Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
diff --git a/drivers/s390/char/tape_block.c b/drivers/s390/char/tape_block.c
new file mode 100644
index 0000000..1efc9f2
--- /dev/null
+++ b/drivers/s390/char/tape_block.c
@@ -0,0 +1,492 @@
+/*
+ * drivers/s390/char/tape_block.c
+ * block device frontend for tape device driver
+ *
+ * S390 and zSeries version
+ * Copyright (C) 2001,2003 IBM Deutschland Entwicklung GmbH, IBM Corporation
+ * Author(s): Carsten Otte <cotte@de.ibm.com>
+ * Tuan Ngo-Anh <ngoanh@de.ibm.com>
+ * Martin Schwidefsky <schwidefsky@de.ibm.com>
+ * Stefan Bader <shbader@de.ibm.com>
+ */
+
+#include <linux/fs.h>
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/blkdev.h>
+#include <linux/interrupt.h>
+#include <linux/buffer_head.h>
+
+#include <asm/debug.h>
+
+#define TAPE_DBF_AREA tape_core_dbf
+
+#include "tape.h"
+
+#define PRINTK_HEADER "TAPE_BLOCK: "
+
+#define TAPEBLOCK_MAX_SEC 100
+#define TAPEBLOCK_MIN_REQUEUE 3
+
+/*
+ * 2003/11/25 Stefan Bader <shbader@de.ibm.com>
+ *
+ * In 2.5/2.6 the block device request function is very likely to be called
+ * with disabled interrupts (e.g. generic_unplug_device). So the driver can't
+ * just call any function that tries to allocate CCW requests from that con-
+ * text since it might sleep. There are two choices to work around this:
+ * a) do not allocate with kmalloc but use its own memory pool
+ * b) take requests from the queue outside that context, knowing that
+ * allocation might sleep
+ */
+
+/*
+ * file operation structure for tape block frontend
+ */
+static int tapeblock_open(struct inode *, struct file *);
+static int tapeblock_release(struct inode *, struct file *);
+static int tapeblock_ioctl(struct inode *, struct file *, unsigned int,
+ unsigned long);
+static int tapeblock_medium_changed(struct gendisk *);
+static int tapeblock_revalidate_disk(struct gendisk *);
+
+static struct block_device_operations tapeblock_fops = {
+ .owner = THIS_MODULE,
+ .open = tapeblock_open,
+ .release = tapeblock_release,
+ .ioctl = tapeblock_ioctl,
+ .media_changed = tapeblock_medium_changed,
+ .revalidate_disk = tapeblock_revalidate_disk,
+};
+
+static int tapeblock_major = 0;
+
+static void
+tapeblock_trigger_requeue(struct tape_device *device)
+{
+ /* Protect against rescheduling. */
+ if (atomic_compare_and_swap(0, 1, &device->blk_data.requeue_scheduled))
+ return;
+ schedule_work(&device->blk_data.requeue_task);
+}
+
+/*
+ * Post finished request.
+ */
+static inline void
+tapeblock_end_request(struct request *req, int uptodate)
+{
+ if (end_that_request_first(req, uptodate, req->hard_nr_sectors))
+ BUG();
+ end_that_request_last(req);
+}
+
+static void
+__tapeblock_end_request(struct tape_request *ccw_req, void *data)
+{
+ struct tape_device *device;
+ struct request *req;
+
+ DBF_LH(6, "__tapeblock_end_request()\n");
+
+ device = ccw_req->device;
+ req = (struct request *) data;
+ tapeblock_end_request(req, ccw_req->rc == 0);
+ if (ccw_req->rc == 0)
+ /* Update position. */
+ device->blk_data.block_position =
+ (req->sector + req->nr_sectors) >> TAPEBLOCK_HSEC_S2B;
+ else
+ /* We lost the position information due to an error. */
+ device->blk_data.block_position = -1;
+ device->discipline->free_bread(ccw_req);
+ if (!list_empty(&device->req_queue) ||
+ elv_next_request(device->blk_data.request_queue))
+ tapeblock_trigger_requeue(device);
+}
+
+/*
+ * Feed the tape device CCW queue with requests supplied in a list.
+ */
+static inline int
+tapeblock_start_request(struct tape_device *device, struct request *req)
+{
+ struct tape_request * ccw_req;
+ int rc;
+
+ DBF_LH(6, "tapeblock_start_request(%p, %p)\n", device, req);
+
+ ccw_req = device->discipline->bread(device, req);
+ if (IS_ERR(ccw_req)) {
+ DBF_EVENT(1, "TBLOCK: bread failed\n");
+ tapeblock_end_request(req, 0);
+ return PTR_ERR(ccw_req);
+ }
+ ccw_req->callback = __tapeblock_end_request;
+ ccw_req->callback_data = (void *) req;
+ ccw_req->retries = TAPEBLOCK_RETRIES;
+
+ rc = tape_do_io_async(device, ccw_req);
+ if (rc) {
+ /*
+ * Start/enqueueing failed. No retries in
+ * this case.
+ */
+ tapeblock_end_request(req, 0);
+ device->discipline->free_bread(ccw_req);
+ }
+
+ return rc;
+}
+
+/*
+ * Move requests from the block device request queue to the tape device ccw
+ * queue.
+ */
+static void
+tapeblock_requeue(void *data) {
+ struct tape_device * device;
+ request_queue_t * queue;
+ int nr_queued;
+ struct request * req;
+ struct list_head * l;
+ int rc;
+
+ device = (struct tape_device *) data;
+ if (!device)
+ return;
+
+ spin_lock_irq(get_ccwdev_lock(device->cdev));
+ queue = device->blk_data.request_queue;
+
+ /* Count number of requests on ccw queue. */
+ nr_queued = 0;
+ list_for_each(l, &device->req_queue)
+ nr_queued++;
+ spin_unlock(get_ccwdev_lock(device->cdev));
+
+ spin_lock(&device->blk_data.request_queue_lock);
+ while (
+ !blk_queue_plugged(queue) &&
+ elv_next_request(queue) &&
+ nr_queued < TAPEBLOCK_MIN_REQUEUE
+ ) {
+ req = elv_next_request(queue);
+ if (rq_data_dir(req) == WRITE) {
+ DBF_EVENT(1, "TBLOCK: Rejecting write request\n");
+ blkdev_dequeue_request(req);
+ tapeblock_end_request(req, 0);
+ continue;
+ }
+ spin_unlock_irq(&device->blk_data.request_queue_lock);
+ rc = tapeblock_start_request(device, req);
+ spin_lock_irq(&device->blk_data.request_queue_lock);
+ blkdev_dequeue_request(req);
+ nr_queued++;
+ }
+ spin_unlock_irq(&device->blk_data.request_queue_lock);
+ atomic_set(&device->blk_data.requeue_scheduled, 0);
+}
+
+/*
+ * Tape request queue function. Called from ll_rw_blk.c
+ */
+static void
+tapeblock_request_fn(request_queue_t *queue)
+{
+ struct tape_device *device;
+
+ device = (struct tape_device *) queue->queuedata;
+ DBF_LH(6, "tapeblock_request_fn(device=%p)\n", device);
+ if (device == NULL)
+ BUG();
+
+ tapeblock_trigger_requeue(device);
+}
+
+/*
+ * This function is called for every new tapedevice
+ */
+int
+tapeblock_setup_device(struct tape_device * device)
+{
+ struct tape_blk_data * blkdat;
+ struct gendisk * disk;
+ int rc;
+
+ blkdat = &device->blk_data;
+ spin_lock_init(&blkdat->request_queue_lock);
+ atomic_set(&blkdat->requeue_scheduled, 0);
+
+ blkdat->request_queue = blk_init_queue(
+ tapeblock_request_fn,
+ &blkdat->request_queue_lock
+ );
+ if (!blkdat->request_queue)
+ return -ENOMEM;
+
+ elevator_exit(blkdat->request_queue->elevator);
+ rc = elevator_init(blkdat->request_queue, "noop");
+ if (rc)
+ goto cleanup_queue;
+
+ blk_queue_hardsect_size(blkdat->request_queue, TAPEBLOCK_HSEC_SIZE);
+ blk_queue_max_sectors(blkdat->request_queue, TAPEBLOCK_MAX_SEC);
+ blk_queue_max_phys_segments(blkdat->request_queue, -1L);
+ blk_queue_max_hw_segments(blkdat->request_queue, -1L);
+ blk_queue_max_segment_size(blkdat->request_queue, -1L);
+ blk_queue_segment_boundary(blkdat->request_queue, -1L);
+
+ disk = alloc_disk(1);
+ if (!disk) {
+ rc = -ENOMEM;
+ goto cleanup_queue;
+ }
+
+ disk->major = tapeblock_major;
+ disk->first_minor = device->first_minor;
+ disk->fops = &tapeblock_fops;
+ disk->private_data = tape_get_device_reference(device);
+ disk->queue = blkdat->request_queue;
+ set_capacity(disk, 0);
+ sprintf(disk->disk_name, "btibm%d",
+ device->first_minor / TAPE_MINORS_PER_DEV);
+
+ blkdat->disk = disk;
+ blkdat->medium_changed = 1;
+ blkdat->request_queue->queuedata = tape_get_device_reference(device);
+
+ add_disk(disk);
+
+ INIT_WORK(&blkdat->requeue_task, tapeblock_requeue,
+ tape_get_device_reference(device));
+
+ return 0;
+
+cleanup_queue:
+ blk_cleanup_queue(blkdat->request_queue);
+ blkdat->request_queue = NULL;
+
+ return rc;
+}
+
+void
+tapeblock_cleanup_device(struct tape_device *device)
+{
+ flush_scheduled_work();
+ device->blk_data.requeue_task.data = tape_put_device(device);
+
+ if (!device->blk_data.disk) {
+ PRINT_ERR("(%s): No gendisk to clean up!\n",
+ device->cdev->dev.bus_id);
+ goto cleanup_queue;
+ }
+
+ del_gendisk(device->blk_data.disk);
+ device->blk_data.disk->private_data =
+ tape_put_device(device->blk_data.disk->private_data);
+ put_disk(device->blk_data.disk);
+
+ device->blk_data.disk = NULL;
+cleanup_queue:
+ device->blk_data.request_queue->queuedata = tape_put_device(device);
+
+ blk_cleanup_queue(device->blk_data.request_queue);
+ device->blk_data.request_queue = NULL;
+}
+
+/*
+ * Detect number of blocks of the tape.
+ * FIXME: can we extent this to detect the blocks size as well ?
+ */
+static int
+tapeblock_revalidate_disk(struct gendisk *disk)
+{
+ struct tape_device * device;
+ unsigned int nr_of_blks;
+ int rc;
+
+ device = (struct tape_device *) disk->private_data;
+ if (!device)
+ BUG();
+
+ if (!device->blk_data.medium_changed)
+ return 0;
+
+ PRINT_INFO("Detecting media size...\n");
+ rc = tape_mtop(device, MTFSFM, 1);
+ if (rc)
+ return rc;
+
+ rc = tape_mtop(device, MTTELL, 1);
+ if (rc < 0)
+ return rc;
+
+ DBF_LH(3, "Image file ends at %d\n", rc);
+ nr_of_blks = rc;
+
+ /* This will fail for the first file. Catch the error by checking the
+ * position. */
+ tape_mtop(device, MTBSF, 1);
+
+ rc = tape_mtop(device, MTTELL, 1);
+ if (rc < 0)
+ return rc;
+
+ if (rc > nr_of_blks)
+ return -EINVAL;
+
+ DBF_LH(3, "Image file starts at %d\n", rc);
+ device->bof = rc;
+ nr_of_blks -= rc;
+
+ PRINT_INFO("Found %i blocks on media\n", nr_of_blks);
+ set_capacity(device->blk_data.disk,
+ nr_of_blks*(TAPEBLOCK_HSEC_SIZE/512));
+
+ device->blk_data.block_position = 0;
+ device->blk_data.medium_changed = 0;
+ return 0;
+}
+
+static int
+tapeblock_medium_changed(struct gendisk *disk)
+{
+ struct tape_device *device;
+
+ device = (struct tape_device *) disk->private_data;
+ DBF_LH(6, "tapeblock_medium_changed(%p) = %d\n",
+ device, device->blk_data.medium_changed);
+
+ return device->blk_data.medium_changed;
+}
+
+/*
+ * Block frontend tape device open function.
+ */
+static int
+tapeblock_open(struct inode *inode, struct file *filp)
+{
+ struct gendisk * disk;
+ struct tape_device * device;
+ int rc;
+
+ disk = inode->i_bdev->bd_disk;
+ device = tape_get_device_reference(disk->private_data);
+
+ if (device->required_tapemarks) {
+ DBF_EVENT(2, "TBLOCK: missing tapemarks\n");
+ PRINT_ERR("TBLOCK: Refusing to open tape with missing"
+ " end of file marks.\n");
+ rc = -EPERM;
+ goto put_device;
+ }
+
+ rc = tape_open(device);
+ if (rc)
+ goto put_device;
+
+ rc = tapeblock_revalidate_disk(disk);
+ if (rc)
+ goto release;
+
+ /*
+ * Note: The reference to <device> is hold until the release function
+ * is called.
+ */
+ tape_state_set(device, TS_BLKUSE);
+ return 0;
+
+release:
+ tape_release(device);
+ put_device:
+ tape_put_device(device);
+ return rc;
+}
+
+/*
+ * Block frontend tape device release function.
+ *
+ * Note: One reference to the tape device was made by the open function. So
+ * we just get the pointer here and release the reference.
+ */
+static int
+tapeblock_release(struct inode *inode, struct file *filp)
+{
+ struct gendisk *disk = inode->i_bdev->bd_disk;
+ struct tape_device *device = disk->private_data;
+
+ tape_state_set(device, TS_IN_USE);
+ tape_release(device);
+ tape_put_device(device);
+
+ return 0;
+}
+
+/*
+ * Support of some generic block device IOCTLs.
+ */
+static int
+tapeblock_ioctl(
+ struct inode * inode,
+ struct file * file,
+ unsigned int command,
+ unsigned long arg
+) {
+ int rc;
+ int minor;
+ struct gendisk *disk = inode->i_bdev->bd_disk;
+ struct tape_device *device = disk->private_data;
+
+ rc = 0;
+ disk = inode->i_bdev->bd_disk;
+ if (!disk)
+ BUG();
+ device = disk->private_data;
+ if (!device)
+ BUG();
+ minor = iminor(inode);
+
+ DBF_LH(6, "tapeblock_ioctl(0x%0x)\n", command);
+ DBF_LH(6, "device = %d:%d\n", tapeblock_major, minor);
+
+ switch (command) {
+ /* Refuse some IOCTL calls without complaining (mount). */
+ case 0x5310: /* CDROMMULTISESSION */
+ rc = -EINVAL;
+ break;
+ default:
+ PRINT_WARN("invalid ioctl 0x%x\n", command);
+ rc = -EINVAL;
+ }
+
+ return rc;
+}
+
+/*
+ * Initialize block device frontend.
+ */
+int
+tapeblock_init(void)
+{
+ int rc;
+
+ /* Register the tape major number to the kernel */
+ rc = register_blkdev(tapeblock_major, "tBLK");
+ if (rc < 0)
+ return rc;
+
+ if (tapeblock_major == 0)
+ tapeblock_major = rc;
+ PRINT_INFO("tape gets major %d for block device\n", tapeblock_major);
+ return 0;
+}
+
+/*
+ * Deregister major for block device frontend
+ */
+void
+tapeblock_exit(void)
+{
+ unregister_blkdev(tapeblock_major, "tBLK");
+}