ps3: Disk Storage Driver

Add a Disk Storage Driver for the PS3:
  - Implemented as a block device driver with a dynamic major
  - Disk names (and partitions) are of the format ps3d%c(%u)
  - Uses software scatter-gather with a 64 KiB bounce buffer as the hypervisor
    doesn't support scatter-gather

Cc: Geoff Levand <geoffrey.levand@am.sony.com>
Signed-off-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Acked-by: Jens Axboe <jens.axboe@oracle.com>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2 files changed, 631 insertions, 0 deletions

diff --git a/drivers/block/Makefile b/drivers/block/Makefile
index 819c829125fb..a7a099027fca 100644
--- a/drivers/block/Makefile
+++ b/drivers/block/Makefile
@@ -8,6 +8,7 @@
 obj-$(CONFIG_MAC_FLOPPY)	+= swim3.o
 obj-$(CONFIG_BLK_DEV_FD)	+= floppy.o
 obj-$(CONFIG_AMIGA_FLOPPY)	+= amiflop.o
+obj-$(CONFIG_PS3_DISK)		+= ps3disk.o
 obj-$(CONFIG_ATARI_FLOPPY)	+= ataflop.o
 obj-$(CONFIG_AMIGA_Z2RAM)	+= z2ram.o
 obj-$(CONFIG_BLK_DEV_RAM)	+= rd.o
diff --git a/drivers/block/ps3disk.c b/drivers/block/ps3disk.c
new file mode 100644
index 000000000000..170fb33dba97
--- /dev/null
+++ b/drivers/block/ps3disk.c
@@ -0,0 +1,630 @@
+/*
+ * PS3 Disk Storage Driver
+ *
+ * Copyright (C) 2007 Sony Computer Entertainment Inc.
+ * Copyright 2007 Sony Corp.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <linux/ata.h>
+#include <linux/blkdev.h>
+
+#include <asm/lv1call.h>
+#include <asm/ps3stor.h>
+#include <asm/firmware.h>
+
+
+#define DEVICE_NAME		"ps3disk"
+
+#define BOUNCE_SIZE		(64*1024)
+
+#define PS3DISK_MAX_DISKS	16
+#define PS3DISK_MINORS		16
+
+
+#define PS3DISK_NAME		"ps3d%c"
+
+
+struct ps3disk_private {
+	spinlock_t lock;		/* Request queue spinlock */
+	struct request_queue *queue;
+	struct gendisk *gendisk;
+	unsigned int blocking_factor;
+	struct request *req;
+	u64 raw_capacity;
+	unsigned char model[ATA_ID_PROD_LEN+1];
+};
+
+
+#define LV1_STORAGE_SEND_ATA_COMMAND	(2)
+#define LV1_STORAGE_ATA_HDDOUT		(0x23)
+
+struct lv1_ata_cmnd_block {
+	u16	features;
+	u16	sector_count;
+	u16	LBA_low;
+	u16	LBA_mid;
+	u16	LBA_high;
+	u8	device;
+	u8	command;
+	u32	is_ext;
+	u32	proto;
+	u32	in_out;
+	u32	size;
+	u64	buffer;
+	u32	arglen;
+};
+
+enum lv1_ata_proto {
+	NON_DATA_PROTO     = 0,
+	PIO_DATA_IN_PROTO  = 1,
+	PIO_DATA_OUT_PROTO = 2,
+	DMA_PROTO = 3
+};
+
+enum lv1_ata_in_out {
+	DIR_WRITE = 0,			/* memory -> device */
+	DIR_READ = 1			/* device -> memory */
+};
+
+static int ps3disk_major;
+
+
+static struct block_device_operations ps3disk_fops = {
+	.owner		= THIS_MODULE,
+};
+
+
+static void ps3disk_scatter_gather(struct ps3_storage_device *dev,
+				   struct request *req, int gather)
+{
+	unsigned int offset = 0;
+	struct bio *bio;
+	sector_t sector;
+	struct bio_vec *bvec;
+	unsigned int i = 0, j;
+	size_t size;
+	void *buf;
+
+	rq_for_each_bio(bio, req) {
+		sector = bio->bi_sector;
+		dev_dbg(&dev->sbd.core,
+			"%s:%u: bio %u: %u segs %u sectors from %lu\n",
+			__func__, __LINE__, i, bio_segments(bio),
+			bio_sectors(bio), sector);
+		bio_for_each_segment(bvec, bio, j) {
+			size = bvec->bv_len;
+			buf = __bio_kmap_atomic(bio, j, KM_IRQ0);
+			if (gather)
+				memcpy(dev->bounce_buf+offset, buf, size);
+			else
+				memcpy(buf, dev->bounce_buf+offset, size);
+			offset += size;
+			flush_kernel_dcache_page(bio_iovec_idx(bio, j)->bv_page);
+			__bio_kunmap_atomic(bio, KM_IRQ0);
+		}
+		i++;
+	}
+}
+
+static int ps3disk_submit_request_sg(struct ps3_storage_device *dev,
+				     struct request *req)
+{
+	struct ps3disk_private *priv = dev->sbd.core.driver_data;
+	int write = rq_data_dir(req), res;
+	const char *op = write ? "write" : "read";
+	u64 start_sector, sectors;
+	unsigned int region_id = dev->regions[dev->region_idx].id;
+
+#ifdef DEBUG
+	unsigned int n = 0;
+	struct bio *bio;
+
+	rq_for_each_bio(bio, req)
+		n++;
+	dev_dbg(&dev->sbd.core,
+		"%s:%u: %s req has %u bios for %lu sectors %lu hard sectors\n",
+		__func__, __LINE__, op, n, req->nr_sectors,
+		req->hard_nr_sectors);
+#endif
+
+	start_sector = req->sector * priv->blocking_factor;
+	sectors = req->nr_sectors * priv->blocking_factor;
+	dev_dbg(&dev->sbd.core, "%s:%u: %s %lu sectors starting at %lu\n",
+		__func__, __LINE__, op, sectors, start_sector);
+
+	if (write) {
+		ps3disk_scatter_gather(dev, req, 1);
+
+		res = lv1_storage_write(dev->sbd.dev_id, region_id,
+					start_sector, sectors, 0,
+					dev->bounce_lpar, &dev->tag);
+	} else {
+		res = lv1_storage_read(dev->sbd.dev_id, region_id,
+				       start_sector, sectors, 0,
+				       dev->bounce_lpar, &dev->tag);
+	}
+	if (res) {
+		dev_err(&dev->sbd.core, "%s:%u: %s failed %d\n", __func__,
+			__LINE__, op, res);
+		end_request(req, 0);
+		return 0;
+	}
+
+	priv->req = req;
+	return 1;
+}
+
+static int ps3disk_submit_flush_request(struct ps3_storage_device *dev,
+					struct request *req)
+{
+	struct ps3disk_private *priv = dev->sbd.core.driver_data;
+	u64 res;
+
+	dev_dbg(&dev->sbd.core, "%s:%u: flush request\n", __func__, __LINE__);
+
+	res = lv1_storage_send_device_command(dev->sbd.dev_id,
+					      LV1_STORAGE_ATA_HDDOUT, 0, 0, 0,
+					      0, &dev->tag);
+	if (res) {
+		dev_err(&dev->sbd.core, "%s:%u: sync cache failed 0x%lx\n",
+			__func__, __LINE__, res);
+		end_request(req, 0);
+		return 0;
+	}
+
+	priv->req = req;
+	return 1;
+}
+
+static void ps3disk_do_request(struct ps3_storage_device *dev,
+			       request_queue_t *q)
+{
+	struct request *req;
+
+	dev_dbg(&dev->sbd.core, "%s:%u\n", __func__, __LINE__);
+
+	while ((req = elv_next_request(q))) {
+		if (blk_fs_request(req)) {
+			if (ps3disk_submit_request_sg(dev, req))
+				break;
+		} else if (req->cmd_type == REQ_TYPE_FLUSH) {
+			if (ps3disk_submit_flush_request(dev, req))
+				break;
+		} else {
+			blk_dump_rq_flags(req, DEVICE_NAME " bad request");
+			end_request(req, 0);
+			continue;
+		}
+	}
+}
+
+static void ps3disk_request(request_queue_t *q)
+{
+	struct ps3_storage_device *dev = q->queuedata;
+	struct ps3disk_private *priv = dev->sbd.core.driver_data;
+
+	if (priv->req) {
+		dev_dbg(&dev->sbd.core, "%s:%u busy\n", __func__, __LINE__);
+		return;
+	}
+
+	ps3disk_do_request(dev, q);
+}
+
+static irqreturn_t ps3disk_interrupt(int irq, void *data)
+{
+	struct ps3_storage_device *dev = data;
+	struct ps3disk_private *priv;
+	struct request *req;
+	int res, read, uptodate;
+	u64 tag, status;
+	unsigned long num_sectors;
+	const char *op;
+
+	res = lv1_storage_get_async_status(dev->sbd.dev_id, &tag, &status);
+
+	if (tag != dev->tag)
+		dev_err(&dev->sbd.core,
+			"%s:%u: tag mismatch, got %lx, expected %lx\n",
+			__func__, __LINE__, tag, dev->tag);
+
+	if (res) {
+		dev_err(&dev->sbd.core, "%s:%u: res=%d status=0x%lx\n",
+			__func__, __LINE__, res, status);
+		return IRQ_HANDLED;
+	}
+
+	priv = dev->sbd.core.driver_data;
+	req = priv->req;
+	if (!req) {
+		dev_dbg(&dev->sbd.core,
+			"%s:%u non-block layer request completed\n", __func__,
+			__LINE__);
+		dev->lv1_status = status;
+		complete(&dev->done);
+		return IRQ_HANDLED;
+	}
+
+	if (req->cmd_type == REQ_TYPE_FLUSH) {
+		read = 0;
+		num_sectors = req->hard_cur_sectors;
+		op = "flush";
+	} else {
+		read = !rq_data_dir(req);
+		num_sectors = req->nr_sectors;
+		op = read ? "read" : "write";
+	}
+	if (status) {
+		dev_dbg(&dev->sbd.core, "%s:%u: %s failed 0x%lx\n", __func__,
+			__LINE__, op, status);
+		uptodate = 0;
+	} else {
+		dev_dbg(&dev->sbd.core, "%s:%u: %s completed\n", __func__,
+			__LINE__, op);
+		uptodate = 1;
+		if (read)
+			ps3disk_scatter_gather(dev, req, 0);
+	}
+
+	spin_lock(&priv->lock);
+	if (!end_that_request_first(req, uptodate, num_sectors)) {
+		add_disk_randomness(req->rq_disk);
+		blkdev_dequeue_request(req);
+		end_that_request_last(req, uptodate);
+	}
+	priv->req = NULL;
+	ps3disk_do_request(dev, priv->queue);
+	spin_unlock(&priv->lock);
+
+	return IRQ_HANDLED;
+}
+
+static int ps3disk_sync_cache(struct ps3_storage_device *dev)
+{
+	u64 res;
+
+	dev_dbg(&dev->sbd.core, "%s:%u: sync cache\n", __func__, __LINE__);
+
+	res = ps3stor_send_command(dev, LV1_STORAGE_ATA_HDDOUT, 0, 0, 0, 0);
+	if (res) {
+		dev_err(&dev->sbd.core, "%s:%u: sync cache failed 0x%lx\n",
+			__func__, __LINE__, res);
+		return -EIO;
+	}
+	return 0;
+}
+
+
+/* ATA helpers copied from drivers/ata/libata-core.c */
+
+static void swap_buf_le16(u16 *buf, unsigned int buf_words)
+{
+#ifdef __BIG_ENDIAN
+	unsigned int i;
+
+	for (i = 0; i < buf_words; i++)
+		buf[i] = le16_to_cpu(buf[i]);
+#endif /* __BIG_ENDIAN */
+}
+
+static u64 ata_id_n_sectors(const u16 *id)
+{
+	if (ata_id_has_lba(id)) {
+		if (ata_id_has_lba48(id))
+			return ata_id_u64(id, 100);
+		else
+			return ata_id_u32(id, 60);
+	} else {
+		if (ata_id_current_chs_valid(id))
+			return ata_id_u32(id, 57);
+		else
+			return id[1] * id[3] * id[6];
+	}
+}
+
+static void ata_id_string(const u16 *id, unsigned char *s, unsigned int ofs,
+			  unsigned int len)
+{
+	unsigned int c;
+
+	while (len > 0) {
+		c = id[ofs] >> 8;
+		*s = c;
+		s++;
+
+		c = id[ofs] & 0xff;
+		*s = c;
+		s++;
+
+		ofs++;
+		len -= 2;
+	}
+}
+
+static void ata_id_c_string(const u16 *id, unsigned char *s, unsigned int ofs,
+			    unsigned int len)
+{
+	unsigned char *p;
+
+	WARN_ON(!(len & 1));
+
+	ata_id_string(id, s, ofs, len - 1);
+
+	p = s + strnlen(s, len - 1);
+	while (p > s && p[-1] == ' ')
+		p--;
+	*p = '\0';
+}
+
+static int ps3disk_identify(struct ps3_storage_device *dev)
+{
+	struct ps3disk_private *priv = dev->sbd.core.driver_data;
+	struct lv1_ata_cmnd_block ata_cmnd;
+	u16 *id = dev->bounce_buf;
+	u64 res;
+
+	dev_dbg(&dev->sbd.core, "%s:%u: identify disk\n", __func__, __LINE__);
+
+	memset(&ata_cmnd, 0, sizeof(struct lv1_ata_cmnd_block));
+	ata_cmnd.command = ATA_CMD_ID_ATA;
+	ata_cmnd.sector_count = 1;
+	ata_cmnd.size = ata_cmnd.arglen = ATA_ID_WORDS * 2;
+	ata_cmnd.buffer = dev->bounce_lpar;
+	ata_cmnd.proto = PIO_DATA_IN_PROTO;
+	ata_cmnd.in_out = DIR_READ;
+
+	res = ps3stor_send_command(dev, LV1_STORAGE_SEND_ATA_COMMAND,
+				   ps3_mm_phys_to_lpar(__pa(&ata_cmnd)),
+				   sizeof(ata_cmnd), ata_cmnd.buffer,
+				   ata_cmnd.arglen);
+	if (res) {
+		dev_err(&dev->sbd.core, "%s:%u: identify disk failed 0x%lx\n",
+			__func__, __LINE__, res);
+		return -EIO;
+	}
+
+	swap_buf_le16(id, ATA_ID_WORDS);
+
+	/* All we're interested in are raw capacity and model name */
+	priv->raw_capacity = ata_id_n_sectors(id);
+	ata_id_c_string(id, priv->model, ATA_ID_PROD, sizeof(priv->model));
+	return 0;
+}
+
+static void ps3disk_prepare_flush(request_queue_t *q, struct request *req)
+{
+	struct ps3_storage_device *dev = q->queuedata;
+
+	dev_dbg(&dev->sbd.core, "%s:%u\n", __func__, __LINE__);
+
+	memset(req->cmd, 0, sizeof(req->cmd));
+	req->cmd_type = REQ_TYPE_FLUSH;
+}
+
+static int ps3disk_issue_flush(request_queue_t *q, struct gendisk *gendisk,
+			       sector_t *sector)
+{
+	struct ps3_storage_device *dev = q->queuedata;
+	struct request *req;
+	int res;
+
+	dev_dbg(&dev->sbd.core, "%s:%u\n", __func__, __LINE__);
+
+	req = blk_get_request(q, WRITE, __GFP_WAIT);
+	ps3disk_prepare_flush(q, req);
+	res = blk_execute_rq(q, gendisk, req, 0);
+	if (res)
+		dev_err(&dev->sbd.core, "%s:%u: flush request failed %d\n",
+			__func__, __LINE__, res);
+	blk_put_request(req);
+	return res;
+}
+
+
+static unsigned long ps3disk_mask;
+
+static DEFINE_MUTEX(ps3disk_mask_mutex);
+
+static int __devinit ps3disk_probe(struct ps3_system_bus_device *_dev)
+{
+	struct ps3_storage_device *dev = to_ps3_storage_device(&_dev->core);
+	struct ps3disk_private *priv;
+	int error;
+	unsigned int devidx;
+	struct request_queue *queue;
+	struct gendisk *gendisk;
+
+	if (dev->blk_size < 512) {
+		dev_err(&dev->sbd.core,
+			"%s:%u: cannot handle block size %lu\n", __func__,
+			__LINE__, dev->blk_size);
+		return -EINVAL;
+	}
+
+	BUILD_BUG_ON(PS3DISK_MAX_DISKS > BITS_PER_LONG);
+	mutex_lock(&ps3disk_mask_mutex);
+	devidx = find_first_zero_bit(&ps3disk_mask, PS3DISK_MAX_DISKS);
+	if (devidx >= PS3DISK_MAX_DISKS) {
+		dev_err(&dev->sbd.core, "%s:%u: Too many disks\n", __func__,
+			__LINE__);
+		mutex_unlock(&ps3disk_mask_mutex);
+		return -ENOSPC;
+	}
+	__set_bit(devidx, &ps3disk_mask);
+	mutex_unlock(&ps3disk_mask_mutex);
+
+	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+	if (!priv) {
+		error = -ENOMEM;
+		goto fail;
+	}
+
+	dev->sbd.core.driver_data = priv;
+	spin_lock_init(&priv->lock);
+
+	dev->bounce_size = BOUNCE_SIZE;
+	dev->bounce_buf = kmalloc(BOUNCE_SIZE, GFP_DMA);
+	if (!dev->bounce_buf) {
+		error = -ENOMEM;
+		goto fail_free_priv;
+	}
+
+	error = ps3stor_setup(dev, ps3disk_interrupt);
+	if (error)
+		goto fail_free_bounce;
+
+	ps3disk_identify(dev);
+
+	queue = blk_init_queue(ps3disk_request, &priv->lock);
+	if (!queue) {
+		dev_err(&dev->sbd.core, "%s:%u: blk_init_queue failed\n",
+			__func__, __LINE__);
+		error = -ENOMEM;
+		goto fail_teardown;
+	}
+
+	priv->queue = queue;
+	queue->queuedata = dev;
+
+	blk_queue_bounce_limit(queue, BLK_BOUNCE_HIGH);
+
+	blk_queue_max_sectors(queue, dev->bounce_size >> 9);
+	blk_queue_segment_boundary(queue, -1UL);
+	blk_queue_dma_alignment(queue, dev->blk_size-1);
+	blk_queue_hardsect_size(queue, dev->blk_size);
+
+	blk_queue_issue_flush_fn(queue, ps3disk_issue_flush);
+	blk_queue_ordered(queue, QUEUE_ORDERED_DRAIN_FLUSH,
+			  ps3disk_prepare_flush);
+
+	blk_queue_max_phys_segments(queue, -1);
+	blk_queue_max_hw_segments(queue, -1);
+	blk_queue_max_segment_size(queue, dev->bounce_size);
+
+	gendisk = alloc_disk(PS3DISK_MINORS);
+	if (!gendisk) {
+		dev_err(&dev->sbd.core, "%s:%u: alloc_disk failed\n", __func__,
+			__LINE__);
+		error = -ENOMEM;
+		goto fail_cleanup_queue;
+	}
+
+	priv->gendisk = gendisk;
+	gendisk->major = ps3disk_major;
+	gendisk->first_minor = devidx * PS3DISK_MINORS;
+	gendisk->fops = &ps3disk_fops;
+	gendisk->queue = queue;
+	gendisk->private_data = dev;
+	gendisk->driverfs_dev = &dev->sbd.core;
+	snprintf(gendisk->disk_name, sizeof(gendisk->disk_name), PS3DISK_NAME,
+		 devidx+'a');
+	priv->blocking_factor = dev->blk_size >> 9;
+	set_capacity(gendisk,
+		     dev->regions[dev->region_idx].size*priv->blocking_factor);
+
+	dev_info(&dev->sbd.core,
+		 "%s is a %s (%lu MiB total, %lu MiB for OtherOS)\n",
+		 gendisk->disk_name, priv->model, priv->raw_capacity >> 11,
+		 get_capacity(gendisk) >> 11);
+
+	add_disk(gendisk);
+	return 0;
+
+fail_cleanup_queue:
+	blk_cleanup_queue(queue);
+fail_teardown:
+	ps3stor_teardown(dev);
+fail_free_bounce:
+	kfree(dev->bounce_buf);
+fail_free_priv:
+	kfree(priv);
+	dev->sbd.core.driver_data = NULL;
+fail:
+	mutex_lock(&ps3disk_mask_mutex);
+	__clear_bit(devidx, &ps3disk_mask);
+	mutex_unlock(&ps3disk_mask_mutex);
+	return error;
+}
+
+static int ps3disk_remove(struct ps3_system_bus_device *_dev)
+{
+	struct ps3_storage_device *dev = to_ps3_storage_device(&_dev->core);
+	struct ps3disk_private *priv = dev->sbd.core.driver_data;
+
+	mutex_lock(&ps3disk_mask_mutex);
+	__clear_bit(priv->gendisk->first_minor / PS3DISK_MINORS,
+		    &ps3disk_mask);
+	mutex_unlock(&ps3disk_mask_mutex);
+	del_gendisk(priv->gendisk);
+	blk_cleanup_queue(priv->queue);
+	put_disk(priv->gendisk);
+	dev_notice(&dev->sbd.core, "Synchronizing disk cache\n");
+	ps3disk_sync_cache(dev);
+	ps3stor_teardown(dev);
+	kfree(dev->bounce_buf);
+	kfree(priv);
+	dev->sbd.core.driver_data = NULL;
+	return 0;
+}
+
+static struct ps3_system_bus_driver ps3disk = {
+	.match_id	= PS3_MATCH_ID_STOR_DISK,
+	.core.name	= DEVICE_NAME,
+	.core.owner	= THIS_MODULE,
+	.probe		= ps3disk_probe,
+	.remove		= ps3disk_remove,
+	.shutdown	= ps3disk_remove,
+};
+
+
+static int __init ps3disk_init(void)
+{
+	int error;
+
+	if (!firmware_has_feature(FW_FEATURE_PS3_LV1))
+		return -ENODEV;
+
+	error = register_blkdev(0, DEVICE_NAME);
+	if (error <= 0) {
+		printk(KERN_ERR "%s:%u: register_blkdev failed %d\n", __func__,
+		       __LINE__, error);
+		return error;
+	}
+	ps3disk_major = error;
+
+	pr_info("%s:%u: registered block device major %d\n", __func__,
+		__LINE__, ps3disk_major);
+
+	error = ps3_system_bus_driver_register(&ps3disk);
+	if (error)
+		unregister_blkdev(ps3disk_major, DEVICE_NAME);
+
+	return error;
+}
+
+static void __exit ps3disk_exit(void)
+{
+	ps3_system_bus_driver_unregister(&ps3disk);
+	unregister_blkdev(ps3disk_major, DEVICE_NAME);
+}
+
+module_init(ps3disk_init);
+module_exit(ps3disk_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("PS3 Disk Storage Driver");
+MODULE_AUTHOR("Sony Corporation");
+MODULE_ALIAS(PS3_MODULE_ALIAS_STOR_DISK);