/*
* Copyright (c) 2000,2002-2003,2005 Silicon Graphics, Inc.
* All Rights Reserved.
*
* This program 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.
*
* This program is distributed in the hope that it would 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; if not, write the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef __XFS_ATTR_H__
#define __XFS_ATTR_H__
struct xfs_inode;
struct xfs_da_args;
struct xfs_attr_list_context;
/*
* Large attribute lists are structured around Btrees where all the data
* elements are in the leaf nodes. Attribute names are hashed into an int,
* then that int is used as the index into the Btree. Since the hashval
* of an attribute name may not be unique, we may have duplicate keys.
* The internal links in the Btree are logical block offsets into the file.
*
* Small attribute lists use a different format and are packed as tightly
* as possible so as to fit into the literal area of the inode.
*/
/*========================================================================
* External interfaces
*========================================================================*/
#define ATTR_DONTFOLLOW 0x0001 /* -- unused, from IRIX -- */
#define ATTR_ROOT 0x0002 /* use attrs in root (trusted) namespace */
#define ATTR_TRUST 0x0004 /* -- unused, from IRIX -- */
#define ATTR_SECURE 0x0008 /* use attrs in security namespace */
#define ATTR_CREATE 0x0010 /* pure create: fail if attr already exists */
#define ATTR_REPLACE 0x0020 /* pure set: fail if attr does not exist */
#define ATTR_KERNOTIME 0x1000 /* [kernel] don't update inode timestamps */
#define ATTR_KERNOVAL 0x2000 /* [kernel] get attr size only, not value */
#define XFS_ATTR_FLAGS \
{ ATTR_DONTFOLLOW, "DONTFOLLOW" }, \
{ ATTR_ROOT, "ROOT" }, \
{ ATTR_TRUST, "TRUST" }, \
{ ATTR_SECURE, "SECURE" }, \
{ ATTR_CREATE, "CREATE" }, \
{ ATTR_REPLACE, "REPLACE" }, \
{ ATTR_KERNOTIME, "KERNOTIME" }, \
{ ATTR_KERNOVAL, "KERNOVAL" }
/*
* The maximum size (into the kernel or returned from the kernel) of an
* attribute value or the buffer used for an attr_list() call. Larger
* sizes will result in an ERANGE return code.
*/
#define ATTR_MAX_VALUELEN (64*1024) /* max length of a value */
/*
* Define how lists of attribute names are returned to the user from
* the attr_list() call. A large, 32bit aligned, buffer is passed in
* along with its size. We put an array of offsets at the top that each
* reference an attrlist_ent_t and pack the attrlist_ent_t's at the bottom.
*/
typedef struct attrlist {
__s32 al_count; /* number of entries in attrlist */
__s32 al_more; /* T/F: more attrs (do call again) */
__s32 al_offset[1]; /* byte offsets of attrs [var-sized] */
} attrlist_t;
/*
* Show the interesting info about one attribute. This is what the
* al_offset[i] entry points to.
*/
typedef struct attrlist_ent { /* data from attr_list() */
__u32 a_valuelen; /* number bytes in value of attr */
char a_name[1]; /* attr name (NULL terminated) */
} attrlist_ent_t;
/*
* Given a pointer to the (char*) buffer containing the attr_list() result,
* and an index, return a pointer to the indicated attribute in the buffer.
*/
#define ATTR_ENTRY(buffer, index) \
((attrlist_ent_t *) \
&((char *)buffer)[ ((attrlist_t *)(buffer))->al_offset[index] ])
/*
* Kernel-internal version of the attrlist cursor.
*/
typedef struct attrlist_cursor_kern {
__u32 hashval; /* hash value of next entry to add */
__u32 blkno; /* block containing entry (suggestion) */
__u32 offset; /* offset in list of equal-hashvals */
__u16 pad1; /* padding to match user-level */
__u8 pad2; /* padding to match user-level */
__u8 initted; /* T/F: cursor has been initialized */
} attrlist_cursor_kern_t;
/*========================================================================
* Structure used to pass context around among the routines.
*========================================================================*/
/* void; state communicated via *context */
typedef void (*put_listent_func_t)(struct xfs_attr_list_context *, int,
unsigned char *, int, int);
typedef struct xfs_attr_list_context {
struct xfs_inode *dp; /* inode */
struct attrlist_cursor_kern *cursor; /* position in list */
char *alist; /* output buffer */
int seen_enough; /* T/F: seen enough of list? */
ssize_t count; /* num used entries */
int dupcnt; /* count dup hashvals seen */
int bufsize; /* total buffer size */
int firstu; /* first used byte in buffer */
int flags; /* from VOP call */
int resynch; /* T/F: resynch with cursor */
put_listent_func_t put_listent; /* list output fmt function */
int index; /* index into output buffer */
} xfs_attr_list_context_t;
/*========================================================================
* Function prototypes for the kernel.
*========================================================================*/
/*
* Overall external interface routines.
*/
int xfs_attr_inactive(struct xfs_inode *dp);
int xfs_attr_list_int(struct xfs_attr_list_context *);
int xfs_inode_hasattr(struct xfs_inode *ip);
int xfs_attr_get(struct xfs_inode *ip, const unsigned char *name,
unsigned char *value, int *valuelenp, int flags);
int xfs_attr_set(struct xfs_inode *dp, const unsigned char *name,
unsigned char *value, int valuelen, int flags);
int xfs_attr_remove(struct xfs_inode *dp, const unsigned char *name, int flags);
int xfs_attr_list(struct xfs_inode *dp, char *buffer, int bufsize,
int flags, struct attrlist_cursor_kern *cursor);
#endif /* __XFS_ATTR_H__ */
imitives - this
optimizes paravirt performance. (Pan Xinhui, Juergen Gross,
Christian Borntraeger)
- Introduce cpu_relax_yield() and remov cpu_relax_lowlatency() to
clean up and improve the s390 lock yielding machinery and its core
kernel impact. (Christian Borntraeger)
- Micro-optimize mutexes some more. (Waiman Long)
- Reluctantly add the to-be-deprecated mutex_trylock_recursive()
interface on a temporary basis, to give the DRM code more time to
get rid of its locking hacks. Any other users will be NAK-ed on
sight. (We turned off the deprecation warning for the time being to
not pollute the build log.) (Peter Zijlstra)
- Improve the rtmutex code a bit, in light of recent long lived
bugs/races. (Thomas Gleixner)
- Misc fixes, cleanups"
* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits)
x86/paravirt: Fix bool return type for PVOP_CALL()
x86/paravirt: Fix native_patch()
locking/ww_mutex: Use relaxed atomics
locking/rtmutex: Explain locking rules for rt_mutex_proxy_unlock()/init_proxy_locked()
locking/rtmutex: Get rid of RT_MUTEX_OWNER_MASKALL
x86/paravirt: Optimize native pv_lock_ops.vcpu_is_preempted()
locking/mutex: Break out of expensive busy-loop on {mutex,rwsem}_spin_on_owner() when owner vCPU is preempted
locking/osq: Break out of spin-wait busy waiting loop for a preempted vCPU in osq_lock()
Documentation/virtual/kvm: Support the vCPU preemption check
x86/xen: Support the vCPU preemption check
x86/kvm: Support the vCPU preemption check
x86/kvm: Support the vCPU preemption check
kvm: Introduce kvm_write_guest_offset_cached()
locking/core, x86/paravirt: Implement vcpu_is_preempted(cpu) for KVM and Xen guests
locking/spinlocks, s390: Implement vcpu_is_preempted(cpu)
locking/core, powerpc: Implement vcpu_is_preempted(cpu)
sched/core: Introduce the vcpu_is_preempted(cpu) interface
sched/wake_q: Rename WAKE_Q to DEFINE_WAKE_Q
locking/core: Provide common cpu_relax_yield() definition
locking/mutex: Don't mark mutex_trylock_recursive() as deprecated, temporarily
...