mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-26 19:00:25 +00:00
![Artem Bityutskiy](/assets/img/avatar_default.png)
Currently JFFS2 file-system maps the VFS "superblock" abstraction to the write-buffer. Namely, it uses VFS services to synchronize the write-buffer periodically. The whole "superblock write-out" VFS infrastructure is served by the 'sync_supers()' kernel thread, which wakes up every 5 (by default) seconds and writes out all dirty superblock using the '->write_super()' call-back. But the problem with this thread is that it wastes power by waking up the system every 5 seconds no matter what. So we want to kill it completely and thus, we need to make file-systems to stop using the '->write_super' VFS service, and then remove it together with the kernel thread. This patch switches the JFFS2 write-buffer management from '->write_super()'/'->s_dirt' to a delayed work. Instead of setting the 's_dirt' flag we just schedule a delayed work for synchronizing the write-buffer. Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
164 lines
5.8 KiB
C
164 lines
5.8 KiB
C
/*
|
|
* JFFS2 -- Journalling Flash File System, Version 2.
|
|
*
|
|
* Copyright © 2001-2007 Red Hat, Inc.
|
|
* Copyright © 2004-2010 David Woodhouse <dwmw2@infradead.org>
|
|
*
|
|
* Created by David Woodhouse <dwmw2@infradead.org>
|
|
*
|
|
* For licensing information, see the file 'LICENCE' in this directory.
|
|
*
|
|
*/
|
|
|
|
#ifndef _JFFS2_FS_SB
|
|
#define _JFFS2_FS_SB
|
|
|
|
#include <linux/types.h>
|
|
#include <linux/spinlock.h>
|
|
#include <linux/workqueue.h>
|
|
#include <linux/completion.h>
|
|
#include <linux/mutex.h>
|
|
#include <linux/timer.h>
|
|
#include <linux/wait.h>
|
|
#include <linux/list.h>
|
|
#include <linux/rwsem.h>
|
|
|
|
#define JFFS2_SB_FLAG_RO 1
|
|
#define JFFS2_SB_FLAG_SCANNING 2 /* Flash scanning is in progress */
|
|
#define JFFS2_SB_FLAG_BUILDING 4 /* File system building is in progress */
|
|
|
|
struct jffs2_inodirty;
|
|
|
|
struct jffs2_mount_opts {
|
|
bool override_compr;
|
|
unsigned int compr;
|
|
|
|
/* The size of the reserved pool. The reserved pool is the JFFS2 flash
|
|
* space which may only be used by root cannot be used by the other
|
|
* users. This is implemented simply by means of not allowing the
|
|
* latter users to write to the file system if the amount if the
|
|
* available space is less then 'rp_size'. */
|
|
unsigned int rp_size;
|
|
};
|
|
|
|
/* A struct for the overall file system control. Pointers to
|
|
jffs2_sb_info structs are named `c' in the source code.
|
|
Nee jffs_control
|
|
*/
|
|
struct jffs2_sb_info {
|
|
struct mtd_info *mtd;
|
|
|
|
uint32_t highest_ino;
|
|
uint32_t checked_ino;
|
|
|
|
unsigned int flags;
|
|
|
|
struct task_struct *gc_task; /* GC task struct */
|
|
struct completion gc_thread_start; /* GC thread start completion */
|
|
struct completion gc_thread_exit; /* GC thread exit completion port */
|
|
|
|
struct mutex alloc_sem; /* Used to protect all the following
|
|
fields, and also to protect against
|
|
out-of-order writing of nodes. And GC. */
|
|
uint32_t cleanmarker_size; /* Size of an _inline_ CLEANMARKER
|
|
(i.e. zero for OOB CLEANMARKER */
|
|
|
|
uint32_t flash_size;
|
|
uint32_t used_size;
|
|
uint32_t dirty_size;
|
|
uint32_t wasted_size;
|
|
uint32_t free_size;
|
|
uint32_t erasing_size;
|
|
uint32_t bad_size;
|
|
uint32_t sector_size;
|
|
uint32_t unchecked_size;
|
|
|
|
uint32_t nr_free_blocks;
|
|
uint32_t nr_erasing_blocks;
|
|
|
|
/* Number of free blocks there must be before we... */
|
|
uint8_t resv_blocks_write; /* ... allow a normal filesystem write */
|
|
uint8_t resv_blocks_deletion; /* ... allow a normal filesystem deletion */
|
|
uint8_t resv_blocks_gctrigger; /* ... wake up the GC thread */
|
|
uint8_t resv_blocks_gcbad; /* ... pick a block from the bad_list to GC */
|
|
uint8_t resv_blocks_gcmerge; /* ... merge pages when garbage collecting */
|
|
/* Number of 'very dirty' blocks before we trigger immediate GC */
|
|
uint8_t vdirty_blocks_gctrigger;
|
|
|
|
uint32_t nospc_dirty_size;
|
|
|
|
uint32_t nr_blocks;
|
|
struct jffs2_eraseblock *blocks; /* The whole array of blocks. Used for getting blocks
|
|
* from the offset (blocks[ofs / sector_size]) */
|
|
struct jffs2_eraseblock *nextblock; /* The block we're currently filling */
|
|
|
|
struct jffs2_eraseblock *gcblock; /* The block we're currently garbage-collecting */
|
|
|
|
struct list_head clean_list; /* Blocks 100% full of clean data */
|
|
struct list_head very_dirty_list; /* Blocks with lots of dirty space */
|
|
struct list_head dirty_list; /* Blocks with some dirty space */
|
|
struct list_head erasable_list; /* Blocks which are completely dirty, and need erasing */
|
|
struct list_head erasable_pending_wbuf_list; /* Blocks which need erasing but only after the current wbuf is flushed */
|
|
struct list_head erasing_list; /* Blocks which are currently erasing */
|
|
struct list_head erase_checking_list; /* Blocks which are being checked and marked */
|
|
struct list_head erase_pending_list; /* Blocks which need erasing now */
|
|
struct list_head erase_complete_list; /* Blocks which are erased and need the clean marker written to them */
|
|
struct list_head free_list; /* Blocks which are free and ready to be used */
|
|
struct list_head bad_list; /* Bad blocks. */
|
|
struct list_head bad_used_list; /* Bad blocks with valid data in. */
|
|
|
|
spinlock_t erase_completion_lock; /* Protect free_list and erasing_list
|
|
against erase completion handler */
|
|
wait_queue_head_t erase_wait; /* For waiting for erases to complete */
|
|
|
|
wait_queue_head_t inocache_wq;
|
|
int inocache_hashsize;
|
|
struct jffs2_inode_cache **inocache_list;
|
|
spinlock_t inocache_lock;
|
|
|
|
/* Sem to allow jffs2_garbage_collect_deletion_dirent to
|
|
drop the erase_completion_lock while it's holding a pointer
|
|
to an obsoleted node. I don't like this. Alternatives welcomed. */
|
|
struct mutex erase_free_sem;
|
|
|
|
uint32_t wbuf_pagesize; /* 0 for NOR and other flashes with no wbuf */
|
|
|
|
#ifdef CONFIG_JFFS2_FS_WBUF_VERIFY
|
|
unsigned char *wbuf_verify; /* read-back buffer for verification */
|
|
#endif
|
|
#ifdef CONFIG_JFFS2_FS_WRITEBUFFER
|
|
unsigned char *wbuf; /* Write-behind buffer for NAND flash */
|
|
uint32_t wbuf_ofs;
|
|
uint32_t wbuf_len;
|
|
struct jffs2_inodirty *wbuf_inodes;
|
|
struct rw_semaphore wbuf_sem; /* Protects the write buffer */
|
|
|
|
struct delayed_work wbuf_dwork; /* write-buffer write-out work */
|
|
int wbuf_queued; /* non-zero delayed work is queued */
|
|
spinlock_t wbuf_dwork_lock; /* protects wbuf_dwork and and wbuf_queued */
|
|
|
|
unsigned char *oobbuf;
|
|
int oobavail; /* How many bytes are available for JFFS2 in OOB */
|
|
#endif
|
|
|
|
struct jffs2_summary *summary; /* Summary information */
|
|
struct jffs2_mount_opts mount_opts;
|
|
|
|
#ifdef CONFIG_JFFS2_FS_XATTR
|
|
#define XATTRINDEX_HASHSIZE (57)
|
|
uint32_t highest_xid;
|
|
uint32_t highest_xseqno;
|
|
struct list_head xattrindex[XATTRINDEX_HASHSIZE];
|
|
struct list_head xattr_unchecked;
|
|
struct list_head xattr_dead_list;
|
|
struct jffs2_xattr_ref *xref_dead_list;
|
|
struct jffs2_xattr_ref *xref_temp;
|
|
struct rw_semaphore xattr_sem;
|
|
uint32_t xdatum_mem_usage;
|
|
uint32_t xdatum_mem_threshold;
|
|
#endif
|
|
/* OS-private pointer for getting back to master superblock info */
|
|
void *os_priv;
|
|
};
|
|
|
|
#endif /* _JFFS2_FS_SB */
|