1/*
2 * JFFS2 -- Journalling Flash File System, Version 2.
3 *
4 * Copyright © 2001-2007 Red Hat, Inc.
5 * Copyright © 2004-2010 David Woodhouse <dwmw2@infradead.org>
6 *
7 * Created by David Woodhouse <dwmw2@infradead.org>
8 *
9 * For licensing information, see the file 'LICENCE' in this directory.
10 *
11 */
12
13#ifndef _JFFS2_FS_SB
14#define _JFFS2_FS_SB
15
16#include <linux/types.h>
17#include <linux/spinlock.h>
18#include <linux/workqueue.h>
19#include <linux/completion.h>
20#include <linux/mutex.h>
21#include <linux/timer.h>
22#include <linux/wait.h>
23#include <linux/list.h>
24#include <linux/rwsem.h>
25
26#define JFFS2_SB_FLAG_RO 1
27#define JFFS2_SB_FLAG_SCANNING 2 /* Flash scanning is in progress */
28#define JFFS2_SB_FLAG_BUILDING 4 /* File system building is in progress */
29
30struct jffs2_inodirty;
31
32struct jffs2_mount_opts {
33 bool override_compr;
34 unsigned int compr;
35
36 /* The size of the reserved pool. The reserved pool is the JFFS2 flash
37 * space which may only be used by root cannot be used by the other
38 * users. This is implemented simply by means of not allowing the
39 * latter users to write to the file system if the amount if the
40 * available space is less then 'rp_size'. */
41 bool set_rp_size;
42 unsigned int rp_size;
43};
44
45/* A struct for the overall file system control. Pointers to
46 jffs2_sb_info structs are named `c' in the source code.
47 Nee jffs_control
48*/
49struct jffs2_sb_info {
50 struct mtd_info *mtd;
51
52 uint32_t highest_ino;
53 uint32_t check_ino; /* *NEXT* inode to be checked */
54
55 unsigned int flags;
56
57 struct task_struct *gc_task; /* GC task struct */
58 struct completion gc_thread_start; /* GC thread start completion */
59 struct completion gc_thread_exit; /* GC thread exit completion port */
60
61 struct mutex alloc_sem; /* Used to protect all the following
62 fields, and also to protect against
63 out-of-order writing of nodes. And GC. */
64 uint32_t cleanmarker_size; /* Size of an _inline_ CLEANMARKER
65 (i.e. zero for OOB CLEANMARKER */
66
67 uint32_t flash_size;
68 uint32_t used_size;
69 uint32_t dirty_size;
70 uint32_t wasted_size;
71 uint32_t free_size;
72 uint32_t erasing_size;
73 uint32_t bad_size;
74 uint32_t sector_size;
75 uint32_t unchecked_size;
76
77 uint32_t nr_free_blocks;
78 uint32_t nr_erasing_blocks;
79
80 /* Number of free blocks there must be before we... */
81 uint8_t resv_blocks_write; /* ... allow a normal filesystem write */
82 uint8_t resv_blocks_deletion; /* ... allow a normal filesystem deletion */
83 uint8_t resv_blocks_gctrigger; /* ... wake up the GC thread */
84 uint8_t resv_blocks_gcbad; /* ... pick a block from the bad_list to GC */
85 uint8_t resv_blocks_gcmerge; /* ... merge pages when garbage collecting */
86 /* Number of 'very dirty' blocks before we trigger immediate GC */
87 uint8_t vdirty_blocks_gctrigger;
88
89 uint32_t nospc_dirty_size;
90
91 uint32_t nr_blocks;
92 struct jffs2_eraseblock *blocks; /* The whole array of blocks. Used for getting blocks
93 * from the offset (blocks[ofs / sector_size]) */
94 struct jffs2_eraseblock *nextblock; /* The block we're currently filling */
95
96 struct jffs2_eraseblock *gcblock; /* The block we're currently garbage-collecting */
97
98 struct list_head clean_list; /* Blocks 100% full of clean data */
99 struct list_head very_dirty_list; /* Blocks with lots of dirty space */
100 struct list_head dirty_list; /* Blocks with some dirty space */
101 struct list_head erasable_list; /* Blocks which are completely dirty, and need erasing */
102 struct list_head erasable_pending_wbuf_list; /* Blocks which need erasing but only after the current wbuf is flushed */
103 struct list_head erasing_list; /* Blocks which are currently erasing */
104 struct list_head erase_checking_list; /* Blocks which are being checked and marked */
105 struct list_head erase_pending_list; /* Blocks which need erasing now */
106 struct list_head erase_complete_list; /* Blocks which are erased and need the clean marker written to them */
107 struct list_head free_list; /* Blocks which are free and ready to be used */
108 struct list_head bad_list; /* Bad blocks. */
109 struct list_head bad_used_list; /* Bad blocks with valid data in. */
110
111 spinlock_t erase_completion_lock; /* Protect free_list and erasing_list
112 against erase completion handler */
113 wait_queue_head_t erase_wait; /* For waiting for erases to complete */
114
115 wait_queue_head_t inocache_wq;
116 int inocache_hashsize;
117 struct jffs2_inode_cache **inocache_list;
118 spinlock_t inocache_lock;
119
120 /* Sem to allow jffs2_garbage_collect_deletion_dirent to
121 drop the erase_completion_lock while it's holding a pointer
122 to an obsoleted node. I don't like this. Alternatives welcomed. */
123 struct mutex erase_free_sem;
124
125 uint32_t wbuf_pagesize; /* 0 for NOR and other flashes with no wbuf */
126
127#ifdef CONFIG_JFFS2_FS_WBUF_VERIFY
128 unsigned char *wbuf_verify; /* read-back buffer for verification */
129#endif
130#ifdef CONFIG_JFFS2_FS_WRITEBUFFER
131 unsigned char *wbuf; /* Write-behind buffer for NAND flash */
132 uint32_t wbuf_ofs;
133 uint32_t wbuf_len;
134 struct jffs2_inodirty *wbuf_inodes;
135 struct rw_semaphore wbuf_sem; /* Protects the write buffer */
136
137 struct delayed_work wbuf_dwork; /* write-buffer write-out work */
138
139 unsigned char *oobbuf;
140 int oobavail; /* How many bytes are available for JFFS2 in OOB */
141#endif
142
143 struct jffs2_summary *summary; /* Summary information */
144 struct jffs2_mount_opts mount_opts;
145
146#ifdef CONFIG_JFFS2_FS_XATTR
147#define XATTRINDEX_HASHSIZE (57)
148 uint32_t highest_xid;
149 uint32_t highest_xseqno;
150 struct list_head xattrindex[XATTRINDEX_HASHSIZE];
151 struct list_head xattr_unchecked;
152 struct list_head xattr_dead_list;
153 struct jffs2_xattr_ref *xref_dead_list;
154 struct jffs2_xattr_ref *xref_temp;
155 struct rw_semaphore xattr_sem;
156 uint32_t xdatum_mem_usage;
157 uint32_t xdatum_mem_threshold;
158#endif
159 /* OS-private pointer for getting back to master superblock info */
160 void *os_priv;
161};
162
163#endif /* _JFFS2_FS_SB */
164

source code of linux/fs/jffs2/jffs2_fs_sb.h