xref: /linux/fs/jffs2/jffs2_fs_sb.h (revision 8fa5723aa7e053d498336b48448b292fc2e0458b)
1 /*
2  * JFFS2 -- Journalling Flash File System, Version 2.
3  *
4  * Copyright © 2001-2007 Red Hat, Inc.
5  *
6  * Created by David Woodhouse <dwmw2@infradead.org>
7  *
8  * For licensing information, see the file 'LICENCE' in this directory.
9  *
10  */
11 
12 #ifndef _JFFS2_FS_SB
13 #define _JFFS2_FS_SB
14 
15 #include <linux/types.h>
16 #include <linux/spinlock.h>
17 #include <linux/workqueue.h>
18 #include <linux/completion.h>
19 #include <linux/mutex.h>
20 #include <linux/timer.h>
21 #include <linux/wait.h>
22 #include <linux/list.h>
23 #include <linux/rwsem.h>
24 
25 #define JFFS2_SB_FLAG_RO 1
26 #define JFFS2_SB_FLAG_SCANNING 2 /* Flash scanning is in progress */
27 #define JFFS2_SB_FLAG_BUILDING 4 /* File system building is in progress */
28 
29 struct jffs2_inodirty;
30 
31 /* A struct for the overall file system control.  Pointers to
32    jffs2_sb_info structs are named `c' in the source code.
33    Nee jffs_control
34 */
35 struct jffs2_sb_info {
36 	struct mtd_info *mtd;
37 
38 	uint32_t highest_ino;
39 	uint32_t checked_ino;
40 
41 	unsigned int flags;
42 
43 	struct task_struct *gc_task;	/* GC task struct */
44 	struct completion gc_thread_start; /* GC thread start completion */
45 	struct completion gc_thread_exit; /* GC thread exit completion port */
46 
47 	struct mutex alloc_sem;		/* Used to protect all the following
48 					   fields, and also to protect against
49 					   out-of-order writing of nodes. And GC. */
50 	uint32_t cleanmarker_size;	/* Size of an _inline_ CLEANMARKER
51 					 (i.e. zero for OOB CLEANMARKER */
52 
53 	uint32_t flash_size;
54 	uint32_t used_size;
55 	uint32_t dirty_size;
56 	uint32_t wasted_size;
57 	uint32_t free_size;
58 	uint32_t erasing_size;
59 	uint32_t bad_size;
60 	uint32_t sector_size;
61 	uint32_t unchecked_size;
62 
63 	uint32_t nr_free_blocks;
64 	uint32_t nr_erasing_blocks;
65 
66 	/* Number of free blocks there must be before we... */
67 	uint8_t resv_blocks_write;	/* ... allow a normal filesystem write */
68 	uint8_t resv_blocks_deletion;	/* ... allow a normal filesystem deletion */
69 	uint8_t resv_blocks_gctrigger;	/* ... wake up the GC thread */
70 	uint8_t resv_blocks_gcbad;	/* ... pick a block from the bad_list to GC */
71 	uint8_t resv_blocks_gcmerge;	/* ... merge pages when garbage collecting */
72 	/* Number of 'very dirty' blocks before we trigger immediate GC */
73 	uint8_t vdirty_blocks_gctrigger;
74 
75 	uint32_t nospc_dirty_size;
76 
77 	uint32_t nr_blocks;
78 	struct jffs2_eraseblock *blocks;	/* The whole array of blocks. Used for getting blocks
79 						 * from the offset (blocks[ofs / sector_size]) */
80 	struct jffs2_eraseblock *nextblock;	/* The block we're currently filling */
81 
82 	struct jffs2_eraseblock *gcblock;	/* The block we're currently garbage-collecting */
83 
84 	struct list_head clean_list;		/* Blocks 100% full of clean data */
85 	struct list_head very_dirty_list;	/* Blocks with lots of dirty space */
86 	struct list_head dirty_list;		/* Blocks with some dirty space */
87 	struct list_head erasable_list;		/* Blocks which are completely dirty, and need erasing */
88 	struct list_head erasable_pending_wbuf_list;	/* Blocks which need erasing but only after the current wbuf is flushed */
89 	struct list_head erasing_list;		/* Blocks which are currently erasing */
90 	struct list_head erase_checking_list;	/* Blocks which are being checked and marked */
91 	struct list_head erase_pending_list;	/* Blocks which need erasing now */
92 	struct list_head erase_complete_list;	/* Blocks which are erased and need the clean marker written to them */
93 	struct list_head free_list;		/* Blocks which are free and ready to be used */
94 	struct list_head bad_list;		/* Bad blocks. */
95 	struct list_head bad_used_list;		/* Bad blocks with valid data in. */
96 
97 	spinlock_t erase_completion_lock;	/* Protect free_list and erasing_list
98 						   against erase completion handler */
99 	wait_queue_head_t erase_wait;		/* For waiting for erases to complete */
100 
101 	wait_queue_head_t inocache_wq;
102 	struct jffs2_inode_cache **inocache_list;
103 	spinlock_t inocache_lock;
104 
105 	/* Sem to allow jffs2_garbage_collect_deletion_dirent to
106 	   drop the erase_completion_lock while it's holding a pointer
107 	   to an obsoleted node. I don't like this. Alternatives welcomed. */
108 	struct mutex erase_free_sem;
109 
110 	uint32_t wbuf_pagesize; /* 0 for NOR and other flashes with no wbuf */
111 
112 #ifdef CONFIG_JFFS2_FS_WBUF_VERIFY
113 	unsigned char *wbuf_verify; /* read-back buffer for verification */
114 #endif
115 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER
116 	unsigned char *wbuf; /* Write-behind buffer for NAND flash */
117 	uint32_t wbuf_ofs;
118 	uint32_t wbuf_len;
119 	struct jffs2_inodirty *wbuf_inodes;
120 	struct rw_semaphore wbuf_sem;	/* Protects the write buffer */
121 
122 	unsigned char *oobbuf;
123 	int oobavail; /* How many bytes are available for JFFS2 in OOB */
124 #endif
125 
126 	struct jffs2_summary *summary;		/* Summary information */
127 
128 #ifdef CONFIG_JFFS2_FS_XATTR
129 #define XATTRINDEX_HASHSIZE	(57)
130 	uint32_t highest_xid;
131 	uint32_t highest_xseqno;
132 	struct list_head xattrindex[XATTRINDEX_HASHSIZE];
133 	struct list_head xattr_unchecked;
134 	struct list_head xattr_dead_list;
135 	struct jffs2_xattr_ref *xref_dead_list;
136 	struct jffs2_xattr_ref *xref_temp;
137 	struct rw_semaphore xattr_sem;
138 	uint32_t xdatum_mem_usage;
139 	uint32_t xdatum_mem_threshold;
140 #endif
141 	/* OS-private pointer for getting back to master superblock info */
142 	void *os_priv;
143 };
144 
145 #endif /* _JFFS2_FB_SB */
146