linux/fs/logfs/logfs.h

736 lines
24 KiB
C
Raw Normal View History

/*
* fs/logfs/logfs.h
*
* As should be obvious for Linux kernel code, license is GPLv2
*
* Copyright (c) 2005-2008 Joern Engel <joern@logfs.org>
*
* Private header for logfs.
*/
#ifndef FS_LOGFS_LOGFS_H
#define FS_LOGFS_LOGFS_H
#undef __CHECK_ENDIAN__
#define __CHECK_ENDIAN__
#include <linux/btree.h>
#include <linux/crc32.h>
#include <linux/fs.h>
#include <linux/kernel.h>
#include <linux/mempool.h>
#include <linux/pagemap.h>
#include <linux/mtd/mtd.h>
#include "logfs_abi.h"
#define LOGFS_DEBUG_SUPER (0x0001)
#define LOGFS_DEBUG_SEGMENT (0x0002)
#define LOGFS_DEBUG_JOURNAL (0x0004)
#define LOGFS_DEBUG_DIR (0x0008)
#define LOGFS_DEBUG_FILE (0x0010)
#define LOGFS_DEBUG_INODE (0x0020)
#define LOGFS_DEBUG_READWRITE (0x0040)
#define LOGFS_DEBUG_GC (0x0080)
#define LOGFS_DEBUG_GC_NOISY (0x0100)
#define LOGFS_DEBUG_ALIASES (0x0200)
#define LOGFS_DEBUG_BLOCKMOVE (0x0400)
#define LOGFS_DEBUG_ALL (0xffffffff)
#define LOGFS_DEBUG (0x01)
/*
* To enable specific log messages, simply define LOGFS_DEBUG to match any
* or all of the above.
*/
#ifndef LOGFS_DEBUG
#define LOGFS_DEBUG (0)
#endif
#define log_cond(cond, fmt, arg...) do { \
if (cond) \
printk(KERN_DEBUG fmt, ##arg); \
} while (0)
#define log_super(fmt, arg...) \
log_cond(LOGFS_DEBUG & LOGFS_DEBUG_SUPER, fmt, ##arg)
#define log_segment(fmt, arg...) \
log_cond(LOGFS_DEBUG & LOGFS_DEBUG_SEGMENT, fmt, ##arg)
#define log_journal(fmt, arg...) \
log_cond(LOGFS_DEBUG & LOGFS_DEBUG_JOURNAL, fmt, ##arg)
#define log_dir(fmt, arg...) \
log_cond(LOGFS_DEBUG & LOGFS_DEBUG_DIR, fmt, ##arg)
#define log_file(fmt, arg...) \
log_cond(LOGFS_DEBUG & LOGFS_DEBUG_FILE, fmt, ##arg)
#define log_inode(fmt, arg...) \
log_cond(LOGFS_DEBUG & LOGFS_DEBUG_INODE, fmt, ##arg)
#define log_readwrite(fmt, arg...) \
log_cond(LOGFS_DEBUG & LOGFS_DEBUG_READWRITE, fmt, ##arg)
#define log_gc(fmt, arg...) \
log_cond(LOGFS_DEBUG & LOGFS_DEBUG_GC, fmt, ##arg)
#define log_gc_noisy(fmt, arg...) \
log_cond(LOGFS_DEBUG & LOGFS_DEBUG_GC_NOISY, fmt, ##arg)
#define log_aliases(fmt, arg...) \
log_cond(LOGFS_DEBUG & LOGFS_DEBUG_ALIASES, fmt, ##arg)
#define log_blockmove(fmt, arg...) \
log_cond(LOGFS_DEBUG & LOGFS_DEBUG_BLOCKMOVE, fmt, ##arg)
#define PG_pre_locked PG_owner_priv_1
#define PagePreLocked(page) test_bit(PG_pre_locked, &(page)->flags)
#define SetPagePreLocked(page) set_bit(PG_pre_locked, &(page)->flags)
#define ClearPagePreLocked(page) clear_bit(PG_pre_locked, &(page)->flags)
/* FIXME: This should really be somewhere in the 64bit area. */
#define LOGFS_LINK_MAX (1<<30)
/* Read-only filesystem */
#define LOGFS_SB_FLAG_RO 0x0001
#define LOGFS_SB_FLAG_DIRTY 0x0002
#define LOGFS_SB_FLAG_OBJ_ALIAS 0x0004
#define LOGFS_SB_FLAG_SHUTDOWN 0x0008
/* Write Control Flags */
#define WF_LOCK 0x01 /* take write lock */
#define WF_WRITE 0x02 /* write block */
#define WF_DELETE 0x04 /* delete old block */
typedef u8 __bitwise level_t;
typedef u8 __bitwise gc_level_t;
#define LEVEL(level) ((__force level_t)(level))
#define GC_LEVEL(gc_level) ((__force gc_level_t)(gc_level))
#define SUBLEVEL(level) ( (void)((level) == LEVEL(1)), \
(__force level_t)((__force u8)(level) - 1) )
/**
* struct logfs_area - area management information
*
* @a_sb: the superblock this area belongs to
* @a_is_open: 1 if the area is currently open, else 0
* @a_segno: segment number of area
* @a_written_bytes: number of bytes already written back
* @a_used_bytes: number of used bytes
* @a_ops: area operations (either journal or ostore)
* @a_erase_count: erase count
* @a_level: GC level
*/
struct logfs_area { /* a segment open for writing */
struct super_block *a_sb;
int a_is_open;
u32 a_segno;
u32 a_written_bytes;
u32 a_used_bytes;
const struct logfs_area_ops *a_ops;
u32 a_erase_count;
gc_level_t a_level;
};
/**
* struct logfs_area_ops - area operations
*
* @get_free_segment: fill area->ofs with the offset of a free segment
* @get_erase_count: fill area->erase_count (needs area->ofs)
* @erase_segment: erase and setup segment
*/
struct logfs_area_ops {
void (*get_free_segment)(struct logfs_area *area);
void (*get_erase_count)(struct logfs_area *area);
int (*erase_segment)(struct logfs_area *area);
};
struct logfs_super; /* forward */
/**
* struct logfs_device_ops - device access operations
*
* @readpage: read one page (mm page)
* @writeseg: write one segment. may be a partial segment
* @erase: erase one segment
* @read: read from the device
* @erase: erase part of the device
* @can_write_buf: decide whether wbuf can be written to ofs
*/
struct logfs_device_ops {
struct page *(*find_first_sb)(struct super_block *sb, u64 *ofs);
struct page *(*find_last_sb)(struct super_block *sb, u64 *ofs);
int (*write_sb)(struct super_block *sb, struct page *page);
int (*readpage)(void *_sb, struct page *page);
void (*writeseg)(struct super_block *sb, u64 ofs, size_t len);
int (*erase)(struct super_block *sb, loff_t ofs, size_t len,
int ensure_write);
int (*can_write_buf)(struct super_block *sb, u64 ofs);
void (*sync)(struct super_block *sb);
void (*put_device)(struct logfs_super *s);
};
/**
* struct candidate_list - list of similar candidates
*/
struct candidate_list {
struct rb_root rb_tree;
int count;
int maxcount;
int sort_by_ec;
};
/**
* struct gc_candidate - "candidate" segment to be garbage collected next
*
* @list: list (either free of low)
* @segno: segment number
* @valid: number of valid bytes
* @erase_count: erase count of segment
* @dist: distance from tree root
*
* Candidates can be on two lists. The free list contains electees rather
* than candidates - segments that no longer contain any valid data. The
* low list contains candidates to be picked for GC. It should be kept
* short. It is not required to always pick a perfect candidate. In the
* worst case GC will have to move more data than absolutely necessary.
*/
struct gc_candidate {
struct rb_node rb_node;
struct candidate_list *list;
u32 segno;
u32 valid;
u32 erase_count;
u8 dist;
};
/**
* struct logfs_journal_entry - temporary structure used during journal scan
*
* @used:
* @version: normalized version
* @len: length
* @offset: offset
*/
struct logfs_journal_entry {
int used;
s16 version;
u16 len;
u16 datalen;
u64 offset;
};
enum transaction_state {
CREATE_1 = 1,
CREATE_2,
UNLINK_1,
UNLINK_2,
CROSS_RENAME_1,
CROSS_RENAME_2,
TARGET_RENAME_1,
TARGET_RENAME_2,
TARGET_RENAME_3
};
/**
* struct logfs_transaction - essential fields to support atomic dirops
*
* @ino: target inode
* @dir: inode of directory containing dentry
* @pos: pos of dentry in directory
*/
struct logfs_transaction {
enum transaction_state state;
u64 ino;
u64 dir;
u64 pos;
};
/**
* struct logfs_shadow - old block in the shadow of a not-yet-committed new one
* @old_ofs: offset of old block on medium
* @new_ofs: offset of new block on medium
* @ino: inode number
* @bix: block index
* @old_len: size of old block, including header
* @new_len: size of new block, including header
* @level: block level
*/
struct logfs_shadow {
u64 old_ofs;
u64 new_ofs;
u64 ino;
u64 bix;
int old_len;
int new_len;
gc_level_t gc_level;
};
/**
* struct shadow_tree
* @new: shadows where old_ofs==0, indexed by new_ofs
* @old: shadows where old_ofs!=0, indexed by old_ofs
* @segment_map: bitfield of segments containing shadows
* @no_shadowed_segment: number of segments containing shadows
*/
struct shadow_tree {
struct btree_head64 new;
struct btree_head64 old;
struct btree_head32 segment_map;
int no_shadowed_segments;
};
struct object_alias_item {
struct list_head list;
__be64 val;
int child_no;
};
/**
* struct logfs_block - contains any block state
* @type: indirect block or inode
* @full: number of fully populated children
* @partial: number of partially populated children
*
* Most blocks are directly represented by page cache pages. But when a block
* becomes dirty, is part of a transaction, contains aliases or is otherwise
* special, a struct logfs_block is allocated to track the additional state.
* Inodes are very similar to indirect blocks, so they can also get one of
* these structures added when appropriate.
*/
#define BLOCK_INDIRECT 1 /* Indirect block */
#define BLOCK_INODE 2 /* Inode */
struct logfs_block_ops;
struct logfs_block {
struct list_head alias_list;
struct list_head item_list;
struct super_block *sb;
u64 ino;
u64 bix;
level_t level;
struct page *page;
struct inode *inode;
struct logfs_transaction *ta;
unsigned long alias_map[LOGFS_BLOCK_FACTOR / BITS_PER_LONG];
struct logfs_block_ops *ops;
int full;
int partial;
int reserved_bytes;
};
typedef int write_alias_t(struct super_block *sb, u64 ino, u64 bix,
level_t level, int child_no, __be64 val);
struct logfs_block_ops {
void (*write_block)(struct logfs_block *block);
void (*free_block)(struct super_block *sb, struct logfs_block*block);
int (*write_alias)(struct super_block *sb,
struct logfs_block *block,
write_alias_t *write_one_alias);
};
#define MAX_JOURNAL_ENTRIES 256
struct logfs_super {
struct mtd_info *s_mtd; /* underlying device */
struct block_device *s_bdev; /* underlying device */
const struct logfs_device_ops *s_devops;/* device access */
struct inode *s_master_inode; /* inode file */
struct inode *s_segfile_inode; /* segment file */
struct inode *s_mapping_inode; /* device mapping */
atomic_t s_pending_writes; /* outstanting bios */
long s_flags;
mempool_t *s_btree_pool; /* for btree nodes */
mempool_t *s_alias_pool; /* aliases in segment.c */
u64 s_feature_incompat;
u64 s_feature_ro_compat;
u64 s_feature_compat;
u64 s_feature_flags;
u64 s_sb_ofs[2];
struct page *s_erase_page; /* for dev_bdev.c */
/* alias.c fields */
struct btree_head32 s_segment_alias; /* remapped segments */
int s_no_object_aliases;
struct list_head s_object_alias; /* remapped objects */
struct btree_head128 s_object_alias_tree; /* remapped objects */
struct mutex s_object_alias_mutex;
/* dir.c fields */
struct mutex s_dirop_mutex; /* for creat/unlink/rename */
u64 s_victim_ino; /* used for atomic dir-ops */
u64 s_rename_dir; /* source directory ino */
u64 s_rename_pos; /* position of source dd */
/* gc.c fields */
long s_segsize; /* size of a segment */
int s_segshift; /* log2 of segment size */
long s_segmask; /* 1 << s_segshift - 1 */
long s_no_segs; /* segments on device */
long s_no_journal_segs; /* segments used for journal */
long s_no_blocks; /* blocks per segment */
long s_writesize; /* minimum write size */
int s_writeshift; /* log2 of write size */
u64 s_size; /* filesystem size */
struct logfs_area *s_area[LOGFS_NO_AREAS]; /* open segment array */
u64 s_gec; /* global erase count */
u64 s_wl_gec_ostore; /* time of last wl event */
u64 s_wl_gec_journal; /* time of last wl event */
u64 s_sweeper; /* current sweeper pos */
u8 s_ifile_levels; /* max level of ifile */
u8 s_iblock_levels; /* max level of regular files */
u8 s_data_levels; /* # of segments to leaf block*/
u8 s_total_levels; /* sum of above three */
struct btree_head32 s_cand_tree; /* all candidates */
struct candidate_list s_free_list; /* 100% free segments */
struct candidate_list s_reserve_list; /* Bad segment reserve */
struct candidate_list s_low_list[LOGFS_NO_AREAS];/* good candidates */
struct candidate_list s_ec_list; /* wear level candidates */
struct btree_head32 s_reserved_segments;/* sb, journal, bad, etc. */
/* inode.c fields */
u64 s_last_ino; /* highest ino used */
long s_inos_till_wrap;
u32 s_generation; /* i_generation for new files */
struct list_head s_freeing_list; /* inodes being freed */
/* journal.c fields */
struct mutex s_journal_mutex;
void *s_je; /* journal entry to compress */
void *s_compressed_je; /* block to write to journal */
u32 s_journal_seg[LOGFS_JOURNAL_SEGS]; /* journal segments */
u32 s_journal_ec[LOGFS_JOURNAL_SEGS]; /* journal erasecounts */
u64 s_last_version;
struct logfs_area *s_journal_area; /* open journal segment */
__be64 s_je_array[MAX_JOURNAL_ENTRIES];
int s_no_je;
int s_sum_index; /* for the 12 summaries */
struct shadow_tree s_shadow_tree;
int s_je_fill; /* index of current je */
/* readwrite.c fields */
struct mutex s_write_mutex;
int s_lock_count;
mempool_t *s_block_pool; /* struct logfs_block pool */
mempool_t *s_shadow_pool; /* struct logfs_shadow pool */
struct list_head s_writeback_list; /* writeback pages */
/*
* Space accounting:
* - s_used_bytes specifies space used to store valid data objects.
* - s_dirty_used_bytes is space used to store non-committed data
* objects. Those objects have already been written themselves,
* but they don't become valid until all indirect blocks up to the
* journal have been written as well.
* - s_dirty_free_bytes is space used to store the old copy of a
* replaced object, as long as the replacement is non-committed.
* In other words, it is the amount of space freed when all dirty
* blocks are written back.
* - s_free_bytes is the amount of free space available for any
* purpose.
* - s_root_reserve is the amount of free space available only to
* the root user. Non-privileged users can no longer write once
* this watermark has been reached.
* - s_speed_reserve is space which remains unused to speed up
* garbage collection performance.
* - s_dirty_pages is the space reserved for currently dirty pages.
* It is a pessimistic estimate, so some/most will get freed on
* page writeback.
*
* s_used_bytes + s_free_bytes + s_speed_reserve = total usable size
*/
u64 s_free_bytes;
u64 s_used_bytes;
u64 s_dirty_free_bytes;
u64 s_dirty_used_bytes;
u64 s_root_reserve;
u64 s_speed_reserve;
u64 s_dirty_pages;
/* Bad block handling:
* - s_bad_seg_reserve is a number of segments usually kept
* free. When encountering bad blocks, the affected segment's data
* is _temporarily_ moved to a reserved segment.
* - s_bad_segments is the number of known bad segments.
*/
u32 s_bad_seg_reserve;
u32 s_bad_segments;
};
/**
* struct logfs_inode - in-memory inode
*
* @vfs_inode: struct inode
* @li_data: data pointers
* @li_used_bytes: number of used bytes
* @li_freeing_list: used to track inodes currently being freed
* @li_flags: inode flags
* @li_refcount: number of internal (GC-induced) references
*/
struct logfs_inode {
struct inode vfs_inode;
u64 li_data[LOGFS_EMBEDDED_FIELDS];
u64 li_used_bytes;
struct list_head li_freeing_list;
struct logfs_block *li_block;
u32 li_flags;
u8 li_height;
int li_refcount;
};
#define journal_for_each(__i) for (__i = 0; __i < LOGFS_JOURNAL_SEGS; __i++)
#define for_each_area(__i) for (__i = 0; __i < LOGFS_NO_AREAS; __i++)
#define for_each_area_down(__i) for (__i = LOGFS_NO_AREAS - 1; __i >= 0; __i--)
/* compr.c */
int logfs_compress(void *in, void *out, size_t inlen, size_t outlen);
int logfs_uncompress(void *in, void *out, size_t inlen, size_t outlen);
int __init logfs_compr_init(void);
void logfs_compr_exit(void);
/* dev_bdev.c */
#ifdef CONFIG_BLOCK
int logfs_get_sb_bdev(struct logfs_super *s,
struct file_system_type *type,
const char *devname);
#else
static inline int logfs_get_sb_bdev(struct logfs_super *s,
struct file_system_type *type,
const char *devname)
{
return -ENODEV;
}
#endif
/* dev_mtd.c */
#ifdef CONFIG_MTD
int logfs_get_sb_mtd(struct logfs_super *s, int mtdnr);
#else
static inline int logfs_get_sb_mtd(struct logfs_super *s, int mtdnr)
{
return -ENODEV;
}
#endif
/* dir.c */
extern const struct inode_operations logfs_symlink_iops;
extern const struct inode_operations logfs_dir_iops;
extern const struct file_operations logfs_dir_fops;
int logfs_replay_journal(struct super_block *sb);
/* file.c */
extern const struct inode_operations logfs_reg_iops;
extern const struct file_operations logfs_reg_fops;
extern const struct address_space_operations logfs_reg_aops;
int logfs_readpage(struct file *file, struct page *page);
long logfs_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
int logfs_fsync(struct file *file, loff_t start, loff_t end, int datasync);
/* gc.c */
u32 get_best_cand(struct super_block *sb, struct candidate_list *list, u32 *ec);
void logfs_gc_pass(struct super_block *sb);
int logfs_check_areas(struct super_block *sb);
int logfs_init_gc(struct super_block *sb);
void logfs_cleanup_gc(struct super_block *sb);
/* inode.c */
extern const struct super_operations logfs_super_operations;
struct inode *logfs_iget(struct super_block *sb, ino_t ino);
struct inode *logfs_safe_iget(struct super_block *sb, ino_t ino, int *cookie);
void logfs_safe_iput(struct inode *inode, int cookie);
struct inode *logfs_new_inode(struct inode *dir, int mode);
struct inode *logfs_new_meta_inode(struct super_block *sb, u64 ino);
struct inode *logfs_read_meta_inode(struct super_block *sb, u64 ino);
int logfs_init_inode_cache(void);
void logfs_destroy_inode_cache(void);
void logfs_set_blocks(struct inode *inode, u64 no);
/* these logically belong into inode.c but actually reside in readwrite.c */
int logfs_read_inode(struct inode *inode);
logfs: Propagate page parameter to __logfs_write_inode During GC LogFS has to rewrite each valid block to a separate segment. Rewrite operation reads data from an old segment and writes it to a newly allocated segment. Since every write operation changes data block pointers maintained in inode, inode should also be rewritten. In GC path to avoid AB-BA deadlock LogFS marks a page with PG_pre_locked in addition to locking the page (PG_locked). The page lock is ignored iff the page is pre-locked. LogFS uses a special file called segment file. The segment file maintains an 8 bytes entry for every segment. It keeps track of erase count, level etc. for every segment. Bad things happen with a segment belonging to the segment file is GCed ------------[ cut here ]------------ kernel BUG at /home/prasad/logfs/readwrite.c:297! invalid opcode: 0000 [#1] SMP Modules linked in: logfs joydev usbhid hid psmouse e1000 i2c_piix4 serio_raw [last unloaded: logfs] Pid: 20161, comm: mount Not tainted 3.1.0-rc3+ #3 innotek GmbH VirtualBox EIP: 0060:[<f809132a>] EFLAGS: 00010292 CPU: 0 EIP is at logfs_lock_write_page+0x6a/0x70 [logfs] EAX: 00000027 EBX: f73f5b20 ECX: c16007c8 EDX: 00000094 ESI: 00000000 EDI: e59be6e4 EBP: c7337b28 ESP: c7337b18 DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 Process mount (pid: 20161, ti=c7336000 task=eb323f70 task.ti=c7336000) Stack: f8099a3d c7337b24 f73f5b20 00001002 c7337b50 f8091f6d f8099a4d f80994e4 00000003 00000000 c7337b68 00000000 c67e4400 00001000 c7337b80 f80935e5 00000000 00000000 00000000 00000000 e1fcf000 0000000f e59be618 c70bf900 Call Trace: [<f8091f6d>] logfs_get_write_page.clone.16+0xdd/0x100 [logfs] [<f80935e5>] logfs_mod_segment_entry+0x55/0x110 [logfs] [<f809460d>] logfs_get_segment_entry+0x1d/0x20 [logfs] [<f8091060>] ? logfs_cleanup_journal+0x50/0x50 [logfs] [<f809521b>] ostore_get_erase_count+0x1b/0x40 [logfs] [<f80965b8>] logfs_open_area+0xc8/0x150 [logfs] [<c141a7ec>] ? kmemleak_alloc+0x2c/0x60 [<f809668e>] __logfs_segment_write.clone.16+0x4e/0x1b0 [logfs] [<c10dd563>] ? mempool_kmalloc+0x13/0x20 [<c10dd563>] ? mempool_kmalloc+0x13/0x20 [<f809696f>] logfs_segment_write+0x17f/0x1d0 [logfs] [<f8092e8c>] logfs_write_i0+0x11c/0x180 [logfs] [<f8092f35>] logfs_write_direct+0x45/0x90 [logfs] [<f80934cd>] __logfs_write_buf+0xbd/0xf0 [logfs] [<c102900e>] ? kmap_atomic_prot+0x4e/0xe0 [<f809424b>] logfs_write_buf+0x3b/0x60 [logfs] [<f80947a9>] __logfs_write_inode+0xa9/0x110 [logfs] [<f8094cb0>] logfs_rewrite_block+0xc0/0x110 [logfs] [<f8095300>] ? get_mapping_page+0x10/0x60 [logfs] [<f8095aa0>] ? logfs_load_object_aliases+0x2e0/0x2f0 [logfs] [<f808e57d>] logfs_gc_segment+0x2ad/0x310 [logfs] [<f808e62a>] __logfs_gc_once+0x4a/0x80 [logfs] [<f808ed43>] logfs_gc_pass+0x683/0x6a0 [logfs] [<f8097a89>] logfs_mount+0x5a9/0x680 [logfs] [<c1126b21>] mount_fs+0x21/0xd0 [<c10f6f6f>] ? __alloc_percpu+0xf/0x20 [<c113da41>] ? alloc_vfsmnt+0xb1/0x130 [<c113db4b>] vfs_kern_mount+0x4b/0xa0 [<c113e06e>] do_kern_mount+0x3e/0xe0 [<c113f60d>] do_mount+0x34d/0x670 [<c10f2749>] ? strndup_user+0x49/0x70 [<c113fcab>] sys_mount+0x6b/0xa0 [<c142d87c>] syscall_call+0x7/0xb Code: f8 e8 8b 93 39 c9 8b 45 f8 3e 0f ba 28 00 19 d2 85 d2 74 ca eb d0 0f 0b 8d 45 fc 89 44 24 04 c7 04 24 3d 9a 09 f8 e8 09 92 39 c9 <0f> 0b 8d 74 26 00 55 89 e5 3e 8d 74 26 00 8b 10 80 e6 01 74 09 EIP: [<f809132a>] logfs_lock_write_page+0x6a/0x70 [logfs] SS:ESP 0068:c7337b18 ---[ end trace 96e67d5b3aa3d6ca ]--- The patch passes locked page to __logfs_write_inode. It calls function logfs_get_wblocks() to pre-lock the page. This ensures any further attempts to lock the page are ignored (esp from get_erase_count). Acked-by: Joern Engel <joern@logfs.org> Signed-off-by: Prasad Joshi <prasadjoshi.linux@gmail.com>
2011-10-02 18:16:51 +00:00
int __logfs_write_inode(struct inode *inode, struct page *, long flags);
void logfs_evict_inode(struct inode *inode);
/* journal.c */
void logfs_write_anchor(struct super_block *sb);
int logfs_init_journal(struct super_block *sb);
void logfs_cleanup_journal(struct super_block *sb);
int write_alias_journal(struct super_block *sb, u64 ino, u64 bix,
level_t level, int child_no, __be64 val);
void do_logfs_journal_wl_pass(struct super_block *sb);
/* readwrite.c */
pgoff_t logfs_pack_index(u64 bix, level_t level);
void logfs_unpack_index(pgoff_t index, u64 *bix, level_t *level);
int logfs_inode_write(struct inode *inode, const void *buf, size_t count,
loff_t bix, long flags, struct shadow_tree *shadow_tree);
int logfs_readpage_nolock(struct page *page);
int logfs_write_buf(struct inode *inode, struct page *page, long flags);
int logfs_delete(struct inode *inode, pgoff_t index,
struct shadow_tree *shadow_tree);
int logfs_rewrite_block(struct inode *inode, u64 bix, u64 ofs,
gc_level_t gc_level, long flags);
int logfs_is_valid_block(struct super_block *sb, u64 ofs, u64 ino, u64 bix,
gc_level_t gc_level);
int logfs_truncate(struct inode *inode, u64 size);
u64 logfs_seek_hole(struct inode *inode, u64 bix);
u64 logfs_seek_data(struct inode *inode, u64 bix);
int logfs_open_segfile(struct super_block *sb);
int logfs_init_rw(struct super_block *sb);
void logfs_cleanup_rw(struct super_block *sb);
void logfs_add_transaction(struct inode *inode, struct logfs_transaction *ta);
void logfs_del_transaction(struct inode *inode, struct logfs_transaction *ta);
void logfs_write_block(struct logfs_block *block, long flags);
int logfs_write_obj_aliases_pagecache(struct super_block *sb);
void logfs_get_segment_entry(struct super_block *sb, u32 segno,
struct logfs_segment_entry *se);
void logfs_set_segment_used(struct super_block *sb, u64 ofs, int increment);
void logfs_set_segment_erased(struct super_block *sb, u32 segno, u32 ec,
gc_level_t gc_level);
void logfs_set_segment_reserved(struct super_block *sb, u32 segno);
void logfs_set_segment_unreserved(struct super_block *sb, u32 segno, u32 ec);
struct logfs_block *__alloc_block(struct super_block *sb,
u64 ino, u64 bix, level_t level);
void __free_block(struct super_block *sb, struct logfs_block *block);
void btree_write_block(struct logfs_block *block);
void initialize_block_counters(struct page *page, struct logfs_block *block,
__be64 *array, int page_is_empty);
int logfs_exist_block(struct inode *inode, u64 bix);
int get_page_reserve(struct inode *inode, struct page *page);
logfs: take write mutex lock during fsync and sync LogFS uses super->s_write_mutex while writing data to disk. Taking the same mutex lock in sync and fsync code path solves the following BUG: ------------[ cut here ]------------ kernel BUG at /home/prasad/logfs/dev_bdev.c:134! Pid: 2387, comm: flush-253:16 Not tainted 3.0.0+ #4 Bochs Bochs RIP: 0010:[<ffffffffa007deed>] [<ffffffffa007deed>] bdev_writeseg+0x25d/0x270 [logfs] Call Trace: [<ffffffffa007c381>] logfs_open_area+0x91/0x150 [logfs] [<ffffffff8128dcb2>] ? find_level.clone.9+0x62/0x100 [<ffffffffa007c49c>] __logfs_segment_write.clone.20+0x5c/0x190 [logfs] [<ffffffff810ef005>] ? mempool_kmalloc+0x15/0x20 [<ffffffff810ef383>] ? mempool_alloc+0x53/0x130 [<ffffffffa007c7a4>] logfs_segment_write+0x1d4/0x230 [logfs] [<ffffffffa0078f8e>] logfs_write_i0+0x12e/0x190 [logfs] [<ffffffffa0079300>] __logfs_write_rec+0x140/0x220 [logfs] [<ffffffffa0079444>] logfs_write_rec+0x64/0xd0 [logfs] [<ffffffffa00795b6>] __logfs_write_buf+0x106/0x110 [logfs] [<ffffffffa007a13e>] logfs_write_buf+0x4e/0x80 [logfs] [<ffffffffa0073e33>] __logfs_writepage+0x23/0x80 [logfs] [<ffffffffa007410c>] logfs_writepage+0xdc/0x110 [logfs] [<ffffffff810f5ba7>] __writepage+0x17/0x40 [<ffffffff810f6208>] write_cache_pages+0x208/0x4f0 [<ffffffff810f5b90>] ? set_page_dirty+0x70/0x70 [<ffffffff810f653a>] generic_writepages+0x4a/0x70 [<ffffffff810f75d1>] do_writepages+0x21/0x40 [<ffffffff8116b9d1>] writeback_single_inode+0x101/0x250 [<ffffffff8116bdbd>] writeback_sb_inodes+0xed/0x1c0 [<ffffffff8116c5fb>] writeback_inodes_wb+0x7b/0x1e0 [<ffffffff8116cc23>] wb_writeback+0x4c3/0x530 [<ffffffff814d984d>] ? sub_preempt_count+0x9d/0xd0 [<ffffffff8116cd6b>] wb_do_writeback+0xdb/0x290 [<ffffffff814d984d>] ? sub_preempt_count+0x9d/0xd0 [<ffffffff814d6208>] ? _raw_spin_unlock_irqrestore+0x18/0x40 [<ffffffff8105aa5a>] ? del_timer+0x8a/0x120 [<ffffffff8116cfac>] bdi_writeback_thread+0x8c/0x2e0 [<ffffffff8116cf20>] ? wb_do_writeback+0x290/0x290 [<ffffffff8106d2e6>] kthread+0x96/0xa0 [<ffffffff814de514>] kernel_thread_helper+0x4/0x10 [<ffffffff8106d250>] ? kthread_worker_fn+0x190/0x190 [<ffffffff814de510>] ? gs_change+0xb/0xb RIP [<ffffffffa007deed>] bdev_writeseg+0x25d/0x270 [logfs] ---[ end trace 0211ad60a57657c4 ]--- Reviewed-by: Joern Engel <joern@logfs.org> Signed-off-by: Prasad Joshi <prasadjoshi.linux@gmail.com>
2012-01-28 06:06:06 +00:00
void logfs_get_wblocks(struct super_block *sb, struct page *page, int lock);
void logfs_put_wblocks(struct super_block *sb, struct page *page, int lock);
extern struct logfs_block_ops indirect_block_ops;
/* segment.c */
int logfs_erase_segment(struct super_block *sb, u32 ofs, int ensure_erase);
int wbuf_read(struct super_block *sb, u64 ofs, size_t len, void *buf);
int logfs_segment_read(struct inode *inode, struct page *page, u64 ofs, u64 bix,
level_t level);
int logfs_segment_write(struct inode *inode, struct page *page,
struct logfs_shadow *shadow);
int logfs_segment_delete(struct inode *inode, struct logfs_shadow *shadow);
int logfs_load_object_aliases(struct super_block *sb,
struct logfs_obj_alias *oa, int count);
void move_page_to_btree(struct page *page);
int logfs_init_mapping(struct super_block *sb);
void logfs_sync_area(struct logfs_area *area);
void logfs_sync_segments(struct super_block *sb);
void freeseg(struct super_block *sb, u32 segno);
/* area handling */
int logfs_init_areas(struct super_block *sb);
void logfs_cleanup_areas(struct super_block *sb);
int logfs_open_area(struct logfs_area *area, size_t bytes);
int __logfs_buf_write(struct logfs_area *area, u64 ofs, void *buf, size_t len,
int use_filler);
static inline int logfs_buf_write(struct logfs_area *area, u64 ofs,
void *buf, size_t len)
{
return __logfs_buf_write(area, ofs, buf, len, 0);
}
static inline int logfs_buf_recover(struct logfs_area *area, u64 ofs,
void *buf, size_t len)
{
return __logfs_buf_write(area, ofs, buf, len, 1);
}
/* super.c */
struct page *emergency_read_begin(struct address_space *mapping, pgoff_t index);
void emergency_read_end(struct page *page);
void logfs_crash_dump(struct super_block *sb);
int logfs_statfs(struct dentry *dentry, struct kstatfs *stats);
int logfs_check_ds(struct logfs_disk_super *ds);
int logfs_write_sb(struct super_block *sb);
static inline struct logfs_super *logfs_super(struct super_block *sb)
{
return sb->s_fs_info;
}
static inline struct logfs_inode *logfs_inode(struct inode *inode)
{
return container_of(inode, struct logfs_inode, vfs_inode);
}
static inline void logfs_set_ro(struct super_block *sb)
{
logfs_super(sb)->s_flags |= LOGFS_SB_FLAG_RO;
}
#define LOGFS_BUG(sb) do { \
struct super_block *__sb = sb; \
logfs_crash_dump(__sb); \
logfs_super(__sb)->s_flags |= LOGFS_SB_FLAG_RO; \
BUG(); \
} while (0)
#define LOGFS_BUG_ON(condition, sb) \
do { if (unlikely(condition)) LOGFS_BUG((sb)); } while (0)
static inline __be32 logfs_crc32(void *data, size_t len, size_t skip)
{
return cpu_to_be32(crc32(~0, data+skip, len-skip));
}
static inline u8 logfs_type(struct inode *inode)
{
return (inode->i_mode >> 12) & 15;
}
static inline pgoff_t logfs_index(struct super_block *sb, u64 pos)
{
return pos >> sb->s_blocksize_bits;
}
static inline u64 dev_ofs(struct super_block *sb, u32 segno, u32 ofs)
{
return ((u64)segno << logfs_super(sb)->s_segshift) + ofs;
}
static inline u32 seg_no(struct super_block *sb, u64 ofs)
{
return ofs >> logfs_super(sb)->s_segshift;
}
static inline u32 seg_ofs(struct super_block *sb, u64 ofs)
{
return ofs & logfs_super(sb)->s_segmask;
}
static inline u64 seg_align(struct super_block *sb, u64 ofs)
{
return ofs & ~logfs_super(sb)->s_segmask;
}
static inline struct logfs_block *logfs_block(struct page *page)
{
return (void *)page->private;
}
static inline level_t shrink_level(gc_level_t __level)
{
u8 level = (__force u8)__level;
if (level >= LOGFS_MAX_LEVELS)
level -= LOGFS_MAX_LEVELS;
return (__force level_t)level;
}
static inline gc_level_t expand_level(u64 ino, level_t __level)
{
u8 level = (__force u8)__level;
if (ino == LOGFS_INO_MASTER) {
/* ifile has separate areas */
level += LOGFS_MAX_LEVELS;
}
return (__force gc_level_t)level;
}
static inline int logfs_block_shift(struct super_block *sb, level_t level)
{
level = shrink_level((__force gc_level_t)level);
return (__force int)level * (sb->s_blocksize_bits - 3);
}
static inline u64 logfs_block_mask(struct super_block *sb, level_t level)
{
return ~0ull << logfs_block_shift(sb, level);
}
static inline struct logfs_area *get_area(struct super_block *sb,
gc_level_t gc_level)
{
return logfs_super(sb)->s_area[(__force u8)gc_level];
}
static inline void logfs_mempool_destroy(mempool_t *pool)
{
if (pool)
mempool_destroy(pool);
}
#endif