lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

[JFFS2] Core changes required to support JFFS2-on-Dataflash devices.

Browse Source 
DataFlash page-sizes are not a power of two (they're multiples of 528
bytes).  There are a few places in JFFS2 code where sector_size is used
as a bitmask.  A new macro (SECTOR_ADDR) was defined to calculate these
sector addresses. For non-DataFlash devices, the original (faster)
bitmask operation is still used.

In scan.c, the EMPTY_SCAN_SIZE was a constant of 1024.
Since this could be larger than the sector size of the DataFlash, this
is now basically set to MIN(sector_size, 1024).

Addition of a jffs2_is_writebuffered() macro.

Signed-off-by: Andrew Victor <andrew@sanpeople.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
Andrew Victor
2005-02-09 09:09:05 +00:00
committed by Thomas Gleixner
parent 045e9a5d51
commit 3be36675d4
5 changed files with 53 additions and 44 deletions
Download Patch File Download Diff File Expand all files Collapse all files

20
fs/jffs2/scan.c
View File

@ -7,7 +7,7 @@
*
* For licensing information, see the file 'LICENCE' in this directory.
*
* $Id: scan.c,v 1.115 2004/11/17 12:59:08 dedekind Exp $
* $Id: scan.c,v 1.116 2005/02/09 09:09:02 pavlov Exp $
*
*/
#include <linux/kernel.h>
@ -19,7 +19,7 @@
#include <linux/compiler.h>
#include "nodelist.h"
#define EMPTY_SCAN_SIZE 1024
#define DEFAULT_EMPTY_SCAN_SIZE 1024
#define DIRTY_SPACE(x) do { typeof(x) _x = (x); \
c->free_size -= _x; c->dirty_size += _x; \
@ -75,6 +75,14 @@ static inline int min_free(struct jffs2_sb_info *c)
return min;
}
static inline uint32_t EMPTY_SCAN_SIZE(uint32_t sector_size) {
if (sector_size < DEFAULT_EMPTY_SCAN_SIZE)
return sector_size;
else
return DEFAULT_EMPTY_SCAN_SIZE;
}
int jffs2_scan_medium(struct jffs2_sb_info *c)
{
int i, ret;
@ -316,7 +324,7 @@ static int jffs2_scan_eraseblock (struct jffs2_sb_info *c, struct jffs2_eraseblo
if (!buf_size) {
buf_len = c->sector_size;
} else {
buf_len = EMPTY_SCAN_SIZE;
buf_len = EMPTY_SCAN_SIZE(c->sector_size);
err = jffs2_fill_scan_buf(c, buf, buf_ofs, buf_len);
if (err)
return err;
@ -326,10 +334,10 @@ static int jffs2_scan_eraseblock (struct jffs2_sb_info *c, struct jffs2_eraseblo
ofs = 0;
/* Scan only 4KiB of 0xFF before declaring it's empty */
while(ofs < EMPTY_SCAN_SIZE && *(uint32_t *)(&buf[ofs]) == 0xFFFFFFFF)
while(ofs < EMPTY_SCAN_SIZE(c->sector_size) && *(uint32_t *)(&buf[ofs]) == 0xFFFFFFFF)
ofs += 4;
if (ofs == EMPTY_SCAN_SIZE) {
if (ofs == EMPTY_SCAN_SIZE(c->sector_size)) {
#ifdef CONFIG_JFFS2_FS_NAND
if (jffs2_cleanmarker_oob(c)) {
/* scan oob, take care of cleanmarker */
@ -423,7 +431,7 @@ scan_more:
bail now */
if (buf_ofs == jeb->offset && jeb->used_size == PAD(c->cleanmarker_size) &&
c->cleanmarker_size && !jeb->dirty_size && !jeb->first_node->next_in_ino) {
D1(printk(KERN_DEBUG "%d bytes at start of block seems clean... assuming all clean\n", EMPTY_SCAN_SIZE));
D1(printk(KERN_DEBUG "%d bytes at start of block seems clean... assuming all clean\n", EMPTY_SCAN_SIZE(c->sector_size)));
return BLK_STATE_CLEANMARKER;
}