/*
 * f2fs IO tracer
 *
 * Copyright (c) 2014 Motorola Mobility
 * Copyright (c) 2014 Jaegeuk Kim <jaegeuk@kernel.org>
 *
 * 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.
 */
#include <linux/fs.h>
#include <linux/f2fs_fs.h>
#include <linux/sched.h>
#include <linux/radix-tree.h>

#include "f2fs.h"
#include "trace.h"

static RADIX_TREE(pids, GFP_ATOMIC);
static spinlock_t pids_lock;
static struct last_io_info last_io;

static inline void __print_last_io(void)
{
	if (!last_io.len)
		return;

	trace_printk("%3x:%3x %4x %-16s %2x %5x %5x %12x %4x\n",
			last_io.major, last_io.minor,
			last_io.pid, "----------------",
			last_io.type,
			last_io.fio.op, last_io.fio.op_flags,
			last_io.fio.new_blkaddr,
			last_io.len);
	memset(&last_io, 0, sizeof(last_io));
}

static int __file_type(struct inode *inode, pid_t pid)
{
	if (f2fs_is_atomic_file(inode))
		return __ATOMIC_FILE;
	else if (f2fs_is_volatile_file(inode))
		return __VOLATILE_FILE;
	else if (S_ISDIR(inode->i_mode))
		return __DIR_FILE;
	else if (inode->i_ino == F2FS_NODE_INO(F2FS_I_SB(inode)))
		return __NODE_FILE;
	else if (inode->i_ino == F2FS_META_INO(F2FS_I_SB(inode)))
		return __META_FILE;
	else if (pid)
		return __NORMAL_FILE;
	else
		return __MISC_FILE;
}

void f2fs_trace_pid(struct page *page)
{
	struct inode *inode = page->mapping->host;
	pid_t pid = task_pid_nr(current);
	void *p;

	page->private = pid;

	if (radix_tree_preload(GFP_NOFS))
		return;

	spin_lock(&pids_lock);
	p = radix_tree_lookup(&pids, pid);
	if (p == current)
		goto out;
	if (p)
		radix_tree_delete(&pids, pid);

	f2fs_radix_tree_insert(&pids, pid, current);

	trace_printk("%3x:%3x %4x %-16s\n",
			MAJOR(inode->i_sb->s_dev), MINOR(inode->i_sb->s_dev),
			pid, current->comm);
out:
	spin_unlock(&pids_lock);
	radix_tree_preload_end();
}

void f2fs_trace_ios(struct f2fs_io_info *fio, int flush)
{
	struct inode *inode;
	pid_t pid;
	int major, minor;

	if (flush) {
		__print_last_io();
		return;
	}

	inode = fio->page->mapping->host;
	pid = page_private(fio->page);

	major = MAJOR(inode->i_sb->s_dev);
	minor = MINOR(inode->i_sb->s_dev);

	if (last_io.major == major && last_io.minor == minor &&
			last_io.pid == pid &&
			last_io.type == __file_type(inode, pid) &&
			last_io.fio.op == fio->op &&
			last_io.fio.op_flags == fio->op_flags &&
			last_io.fio.new_blkaddr + last_io.len ==
							fio->new_blkaddr) {
		last_io.len++;
		return;
	}

	__print_last_io();

	last_io.major = major;
	last_io.minor = minor;
	last_io.pid = pid;
	last_io.type = __file_type(inode, pid);
	last_io.fio = *fio;
	last_io.len = 1;
	return;
}

void f2fs_build_trace_ios(void)
{
	spin_lock_init(&pids_lock);
}

#define PIDVEC_SIZE	128
static unsigned int gang_lookup_pids(pid_t *results, unsigned long first_index,
							unsigned int max_items)
{
	struct radix_tree_iter iter;
	void **slot;
	unsigned int ret = 0;

	if (unlikely(!max_items))
		return 0;

	radix_tree_for_each_slot(slot, &pids, &iter, first_index) {
		results[ret] = iter.index;
		if (++ret == PIDVEC_SIZE)
			break;
	}
	return ret;
}

void f2fs_destroy_trace_ios(void)
{
	pid_t pid[PIDVEC_SIZE];
	pid_t next_pid = 0;
	unsigned int found;

	spin_lock(&pids_lock);
	while ((found = gang_lookup_pids(pid, next_pid, PIDVEC_SIZE))) {
		unsigned idx;

		next_pid = pid[found - 1] + 1;
		for (idx = 0; idx < found; idx++)
			radix_tree_delete(&pids, pid[idx]);
	}
	spin_unlock(&pids_lock);
}
ctrl'><select name='context' onchange='this.form.submit();'><option value='1'>1</option><option value='2'>2</option><option value='3' selected='selected'>3</option><option value='4'>4</option><option value='5'>5</option><option value='6'>6</option><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>Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;</td><td class='right'>2017-02-01 17:45:02 +0000</td></tr>
<tr><th>committer</th><td>Ingo Molnar &lt;mingo@kernel.org&gt;</td><td class='right'>2017-02-01 21:17:49 +0100</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/include/trace/events/xen.h?id=c8f325a59cfc718d13a50fbc746ed9b415c25e92'>c8f325a59cfc718d13a50fbc746ed9b415c25e92</a> (<a href='/cgit.cgi/linux/net-next.git/patch/include/trace/events/xen.h?id=c8f325a59cfc718d13a50fbc746ed9b415c25e92'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?id=c8f325a59cfc718d13a50fbc746ed9b415c25e92'>d53fbdac9d0781e39a13b2ac6b2bd258cf3b4140</a> /<a href='/cgit.cgi/linux/net-next.git/tree/include/trace/events/xen.h?id=c8f325a59cfc718d13a50fbc746ed9b415c25e92'>include/trace/events/xen.h</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/include/trace/events/xen.h?id=bf29bddf0417a4783da3b24e8c9e017ac649326f'>bf29bddf0417a4783da3b24e8c9e017ac649326f</a> (<a href='/cgit.cgi/linux/net-next.git/diff/include/trace/events/xen.h?id=c8f325a59cfc718d13a50fbc746ed9b415c25e92&amp;id2=bf29bddf0417a4783da3b24e8c9e017ac649326f'>diff</a>)</td></tr></table>
<div class='commit-subject'>efi/fdt: Avoid FDT manipulation after ExitBootServices()</div><div class='commit-msg'>Some AArch64 UEFI implementations disable the MMU in ExitBootServices(),
after which unaligned accesses to RAM are no longer supported.

Commit:

  abfb7b686a3e ("efi/libstub/arm*: Pass latest memory map to the kernel")

fixed an issue in the memory map handling of the stub FDT code, but
inadvertently created an issue with such firmware, by moving some
of the FDT manipulation to after the invocation of ExitBootServices().

Given that the stub's libfdt implementation uses the ordinary, accelerated
string functions, which rely on hardware handling of unaligned accesses,
manipulating the FDT with the MMU off may result in alignment faults.

So fix the situation by moving the update_fdt_memmap() call into the
callback function invoked by efi_exit_boot_services() right before it
calls the ExitBootServices() UEFI service (which is arguably a better
place for it anyway)

Note that disabling the MMU in ExitBootServices() is not compliant with
the UEFI spec, and carries great risk due to the fact that switching from
cached to uncached memory accesses halfway through compiler generated code
(i.e., involving a stack) can never be done in a way that is architecturally
safe.

Fixes: abfb7b686a3e ("efi/libstub/arm*: Pass latest memory map to the kernel")
Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Tested-by: Riku Voipio &lt;riku.voipio@linaro.org&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Cc: mark.rutland@arm.com
Cc: linux-efi@vger.kernel.org
Cc: matt@codeblueprint.co.uk
Cc: leif.lindholm@linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1485971102-23330-2-git-send-email-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?id=c8f325a59cfc718d13a50fbc746ed9b415c25e92'>Diffstat</a> (limited to 'include/trace/events/xen.h')</div><table summary='diffstat' class='diffstat'>