JFFS2-on-DataFlash : 1 - Core changes
Andrew Victor
andrew at sanpeople.com
Tue Feb 1 03:44:15 EST 2005
hi,
Based on the previous comments, the patch has been split up.
The changes included in this patch are:
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.
Regards,
Andrew Victor
diff -urN -x CVS mtd.orig/fs/jffs2/erase.c mtd.core/fs/jffs2/erase.c
--- mtd.orig/fs/jffs2/erase.c Wed Jan 26 16:07:57 2005
+++ mtd.core/fs/jffs2/erase.c Tue Feb 1 10:06:13 2005
@@ -233,7 +233,7 @@
continue;
}
- if (((*prev)->flash_offset & ~(c->sector_size -1)) == jeb->offset) {
+ if (SECTOR_ADDR((*prev)->flash_offset) == jeb->offset) {
/* It's in the block we're erasing */
struct jffs2_raw_node_ref *this;
diff -urN -x CVS mtd.orig/fs/jffs2/gc.c mtd.core/fs/jffs2/gc.c
--- mtd.orig/fs/jffs2/gc.c Wed Jan 26 16:07:57 2005
+++ mtd.core/fs/jffs2/gc.c Tue Feb 1 10:06:13 2005
@@ -816,8 +816,7 @@
/* Doesn't matter if there's one in the same erase block. We're going to
delete it too at the same time. */
- if ((raw->flash_offset & ~(c->sector_size-1)) ==
- (fd->raw->flash_offset & ~(c->sector_size-1)))
+ if (SECTOR_ADDR(raw->flash_offset) == SECTOR_ADDR(fd->raw->flash_offset))
continue;
D1(printk(KERN_DEBUG "Check potential deletion dirent at %08x\n", ref_offset(raw)));
diff -urN -x CVS mtd.orig/fs/jffs2/os-linux.h mtd.core/fs/jffs2/os-linux.h
--- mtd.orig/fs/jffs2/os-linux.h Wed Jan 26 16:07:58 2005
+++ mtd.core/fs/jffs2/os-linux.h Tue Feb 1 10:06:13 2005
@@ -97,7 +97,10 @@
#endif
}
+#define SECTOR_ADDR(x) ( ((unsigned long)(x) & ~(c->sector_size-1)) )
+
#define jffs2_is_readonly(c) (OFNI_BS_2SFFJ(c)->s_flags & MS_RDONLY)
+#define jffs2_is_writebuffered(c) (c->wbuf != NULL)
#if (!defined CONFIG_JFFS2_FS_NAND && !defined CONFIG_JFFS2_FS_NOR_ECC)
#define jffs2_can_mark_obsolete(c) (1)
diff -urN -x CVS mtd.orig/fs/jffs2/scan.c mtd.core/fs/jffs2/scan.c
--- mtd.orig/fs/jffs2/scan.c Wed Jan 26 16:07:58 2005
+++ mtd.core/fs/jffs2/scan.c Tue Feb 1 10:07:55 2005
@@ -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 @@
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 @@
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 @@
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 @@
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;
}
diff -urN -x CVS mtd.orig/fs/jffs2/wbuf.c mtd.core/fs/jffs2/wbuf.c
--- mtd.orig/fs/jffs2/wbuf.c Wed Jan 26 16:07:58 2005
+++ mtd.core/fs/jffs2/wbuf.c Tue Feb 1 10:06:13 2005
@@ -415,9 +415,9 @@
int ret;
size_t retlen;
- /* Nothing to do if not NAND flash. In particular, we shouldn't
+ /* Nothing to do if not write-buffering the flash. In particular, we shouldn't
del_timer() the timer we never initialised. */
- if (jffs2_can_mark_obsolete(c))
+ if (!jffs2_is_writebuffered(c))
return 0;
if (!down_trylock(&c->alloc_sem)) {
@@ -426,7 +426,7 @@
BUG();
}
- if(!c->wbuf || !c->wbuf_len)
+ if (!c->wbuf_len) /* already checked c->wbuf above */
return 0;
/* claim remaining space on the page
@@ -614,7 +614,7 @@
uint32_t outvec_to = to;
/* If not NAND flash, don't bother */
- if (!c->wbuf)
+ if (!jffs2_is_writebuffered(c))
return jffs2_flash_direct_writev(c, invecs, count, to, retlen);
down_write(&c->wbuf_sem);
@@ -643,7 +643,7 @@
erase block. Anything else, and you die.
New block starts at xxx000c (0-b = block header)
*/
- if ( (to & ~(c->sector_size-1)) != (c->wbuf_ofs & ~(c->sector_size-1)) ) {
+ if (SECTOR_ADDR(to) != SECTOR_ADDR(c->wbuf_ofs)) {
/* It's a write to a new block */
if (c->wbuf_len) {
D1(printk(KERN_DEBUG "jffs2_flash_writev() to 0x%lx causes flush of wbuf at 0x%08x\n", (unsigned long)to, c->wbuf_ofs));
@@ -841,7 +841,7 @@
{
struct kvec vecs[1];
- if (jffs2_can_mark_obsolete(c))
+ if (!jffs2_is_writebuffered(c))
return c->mtd->write(c->mtd, ofs, len, retlen, buf);
vecs[0].iov_base = (unsigned char *) buf;
@@ -857,39 +857,39 @@
loff_t orbf = 0, owbf = 0, lwbf = 0;
int ret;
+ if (!jffs2_is_writebuffered(c))
+ return c->mtd->read(c->mtd, ofs, len, retlen, buf);
+
/* Read flash */
- if (!jffs2_can_mark_obsolete(c)) {
- down_read(&c->wbuf_sem);
+ down_read(&c->wbuf_sem);
- if (jffs2_cleanmarker_oob(c))
- ret = c->mtd->read_ecc(c->mtd, ofs, len, retlen, buf, NULL, c->oobinfo);
- else
- ret = c->mtd->read(c->mtd, ofs, len, retlen, buf);
+ if (jffs2_cleanmarker_oob(c))
+ ret = c->mtd->read_ecc(c->mtd, ofs, len, retlen, buf, NULL, c->oobinfo);
+ else
+ ret = c->mtd->read(c->mtd, ofs, len, retlen, buf);
- if ( (ret == -EBADMSG) && (*retlen == len) ) {
- printk(KERN_WARNING "mtd->read(0x%zx bytes from 0x%llx) returned ECC error\n",
- len, ofs);
- /*
- * We have the raw data without ECC correction in the buffer, maybe
- * we are lucky and all data or parts are correct. We check the node.
- * If data are corrupted node check will sort it out.
- * We keep this block, it will fail on write or erase and the we
- * mark it bad. Or should we do that now? But we should give him a chance.
- * Maybe we had a system crash or power loss before the ecc write or
- * a erase was completed.
- * So we return success. :)
- */
- ret = 0;
- }
- } else
- return c->mtd->read(c->mtd, ofs, len, retlen, buf);
+ if ( (ret == -EBADMSG) && (*retlen == len) ) {
+ printk(KERN_WARNING "mtd->read(0x%zx bytes from 0x%llx) returned ECC error\n",
+ len, ofs);
+ /*
+ * We have the raw data without ECC correction in the buffer, maybe
+ * we are lucky and all data or parts are correct. We check the node.
+ * If data are corrupted node check will sort it out.
+ * We keep this block, it will fail on write or erase and the we
+ * mark it bad. Or should we do that now? But we should give him a chance.
+ * Maybe we had a system crash or power loss before the ecc write or
+ * a erase was completed.
+ * So we return success. :)
+ */
+ ret = 0;
+ }
/* if no writebuffer available or write buffer empty, return */
if (!c->wbuf_pagesize || !c->wbuf_len)
goto exit;
/* if we read in a different block, return */
- if ( (ofs & ~(c->sector_size-1)) != (c->wbuf_ofs & ~(c->sector_size-1)) )
+ if (SECTOR_ADDR(ofs) != SECTOR_ADDR(c->wbuf_ofs))
goto exit;
if (ofs >= c->wbuf_ofs) {
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