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linux/fs/xfs/xfs_extfree_item.h
Dave Chinner b199c8a4ba xfs: Pull EFI/EFD handling out from under the AIL lock
EFI/EFD interactions are protected from races by the AIL lock. They
are the only type of log items that require the the AIL lock to
serialise internal state, so they need to be separated from the AIL
lock before we can do bulk insert operations on the AIL.

To acheive this, convert the counter of the number of extents in the
EFI to an atomic so it can be safely manipulated by EFD processing
without locks. Also, convert the EFI state flag manipulations to use
atomic bit operations so no locks are needed to record state
changes. Finally, use the state bits to determine when it is safe to
free the EFI and clean up the code to do this neatly.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-12-20 11:59:49 +11:00

162 lines
5.1 KiB
C

/*
* Copyright (c) 2000,2005 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_EXTFREE_ITEM_H__
#define __XFS_EXTFREE_ITEM_H__
struct xfs_mount;
struct kmem_zone;
typedef struct xfs_extent {
xfs_dfsbno_t ext_start;
xfs_extlen_t ext_len;
} xfs_extent_t;
/*
* Since an xfs_extent_t has types (start:64, len: 32)
* there are different alignments on 32 bit and 64 bit kernels.
* So we provide the different variants for use by a
* conversion routine.
*/
typedef struct xfs_extent_32 {
__uint64_t ext_start;
__uint32_t ext_len;
} __attribute__((packed)) xfs_extent_32_t;
typedef struct xfs_extent_64 {
__uint64_t ext_start;
__uint32_t ext_len;
__uint32_t ext_pad;
} xfs_extent_64_t;
/*
* This is the structure used to lay out an efi log item in the
* log. The efi_extents field is a variable size array whose
* size is given by efi_nextents.
*/
typedef struct xfs_efi_log_format {
__uint16_t efi_type; /* efi log item type */
__uint16_t efi_size; /* size of this item */
__uint32_t efi_nextents; /* # extents to free */
__uint64_t efi_id; /* efi identifier */
xfs_extent_t efi_extents[1]; /* array of extents to free */
} xfs_efi_log_format_t;
typedef struct xfs_efi_log_format_32 {
__uint16_t efi_type; /* efi log item type */
__uint16_t efi_size; /* size of this item */
__uint32_t efi_nextents; /* # extents to free */
__uint64_t efi_id; /* efi identifier */
xfs_extent_32_t efi_extents[1]; /* array of extents to free */
} __attribute__((packed)) xfs_efi_log_format_32_t;
typedef struct xfs_efi_log_format_64 {
__uint16_t efi_type; /* efi log item type */
__uint16_t efi_size; /* size of this item */
__uint32_t efi_nextents; /* # extents to free */
__uint64_t efi_id; /* efi identifier */
xfs_extent_64_t efi_extents[1]; /* array of extents to free */
} xfs_efi_log_format_64_t;
/*
* This is the structure used to lay out an efd log item in the
* log. The efd_extents array is a variable size array whose
* size is given by efd_nextents;
*/
typedef struct xfs_efd_log_format {
__uint16_t efd_type; /* efd log item type */
__uint16_t efd_size; /* size of this item */
__uint32_t efd_nextents; /* # of extents freed */
__uint64_t efd_efi_id; /* id of corresponding efi */
xfs_extent_t efd_extents[1]; /* array of extents freed */
} xfs_efd_log_format_t;
typedef struct xfs_efd_log_format_32 {
__uint16_t efd_type; /* efd log item type */
__uint16_t efd_size; /* size of this item */
__uint32_t efd_nextents; /* # of extents freed */
__uint64_t efd_efi_id; /* id of corresponding efi */
xfs_extent_32_t efd_extents[1]; /* array of extents freed */
} __attribute__((packed)) xfs_efd_log_format_32_t;
typedef struct xfs_efd_log_format_64 {
__uint16_t efd_type; /* efd log item type */
__uint16_t efd_size; /* size of this item */
__uint32_t efd_nextents; /* # of extents freed */
__uint64_t efd_efi_id; /* id of corresponding efi */
xfs_extent_64_t efd_extents[1]; /* array of extents freed */
} xfs_efd_log_format_64_t;
#ifdef __KERNEL__
/*
* Max number of extents in fast allocation path.
*/
#define XFS_EFI_MAX_FAST_EXTENTS 16
/*
* Define EFI flag bits. Manipulated by set/clear/test_bit operators.
*/
#define XFS_EFI_RECOVERED 1
#define XFS_EFI_COMMITTED 2
/*
* This is the "extent free intention" log item. It is used
* to log the fact that some extents need to be free. It is
* used in conjunction with the "extent free done" log item
* described below.
*/
typedef struct xfs_efi_log_item {
xfs_log_item_t efi_item;
atomic_t efi_next_extent;
unsigned long efi_flags; /* misc flags */
xfs_efi_log_format_t efi_format;
} xfs_efi_log_item_t;
/*
* This is the "extent free done" log item. It is used to log
* the fact that some extents earlier mentioned in an efi item
* have been freed.
*/
typedef struct xfs_efd_log_item {
xfs_log_item_t efd_item;
xfs_efi_log_item_t *efd_efip;
uint efd_next_extent;
xfs_efd_log_format_t efd_format;
} xfs_efd_log_item_t;
/*
* Max number of extents in fast allocation path.
*/
#define XFS_EFD_MAX_FAST_EXTENTS 16
extern struct kmem_zone *xfs_efi_zone;
extern struct kmem_zone *xfs_efd_zone;
xfs_efi_log_item_t *xfs_efi_init(struct xfs_mount *, uint);
xfs_efd_log_item_t *xfs_efd_init(struct xfs_mount *, xfs_efi_log_item_t *,
uint);
int xfs_efi_copy_format(xfs_log_iovec_t *buf,
xfs_efi_log_format_t *dst_efi_fmt);
void xfs_efi_item_free(xfs_efi_log_item_t *);
#endif /* __KERNEL__ */
#endif /* __XFS_EXTFREE_ITEM_H__ */