Fixes: fdea2d09b997 ("dmaengine: cppi41: Add basic PM runtime support")
Cc: Andy Shevchenko &lt;andy.shevchenko@gmail.com&gt;
Cc: Bin Liu &lt;b-liu@ti.com&gt;
Cc: Grygorii Strashko &lt;grygorii.strashko@ti.com&gt;
Cc: Kevin Hilman &lt;khilman@baylibre.com&gt;
Cc: Patrick Titiano &lt;ptitiano@baylibre.com&gt;
Cc: Sergei Shtylyov &lt;sergei.shtylyov@cogentembedded.com&gt;
Signed-off-by: Tony Lindgren &lt;tony@atomide.com&gt;
Tested-by: Bin Liu &lt;b-liu@ti.com&gt;
Signed-off-by: Vinod Koul &lt;vinod.koul@intel.com&gt;
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?h=nds-private-remove&amp;id=ae4a3e028bb8b59e7cfeb0cc9ef03d885182ce8b'>Diffstat</a> (limited to 'net/rxrpc/security.c')</div><table summary='diffstat' class='diffstat'>