[v2,2/4] Add bio/request flags for using ZBC/ZAC commands

diff --git a/MAINTAINERS b/MAINTAINERS
index ed42cb6..d9fafa2 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -12662,6 +12662,15 @@  F:	Documentation/networking/z8530drv.txt
 F:	drivers/net/hamradio/*scc.c
 F:	drivers/net/hamradio/z8530.h
 
+ZBC AND ZBC BLOCK DEVICES
+M:	Shaun Tancheff <shaun.tancheff@seagate.com>
+W:	http://seagate.com
+W:	https://github.com/Seagate/ZDM-Device-Mapper
+L:	linux-block@vger.kernel.org
+S:	Maintained
+F:	include/linux/blkzoned_api.h
+F:	include/uapi/linux/blkzoned_api.h
+
 ZBUD COMPRESSED PAGE ALLOCATOR
 M:	Seth Jennings <sjenning@redhat.com>
 L:	linux-mm@kvack.org
diff --git a/block/blk-lib.c b/block/blk-lib.c
index 23d7f30..ce4168a 100644
--- a/block/blk-lib.c
+++ b/block/blk-lib.c
@@ -6,6 +6,7 @@ 
 #include <linux/bio.h>
 #include <linux/blkdev.h>
 #include <linux/scatterlist.h>
+#include <linux/blkzoned_api.h>
 
 #include "blk.h"
 
@@ -249,3 +250,99 @@  int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
 	return __blkdev_issue_zeroout(bdev, sector, nr_sects, gfp_mask);
 }
 EXPORT_SYMBOL(blkdev_issue_zeroout);
+
+/**
+ * blkdev_issue_zone_report - queue a report zones operation
+ * @bdev:	target blockdev
+ * @op_flags:	extra bio rw flags. If unsure, use 0.
+ * @sector:	starting sector (report will include this sector).
+ * @opt:	See: zone_report_option, default is 0 (all zones).
+ * @page:	one or more contiguous pages.
+ * @pgsz:	up to size of page in bytes, size of report.
+ * @gfp_mask:	memory allocation flags (for bio_alloc)
+ *
+ * Description:
+ *    Issue a zone report request for the sectors in question.
+ */
+int blkdev_issue_zone_report(struct block_device *bdev, unsigned int op_flags,
+			     sector_t sector, u8 opt, struct page *page,
+			     size_t pgsz, gfp_t gfp_mask)
+{
+	struct bdev_zone_report *conv = page_address(page);
+	struct bio *bio;
+	unsigned int nr_iovecs = 1;
+	int ret = 0;
+
+	if (pgsz < (sizeof(struct bdev_zone_report) +
+		    sizeof(struct bdev_zone_descriptor)))
+		return -EINVAL;
+
+	bio = bio_alloc(gfp_mask, nr_iovecs);
+	if (!bio)
+		return -ENOMEM;
+
+	conv->descriptor_count = 0;
+	bio->bi_iter.bi_sector = sector;
+	bio->bi_bdev = bdev;
+	bio->bi_vcnt = 0;
+	bio->bi_iter.bi_size = 0;
+
+	op_flags |= REQ_REPORT_ZONES;
+
+	/* FUTURE ... when streamid is available: */
+	/* bio_set_streamid(bio, opt); */
+
+	bio_add_page(bio, page, pgsz, 0);
+	ret = submit_bio_wait(READ | op_flags, bio);
+
+	/*
+	 * When our request it nak'd the underlying device maybe conventional
+	 * so ... report a single conventional zone the size of the device.
+	 */
+	if (ret == -EIO && conv->descriptor_count) {
+		/* Adjust the conventional to the size of the partition ... */
+		__be64 blksz = cpu_to_be64(bdev->bd_part->nr_sects);
+
+		conv->maximum_lba = blksz;
+		conv->descriptors[0].type = ZTYP_CONVENTIONAL;
+		conv->descriptors[0].flags = ZCOND_CONVENTIONAL << 4;
+		conv->descriptors[0].length = blksz;
+		conv->descriptors[0].lba_start = 0;
+		conv->descriptors[0].lba_wptr = blksz;
+		ret = 0;
+	}
+	bio_put(bio);
+	return ret;
+}
+EXPORT_SYMBOL(blkdev_issue_zone_report);
+
+/**
+ * blkdev_issue_zone_action - queue a report zones operation
+ * @bdev:	target blockdev
+ * @op_flags:	REQ_OPEN_ZONE, REQ_CLOSE_ZONE, or REQ_RESET_ZONE.
+ * @sector:	starting lba of sector
+ * @gfp_mask:	memory allocation flags (for bio_alloc)
+ *
+ * Description:
+ *    Issue a zone report request for the sectors in question.
+ */
+int blkdev_issue_zone_action(struct block_device *bdev, unsigned int op_flags,
+			     sector_t sector, gfp_t gfp_mask)
+{
+	int ret;
+	struct bio *bio;
+
+	bio = bio_alloc(gfp_mask, 1);
+	if (!bio)
+		return -ENOMEM;
+
+	bio->bi_iter.bi_sector = sector;
+	bio->bi_bdev = bdev;
+	bio->bi_vcnt = 0;
+	bio->bi_iter.bi_size = 0;
+
+	ret = submit_bio_wait(WRITE | op_flags, bio);
+	bio_put(bio);
+	return ret;
+}
+EXPORT_SYMBOL(blkdev_issue_zone_action);
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index f459dff..06b54d5 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -52,6 +52,7 @@ 
 #include <linux/slab.h>
 #include <linux/pm_runtime.h>
 #include <linux/pr.h>
+#include <linux/blkzoned_api.h>
 #include <asm/uaccess.h>
 #include <asm/unaligned.h>
 
@@ -1133,11 +1134,105 @@  static int sd_setup_read_write_cmnd(struct scsi_cmnd *SCpnt)
 	return ret;
 }
 
+static int sd_setup_zoned_cmnd(struct scsi_cmnd *cmd)
+{
+	struct request *rq = cmd->request;
+	struct scsi_device *sdp = cmd->device;
+	struct scsi_disk *sdkp = scsi_disk(rq->rq_disk);
+	struct bio *bio = rq->bio;
+	sector_t sector = blk_rq_pos(rq);
+	struct gendisk *disk = rq->rq_disk;
+	unsigned int nr_bytes = blk_rq_bytes(rq);
+	int ret = BLKPREP_KILL;
+	u8 allbit = 0;
+
+	if (rq->cmd_flags & REQ_REPORT_ZONES && rq_data_dir(rq) == READ) {
+		WARN_ON(nr_bytes == 0);
+
+		/*
+		 * For conventional drives generate a report that shows a
+		 * large single convetional zone the size of the block device
+		 */
+		if (sdkp->zoned != 1 && sdkp->device->type != TYPE_ZBC) {
+			void *src;
+			struct bdev_zone_report *conv;
+
+			if (nr_bytes < sizeof(struct bdev_zone_report))
+				goto out;
+
+			src = kmap_atomic(bio->bi_io_vec->bv_page);
+			conv = src + bio->bi_io_vec->bv_offset;
+			conv->descriptor_count = cpu_to_be32(1);
+			conv->same_field = ZS_ALL_SAME;
+			conv->maximum_lba = cpu_to_be64(disk->part0.nr_sects);
+			kunmap_atomic(src);
+			goto out;
+		}
+
+		ret = scsi_init_io(cmd);
+		if (ret != BLKPREP_OK)
+			goto out;
+
+		cmd = rq->special;
+		if (sdp->changed) {
+			pr_err("SCSI disk has been changed or is not present.");
+			ret = BLKPREP_KILL;
+			goto out;
+		}
+
+		cmd->cmd_len = 16;
+		memset(cmd->cmnd, 0, cmd->cmd_len);
+		cmd->cmnd[0] = ZBC_IN;
+		cmd->cmnd[1] = ZI_REPORT_ZONES;
+		put_unaligned_be64(sector, &cmd->cmnd[2]);
+		put_unaligned_be32(nr_bytes, &cmd->cmnd[10]);
+		/* FUTURE ... when streamid is available */
+		/* cmd->cmnd[14] = bio_get_streamid(bio); */
+		cmd->sc_data_direction = DMA_FROM_DEVICE;
+		cmd->sdb.length = nr_bytes;
+		cmd->transfersize = sdp->sector_size;
+		cmd->underflow = 0;
+		cmd->allowed = SD_MAX_RETRIES;
+		ret = BLKPREP_OK;
+		goto out;
+	}
+
+	if (sdkp->zoned != 1 && sdkp->device->type != TYPE_ZBC)
+		goto out;
+
+	if (sector == ~0ul) {
+		allbit = 1;
+		sector = 0;
+	}
+
+	cmd->cmd_len = 16;
+	memset(cmd->cmnd, 0, cmd->cmd_len);
+	memset(&cmd->sdb, 0, sizeof(cmd->sdb));
+	cmd->cmnd[0] = ZBC_OUT;
+	cmd->cmnd[1] = ZO_OPEN_ZONE;
+	if (rq->cmd_flags & REQ_CLOSE_ZONE)
+		cmd->cmnd[1] = ZO_CLOSE_ZONE;
+	if (rq->cmd_flags & REQ_RESET_ZONE)
+		cmd->cmnd[1] = ZO_RESET_WRITE_POINTER;
+	cmd->cmnd[14] = allbit;
+	put_unaligned_be64(sector, &cmd->cmnd[2]);
+	cmd->transfersize = 0;
+	cmd->underflow = 0;
+	cmd->allowed = SD_MAX_RETRIES;
+	cmd->sc_data_direction = DMA_NONE;
+
+	ret = BLKPREP_OK;
+out:
+	return ret;
+}
+
 static int sd_init_command(struct scsi_cmnd *cmd)
 {
 	struct request *rq = cmd->request;
 
-	if (rq->cmd_flags & REQ_DISCARD)
+	if (rq->cmd_flags & REQ_ZONED_CMDS)
+		return sd_setup_zoned_cmnd(cmd);
+	else if (rq->cmd_flags & REQ_DISCARD)
 		return sd_setup_discard_cmnd(cmd);
 	else if (rq->cmd_flags & REQ_WRITE_SAME)
 		return sd_setup_write_same_cmnd(cmd);
@@ -2732,6 +2827,8 @@  static void sd_read_block_characteristics(struct scsi_disk *sdkp)
 		queue_flag_clear_unlocked(QUEUE_FLAG_ADD_RANDOM, sdkp->disk->queue);
 	}
 
+	sdkp->zoned = (buffer[8] >> 4) & 3;
+
  out:
 	kfree(buffer);
 }
diff --git a/drivers/scsi/sd.h b/drivers/scsi/sd.h
index 654630b..e012175 100644
--- a/drivers/scsi/sd.h
+++ b/drivers/scsi/sd.h
@@ -94,6 +94,7 @@  struct scsi_disk {
 	unsigned	lbpvpd : 1;
 	unsigned	ws10 : 1;
 	unsigned	ws16 : 1;
+	unsigned	zoned: 2;
 };
 #define to_scsi_disk(obj) container_of(obj,struct scsi_disk,dev)
 
diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h
index 77e5d81..d2943e4 100644
--- a/include/linux/blk_types.h
+++ b/include/linux/blk_types.h
@@ -162,6 +162,10 @@  enum rq_flag_bits {
 	__REQ_FUA,		/* forced unit access */
 	__REQ_FLUSH,		/* request for cache flush */
 
+	__REQ_REPORT_ZONES,	/* Zoned device: Report Zones */
+	__REQ_OPEN_ZONE,	/* Zoned device: Open Zone */
+	__REQ_CLOSE_ZONE,	/* Zoned device: Close Zone */
+
 	/* bio only flags */
 	__REQ_RAHEAD,		/* read ahead, can fail anytime */
 	__REQ_THROTTLED,	/* This bio has already been subjected to
@@ -202,20 +206,27 @@  enum rq_flag_bits {
 #define REQ_WRITE_SAME		(1ULL << __REQ_WRITE_SAME)
 #define REQ_NOIDLE		(1ULL << __REQ_NOIDLE)
 #define REQ_INTEGRITY		(1ULL << __REQ_INTEGRITY)
+#define REQ_REPORT_ZONES	(1ULL << __REQ_REPORT_ZONES)
+#define REQ_OPEN_ZONE		(1ULL << __REQ_OPEN_ZONE)
+#define REQ_CLOSE_ZONE		(1ULL << __REQ_CLOSE_ZONE)
+#define REQ_RESET_ZONE		(REQ_REPORT_ZONES)
+#define REQ_ZONED_CMDS \
+	(REQ_OPEN_ZONE | REQ_CLOSE_ZONE | REQ_RESET_ZONE | REQ_REPORT_ZONES)
 
 #define REQ_FAILFAST_MASK \
 	(REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | REQ_FAILFAST_DRIVER)
 #define REQ_COMMON_MASK \
 	(REQ_WRITE | REQ_FAILFAST_MASK | REQ_SYNC | REQ_META | REQ_PRIO | \
 	 REQ_DISCARD | REQ_WRITE_SAME | REQ_NOIDLE | REQ_FLUSH | REQ_FUA | \
-	 REQ_SECURE | REQ_INTEGRITY | REQ_NOMERGE)
+	 REQ_SECURE | REQ_INTEGRITY | REQ_NOMERGE | REQ_ZONED_CMDS)
 #define REQ_CLONE_MASK		REQ_COMMON_MASK
-
-#define BIO_NO_ADVANCE_ITER_MASK	(REQ_DISCARD|REQ_WRITE_SAME)
+#define BIO_NO_ADVANCE_ITER_MASK \
+	(REQ_DISCARD | REQ_WRITE_SAME | REQ_ZONED_CMDS)
 
 /* This mask is used for both bio and request merge checking */
 #define REQ_NOMERGE_FLAGS \
-	(REQ_NOMERGE | REQ_STARTED | REQ_SOFTBARRIER | REQ_FLUSH | REQ_FUA | REQ_FLUSH_SEQ)
+	(REQ_NOMERGE | REQ_STARTED | REQ_SOFTBARRIER | \
+	 REQ_FLUSH | REQ_FUA | REQ_FLUSH_SEQ | REQ_ZONED_CMDS)
 
 #define REQ_RAHEAD		(1ULL << __REQ_RAHEAD)
 #define REQ_THROTTLED		(1ULL << __REQ_THROTTLED)
diff --git a/include/linux/blkzoned_api.h b/include/linux/blkzoned_api.h
new file mode 100644
index 0000000..9fc2373
--- /dev/null
+++ b/include/linux/blkzoned_api.h
@@ -0,0 +1,25 @@ 
+/*
+ * Functions for zone based SMR devices.
+ *
+ * Copyright (C) 2015 Seagate Technology PLC
+ *
+ * Written by:
+ * Shaun Tancheff <shaun.tancheff@seagate.com>
+ *
+ * This file is licensed under  the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#ifndef _BLKZONED_API_H
+#define _BLKZONED_API_H
+
+#include <uapi/linux/blkzoned_api.h>
+
+extern int blkdev_issue_zone_action(struct block_device *, unsigned int,
+				    sector_t, gfp_t);
+extern int blkdev_issue_zone_report(struct block_device *, unsigned int,
+				    sector_t, u8 opt, struct page *, size_t,
+				    gfp_t);
+
+#endif /* _BLKZONED_API_H */
diff --git a/include/uapi/linux/Kbuild b/include/uapi/linux/Kbuild
index 8bdae34..5152fa4 100644
--- a/include/uapi/linux/Kbuild
+++ b/include/uapi/linux/Kbuild
@@ -70,6 +70,7 @@  header-y += bfs_fs.h
 header-y += binfmts.h
 header-y += blkpg.h
 header-y += blktrace_api.h
+header-y += blkzoned_api.h
 header-y += bpf_common.h
 header-y += bpf.h
 header-y += bpqether.h
diff --git a/include/uapi/linux/blkzoned_api.h b/include/uapi/linux/blkzoned_api.h
new file mode 100644
index 0000000..189e925
--- /dev/null
+++ b/include/uapi/linux/blkzoned_api.h
@@ -0,0 +1,215 @@ 
+/*
+ * Functions for zone based SMR devices.
+ *
+ * Copyright (C) 2015 Seagate Technology PLC
+ *
+ * Written by:
+ * Shaun Tancheff <shaun.tancheff@seagate.com>
+ *
+ * This file is licensed under  the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#ifndef _UAPI_BLKZONED_API_H
+#define _UAPI_BLKZONED_API_H
+
+#include <linux/types.h>
+
+/**
+ * enum zone_report_option - Report Zones types to be included.
+ *
+ * @ZOPT_NON_SEQ_AND_RESET: Default (all zones).
+ * @ZOPT_ZC1_EMPTY: Zones which are empty.
+ * @ZOPT_ZC2_OPEN_IMPLICIT: Zones open but not explicitly opened
+ * @ZOPT_ZC3_OPEN_EXPLICIT: Zones opened explicitly
+ * @ZOPT_ZC4_CLOSED: Zones closed for writing.
+ * @ZOPT_ZC5_FULL: Zones that are full.
+ * @ZOPT_ZC6_READ_ONLY: Zones that are read-only
+ * @ZOPT_ZC7_OFFLINE: Zones that are offline
+ * @ZOPT_RESET: Zones that are empty
+ * @ZOPT_NON_SEQ: Zones that have HA media-cache writes pending
+ * @ZOPT_NON_WP_ZONES: Zones that do not have Write Pointers (conventional)
+ *
+ * @ZOPT_USE_ATA_PASS: Flag used in kernel to service command I/O
+ *
+ * Used by Report Zones in bdev_zone_get_report: report_option
+ */
+enum zone_report_option {
+	ZOPT_NON_SEQ_AND_RESET   = 0x00,
+	ZOPT_ZC1_EMPTY,
+	ZOPT_ZC2_OPEN_IMPLICIT,
+	ZOPT_ZC3_OPEN_EXPLICIT,
+	ZOPT_ZC4_CLOSED,
+	ZOPT_ZC5_FULL,
+	ZOPT_ZC6_READ_ONLY,
+	ZOPT_ZC7_OFFLINE,
+	ZOPT_RESET               = 0x10,
+	ZOPT_NON_SEQ             = 0x11,
+	ZOPT_NON_WP_ZONES        = 0x3f,
+	ZOPT_USE_ATA_PASS        = 0x80,
+};
+
+/**
+ * enum bdev_zone_type - Type of zone in descriptor
+ *
+ * @ZTYP_RESERVED: Reserved
+ * @ZTYP_CONVENTIONAL: Conventional random write zone (No Write Pointer)
+ * @ZTYP_SEQ_WRITE_REQUIRED: Non-sequential writes are rejected.
+ * @ZTYP_SEQ_WRITE_PREFERRED: Non-sequential writes allowed but discouraged.
+ *
+ * Returned from Report Zones. See bdev_zone_descriptor* type.
+ */
+enum bdev_zone_type {
+	ZTYP_RESERVED            = 0,
+	ZTYP_CONVENTIONAL        = 1,
+	ZTYP_SEQ_WRITE_REQUIRED  = 2,
+	ZTYP_SEQ_WRITE_PREFERRED = 3,
+};
+
+
+/**
+ * enum bdev_zone_condition - Condition of zone in descriptor
+ *
+ * @ZCOND_CONVENTIONAL: N/A
+ * @ZCOND_ZC1_EMPTY: Empty
+ * @ZCOND_ZC2_OPEN_IMPLICIT: Opened via write to zone.
+ * @ZCOND_ZC3_OPEN_EXPLICIT: Opened via open zone command.
+ * @ZCOND_ZC4_CLOSED: Closed
+ * @ZCOND_ZC6_READ_ONLY:
+ * @ZCOND_ZC5_FULL: No remaining space in zone.
+ * @ZCOND_ZC7_OFFLINE: Offline
+ *
+ * Returned from Report Zones. See bdev_zone_descriptor* flags.
+ */
+enum bdev_zone_condition {
+	ZCOND_CONVENTIONAL       = 0,
+	ZCOND_ZC1_EMPTY          = 1,
+	ZCOND_ZC2_OPEN_IMPLICIT  = 2,
+	ZCOND_ZC3_OPEN_EXPLICIT  = 3,
+	ZCOND_ZC4_CLOSED         = 4,
+	/* 0x5 to 0xC are reserved */
+	ZCOND_ZC6_READ_ONLY      = 0xd,
+	ZCOND_ZC5_FULL           = 0xe,
+	ZCOND_ZC7_OFFLINE        = 0xf,
+};
+
+
+/**
+ * enum bdev_zone_same - Report Zones same code.
+ *
+ * @ZS_ALL_DIFFERENT: All zones differ in type and size.
+ * @ZS_ALL_SAME: All zones are the same size and type.
+ * @ZS_LAST_DIFFERS: All zones are the same size and type except the last zone.
+ * @ZS_SAME_LEN_DIFF_TYPES: All zones are the same length but types differ.
+ *
+ * Returned from Report Zones. See bdev_zone_report* same_field.
+ */
+enum bdev_zone_same {
+	ZS_ALL_DIFFERENT        = 0,
+	ZS_ALL_SAME             = 1,
+	ZS_LAST_DIFFERS         = 2,
+	ZS_SAME_LEN_DIFF_TYPES  = 3,
+};
+
+
+/**
+ * struct bdev_zone_get_report - ioctl: Report Zones request
+ *
+ * @zone_locator_lba: starting lba for first [reported] zone
+ * @return_page_count: number of *bytes* allocated for result
+ * @report_option: see: zone_report_option enum
+ *
+ * Used to issue report zones command to connected device
+ */
+struct bdev_zone_get_report {
+	__u64 zone_locator_lba;
+	__u32 return_page_count;
+	__u8  report_option;
+} __packed;
+
+/**
+ * struct bdev_zone_descriptor_le - See: bdev_zone_descriptor
+ */
+struct bdev_zone_descriptor_le {
+	__u8 type;
+	__u8 flags;
+	__u8 reserved1[6];
+	__le64 length;
+	__le64 lba_start;
+	__le64 lba_wptr;
+	__u8 reserved[32];
+} __packed;
+
+
+/**
+ * struct bdev_zone_report_le - See: bdev_zone_report
+ */
+struct bdev_zone_report_le {
+	__le32 descriptor_count;
+	__u8 same_field;
+	__u8 reserved1[3];
+	__le64 maximum_lba;
+	__u8 reserved2[48];
+	struct bdev_zone_descriptor_le descriptors[0];
+} __packed;
+
+
+/**
+ * struct bdev_zone_descriptor - A Zone descriptor entry from report zones
+ *
+ * @type: see zone_type enum
+ * @flags: Bits 0:reset, 1:non-seq, 2-3: resv, 4-7: see zone_condition enum
+ * @reserved1: padding
+ * @length: length of zone in sectors
+ * @lba_start: lba where the zone starts.
+ * @lba_wptr: lba of the current write pointer.
+ * @reserved: padding
+ *
+ */
+struct bdev_zone_descriptor {
+	__u8 type;
+	__u8 flags;
+	__u8  reserved1[6];
+	__be64 length;
+	__be64 lba_start;
+	__be64 lba_wptr;
+	__u8 reserved[32];
+} __packed;
+
+
+/**
+ * struct bdev_zone_report - Report Zones result
+ *
+ * @descriptor_count: Number of descriptor entries that follow
+ * @same_field: bits 0-3: enum zone_same (MASK: 0x0F)
+ * @reserved1: padding
+ * @maximum_lba: LBA of the last logical sector on the device, inclusive
+ *               of all logical sectors in all zones.
+ * @reserved2: padding
+ * @descriptors: array of descriptors follows.
+ */
+struct bdev_zone_report {
+	__be32 descriptor_count;
+	__u8 same_field;
+	__u8 reserved1[3];
+	__be64 maximum_lba;
+	__u8 reserved2[48];
+	struct bdev_zone_descriptor descriptors[0];
+} __packed;
+
+
+/**
+ * struct bdev_zone_report_io - Report Zones ioctl argument.
+ *
+ * @in: Report Zones inputs
+ * @out: Report Zones output
+ */
+struct bdev_zone_report_io {
+	union {
+		struct bdev_zone_get_report in;
+		struct bdev_zone_report out;
+	} data;
+} __packed;
+
+#endif /* _UAPI_BLKZONED_API_H */