/*
 * symlink.c
 *
 * PURPOSE
 *	Symlink handling routines for the OSTA-UDF(tm) filesystem.
 *
 * COPYRIGHT
 *	This file is distributed under the terms of the GNU General Public
 *	License (GPL). Copies of the GPL can be obtained from:
 *		ftp://prep.ai.mit.edu/pub/gnu/GPL
 *	Each contributing author retains all rights to their own work.
 *
 *  (C) 1998-2001 Ben Fennema
 *  (C) 1999 Stelias Computing Inc
 *
 * HISTORY
 *
 *  04/16/99 blf  Created.
 *
 */

#include "udfdecl.h"
#include <linux/uaccess.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/time.h>
#include <linux/mm.h>
#include <linux/stat.h>
#include <linux/pagemap.h>
#include "udf_i.h"

static int udf_pc_to_char(struct super_block *sb, unsigned char *from,
			  int fromlen, unsigned char *to, int tolen)
{
	struct pathComponent *pc;
	int elen = 0;
	int comp_len;
	unsigned char *p = to;

	/* Reserve one byte for terminating \0 */
	tolen--;
	while (elen < fromlen) {
		pc = (struct pathComponent *)(from + elen);
		elen += sizeof(struct pathComponent);
		switch (pc->componentType) {
		case 1:
			/*
			 * Symlink points to some place which should be agreed
 			 * upon between originator and receiver of the media. Ignore.
			 */
			if (pc->lengthComponentIdent > 0) {
				elen += pc->lengthComponentIdent;
				break;
			}
			/* Fall through */
		case 2:
			if (tolen == 0)
				return -ENAMETOOLONG;
			p = to;
			*p++ = '/';
			tolen--;
			break;
		case 3:
			if (tolen < 3)
				return -ENAMETOOLONG;
			memcpy(p, "../", 3);
			p += 3;
			tolen -= 3;
			break;
		case 4:
			if (tolen < 2)
				return -ENAMETOOLONG;
			memcpy(p, "./", 2);
			p += 2;
			tolen -= 2;
			/* that would be . - just ignore */
			break;
		case 5:
			elen += pc->lengthComponentIdent;
			if (elen > fromlen)
				return -EIO;
			comp_len = udf_get_filename(sb, pc->componentIdent,
						    pc->lengthComponentIdent,
						    p, tolen);
			if (comp_len < 0)
				return comp_len;

			p += comp_len;
			tolen -= comp_len;
			if (tolen == 0)
				return -ENAMETOOLONG;
			*p++ = '/';
			tolen--;
			break;
		}
	}
	if (p > to + 1)
		p[-1] = '\0';
	else
		p[0] = '\0';
	return 0;
}

static int udf_symlink_filler(struct file *file, struct page *page)
{
	struct inode *inode = page->mapping->host;
	struct buffer_head *bh = NULL;
	unsigned char *symlink;
	int err;
	unsigned char *p = page_address(page);
	struct udf_inode_info *iinfo;
	uint32_t pos;

	/* We don't support symlinks longer than one block */
	if (inode->i_size > inode->i_sb->s_blocksize) {
		err = -ENAMETOOLONG;
		goto out_unmap;
	}

	iinfo = UDF_I(inode);
	pos = udf_block_map(inode, 0);

	down_read(&iinfo->i_data_sem);
	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
		symlink = iinfo->i_ext.i_data + iinfo->i_lenEAttr;
	} else {
		bh = sb_bread(inode->i_sb, pos);

		if (!bh) {
			err = -EIO;
			goto out_unlock_inode;
		}

		symlink = bh->b_data;
	}

	err = udf_pc_to_char(inode->i_sb, symlink, inode->i_size, p, PAGE_SIZE);
	brelse(bh);
	if (err)
		goto out_unlock_inode;

	up_read(&iinfo->i_data_sem);
	SetPageUptodate(page);
	unlock_page(page);
	return 0;

out_unlock_inode:
	up_read(&iinfo->i_data_sem);
	SetPageError(page);
out_unmap:
	unlock_page(page);
	return err;
}

/*
 * symlinks can't do much...
 */
const struct address_space_operations udf_symlink_aops = {
	.readpage		= udf_symlink_filler,
};
net-next.git/commit/kernel/trace/trace_hwlat.c?h=nds-private-remove&amp;id=0becc0ae5b42828785b589f686725ff5bc3b9b25'>trace_hwlat.c</a></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='0becc0ae5b42828785b589f686725ff5bc3b9b25'/><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>Thomas Gleixner &lt;tglx@linutronix.de&gt;</td><td class='right'>2017-01-31 09:37:34 +0100</td></tr>
<tr><th>committer</th><td>Thomas Gleixner &lt;tglx@linutronix.de&gt;</td><td class='right'>2017-01-31 21:47:58 +0100</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/kernel/trace/trace_hwlat.c?h=nds-private-remove&amp;id=0becc0ae5b42828785b589f686725ff5bc3b9b25'>0becc0ae5b42828785b589f686725ff5bc3b9b25</a> (<a href='/cgit.cgi/linux/net-next.git/patch/kernel/trace/trace_hwlat.c?id=0becc0ae5b42828785b589f686725ff5bc3b9b25'>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=0becc0ae5b42828785b589f686725ff5bc3b9b25'>be6d0e1f37c38ed0a7dd5da2d4b1e93f0fb43101</a> /<a href='/cgit.cgi/linux/net-next.git/tree/kernel/trace/trace_hwlat.c?h=nds-private-remove&amp;id=0becc0ae5b42828785b589f686725ff5bc3b9b25'>kernel/trace/trace_hwlat.c</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/kernel/trace/trace_hwlat.c?h=nds-private-remove&amp;id=24c2503255d35c269b67162c397a1a1c1e02f6ce'>24c2503255d35c269b67162c397a1a1c1e02f6ce</a> (<a href='/cgit.cgi/linux/net-next.git/diff/kernel/trace/trace_hwlat.c?h=nds-private-remove&amp;id=0becc0ae5b42828785b589f686725ff5bc3b9b25&amp;id2=24c2503255d35c269b67162c397a1a1c1e02f6ce'>diff</a>)</td></tr></table>
<div class='commit-subject'>x86/mce: Make timer handling more robust</div><div class='commit-msg'>Erik reported that on a preproduction hardware a CMCI storm triggers the
BUG_ON in add_timer_on(). The reason is that the per CPU MCE timer is
started by the CMCI logic before the MCE CPU hotplug callback starts the
timer with add_timer_on(). So the timer is already queued which triggers
the BUG.

Using add_timer_on() is pretty pointless in this code because the timer is
strictlty per CPU, initialized as pinned and all operations which arm the
timer happen on the CPU to which the timer belongs.

Simplify the whole machinery by using mod_timer() instead of add_timer_on()
which avoids the problem because mod_timer() can handle already queued
timers. Use __start_timer() everywhere so the earliest armed expiry time is
preserved.

Reported-by: Erik Veijola &lt;erik.veijola@intel.com&gt;
Tested-by: Borislav Petkov &lt;bp@alien8.de&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Reviewed-by: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Tony Luck &lt;tony.luck@intel.com&gt;
Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1701310936080.3457@nanos
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;

</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?h=nds-private-remove&amp;id=0becc0ae5b42828785b589f686725ff5bc3b9b25'>Diffstat</a> (limited to 'kernel/trace/trace_hwlat.c')</div><table summary='diffstat' class='diffstat'>