/*
 * super.c
 *
 * Copyright (C) 2001-2002 Will Dyson <will_dyson@pobox.com>
 *
 * Licensed under the GNU GPL. See the file COPYING for details.
 *
 */

#include <linux/fs.h>
#include <asm/page.h> /* for PAGE_SIZE */

#include "befs.h"
#include "super.h"

/*
 * befs_load_sb -- Read from disk and properly byteswap all the fields
 * of the befs superblock
 */
int
befs_load_sb(struct super_block *sb, befs_super_block *disk_sb)
{
	struct befs_sb_info *befs_sb = BEFS_SB(sb);

	/* Check the byte order of the filesystem */
	if (disk_sb->fs_byte_order == BEFS_BYTEORDER_NATIVE_LE)
		befs_sb->byte_order = BEFS_BYTESEX_LE;
	else if (disk_sb->fs_byte_order == BEFS_BYTEORDER_NATIVE_BE)
		befs_sb->byte_order = BEFS_BYTESEX_BE;

	befs_sb->magic1 = fs32_to_cpu(sb, disk_sb->magic1);
	befs_sb->magic2 = fs32_to_cpu(sb, disk_sb->magic2);
	befs_sb->magic3 = fs32_to_cpu(sb, disk_sb->magic3);
	befs_sb->block_size = fs32_to_cpu(sb, disk_sb->block_size);
	befs_sb->block_shift = fs32_to_cpu(sb, disk_sb->block_shift);
	befs_sb->num_blocks = fs64_to_cpu(sb, disk_sb->num_blocks);
	befs_sb->used_blocks = fs64_to_cpu(sb, disk_sb->used_blocks);
	befs_sb->inode_size = fs32_to_cpu(sb, disk_sb->inode_size);

	befs_sb->blocks_per_ag = fs32_to_cpu(sb, disk_sb->blocks_per_ag);
	befs_sb->ag_shift = fs32_to_cpu(sb, disk_sb->ag_shift);
	befs_sb->num_ags = fs32_to_cpu(sb, disk_sb->num_ags);

	befs_sb->flags = fs32_to_cpu(sb, disk_sb->flags);

	befs_sb->log_blocks = fsrun_to_cpu(sb, disk_sb->log_blocks);
	befs_sb->log_start = fs64_to_cpu(sb, disk_sb->log_start);
	befs_sb->log_end = fs64_to_cpu(sb, disk_sb->log_end);

	befs_sb->root_dir = fsrun_to_cpu(sb, disk_sb->root_dir);
	befs_sb->indices = fsrun_to_cpu(sb, disk_sb->indices);
	befs_sb->nls = NULL;

	return BEFS_OK;
}

int
befs_check_sb(struct super_block *sb)
{
	struct befs_sb_info *befs_sb = BEFS_SB(sb);

	/* Check magic headers of super block */
	if ((befs_sb->magic1 != BEFS_SUPER_MAGIC1)
	    || (befs_sb->magic2 != BEFS_SUPER_MAGIC2)
	    || (befs_sb->magic3 != BEFS_SUPER_MAGIC3)) {
		befs_error(sb, "invalid magic header");
		return BEFS_ERR;
	}

	/*
	 * Check blocksize of BEFS.
	 *
	 * Blocksize of BEFS is 1024, 2048, 4096 or 8192.
	 */

	if ((befs_sb->block_size != 1024)
	    && (befs_sb->block_size != 2048)
	    && (befs_sb->block_size != 4096)
	    && (befs_sb->block_size != 8192)) {
		befs_error(sb, "invalid blocksize: %u", befs_sb->block_size);
		return BEFS_ERR;
	}

	if (befs_sb->block_size > PAGE_SIZE) {
		befs_error(sb, "blocksize(%u) cannot be larger "
			   "than system pagesize(%lu)", befs_sb->block_size,
			   PAGE_SIZE);
		return BEFS_ERR;
	}

	/*
	 * block_shift and block_size encode the same information
	 * in different ways as a consistency check.
	 */

	if ((1 << befs_sb->block_shift) != befs_sb->block_size) {
		befs_error(sb, "block_shift disagrees with block_size. "
			   "Corruption likely.");
		return BEFS_ERR;
	}


	/* ag_shift also encodes the same information as blocks_per_ag in a
	 * different way, non-fatal consistency check
	 */
	if ((1 << befs_sb->ag_shift) != befs_sb->blocks_per_ag)
		befs_error(sb, "ag_shift disagrees with blocks_per_ag.");

	if (befs_sb->log_start != befs_sb->log_end ||
	    befs_sb->flags == BEFS_DIRTY) {
		befs_error(sb, "Filesystem not clean! There are blocks in the "
			   "journal. You must boot into BeOS and mount this "
			   "volume to make it clean.");
		return BEFS_ERR;
	}

	return BEFS_OK;
}
div><div class='content'><div class='cgit-panel'><b>diff options</b><form method='get'><input type='hidden' name='h' value='nds-private-remove'/><input type='hidden' name='id' value='c8f325a59cfc718d13a50fbc746ed9b415c25e92'/><table><tr><td colspan='2'/></tr><tr><td class='label'>context:</td><td class='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/net/sched/sch_sfq.c?h=nds-private-remove&amp;id=c8f325a59cfc718d13a50fbc746ed9b415c25e92'>c8f325a59cfc718d13a50fbc746ed9b415c25e92</a> (<a href='/cgit.cgi/linux/net-next.git/patch/net/sched/sch_sfq.c?id=c8f325a59cfc718d13a50fbc746ed9b415c25e92'>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=c8f325a59cfc718d13a50fbc746ed9b415c25e92'>d53fbdac9d0781e39a13b2ac6b2bd258cf3b4140</a> /<a href='/cgit.cgi/linux/net-next.git/tree/net/sched/sch_sfq.c?h=nds-private-remove&amp;id=c8f325a59cfc718d13a50fbc746ed9b415c25e92'>net/sched/sch_sfq.c</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/net/sched/sch_sfq.c?h=nds-private-remove&amp;id=bf29bddf0417a4783da3b24e8c9e017ac649326f'>bf29bddf0417a4783da3b24e8c9e017ac649326f</a> (<a href='/cgit.cgi/linux/net-next.git/diff/net/sched/sch_sfq.c?h=nds-private-remove&amp;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/?h=nds-private-remove&amp;id=c8f325a59cfc718d13a50fbc746ed9b415c25e92'>Diffstat</a> (limited to 'net/sched/sch_sfq.c')</div><table summary='diffstat' class='diffstat'>