/*
  File: linux/ext2_xattr.h

  On-disk format of extended attributes for the ext2 filesystem.

  (C) 2001 Andreas Gruenbacher, <a.gruenbacher@computer.org>
*/

#include <linux/init.h>
#include <linux/xattr.h>

/* Magic value in attribute blocks */
#define EXT2_XATTR_MAGIC		0xEA020000

/* Maximum number of references to one attribute block */
#define EXT2_XATTR_REFCOUNT_MAX		1024

/* Name indexes */
#define EXT2_XATTR_INDEX_USER			1
#define EXT2_XATTR_INDEX_POSIX_ACL_ACCESS	2
#define EXT2_XATTR_INDEX_POSIX_ACL_DEFAULT	3
#define EXT2_XATTR_INDEX_TRUSTED		4
#define	EXT2_XATTR_INDEX_LUSTRE			5
#define EXT2_XATTR_INDEX_SECURITY	        6

struct ext2_xattr_header {
	__le32	h_magic;	/* magic number for identification */
	__le32	h_refcount;	/* reference count */
	__le32	h_blocks;	/* number of disk blocks used */
	__le32	h_hash;		/* hash value of all attributes */
	__u32	h_reserved[4];	/* zero right now */
};

struct ext2_xattr_entry {
	__u8	e_name_len;	/* length of name */
	__u8	e_name_index;	/* attribute name index */
	__le16	e_value_offs;	/* offset in disk block of value */
	__le32	e_value_block;	/* disk block attribute is stored on (n/i) */
	__le32	e_value_size;	/* size of attribute value */
	__le32	e_hash;		/* hash value of name and value */
	char	e_name[0];	/* attribute name */
};

#define EXT2_XATTR_PAD_BITS		2
#define EXT2_XATTR_PAD		(1<<EXT2_XATTR_PAD_BITS)
#define EXT2_XATTR_ROUND		(EXT2_XATTR_PAD-1)
#define EXT2_XATTR_LEN(name_len) \
	(((name_len) + EXT2_XATTR_ROUND + \
	sizeof(struct ext2_xattr_entry)) & ~EXT2_XATTR_ROUND)
#define EXT2_XATTR_NEXT(entry) \
	( (struct ext2_xattr_entry *)( \
	  (char *)(entry) + EXT2_XATTR_LEN((entry)->e_name_len)) )
#define EXT2_XATTR_SIZE(size) \
	(((size) + EXT2_XATTR_ROUND) & ~EXT2_XATTR_ROUND)

struct mb_cache;

# ifdef CONFIG_EXT2_FS_XATTR

extern const struct xattr_handler ext2_xattr_user_handler;
extern const struct xattr_handler ext2_xattr_trusted_handler;
extern const struct xattr_handler ext2_xattr_security_handler;

extern ssize_t ext2_listxattr(struct dentry *, char *, size_t);

extern int ext2_xattr_get(struct inode *, int, const char *, void *, size_t);
extern int ext2_xattr_set(struct inode *, int, const char *, const void *, size_t, int);

extern void ext2_xattr_delete_inode(struct inode *);

extern struct mb_cache *ext2_xattr_create_cache(void);
extern void ext2_xattr_destroy_cache(struct mb_cache *cache);

extern const struct xattr_handler *ext2_xattr_handlers[];

# else  /* CONFIG_EXT2_FS_XATTR */

static inline int
ext2_xattr_get(struct inode *inode, int name_index,
	       const char *name, void *buffer, size_t size)
{
	return -EOPNOTSUPP;
}

static inline int
ext2_xattr_set(struct inode *inode, int name_index, const char *name,
	       const void *value, size_t size, int flags)
{
	return -EOPNOTSUPP;
}

static inline void
ext2_xattr_delete_inode(struct inode *inode)
{
}

static inline void ext2_xattr_destroy_cache(struct mb_cache *cache)
{
}

#define ext2_xattr_handlers NULL

# endif  /* CONFIG_EXT2_FS_XATTR */

#ifdef CONFIG_EXT2_FS_SECURITY
extern int ext2_init_security(struct inode *inode, struct inode *dir,
			      const struct qstr *qstr);
#else
static inline int ext2_init_security(struct inode *inode, struct inode *dir,
				     const struct qstr *qstr)
{
	return 0;
}
#endif
an='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/include/target/iscsi?id=c8f325a59cfc718d13a50fbc746ed9b415c25e92'>c8f325a59cfc718d13a50fbc746ed9b415c25e92</a> (<a href='/cgit.cgi/linux/net-next.git/patch/include/target/iscsi?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/target/iscsi?id=c8f325a59cfc718d13a50fbc746ed9b415c25e92'>include/target/iscsi</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/include/target/iscsi?id=bf29bddf0417a4783da3b24e8c9e017ac649326f'>bf29bddf0417a4783da3b24e8c9e017ac649326f</a> (<a href='/cgit.cgi/linux/net-next.git/diff/include/target/iscsi?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/target/iscsi')</div><table summary='diffstat' class='diffstat'>