Commit c2aecda7 authored by Joakim Tjernlund's avatar Joakim Tjernlund Committed by David Woodhouse
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[JFFS2] Speed up mount for directly-mapped NOR flash 



Remove excessive scanning of empty flash after a clean
marker for users of the point/unpoint method. cfi_cmdset_0001
uses point/unpoint by default iff flash mapping is linear.
The speedup is several orders of magnitude if FS is less than
half full.

Signed-off-by: default avatarJoakim Tjernlund <Joakim.Tjernlund@transmode.se>
Signed-off-by: default avatarDavid Woodhouse <dwmw2@infradead.org>
parent 10731f83

fs/jffs2/scan.c

+11 −4
Original line number Diff line number Diff line
@@ -636,16 +636,17 @@ scan_more: 


		if (*(uint32_t *)(&buf[ofs-buf_ofs]) == 0xffffffff) {

			uint32_t inbuf_ofs;

			uint32_t empty_start;

			uint32_t empty_start, scan_end;



			empty_start = ofs;

			ofs += 4;

			scan_end = min_t(uint32_t, EMPTY_SCAN_SIZE(c->sector_size)/8, buf_len);



			D1(printk(KERN_DEBUG "Found empty flash at 0x%08x\n", ofs));

		more_empty:

			inbuf_ofs = ofs - buf_ofs;

			while (inbuf_ofs < buf_len) {

				if (*(uint32_t *)(&buf[inbuf_ofs]) != 0xffffffff) {

			while (inbuf_ofs < scan_end) {

				if (unlikely(*(uint32_t *)(&buf[inbuf_ofs]) != 0xffffffff)) {

					printk(KERN_WARNING "Empty flash at 0x%08x ends at 0x%08x\n",

					       empty_start, ofs);

					if ((err = jffs2_scan_dirty_space(c, jeb, ofs-empty_start)))
@@ -666,6 +667,10 @@ scan_more: 
				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;

			}

			if (!buf_size && (scan_end != buf_len)) {/* XIP/point case */

				scan_end = buf_len;

				goto more_empty;

			}

			

			/* See how much more there is to read in this eraseblock... */

			buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
@@ -676,6 +681,8 @@ scan_more: 
					  empty_start));

				break;

			}

			/* point never reaches here */

			scan_end = buf_len;

			D1(printk(KERN_DEBUG "Reading another 0x%x at 0x%08x\n", buf_len, ofs));

			err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);

			if (err)

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