kernel_optimize_test/fs/xfs/xfs_inode.h
Dave Chinner 653c60b633 xfs: introduce mmap/truncate lock
Right now we cannot serialise mmap against truncate or hole punch
sanely. ->page_mkwrite is not able to take locks that the read IO
path normally takes (i.e. the inode iolock) because that could
result in lock inversions (read - iolock - page fault - page_mkwrite
- iolock) and so we cannot use an IO path lock to serialise page
write faults against truncate operations.

Instead, introduce a new lock that is used *only* in the
->page_mkwrite path that is the equivalent of the iolock. The lock
ordering in a page fault is i_mmaplock -> page lock -> i_ilock,
and so in truncate we can i_iolock -> i_mmaplock and so lock out
new write faults during the process of truncation.

Because i_mmap_lock is outside the page lock, we can hold it across
all the same operations we hold the i_iolock for. The only
difference is that we never hold the i_mmaplock in the normal IO
path and so do not ever have the possibility that we can page fault
inside it. Hence there are no recursion issues on the i_mmap_lock
and so we can use it to serialise page fault IO against inode
modification operations that affect the IO path.

This patch introduces the i_mmaplock infrastructure, lockdep
annotations and initialisation/destruction code. Use of the new lock
will be in subsequent patches.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-02-23 21:43:37 +11:00

434 lines
13 KiB
C

/*
* Copyright (c) 2000-2003,2005 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_INODE_H__
#define __XFS_INODE_H__
#include "xfs_inode_buf.h"
#include "xfs_inode_fork.h"
/*
* Kernel only inode definitions
*/
struct xfs_dinode;
struct xfs_inode;
struct xfs_buf;
struct xfs_bmap_free;
struct xfs_bmbt_irec;
struct xfs_inode_log_item;
struct xfs_mount;
struct xfs_trans;
struct xfs_dquot;
typedef struct xfs_inode {
/* Inode linking and identification information. */
struct xfs_mount *i_mount; /* fs mount struct ptr */
struct xfs_dquot *i_udquot; /* user dquot */
struct xfs_dquot *i_gdquot; /* group dquot */
struct xfs_dquot *i_pdquot; /* project dquot */
/* Inode location stuff */
xfs_ino_t i_ino; /* inode number (agno/agino)*/
struct xfs_imap i_imap; /* location for xfs_imap() */
/* Extent information. */
xfs_ifork_t *i_afp; /* attribute fork pointer */
xfs_ifork_t i_df; /* data fork */
/* operations vectors */
const struct xfs_dir_ops *d_ops; /* directory ops vector */
/* Transaction and locking information. */
struct xfs_inode_log_item *i_itemp; /* logging information */
mrlock_t i_lock; /* inode lock */
mrlock_t i_iolock; /* inode IO lock */
mrlock_t i_mmaplock; /* inode mmap IO lock */
atomic_t i_pincount; /* inode pin count */
spinlock_t i_flags_lock; /* inode i_flags lock */
/* Miscellaneous state. */
unsigned long i_flags; /* see defined flags below */
unsigned int i_delayed_blks; /* count of delay alloc blks */
xfs_icdinode_t i_d; /* most of ondisk inode */
/* VFS inode */
struct inode i_vnode; /* embedded VFS inode */
} xfs_inode_t;
/* Convert from vfs inode to xfs inode */
static inline struct xfs_inode *XFS_I(struct inode *inode)
{
return container_of(inode, struct xfs_inode, i_vnode);
}
/* convert from xfs inode to vfs inode */
static inline struct inode *VFS_I(struct xfs_inode *ip)
{
return &ip->i_vnode;
}
/*
* For regular files we only update the on-disk filesize when actually
* writing data back to disk. Until then only the copy in the VFS inode
* is uptodate.
*/
static inline xfs_fsize_t XFS_ISIZE(struct xfs_inode *ip)
{
if (S_ISREG(ip->i_d.di_mode))
return i_size_read(VFS_I(ip));
return ip->i_d.di_size;
}
/*
* If this I/O goes past the on-disk inode size update it unless it would
* be past the current in-core inode size.
*/
static inline xfs_fsize_t
xfs_new_eof(struct xfs_inode *ip, xfs_fsize_t new_size)
{
xfs_fsize_t i_size = i_size_read(VFS_I(ip));
if (new_size > i_size || new_size < 0)
new_size = i_size;
return new_size > ip->i_d.di_size ? new_size : 0;
}
/*
* i_flags helper functions
*/
static inline void
__xfs_iflags_set(xfs_inode_t *ip, unsigned short flags)
{
ip->i_flags |= flags;
}
static inline void
xfs_iflags_set(xfs_inode_t *ip, unsigned short flags)
{
spin_lock(&ip->i_flags_lock);
__xfs_iflags_set(ip, flags);
spin_unlock(&ip->i_flags_lock);
}
static inline void
xfs_iflags_clear(xfs_inode_t *ip, unsigned short flags)
{
spin_lock(&ip->i_flags_lock);
ip->i_flags &= ~flags;
spin_unlock(&ip->i_flags_lock);
}
static inline int
__xfs_iflags_test(xfs_inode_t *ip, unsigned short flags)
{
return (ip->i_flags & flags);
}
static inline int
xfs_iflags_test(xfs_inode_t *ip, unsigned short flags)
{
int ret;
spin_lock(&ip->i_flags_lock);
ret = __xfs_iflags_test(ip, flags);
spin_unlock(&ip->i_flags_lock);
return ret;
}
static inline int
xfs_iflags_test_and_clear(xfs_inode_t *ip, unsigned short flags)
{
int ret;
spin_lock(&ip->i_flags_lock);
ret = ip->i_flags & flags;
if (ret)
ip->i_flags &= ~flags;
spin_unlock(&ip->i_flags_lock);
return ret;
}
static inline int
xfs_iflags_test_and_set(xfs_inode_t *ip, unsigned short flags)
{
int ret;
spin_lock(&ip->i_flags_lock);
ret = ip->i_flags & flags;
if (!ret)
ip->i_flags |= flags;
spin_unlock(&ip->i_flags_lock);
return ret;
}
/*
* Project quota id helpers (previously projid was 16bit only
* and using two 16bit values to hold new 32bit projid was chosen
* to retain compatibility with "old" filesystems).
*/
static inline prid_t
xfs_get_projid(struct xfs_inode *ip)
{
return (prid_t)ip->i_d.di_projid_hi << 16 | ip->i_d.di_projid_lo;
}
static inline void
xfs_set_projid(struct xfs_inode *ip,
prid_t projid)
{
ip->i_d.di_projid_hi = (__uint16_t) (projid >> 16);
ip->i_d.di_projid_lo = (__uint16_t) (projid & 0xffff);
}
static inline prid_t
xfs_get_initial_prid(struct xfs_inode *dp)
{
if (dp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT)
return xfs_get_projid(dp);
return XFS_PROJID_DEFAULT;
}
/*
* In-core inode flags.
*/
#define XFS_IRECLAIM (1 << 0) /* started reclaiming this inode */
#define XFS_ISTALE (1 << 1) /* inode has been staled */
#define XFS_IRECLAIMABLE (1 << 2) /* inode can be reclaimed */
#define XFS_INEW (1 << 3) /* inode has just been allocated */
#define XFS_ITRUNCATED (1 << 5) /* truncated down so flush-on-close */
#define XFS_IDIRTY_RELEASE (1 << 6) /* dirty release already seen */
#define __XFS_IFLOCK_BIT 7 /* inode is being flushed right now */
#define XFS_IFLOCK (1 << __XFS_IFLOCK_BIT)
#define __XFS_IPINNED_BIT 8 /* wakeup key for zero pin count */
#define XFS_IPINNED (1 << __XFS_IPINNED_BIT)
#define XFS_IDONTCACHE (1 << 9) /* don't cache the inode long term */
/*
* Per-lifetime flags need to be reset when re-using a reclaimable inode during
* inode lookup. This prevents unintended behaviour on the new inode from
* ocurring.
*/
#define XFS_IRECLAIM_RESET_FLAGS \
(XFS_IRECLAIMABLE | XFS_IRECLAIM | \
XFS_IDIRTY_RELEASE | XFS_ITRUNCATED)
/*
* Synchronize processes attempting to flush the in-core inode back to disk.
*/
extern void __xfs_iflock(struct xfs_inode *ip);
static inline int xfs_iflock_nowait(struct xfs_inode *ip)
{
return !xfs_iflags_test_and_set(ip, XFS_IFLOCK);
}
static inline void xfs_iflock(struct xfs_inode *ip)
{
if (!xfs_iflock_nowait(ip))
__xfs_iflock(ip);
}
static inline void xfs_ifunlock(struct xfs_inode *ip)
{
xfs_iflags_clear(ip, XFS_IFLOCK);
smp_mb();
wake_up_bit(&ip->i_flags, __XFS_IFLOCK_BIT);
}
static inline int xfs_isiflocked(struct xfs_inode *ip)
{
return xfs_iflags_test(ip, XFS_IFLOCK);
}
/*
* Flags for inode locking.
* Bit ranges: 1<<1 - 1<<16-1 -- iolock/ilock modes (bitfield)
* 1<<16 - 1<<32-1 -- lockdep annotation (integers)
*/
#define XFS_IOLOCK_EXCL (1<<0)
#define XFS_IOLOCK_SHARED (1<<1)
#define XFS_ILOCK_EXCL (1<<2)
#define XFS_ILOCK_SHARED (1<<3)
#define XFS_MMAPLOCK_EXCL (1<<4)
#define XFS_MMAPLOCK_SHARED (1<<5)
#define XFS_LOCK_MASK (XFS_IOLOCK_EXCL | XFS_IOLOCK_SHARED \
| XFS_ILOCK_EXCL | XFS_ILOCK_SHARED \
| XFS_MMAPLOCK_EXCL | XFS_MMAPLOCK_SHARED)
#define XFS_LOCK_FLAGS \
{ XFS_IOLOCK_EXCL, "IOLOCK_EXCL" }, \
{ XFS_IOLOCK_SHARED, "IOLOCK_SHARED" }, \
{ XFS_ILOCK_EXCL, "ILOCK_EXCL" }, \
{ XFS_ILOCK_SHARED, "ILOCK_SHARED" }, \
{ XFS_MMAPLOCK_EXCL, "MMAPLOCK_EXCL" }, \
{ XFS_MMAPLOCK_SHARED, "MMAPLOCK_SHARED" }
/*
* Flags for lockdep annotations.
*
* XFS_LOCK_PARENT - for directory operations that require locking a
* parent directory inode and a child entry inode. The parent gets locked
* with this flag so it gets a lockdep subclass of 1 and the child entry
* lock will have a lockdep subclass of 0.
*
* XFS_LOCK_RTBITMAP/XFS_LOCK_RTSUM - the realtime device bitmap and summary
* inodes do not participate in the normal lock order, and thus have their
* own subclasses.
*
* XFS_LOCK_INUMORDER - for locking several inodes at the some time
* with xfs_lock_inodes(). This flag is used as the starting subclass
* and each subsequent lock acquired will increment the subclass by one.
* So the first lock acquired will have a lockdep subclass of 4, the
* second lock will have a lockdep subclass of 5, and so on. It is
* the responsibility of the class builder to shift this to the correct
* portion of the lock_mode lockdep mask.
*/
#define XFS_LOCK_PARENT 1
#define XFS_LOCK_RTBITMAP 2
#define XFS_LOCK_RTSUM 3
#define XFS_LOCK_INUMORDER 4
#define XFS_IOLOCK_SHIFT 16
#define XFS_IOLOCK_PARENT (XFS_LOCK_PARENT << XFS_IOLOCK_SHIFT)
#define XFS_MMAPLOCK_SHIFT 20
#define XFS_ILOCK_SHIFT 24
#define XFS_ILOCK_PARENT (XFS_LOCK_PARENT << XFS_ILOCK_SHIFT)
#define XFS_ILOCK_RTBITMAP (XFS_LOCK_RTBITMAP << XFS_ILOCK_SHIFT)
#define XFS_ILOCK_RTSUM (XFS_LOCK_RTSUM << XFS_ILOCK_SHIFT)
#define XFS_IOLOCK_DEP_MASK 0x000f0000
#define XFS_MMAPLOCK_DEP_MASK 0x00f00000
#define XFS_ILOCK_DEP_MASK 0xff000000
#define XFS_LOCK_DEP_MASK (XFS_IOLOCK_DEP_MASK | \
XFS_MMAPLOCK_DEP_MASK | \
XFS_ILOCK_DEP_MASK)
#define XFS_IOLOCK_DEP(flags) (((flags) & XFS_IOLOCK_DEP_MASK) \
>> XFS_IOLOCK_SHIFT)
#define XFS_MMAPLOCK_DEP(flags) (((flags) & XFS_MMAPLOCK_DEP_MASK) \
>> XFS_MMAPLOCK_SHIFT)
#define XFS_ILOCK_DEP(flags) (((flags) & XFS_ILOCK_DEP_MASK) \
>> XFS_ILOCK_SHIFT)
/*
* For multiple groups support: if S_ISGID bit is set in the parent
* directory, group of new file is set to that of the parent, and
* new subdirectory gets S_ISGID bit from parent.
*/
#define XFS_INHERIT_GID(pip) \
(((pip)->i_mount->m_flags & XFS_MOUNT_GRPID) || \
((pip)->i_d.di_mode & S_ISGID))
int xfs_release(struct xfs_inode *ip);
void xfs_inactive(struct xfs_inode *ip);
int xfs_lookup(struct xfs_inode *dp, struct xfs_name *name,
struct xfs_inode **ipp, struct xfs_name *ci_name);
int xfs_create(struct xfs_inode *dp, struct xfs_name *name,
umode_t mode, xfs_dev_t rdev, struct xfs_inode **ipp);
int xfs_create_tmpfile(struct xfs_inode *dp, struct dentry *dentry,
umode_t mode, struct xfs_inode **ipp);
int xfs_remove(struct xfs_inode *dp, struct xfs_name *name,
struct xfs_inode *ip);
int xfs_link(struct xfs_inode *tdp, struct xfs_inode *sip,
struct xfs_name *target_name);
int xfs_rename(struct xfs_inode *src_dp, struct xfs_name *src_name,
struct xfs_inode *src_ip, struct xfs_inode *target_dp,
struct xfs_name *target_name,
struct xfs_inode *target_ip, unsigned int flags);
void xfs_ilock(xfs_inode_t *, uint);
int xfs_ilock_nowait(xfs_inode_t *, uint);
void xfs_iunlock(xfs_inode_t *, uint);
void xfs_ilock_demote(xfs_inode_t *, uint);
int xfs_isilocked(xfs_inode_t *, uint);
uint xfs_ilock_data_map_shared(struct xfs_inode *);
uint xfs_ilock_attr_map_shared(struct xfs_inode *);
int xfs_ialloc(struct xfs_trans *, xfs_inode_t *, umode_t,
xfs_nlink_t, xfs_dev_t, prid_t, int,
struct xfs_buf **, xfs_inode_t **);
uint xfs_ip2xflags(struct xfs_inode *);
uint xfs_dic2xflags(struct xfs_dinode *);
int xfs_ifree(struct xfs_trans *, xfs_inode_t *,
struct xfs_bmap_free *);
int xfs_itruncate_extents(struct xfs_trans **, struct xfs_inode *,
int, xfs_fsize_t);
int xfs_iunlink(struct xfs_trans *, xfs_inode_t *);
void xfs_iext_realloc(xfs_inode_t *, int, int);
void xfs_iunpin_wait(xfs_inode_t *);
#define xfs_ipincount(ip) ((unsigned int) atomic_read(&ip->i_pincount))
int xfs_iflush(struct xfs_inode *, struct xfs_buf **);
void xfs_lock_inodes(xfs_inode_t **, int, uint);
void xfs_lock_two_inodes(xfs_inode_t *, xfs_inode_t *, uint);
xfs_extlen_t xfs_get_extsz_hint(struct xfs_inode *ip);
int xfs_dir_ialloc(struct xfs_trans **, struct xfs_inode *, umode_t,
xfs_nlink_t, xfs_dev_t, prid_t, int,
struct xfs_inode **, int *);
int xfs_droplink(struct xfs_trans *, struct xfs_inode *);
int xfs_bumplink(struct xfs_trans *, struct xfs_inode *);
/* from xfs_file.c */
enum xfs_prealloc_flags {
XFS_PREALLOC_SET = (1 << 1),
XFS_PREALLOC_CLEAR = (1 << 2),
XFS_PREALLOC_SYNC = (1 << 3),
XFS_PREALLOC_INVISIBLE = (1 << 4),
};
int xfs_update_prealloc_flags(struct xfs_inode *,
enum xfs_prealloc_flags);
int xfs_zero_eof(struct xfs_inode *, xfs_off_t, xfs_fsize_t);
int xfs_iozero(struct xfs_inode *, loff_t, size_t);
#define IHOLD(ip) \
do { \
ASSERT(atomic_read(&VFS_I(ip)->i_count) > 0) ; \
ihold(VFS_I(ip)); \
trace_xfs_ihold(ip, _THIS_IP_); \
} while (0)
#define IRELE(ip) \
do { \
trace_xfs_irele(ip, _THIS_IP_); \
iput(VFS_I(ip)); \
} while (0)
extern struct kmem_zone *xfs_inode_zone;
/*
* Flags for read/write calls
*/
#define XFS_IO_ISDIRECT 0x00001 /* bypass page cache */
#define XFS_IO_INVIS 0x00002 /* don't update inode timestamps */
#define XFS_IO_FLAGS \
{ XFS_IO_ISDIRECT, "DIRECT" }, \
{ XFS_IO_INVIS, "INVIS"}
#endif /* __XFS_INODE_H__ */