27496a8c67
- ->releasepage() annotated (s/int/gfp_t), instances updated - missing gfp_t in fs/* added - fixed misannotation from the original sweep caught by bitwise checks: XFS used __nocast both for gfp_t and for flags used by XFS allocator. The latter left with unsigned int __nocast; we might want to add a different type for those but for now let's leave them alone. That, BTW, is a case when __nocast use had been actively confusing - it had been used in the same code for two different and similar types, with no way to catch misuses. Switch of gfp_t to bitwise had caught that immediately... One tricky bit is left alone to be dealt with later - mapping->flags is a mix of gfp_t and error indications. Left alone for now. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
1098 lines
33 KiB
C
1098 lines
33 KiB
C
/*
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* linux/include/linux/jbd.h
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*
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* Written by Stephen C. Tweedie <sct@redhat.com>
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*
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* Copyright 1998-2000 Red Hat, Inc --- All Rights Reserved
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*
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* This file is part of the Linux kernel and is made available under
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* the terms of the GNU General Public License, version 2, or at your
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* option, any later version, incorporated herein by reference.
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*
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* Definitions for transaction data structures for the buffer cache
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* filesystem journaling support.
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*/
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#ifndef _LINUX_JBD_H
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#define _LINUX_JBD_H
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#if defined(CONFIG_JBD) || defined(CONFIG_JBD_MODULE) || !defined(__KERNEL__)
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/* Allow this file to be included directly into e2fsprogs */
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#ifndef __KERNEL__
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#include "jfs_compat.h"
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#define JFS_DEBUG
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#define jfs_debug jbd_debug
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#else
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#include <linux/buffer_head.h>
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#include <linux/journal-head.h>
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#include <linux/stddef.h>
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#include <linux/bit_spinlock.h>
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#include <asm/semaphore.h>
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#endif
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#define journal_oom_retry 1
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/*
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* Define JBD_PARANIOD_IOFAIL to cause a kernel BUG() if ext3 finds
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* certain classes of error which can occur due to failed IOs. Under
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* normal use we want ext3 to continue after such errors, because
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* hardware _can_ fail, but for debugging purposes when running tests on
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* known-good hardware we may want to trap these errors.
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*/
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#undef JBD_PARANOID_IOFAIL
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/*
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* The default maximum commit age, in seconds.
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*/
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#define JBD_DEFAULT_MAX_COMMIT_AGE 5
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#ifdef CONFIG_JBD_DEBUG
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/*
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* Define JBD_EXPENSIVE_CHECKING to enable more expensive internal
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* consistency checks. By default we don't do this unless
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* CONFIG_JBD_DEBUG is on.
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*/
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#define JBD_EXPENSIVE_CHECKING
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extern int journal_enable_debug;
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#define jbd_debug(n, f, a...) \
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do { \
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if ((n) <= journal_enable_debug) { \
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printk (KERN_DEBUG "(%s, %d): %s: ", \
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__FILE__, __LINE__, __FUNCTION__); \
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printk (f, ## a); \
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} \
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} while (0)
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#else
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#define jbd_debug(f, a...) /**/
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#endif
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extern void * __jbd_kmalloc (const char *where, size_t size, gfp_t flags, int retry);
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#define jbd_kmalloc(size, flags) \
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__jbd_kmalloc(__FUNCTION__, (size), (flags), journal_oom_retry)
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#define jbd_rep_kmalloc(size, flags) \
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__jbd_kmalloc(__FUNCTION__, (size), (flags), 1)
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#define JFS_MIN_JOURNAL_BLOCKS 1024
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#ifdef __KERNEL__
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/**
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* typedef handle_t - The handle_t type represents a single atomic update being performed by some process.
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*
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* All filesystem modifications made by the process go
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* through this handle. Recursive operations (such as quota operations)
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* are gathered into a single update.
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*
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* The buffer credits field is used to account for journaled buffers
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* being modified by the running process. To ensure that there is
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* enough log space for all outstanding operations, we need to limit the
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* number of outstanding buffers possible at any time. When the
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* operation completes, any buffer credits not used are credited back to
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* the transaction, so that at all times we know how many buffers the
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* outstanding updates on a transaction might possibly touch.
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*
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* This is an opaque datatype.
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**/
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typedef struct handle_s handle_t; /* Atomic operation type */
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/**
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* typedef journal_t - The journal_t maintains all of the journaling state information for a single filesystem.
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*
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* journal_t is linked to from the fs superblock structure.
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*
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* We use the journal_t to keep track of all outstanding transaction
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* activity on the filesystem, and to manage the state of the log
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* writing process.
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*
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* This is an opaque datatype.
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**/
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typedef struct journal_s journal_t; /* Journal control structure */
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#endif
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/*
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* Internal structures used by the logging mechanism:
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*/
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#define JFS_MAGIC_NUMBER 0xc03b3998U /* The first 4 bytes of /dev/random! */
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/*
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* On-disk structures
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*/
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/*
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* Descriptor block types:
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*/
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#define JFS_DESCRIPTOR_BLOCK 1
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#define JFS_COMMIT_BLOCK 2
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#define JFS_SUPERBLOCK_V1 3
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#define JFS_SUPERBLOCK_V2 4
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#define JFS_REVOKE_BLOCK 5
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/*
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* Standard header for all descriptor blocks:
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*/
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typedef struct journal_header_s
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{
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__be32 h_magic;
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__be32 h_blocktype;
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__be32 h_sequence;
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} journal_header_t;
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/*
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* The block tag: used to describe a single buffer in the journal
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*/
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typedef struct journal_block_tag_s
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{
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__be32 t_blocknr; /* The on-disk block number */
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__be32 t_flags; /* See below */
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} journal_block_tag_t;
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/*
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* The revoke descriptor: used on disk to describe a series of blocks to
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* be revoked from the log
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*/
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typedef struct journal_revoke_header_s
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{
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journal_header_t r_header;
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__be32 r_count; /* Count of bytes used in the block */
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} journal_revoke_header_t;
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/* Definitions for the journal tag flags word: */
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#define JFS_FLAG_ESCAPE 1 /* on-disk block is escaped */
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#define JFS_FLAG_SAME_UUID 2 /* block has same uuid as previous */
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#define JFS_FLAG_DELETED 4 /* block deleted by this transaction */
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#define JFS_FLAG_LAST_TAG 8 /* last tag in this descriptor block */
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/*
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* The journal superblock. All fields are in big-endian byte order.
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*/
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typedef struct journal_superblock_s
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{
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/* 0x0000 */
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journal_header_t s_header;
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/* 0x000C */
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/* Static information describing the journal */
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__be32 s_blocksize; /* journal device blocksize */
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__be32 s_maxlen; /* total blocks in journal file */
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__be32 s_first; /* first block of log information */
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/* 0x0018 */
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/* Dynamic information describing the current state of the log */
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__be32 s_sequence; /* first commit ID expected in log */
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__be32 s_start; /* blocknr of start of log */
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/* 0x0020 */
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/* Error value, as set by journal_abort(). */
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__be32 s_errno;
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/* 0x0024 */
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/* Remaining fields are only valid in a version-2 superblock */
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__be32 s_feature_compat; /* compatible feature set */
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__be32 s_feature_incompat; /* incompatible feature set */
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__be32 s_feature_ro_compat; /* readonly-compatible feature set */
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/* 0x0030 */
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__u8 s_uuid[16]; /* 128-bit uuid for journal */
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/* 0x0040 */
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__be32 s_nr_users; /* Nr of filesystems sharing log */
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__be32 s_dynsuper; /* Blocknr of dynamic superblock copy*/
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/* 0x0048 */
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__be32 s_max_transaction; /* Limit of journal blocks per trans.*/
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__be32 s_max_trans_data; /* Limit of data blocks per trans. */
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/* 0x0050 */
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__u32 s_padding[44];
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/* 0x0100 */
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__u8 s_users[16*48]; /* ids of all fs'es sharing the log */
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/* 0x0400 */
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} journal_superblock_t;
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#define JFS_HAS_COMPAT_FEATURE(j,mask) \
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((j)->j_format_version >= 2 && \
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((j)->j_superblock->s_feature_compat & cpu_to_be32((mask))))
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#define JFS_HAS_RO_COMPAT_FEATURE(j,mask) \
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((j)->j_format_version >= 2 && \
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((j)->j_superblock->s_feature_ro_compat & cpu_to_be32((mask))))
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#define JFS_HAS_INCOMPAT_FEATURE(j,mask) \
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((j)->j_format_version >= 2 && \
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((j)->j_superblock->s_feature_incompat & cpu_to_be32((mask))))
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#define JFS_FEATURE_INCOMPAT_REVOKE 0x00000001
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/* Features known to this kernel version: */
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#define JFS_KNOWN_COMPAT_FEATURES 0
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#define JFS_KNOWN_ROCOMPAT_FEATURES 0
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#define JFS_KNOWN_INCOMPAT_FEATURES JFS_FEATURE_INCOMPAT_REVOKE
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#ifdef __KERNEL__
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#include <linux/fs.h>
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#include <linux/sched.h>
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#include <asm/bug.h>
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#define JBD_ASSERTIONS
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#ifdef JBD_ASSERTIONS
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#define J_ASSERT(assert) \
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do { \
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if (!(assert)) { \
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printk (KERN_EMERG \
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"Assertion failure in %s() at %s:%d: \"%s\"\n", \
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__FUNCTION__, __FILE__, __LINE__, # assert); \
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BUG(); \
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} \
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} while (0)
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#if defined(CONFIG_BUFFER_DEBUG)
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void buffer_assertion_failure(struct buffer_head *bh);
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#define J_ASSERT_BH(bh, expr) \
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do { \
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if (!(expr)) \
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buffer_assertion_failure(bh); \
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J_ASSERT(expr); \
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} while (0)
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#define J_ASSERT_JH(jh, expr) J_ASSERT_BH(jh2bh(jh), expr)
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#else
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#define J_ASSERT_BH(bh, expr) J_ASSERT(expr)
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#define J_ASSERT_JH(jh, expr) J_ASSERT(expr)
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#endif
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#else
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#define J_ASSERT(assert) do { } while (0)
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#endif /* JBD_ASSERTIONS */
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#if defined(JBD_PARANOID_IOFAIL)
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#define J_EXPECT(expr, why...) J_ASSERT(expr)
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#define J_EXPECT_BH(bh, expr, why...) J_ASSERT_BH(bh, expr)
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#define J_EXPECT_JH(jh, expr, why...) J_ASSERT_JH(jh, expr)
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#else
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#define __journal_expect(expr, why...) \
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({ \
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int val = (expr); \
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if (!val) { \
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printk(KERN_ERR \
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"EXT3-fs unexpected failure: %s;\n",# expr); \
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printk(KERN_ERR why "\n"); \
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} \
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val; \
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})
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#define J_EXPECT(expr, why...) __journal_expect(expr, ## why)
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#define J_EXPECT_BH(bh, expr, why...) __journal_expect(expr, ## why)
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#define J_EXPECT_JH(jh, expr, why...) __journal_expect(expr, ## why)
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#endif
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enum jbd_state_bits {
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BH_JBD /* Has an attached ext3 journal_head */
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= BH_PrivateStart,
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BH_JWrite, /* Being written to log (@@@ DEBUGGING) */
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BH_Freed, /* Has been freed (truncated) */
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BH_Revoked, /* Has been revoked from the log */
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BH_RevokeValid, /* Revoked flag is valid */
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BH_JBDDirty, /* Is dirty but journaled */
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BH_State, /* Pins most journal_head state */
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BH_JournalHead, /* Pins bh->b_private and jh->b_bh */
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BH_Unshadow, /* Dummy bit, for BJ_Shadow wakeup filtering */
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};
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BUFFER_FNS(JBD, jbd)
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BUFFER_FNS(JWrite, jwrite)
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BUFFER_FNS(JBDDirty, jbddirty)
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TAS_BUFFER_FNS(JBDDirty, jbddirty)
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BUFFER_FNS(Revoked, revoked)
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TAS_BUFFER_FNS(Revoked, revoked)
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BUFFER_FNS(RevokeValid, revokevalid)
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TAS_BUFFER_FNS(RevokeValid, revokevalid)
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BUFFER_FNS(Freed, freed)
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static inline struct buffer_head *jh2bh(struct journal_head *jh)
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{
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return jh->b_bh;
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}
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static inline struct journal_head *bh2jh(struct buffer_head *bh)
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{
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return bh->b_private;
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}
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static inline void jbd_lock_bh_state(struct buffer_head *bh)
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{
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bit_spin_lock(BH_State, &bh->b_state);
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}
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static inline int jbd_trylock_bh_state(struct buffer_head *bh)
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{
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return bit_spin_trylock(BH_State, &bh->b_state);
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}
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static inline int jbd_is_locked_bh_state(struct buffer_head *bh)
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{
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return bit_spin_is_locked(BH_State, &bh->b_state);
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}
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static inline void jbd_unlock_bh_state(struct buffer_head *bh)
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{
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bit_spin_unlock(BH_State, &bh->b_state);
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}
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static inline void jbd_lock_bh_journal_head(struct buffer_head *bh)
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{
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bit_spin_lock(BH_JournalHead, &bh->b_state);
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}
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static inline void jbd_unlock_bh_journal_head(struct buffer_head *bh)
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{
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bit_spin_unlock(BH_JournalHead, &bh->b_state);
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}
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struct jbd_revoke_table_s;
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/**
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* struct handle_s - The handle_s type is the concrete type associated with
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* handle_t.
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* @h_transaction: Which compound transaction is this update a part of?
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* @h_buffer_credits: Number of remaining buffers we are allowed to dirty.
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* @h_ref: Reference count on this handle
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* @h_err: Field for caller's use to track errors through large fs operations
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* @h_sync: flag for sync-on-close
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* @h_jdata: flag to force data journaling
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* @h_aborted: flag indicating fatal error on handle
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**/
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/* Docbook can't yet cope with the bit fields, but will leave the documentation
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* in so it can be fixed later.
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*/
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struct handle_s
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{
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/* Which compound transaction is this update a part of? */
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transaction_t *h_transaction;
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/* Number of remaining buffers we are allowed to dirty: */
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int h_buffer_credits;
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/* Reference count on this handle */
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int h_ref;
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/* Field for caller's use to track errors through large fs */
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/* operations */
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int h_err;
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/* Flags [no locking] */
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unsigned int h_sync: 1; /* sync-on-close */
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unsigned int h_jdata: 1; /* force data journaling */
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unsigned int h_aborted: 1; /* fatal error on handle */
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};
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|
|
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/* The transaction_t type is the guts of the journaling mechanism. It
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* tracks a compound transaction through its various states:
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*
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* RUNNING: accepting new updates
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* LOCKED: Updates still running but we don't accept new ones
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* RUNDOWN: Updates are tidying up but have finished requesting
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* new buffers to modify (state not used for now)
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* FLUSH: All updates complete, but we are still writing to disk
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* COMMIT: All data on disk, writing commit record
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* FINISHED: We still have to keep the transaction for checkpointing.
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*
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* The transaction keeps track of all of the buffers modified by a
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* running transaction, and all of the buffers committed but not yet
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* flushed to home for finished transactions.
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*/
|
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/*
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* Lock ranking:
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*
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* j_list_lock
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* ->jbd_lock_bh_journal_head() (This is "innermost")
|
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*
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* j_state_lock
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* ->jbd_lock_bh_state()
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*
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* jbd_lock_bh_state()
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* ->j_list_lock
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*
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* j_state_lock
|
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* ->t_handle_lock
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*
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* j_state_lock
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* ->j_list_lock (journal_unmap_buffer)
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*
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*/
|
|
|
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struct transaction_s
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{
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/* Pointer to the journal for this transaction. [no locking] */
|
|
journal_t *t_journal;
|
|
|
|
/* Sequence number for this transaction [no locking] */
|
|
tid_t t_tid;
|
|
|
|
/*
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* Transaction's current state
|
|
* [no locking - only kjournald alters this]
|
|
* FIXME: needs barriers
|
|
* KLUDGE: [use j_state_lock]
|
|
*/
|
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enum {
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T_RUNNING,
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T_LOCKED,
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T_RUNDOWN,
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T_FLUSH,
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T_COMMIT,
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T_FINISHED
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} t_state;
|
|
|
|
/*
|
|
* Where in the log does this transaction's commit start? [no locking]
|
|
*/
|
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unsigned long t_log_start;
|
|
|
|
/* Number of buffers on the t_buffers list [j_list_lock] */
|
|
int t_nr_buffers;
|
|
|
|
/*
|
|
* Doubly-linked circular list of all buffers reserved but not yet
|
|
* modified by this transaction [j_list_lock]
|
|
*/
|
|
struct journal_head *t_reserved_list;
|
|
|
|
/*
|
|
* Doubly-linked circular list of all buffers under writeout during
|
|
* commit [j_list_lock]
|
|
*/
|
|
struct journal_head *t_locked_list;
|
|
|
|
/*
|
|
* Doubly-linked circular list of all metadata buffers owned by this
|
|
* transaction [j_list_lock]
|
|
*/
|
|
struct journal_head *t_buffers;
|
|
|
|
/*
|
|
* Doubly-linked circular list of all data buffers still to be
|
|
* flushed before this transaction can be committed [j_list_lock]
|
|
*/
|
|
struct journal_head *t_sync_datalist;
|
|
|
|
/*
|
|
* Doubly-linked circular list of all forget buffers (superseded
|
|
* buffers which we can un-checkpoint once this transaction commits)
|
|
* [j_list_lock]
|
|
*/
|
|
struct journal_head *t_forget;
|
|
|
|
/*
|
|
* Doubly-linked circular list of all buffers still to be flushed before
|
|
* this transaction can be checkpointed. [j_list_lock]
|
|
*/
|
|
struct journal_head *t_checkpoint_list;
|
|
|
|
/*
|
|
* Doubly-linked circular list of temporary buffers currently undergoing
|
|
* IO in the log [j_list_lock]
|
|
*/
|
|
struct journal_head *t_iobuf_list;
|
|
|
|
/*
|
|
* Doubly-linked circular list of metadata buffers being shadowed by log
|
|
* IO. The IO buffers on the iobuf list and the shadow buffers on this
|
|
* list match each other one for one at all times. [j_list_lock]
|
|
*/
|
|
struct journal_head *t_shadow_list;
|
|
|
|
/*
|
|
* Doubly-linked circular list of control buffers being written to the
|
|
* log. [j_list_lock]
|
|
*/
|
|
struct journal_head *t_log_list;
|
|
|
|
/*
|
|
* Protects info related to handles
|
|
*/
|
|
spinlock_t t_handle_lock;
|
|
|
|
/*
|
|
* Number of outstanding updates running on this transaction
|
|
* [t_handle_lock]
|
|
*/
|
|
int t_updates;
|
|
|
|
/*
|
|
* Number of buffers reserved for use by all handles in this transaction
|
|
* handle but not yet modified. [t_handle_lock]
|
|
*/
|
|
int t_outstanding_credits;
|
|
|
|
/*
|
|
* Forward and backward links for the circular list of all transactions
|
|
* awaiting checkpoint. [j_list_lock]
|
|
*/
|
|
transaction_t *t_cpnext, *t_cpprev;
|
|
|
|
/*
|
|
* When will the transaction expire (become due for commit), in jiffies?
|
|
* [no locking]
|
|
*/
|
|
unsigned long t_expires;
|
|
|
|
/*
|
|
* How many handles used this transaction? [t_handle_lock]
|
|
*/
|
|
int t_handle_count;
|
|
|
|
};
|
|
|
|
/**
|
|
* struct journal_s - The journal_s type is the concrete type associated with
|
|
* journal_t.
|
|
* @j_flags: General journaling state flags
|
|
* @j_errno: Is there an outstanding uncleared error on the journal (from a
|
|
* prior abort)?
|
|
* @j_sb_buffer: First part of superblock buffer
|
|
* @j_superblock: Second part of superblock buffer
|
|
* @j_format_version: Version of the superblock format
|
|
* @j_state_lock: Protect the various scalars in the journal
|
|
* @j_barrier_count: Number of processes waiting to create a barrier lock
|
|
* @j_barrier: The barrier lock itself
|
|
* @j_running_transaction: The current running transaction..
|
|
* @j_committing_transaction: the transaction we are pushing to disk
|
|
* @j_checkpoint_transactions: a linked circular list of all transactions
|
|
* waiting for checkpointing
|
|
* @j_wait_transaction_locked: Wait queue for waiting for a locked transaction
|
|
* to start committing, or for a barrier lock to be released
|
|
* @j_wait_logspace: Wait queue for waiting for checkpointing to complete
|
|
* @j_wait_done_commit: Wait queue for waiting for commit to complete
|
|
* @j_wait_checkpoint: Wait queue to trigger checkpointing
|
|
* @j_wait_commit: Wait queue to trigger commit
|
|
* @j_wait_updates: Wait queue to wait for updates to complete
|
|
* @j_checkpoint_sem: Semaphore for locking against concurrent checkpoints
|
|
* @j_head: Journal head - identifies the first unused block in the journal
|
|
* @j_tail: Journal tail - identifies the oldest still-used block in the
|
|
* journal.
|
|
* @j_free: Journal free - how many free blocks are there in the journal?
|
|
* @j_first: The block number of the first usable block
|
|
* @j_last: The block number one beyond the last usable block
|
|
* @j_dev: Device where we store the journal
|
|
* @j_blocksize: blocksize for the location where we store the journal.
|
|
* @j_blk_offset: starting block offset for into the device where we store the
|
|
* journal
|
|
* @j_fs_dev: Device which holds the client fs. For internal journal this will
|
|
* be equal to j_dev
|
|
* @j_maxlen: Total maximum capacity of the journal region on disk.
|
|
* @j_list_lock: Protects the buffer lists and internal buffer state.
|
|
* @j_inode: Optional inode where we store the journal. If present, all journal
|
|
* block numbers are mapped into this inode via bmap().
|
|
* @j_tail_sequence: Sequence number of the oldest transaction in the log
|
|
* @j_transaction_sequence: Sequence number of the next transaction to grant
|
|
* @j_commit_sequence: Sequence number of the most recently committed
|
|
* transaction
|
|
* @j_commit_request: Sequence number of the most recent transaction wanting
|
|
* commit
|
|
* @j_uuid: Uuid of client object.
|
|
* @j_task: Pointer to the current commit thread for this journal
|
|
* @j_max_transaction_buffers: Maximum number of metadata buffers to allow in a
|
|
* single compound commit transaction
|
|
* @j_commit_interval: What is the maximum transaction lifetime before we begin
|
|
* a commit?
|
|
* @j_commit_timer: The timer used to wakeup the commit thread
|
|
* @j_revoke_lock: Protect the revoke table
|
|
* @j_revoke: The revoke table - maintains the list of revoked blocks in the
|
|
* current transaction.
|
|
* @j_revoke_table: alternate revoke tables for j_revoke
|
|
* @j_private: An opaque pointer to fs-private information.
|
|
*/
|
|
|
|
struct journal_s
|
|
{
|
|
/* General journaling state flags [j_state_lock] */
|
|
unsigned long j_flags;
|
|
|
|
/*
|
|
* Is there an outstanding uncleared error on the journal (from a prior
|
|
* abort)? [j_state_lock]
|
|
*/
|
|
int j_errno;
|
|
|
|
/* The superblock buffer */
|
|
struct buffer_head *j_sb_buffer;
|
|
journal_superblock_t *j_superblock;
|
|
|
|
/* Version of the superblock format */
|
|
int j_format_version;
|
|
|
|
/*
|
|
* Protect the various scalars in the journal
|
|
*/
|
|
spinlock_t j_state_lock;
|
|
|
|
/*
|
|
* Number of processes waiting to create a barrier lock [j_state_lock]
|
|
*/
|
|
int j_barrier_count;
|
|
|
|
/* The barrier lock itself */
|
|
struct semaphore j_barrier;
|
|
|
|
/*
|
|
* Transactions: The current running transaction...
|
|
* [j_state_lock] [caller holding open handle]
|
|
*/
|
|
transaction_t *j_running_transaction;
|
|
|
|
/*
|
|
* the transaction we are pushing to disk
|
|
* [j_state_lock] [caller holding open handle]
|
|
*/
|
|
transaction_t *j_committing_transaction;
|
|
|
|
/*
|
|
* ... and a linked circular list of all transactions waiting for
|
|
* checkpointing. [j_list_lock]
|
|
*/
|
|
transaction_t *j_checkpoint_transactions;
|
|
|
|
/*
|
|
* Wait queue for waiting for a locked transaction to start committing,
|
|
* or for a barrier lock to be released
|
|
*/
|
|
wait_queue_head_t j_wait_transaction_locked;
|
|
|
|
/* Wait queue for waiting for checkpointing to complete */
|
|
wait_queue_head_t j_wait_logspace;
|
|
|
|
/* Wait queue for waiting for commit to complete */
|
|
wait_queue_head_t j_wait_done_commit;
|
|
|
|
/* Wait queue to trigger checkpointing */
|
|
wait_queue_head_t j_wait_checkpoint;
|
|
|
|
/* Wait queue to trigger commit */
|
|
wait_queue_head_t j_wait_commit;
|
|
|
|
/* Wait queue to wait for updates to complete */
|
|
wait_queue_head_t j_wait_updates;
|
|
|
|
/* Semaphore for locking against concurrent checkpoints */
|
|
struct semaphore j_checkpoint_sem;
|
|
|
|
/*
|
|
* Journal head: identifies the first unused block in the journal.
|
|
* [j_state_lock]
|
|
*/
|
|
unsigned long j_head;
|
|
|
|
/*
|
|
* Journal tail: identifies the oldest still-used block in the journal.
|
|
* [j_state_lock]
|
|
*/
|
|
unsigned long j_tail;
|
|
|
|
/*
|
|
* Journal free: how many free blocks are there in the journal?
|
|
* [j_state_lock]
|
|
*/
|
|
unsigned long j_free;
|
|
|
|
/*
|
|
* Journal start and end: the block numbers of the first usable block
|
|
* and one beyond the last usable block in the journal. [j_state_lock]
|
|
*/
|
|
unsigned long j_first;
|
|
unsigned long j_last;
|
|
|
|
/*
|
|
* Device, blocksize and starting block offset for the location where we
|
|
* store the journal.
|
|
*/
|
|
struct block_device *j_dev;
|
|
int j_blocksize;
|
|
unsigned int j_blk_offset;
|
|
|
|
/*
|
|
* Device which holds the client fs. For internal journal this will be
|
|
* equal to j_dev.
|
|
*/
|
|
struct block_device *j_fs_dev;
|
|
|
|
/* Total maximum capacity of the journal region on disk. */
|
|
unsigned int j_maxlen;
|
|
|
|
/*
|
|
* Protects the buffer lists and internal buffer state.
|
|
*/
|
|
spinlock_t j_list_lock;
|
|
|
|
/* Optional inode where we store the journal. If present, all */
|
|
/* journal block numbers are mapped into this inode via */
|
|
/* bmap(). */
|
|
struct inode *j_inode;
|
|
|
|
/*
|
|
* Sequence number of the oldest transaction in the log [j_state_lock]
|
|
*/
|
|
tid_t j_tail_sequence;
|
|
|
|
/*
|
|
* Sequence number of the next transaction to grant [j_state_lock]
|
|
*/
|
|
tid_t j_transaction_sequence;
|
|
|
|
/*
|
|
* Sequence number of the most recently committed transaction
|
|
* [j_state_lock].
|
|
*/
|
|
tid_t j_commit_sequence;
|
|
|
|
/*
|
|
* Sequence number of the most recent transaction wanting commit
|
|
* [j_state_lock]
|
|
*/
|
|
tid_t j_commit_request;
|
|
|
|
/*
|
|
* Journal uuid: identifies the object (filesystem, LVM volume etc)
|
|
* backed by this journal. This will eventually be replaced by an array
|
|
* of uuids, allowing us to index multiple devices within a single
|
|
* journal and to perform atomic updates across them.
|
|
*/
|
|
__u8 j_uuid[16];
|
|
|
|
/* Pointer to the current commit thread for this journal */
|
|
struct task_struct *j_task;
|
|
|
|
/*
|
|
* Maximum number of metadata buffers to allow in a single compound
|
|
* commit transaction
|
|
*/
|
|
int j_max_transaction_buffers;
|
|
|
|
/*
|
|
* What is the maximum transaction lifetime before we begin a commit?
|
|
*/
|
|
unsigned long j_commit_interval;
|
|
|
|
/* The timer used to wakeup the commit thread: */
|
|
struct timer_list *j_commit_timer;
|
|
|
|
/*
|
|
* The revoke table: maintains the list of revoked blocks in the
|
|
* current transaction. [j_revoke_lock]
|
|
*/
|
|
spinlock_t j_revoke_lock;
|
|
struct jbd_revoke_table_s *j_revoke;
|
|
struct jbd_revoke_table_s *j_revoke_table[2];
|
|
|
|
/*
|
|
* array of bhs for journal_commit_transaction
|
|
*/
|
|
struct buffer_head **j_wbuf;
|
|
int j_wbufsize;
|
|
|
|
/*
|
|
* An opaque pointer to fs-private information. ext3 puts its
|
|
* superblock pointer here
|
|
*/
|
|
void *j_private;
|
|
};
|
|
|
|
/*
|
|
* Journal flag definitions
|
|
*/
|
|
#define JFS_UNMOUNT 0x001 /* Journal thread is being destroyed */
|
|
#define JFS_ABORT 0x002 /* Journaling has been aborted for errors. */
|
|
#define JFS_ACK_ERR 0x004 /* The errno in the sb has been acked */
|
|
#define JFS_FLUSHED 0x008 /* The journal superblock has been flushed */
|
|
#define JFS_LOADED 0x010 /* The journal superblock has been loaded */
|
|
#define JFS_BARRIER 0x020 /* Use IDE barriers */
|
|
|
|
/*
|
|
* Function declarations for the journaling transaction and buffer
|
|
* management
|
|
*/
|
|
|
|
/* Filing buffers */
|
|
extern void __journal_temp_unlink_buffer(struct journal_head *jh);
|
|
extern void journal_unfile_buffer(journal_t *, struct journal_head *);
|
|
extern void __journal_unfile_buffer(struct journal_head *);
|
|
extern void __journal_refile_buffer(struct journal_head *);
|
|
extern void journal_refile_buffer(journal_t *, struct journal_head *);
|
|
extern void __journal_file_buffer(struct journal_head *, transaction_t *, int);
|
|
extern void __journal_free_buffer(struct journal_head *bh);
|
|
extern void journal_file_buffer(struct journal_head *, transaction_t *, int);
|
|
extern void __journal_clean_data_list(transaction_t *transaction);
|
|
|
|
/* Log buffer allocation */
|
|
extern struct journal_head * journal_get_descriptor_buffer(journal_t *);
|
|
int journal_next_log_block(journal_t *, unsigned long *);
|
|
|
|
/* Commit management */
|
|
extern void journal_commit_transaction(journal_t *);
|
|
|
|
/* Checkpoint list management */
|
|
int __journal_clean_checkpoint_list(journal_t *journal);
|
|
void __journal_remove_checkpoint(struct journal_head *);
|
|
void __journal_insert_checkpoint(struct journal_head *, transaction_t *);
|
|
|
|
/* Buffer IO */
|
|
extern int
|
|
journal_write_metadata_buffer(transaction_t *transaction,
|
|
struct journal_head *jh_in,
|
|
struct journal_head **jh_out,
|
|
int blocknr);
|
|
|
|
/* Transaction locking */
|
|
extern void __wait_on_journal (journal_t *);
|
|
|
|
/*
|
|
* Journal locking.
|
|
*
|
|
* We need to lock the journal during transaction state changes so that nobody
|
|
* ever tries to take a handle on the running transaction while we are in the
|
|
* middle of moving it to the commit phase. j_state_lock does this.
|
|
*
|
|
* Note that the locking is completely interrupt unsafe. We never touch
|
|
* journal structures from interrupts.
|
|
*/
|
|
|
|
static inline handle_t *journal_current_handle(void)
|
|
{
|
|
return current->journal_info;
|
|
}
|
|
|
|
/* The journaling code user interface:
|
|
*
|
|
* Create and destroy handles
|
|
* Register buffer modifications against the current transaction.
|
|
*/
|
|
|
|
extern handle_t *journal_start(journal_t *, int nblocks);
|
|
extern int journal_restart (handle_t *, int nblocks);
|
|
extern int journal_extend (handle_t *, int nblocks);
|
|
extern int journal_get_write_access(handle_t *, struct buffer_head *);
|
|
extern int journal_get_create_access (handle_t *, struct buffer_head *);
|
|
extern int journal_get_undo_access(handle_t *, struct buffer_head *);
|
|
extern int journal_dirty_data (handle_t *, struct buffer_head *);
|
|
extern int journal_dirty_metadata (handle_t *, struct buffer_head *);
|
|
extern void journal_release_buffer (handle_t *, struct buffer_head *);
|
|
extern int journal_forget (handle_t *, struct buffer_head *);
|
|
extern void journal_sync_buffer (struct buffer_head *);
|
|
extern int journal_invalidatepage(journal_t *,
|
|
struct page *, unsigned long);
|
|
extern int journal_try_to_free_buffers(journal_t *, struct page *, gfp_t);
|
|
extern int journal_stop(handle_t *);
|
|
extern int journal_flush (journal_t *);
|
|
extern void journal_lock_updates (journal_t *);
|
|
extern void journal_unlock_updates (journal_t *);
|
|
|
|
extern journal_t * journal_init_dev(struct block_device *bdev,
|
|
struct block_device *fs_dev,
|
|
int start, int len, int bsize);
|
|
extern journal_t * journal_init_inode (struct inode *);
|
|
extern int journal_update_format (journal_t *);
|
|
extern int journal_check_used_features
|
|
(journal_t *, unsigned long, unsigned long, unsigned long);
|
|
extern int journal_check_available_features
|
|
(journal_t *, unsigned long, unsigned long, unsigned long);
|
|
extern int journal_set_features
|
|
(journal_t *, unsigned long, unsigned long, unsigned long);
|
|
extern int journal_create (journal_t *);
|
|
extern int journal_load (journal_t *journal);
|
|
extern void journal_destroy (journal_t *);
|
|
extern int journal_recover (journal_t *journal);
|
|
extern int journal_wipe (journal_t *, int);
|
|
extern int journal_skip_recovery (journal_t *);
|
|
extern void journal_update_superblock (journal_t *, int);
|
|
extern void __journal_abort_hard (journal_t *);
|
|
extern void journal_abort (journal_t *, int);
|
|
extern int journal_errno (journal_t *);
|
|
extern void journal_ack_err (journal_t *);
|
|
extern int journal_clear_err (journal_t *);
|
|
extern int journal_bmap(journal_t *, unsigned long, unsigned long *);
|
|
extern int journal_force_commit(journal_t *);
|
|
|
|
/*
|
|
* journal_head management
|
|
*/
|
|
struct journal_head *journal_add_journal_head(struct buffer_head *bh);
|
|
struct journal_head *journal_grab_journal_head(struct buffer_head *bh);
|
|
void journal_remove_journal_head(struct buffer_head *bh);
|
|
void journal_put_journal_head(struct journal_head *jh);
|
|
|
|
/*
|
|
* handle management
|
|
*/
|
|
extern kmem_cache_t *jbd_handle_cache;
|
|
|
|
static inline handle_t *jbd_alloc_handle(gfp_t gfp_flags)
|
|
{
|
|
return kmem_cache_alloc(jbd_handle_cache, gfp_flags);
|
|
}
|
|
|
|
static inline void jbd_free_handle(handle_t *handle)
|
|
{
|
|
kmem_cache_free(jbd_handle_cache, handle);
|
|
}
|
|
|
|
/* Primary revoke support */
|
|
#define JOURNAL_REVOKE_DEFAULT_HASH 256
|
|
extern int journal_init_revoke(journal_t *, int);
|
|
extern void journal_destroy_revoke_caches(void);
|
|
extern int journal_init_revoke_caches(void);
|
|
|
|
extern void journal_destroy_revoke(journal_t *);
|
|
extern int journal_revoke (handle_t *,
|
|
unsigned long, struct buffer_head *);
|
|
extern int journal_cancel_revoke(handle_t *, struct journal_head *);
|
|
extern void journal_write_revoke_records(journal_t *, transaction_t *);
|
|
|
|
/* Recovery revoke support */
|
|
extern int journal_set_revoke(journal_t *, unsigned long, tid_t);
|
|
extern int journal_test_revoke(journal_t *, unsigned long, tid_t);
|
|
extern void journal_clear_revoke(journal_t *);
|
|
extern void journal_brelse_array(struct buffer_head *b[], int n);
|
|
extern void journal_switch_revoke_table(journal_t *journal);
|
|
|
|
/*
|
|
* The log thread user interface:
|
|
*
|
|
* Request space in the current transaction, and force transaction commit
|
|
* transitions on demand.
|
|
*/
|
|
|
|
int __log_space_left(journal_t *); /* Called with journal locked */
|
|
int log_start_commit(journal_t *journal, tid_t tid);
|
|
int __log_start_commit(journal_t *journal, tid_t tid);
|
|
int journal_start_commit(journal_t *journal, tid_t *tid);
|
|
int journal_force_commit_nested(journal_t *journal);
|
|
int log_wait_commit(journal_t *journal, tid_t tid);
|
|
int log_do_checkpoint(journal_t *journal);
|
|
|
|
void __log_wait_for_space(journal_t *journal);
|
|
extern void __journal_drop_transaction(journal_t *, transaction_t *);
|
|
extern int cleanup_journal_tail(journal_t *);
|
|
|
|
/* Debugging code only: */
|
|
|
|
#define jbd_ENOSYS() \
|
|
do { \
|
|
printk (KERN_ERR "JBD unimplemented function %s\n", __FUNCTION__); \
|
|
current->state = TASK_UNINTERRUPTIBLE; \
|
|
schedule(); \
|
|
} while (1)
|
|
|
|
/*
|
|
* is_journal_abort
|
|
*
|
|
* Simple test wrapper function to test the JFS_ABORT state flag. This
|
|
* bit, when set, indicates that we have had a fatal error somewhere,
|
|
* either inside the journaling layer or indicated to us by the client
|
|
* (eg. ext3), and that we and should not commit any further
|
|
* transactions.
|
|
*/
|
|
|
|
static inline int is_journal_aborted(journal_t *journal)
|
|
{
|
|
return journal->j_flags & JFS_ABORT;
|
|
}
|
|
|
|
static inline int is_handle_aborted(handle_t *handle)
|
|
{
|
|
if (handle->h_aborted)
|
|
return 1;
|
|
return is_journal_aborted(handle->h_transaction->t_journal);
|
|
}
|
|
|
|
static inline void journal_abort_handle(handle_t *handle)
|
|
{
|
|
handle->h_aborted = 1;
|
|
}
|
|
|
|
#endif /* __KERNEL__ */
|
|
|
|
/* Comparison functions for transaction IDs: perform comparisons using
|
|
* modulo arithmetic so that they work over sequence number wraps. */
|
|
|
|
static inline int tid_gt(tid_t x, tid_t y)
|
|
{
|
|
int difference = (x - y);
|
|
return (difference > 0);
|
|
}
|
|
|
|
static inline int tid_geq(tid_t x, tid_t y)
|
|
{
|
|
int difference = (x - y);
|
|
return (difference >= 0);
|
|
}
|
|
|
|
extern int journal_blocks_per_page(struct inode *inode);
|
|
|
|
/*
|
|
* Return the minimum number of blocks which must be free in the journal
|
|
* before a new transaction may be started. Must be called under j_state_lock.
|
|
*/
|
|
static inline int jbd_space_needed(journal_t *journal)
|
|
{
|
|
int nblocks = journal->j_max_transaction_buffers;
|
|
if (journal->j_committing_transaction)
|
|
nblocks += journal->j_committing_transaction->
|
|
t_outstanding_credits;
|
|
return nblocks;
|
|
}
|
|
|
|
/*
|
|
* Definitions which augment the buffer_head layer
|
|
*/
|
|
|
|
/* journaling buffer types */
|
|
#define BJ_None 0 /* Not journaled */
|
|
#define BJ_SyncData 1 /* Normal data: flush before commit */
|
|
#define BJ_Metadata 2 /* Normal journaled metadata */
|
|
#define BJ_Forget 3 /* Buffer superseded by this transaction */
|
|
#define BJ_IO 4 /* Buffer is for temporary IO use */
|
|
#define BJ_Shadow 5 /* Buffer contents being shadowed to the log */
|
|
#define BJ_LogCtl 6 /* Buffer contains log descriptors */
|
|
#define BJ_Reserved 7 /* Buffer is reserved for access by journal */
|
|
#define BJ_Locked 8 /* Locked for I/O during commit */
|
|
#define BJ_Types 9
|
|
|
|
extern int jbd_blocks_per_page(struct inode *inode);
|
|
|
|
#ifdef __KERNEL__
|
|
|
|
#define buffer_trace_init(bh) do {} while (0)
|
|
#define print_buffer_fields(bh) do {} while (0)
|
|
#define print_buffer_trace(bh) do {} while (0)
|
|
#define BUFFER_TRACE(bh, info) do {} while (0)
|
|
#define BUFFER_TRACE2(bh, bh2, info) do {} while (0)
|
|
#define JBUFFER_TRACE(jh, info) do {} while (0)
|
|
|
|
#endif /* __KERNEL__ */
|
|
|
|
#endif /* CONFIG_JBD || CONFIG_JBD_MODULE || !__KERNEL__ */
|
|
|
|
/*
|
|
* Compatibility no-ops which allow the kernel to compile without CONFIG_JBD
|
|
* go here.
|
|
*/
|
|
|
|
#if defined(__KERNEL__) && !(defined(CONFIG_JBD) || defined(CONFIG_JBD_MODULE))
|
|
|
|
#define J_ASSERT(expr) do {} while (0)
|
|
#define J_ASSERT_BH(bh, expr) do {} while (0)
|
|
#define buffer_jbd(bh) 0
|
|
#define journal_buffer_journal_lru(bh) 0
|
|
|
|
#endif /* defined(__KERNEL__) && !defined(CONFIG_JBD) */
|
|
#endif /* _LINUX_JBD_H */
|