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);