Merge branch 'writeback-workqueue' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq into for-3.10/core

Tejun writes:

-----

This is the pull request for the earlier patchset[1] with the same
name.  It's only three patches (the first one was committed to
workqueue tree) but the merge strategy is a bit involved due to the
dependencies.

* Because the conversion needs features from wq/for-3.10,
  block/for-3.10/core is based on rc3, and wq/for-3.10 has conflicts
  with rc3, I pulled mainline (rc5) into wq/for-3.10 to prevent those
  workqueue conflicts from flaring up in block tree.

* Resolving the issue that Jan and Dave raised about debugging
  requires arch-wide changes.  The patchset is being worked on[2] but
  it'll have to go through -mm after these changes show up in -next,
  and not included in this pull request.

The three commits are located in the following git branch.

  git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq.git writeback-workqueue

Pulling it into block/for-3.10/core produces a conflict in
drivers/md/raid5.c between the following two commits.

  e3620a3ad5 ("MD RAID5: Avoid accessing gendisk or queue structs when not available")
  2f6db2a707 ("raid5: use bio_reset()")

The conflict is trivial - one removes an "if ()" conditional while the
other removes "rbi->bi_next = NULL" right above it.  We just need to
remove both.  The merged branch is available at

  git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq.git block-test-merge

so that you can use it for verification.  The test merge commit has
proper merge description.

While these changes are a bit of pain to route, they make code simpler
and even have, while minute, measureable performance gain[3] even on a
workload which isn't particularly favorable to showing the benefits of
this conversion.

----

Fixed up the conflict.

Conflicts:
	drivers/md/raid5.c

Signed-off-by: Jens Axboe <axboe@kernel.dk>

3 files changed, 90 insertions, 58 deletions

diff --git a/drivers/mtd/bcm47xxpart.c b/drivers/mtd/bcm47xxpart.c
index 63feb75cc8e0..9279a9174f84 100644
--- a/drivers/mtd/bcm47xxpart.c
+++ b/drivers/mtd/bcm47xxpart.c
@@ -19,6 +19,12 @@
 /* 10 parts were found on sflash on Netgear WNDR4500 */
 #define BCM47XXPART_MAX_PARTS		12
 
+/*
+ * Amount of bytes we read when analyzing each block of flash memory.
+ * Set it big enough to allow detecting partition and reading important data.
+ */
+#define BCM47XXPART_BYTES_TO_READ	0x404
+
 /* Magics */
 #define BOARD_DATA_MAGIC		0x5246504D	/* MPFR */
 #define POT_MAGIC1			0x54544f50	/* POTT */
@@ -57,17 +63,15 @@ static int bcm47xxpart_parse(struct mtd_info *master,
 	struct trx_header *trx;
 	int trx_part = -1;
 	int last_trx_part = -1;
-	int max_bytes_to_read = 0x8004;
+	int possible_nvram_sizes[] = { 0x8000, 0xF000, 0x10000, };
 
 	if (blocksize <= 0x10000)
 		blocksize = 0x10000;
-	if (blocksize == 0x20000)
-		max_bytes_to_read = 0x18004;
 
 	/* Alloc */
 	parts = kzalloc(sizeof(struct mtd_partition) * BCM47XXPART_MAX_PARTS,
 			GFP_KERNEL);
-	buf = kzalloc(max_bytes_to_read, GFP_KERNEL);
+	buf = kzalloc(BCM47XXPART_BYTES_TO_READ, GFP_KERNEL);
 
 	/* Parse block by block looking for magics */
 	for (offset = 0; offset <= master->size - blocksize;
@@ -82,7 +86,7 @@ static int bcm47xxpart_parse(struct mtd_info *master,
 		}
 
 		/* Read beginning of the block */
-		if (mtd_read(master, offset, max_bytes_to_read,
+		if (mtd_read(master, offset, BCM47XXPART_BYTES_TO_READ,
 			     &bytes_read, (uint8_t *)buf) < 0) {
 			pr_err("mtd_read error while parsing (offset: 0x%X)!\n",
 			       offset);
@@ -96,20 +100,6 @@ static int bcm47xxpart_parse(struct mtd_info *master,
 			continue;
 		}
 
-		/* Standard NVRAM */
-		if (buf[0x000 / 4] == NVRAM_HEADER ||
-		    buf[0x1000 / 4] == NVRAM_HEADER ||
-		    buf[0x8000 / 4] == NVRAM_HEADER ||
-		    (blocksize == 0x20000 && (
-		      buf[0x10000 / 4] == NVRAM_HEADER ||
-		      buf[0x11000 / 4] == NVRAM_HEADER ||
-		      buf[0x18000 / 4] == NVRAM_HEADER))) {
-			bcm47xxpart_add_part(&parts[curr_part++], "nvram",
-					     offset, 0);
-			offset = rounddown(offset, blocksize);
-			continue;
-		}
-
 		/*
 		 * board_data starts with board_id which differs across boards,
 		 * but we can use 'MPFR' (hopefully) magic at 0x100
@@ -178,6 +168,30 @@ static int bcm47xxpart_parse(struct mtd_info *master,
 			continue;
 		}
 	}
+
+	/* Look for NVRAM at the end of the last block. */
+	for (i = 0; i < ARRAY_SIZE(possible_nvram_sizes); i++) {
+		if (curr_part > BCM47XXPART_MAX_PARTS) {
+			pr_warn("Reached maximum number of partitions, scanning stopped!\n");
+			break;
+		}
+
+		offset = master->size - possible_nvram_sizes[i];
+		if (mtd_read(master, offset, 0x4, &bytes_read,
+			     (uint8_t *)buf) < 0) {
+			pr_err("mtd_read error while reading at offset 0x%X!\n",
+			       offset);
+			continue;
+		}
+
+		/* Standard NVRAM */
+		if (buf[0] == NVRAM_HEADER) {
+			bcm47xxpart_add_part(&parts[curr_part++], "nvram",
+					     master->size - blocksize, 0);
+			break;
+		}
+	}
+
 	kfree(buf);
 
 	/*
diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index 43214151b882..42c63927609d 100644
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -1523,6 +1523,14 @@ static int nand_do_read_ops(struct mtd_info *mtd, loff_t from,
 					oobreadlen -= toread;
 				}
 			}
+
+			if (chip->options & NAND_NEED_READRDY) {
+				/* Apply delay or wait for ready/busy pin */
+				if (!chip->dev_ready)
+					udelay(chip->chip_delay);
+				else
+					nand_wait_ready(mtd);
+			}
 		} else {
 			memcpy(buf, chip->buffers->databuf + col, bytes);
 			buf += bytes;
@@ -1787,6 +1795,14 @@ static int nand_do_read_oob(struct mtd_info *mtd, loff_t from,
 		len = min(len, readlen);
 		buf = nand_transfer_oob(chip, buf, ops, len);
 
+		if (chip->options & NAND_NEED_READRDY) {
+			/* Apply delay or wait for ready/busy pin */
+			if (!chip->dev_ready)
+				udelay(chip->chip_delay);
+			else
+				nand_wait_ready(mtd);
+		}
+
 		readlen -= len;
 		if (!readlen)
 			break;
diff --git a/drivers/mtd/nand/nand_ids.c b/drivers/mtd/nand/nand_ids.c
index e3aa2748a6e7..9c612388e5de 100644
--- a/drivers/mtd/nand/nand_ids.c
+++ b/drivers/mtd/nand/nand_ids.c
@@ -22,49 +22,51 @@
 *	512	512 Byte page size
 */
 struct nand_flash_dev nand_flash_ids[] = {
+#define SP_OPTIONS NAND_NEED_READRDY
+#define SP_OPTIONS16 (SP_OPTIONS | NAND_BUSWIDTH_16)
 
 #ifdef CONFIG_MTD_NAND_MUSEUM_IDS
-	{"NAND 1MiB 5V 8-bit",		0x6e, 256, 1, 0x1000, 0},
-	{"NAND 2MiB 5V 8-bit",		0x64, 256, 2, 0x1000, 0},
-	{"NAND 4MiB 5V 8-bit",		0x6b, 512, 4, 0x2000, 0},
-	{"NAND 1MiB 3,3V 8-bit",	0xe8, 256, 1, 0x1000, 0},
-	{"NAND 1MiB 3,3V 8-bit",	0xec, 256, 1, 0x1000, 0},
-	{"NAND 2MiB 3,3V 8-bit",	0xea, 256, 2, 0x1000, 0},
-	{"NAND 4MiB 3,3V 8-bit",	0xd5, 512, 4, 0x2000, 0},
-	{"NAND 4MiB 3,3V 8-bit",	0xe3, 512, 4, 0x2000, 0},
-	{"NAND 4MiB 3,3V 8-bit",	0xe5, 512, 4, 0x2000, 0},
-	{"NAND 8MiB 3,3V 8-bit",	0xd6, 512, 8, 0x2000, 0},
-
-	{"NAND 8MiB 1,8V 8-bit",	0x39, 512, 8, 0x2000, 0},
-	{"NAND 8MiB 3,3V 8-bit",	0xe6, 512, 8, 0x2000, 0},
-	{"NAND 8MiB 1,8V 16-bit",	0x49, 512, 8, 0x2000, NAND_BUSWIDTH_16},
-	{"NAND 8MiB 3,3V 16-bit",	0x59, 512, 8, 0x2000, NAND_BUSWIDTH_16},
+	{"NAND 1MiB 5V 8-bit",		0x6e, 256, 1, 0x1000, SP_OPTIONS},
+	{"NAND 2MiB 5V 8-bit",		0x64, 256, 2, 0x1000, SP_OPTIONS},
+	{"NAND 4MiB 5V 8-bit",		0x6b, 512, 4, 0x2000, SP_OPTIONS},
+	{"NAND 1MiB 3,3V 8-bit",	0xe8, 256, 1, 0x1000, SP_OPTIONS},
+	{"NAND 1MiB 3,3V 8-bit",	0xec, 256, 1, 0x1000, SP_OPTIONS},
+	{"NAND 2MiB 3,3V 8-bit",	0xea, 256, 2, 0x1000, SP_OPTIONS},
+	{"NAND 4MiB 3,3V 8-bit",	0xd5, 512, 4, 0x2000, SP_OPTIONS},
+	{"NAND 4MiB 3,3V 8-bit",	0xe3, 512, 4, 0x2000, SP_OPTIONS},
+	{"NAND 4MiB 3,3V 8-bit",	0xe5, 512, 4, 0x2000, SP_OPTIONS},
+	{"NAND 8MiB 3,3V 8-bit",	0xd6, 512, 8, 0x2000, SP_OPTIONS},
+
+	{"NAND 8MiB 1,8V 8-bit",	0x39, 512, 8, 0x2000, SP_OPTIONS},
+	{"NAND 8MiB 3,3V 8-bit",	0xe6, 512, 8, 0x2000, SP_OPTIONS},
+	{"NAND 8MiB 1,8V 16-bit",	0x49, 512, 8, 0x2000, SP_OPTIONS16},
+	{"NAND 8MiB 3,3V 16-bit",	0x59, 512, 8, 0x2000, SP_OPTIONS16},
 #endif
 
-	{"NAND 16MiB 1,8V 8-bit",	0x33, 512, 16, 0x4000, 0},
-	{"NAND 16MiB 3,3V 8-bit",	0x73, 512, 16, 0x4000, 0},
-	{"NAND 16MiB 1,8V 16-bit",	0x43, 512, 16, 0x4000, NAND_BUSWIDTH_16},
-	{"NAND 16MiB 3,3V 16-bit",	0x53, 512, 16, 0x4000, NAND_BUSWIDTH_16},
-
-	{"NAND 32MiB 1,8V 8-bit",	0x35, 512, 32, 0x4000, 0},
-	{"NAND 32MiB 3,3V 8-bit",	0x75, 512, 32, 0x4000, 0},
-	{"NAND 32MiB 1,8V 16-bit",	0x45, 512, 32, 0x4000, NAND_BUSWIDTH_16},
-	{"NAND 32MiB 3,3V 16-bit",	0x55, 512, 32, 0x4000, NAND_BUSWIDTH_16},
-
-	{"NAND 64MiB 1,8V 8-bit",	0x36, 512, 64, 0x4000, 0},
-	{"NAND 64MiB 3,3V 8-bit",	0x76, 512, 64, 0x4000, 0},
-	{"NAND 64MiB 1,8V 16-bit",	0x46, 512, 64, 0x4000, NAND_BUSWIDTH_16},
-	{"NAND 64MiB 3,3V 16-bit",	0x56, 512, 64, 0x4000, NAND_BUSWIDTH_16},
-
-	{"NAND 128MiB 1,8V 8-bit",	0x78, 512, 128, 0x4000, 0},
-	{"NAND 128MiB 1,8V 8-bit",	0x39, 512, 128, 0x4000, 0},
-	{"NAND 128MiB 3,3V 8-bit",	0x79, 512, 128, 0x4000, 0},
-	{"NAND 128MiB 1,8V 16-bit",	0x72, 512, 128, 0x4000, NAND_BUSWIDTH_16},
-	{"NAND 128MiB 1,8V 16-bit",	0x49, 512, 128, 0x4000, NAND_BUSWIDTH_16},
-	{"NAND 128MiB 3,3V 16-bit",	0x74, 512, 128, 0x4000, NAND_BUSWIDTH_16},
-	{"NAND 128MiB 3,3V 16-bit",	0x59, 512, 128, 0x4000, NAND_BUSWIDTH_16},
-
-	{"NAND 256MiB 3,3V 8-bit",	0x71, 512, 256, 0x4000, 0},
+	{"NAND 16MiB 1,8V 8-bit",	0x33, 512, 16, 0x4000, SP_OPTIONS},
+	{"NAND 16MiB 3,3V 8-bit",	0x73, 512, 16, 0x4000, SP_OPTIONS},
+	{"NAND 16MiB 1,8V 16-bit",	0x43, 512, 16, 0x4000, SP_OPTIONS16},
+	{"NAND 16MiB 3,3V 16-bit",	0x53, 512, 16, 0x4000, SP_OPTIONS16},
+
+	{"NAND 32MiB 1,8V 8-bit",	0x35, 512, 32, 0x4000, SP_OPTIONS},
+	{"NAND 32MiB 3,3V 8-bit",	0x75, 512, 32, 0x4000, SP_OPTIONS},
+	{"NAND 32MiB 1,8V 16-bit",	0x45, 512, 32, 0x4000, SP_OPTIONS16},
+	{"NAND 32MiB 3,3V 16-bit",	0x55, 512, 32, 0x4000, SP_OPTIONS16},
+
+	{"NAND 64MiB 1,8V 8-bit",	0x36, 512, 64, 0x4000, SP_OPTIONS},
+	{"NAND 64MiB 3,3V 8-bit",	0x76, 512, 64, 0x4000, SP_OPTIONS},
+	{"NAND 64MiB 1,8V 16-bit",	0x46, 512, 64, 0x4000, SP_OPTIONS16},
+	{"NAND 64MiB 3,3V 16-bit",	0x56, 512, 64, 0x4000, SP_OPTIONS16},
+
+	{"NAND 128MiB 1,8V 8-bit",	0x78, 512, 128, 0x4000, SP_OPTIONS},
+	{"NAND 128MiB 1,8V 8-bit",	0x39, 512, 128, 0x4000, SP_OPTIONS},
+	{"NAND 128MiB 3,3V 8-bit",	0x79, 512, 128, 0x4000, SP_OPTIONS},
+	{"NAND 128MiB 1,8V 16-bit",	0x72, 512, 128, 0x4000, SP_OPTIONS16},
+	{"NAND 128MiB 1,8V 16-bit",	0x49, 512, 128, 0x4000, SP_OPTIONS16},
+	{"NAND 128MiB 3,3V 16-bit",	0x74, 512, 128, 0x4000, SP_OPTIONS16},
+	{"NAND 128MiB 3,3V 16-bit",	0x59, 512, 128, 0x4000, SP_OPTIONS16},
+
+	{"NAND 256MiB 3,3V 8-bit",	0x71, 512, 256, 0x4000, SP_OPTIONS},
 
 	/*
 	 * These are the new chips with large page size. The pagesize and the