From a48212cb65e09669ed243581556529681cebba0a Mon Sep 17 00:00:00 2001 From: "iap10@labyrinth.cl.cam.ac.uk" Date: Mon, 24 Feb 2003 16:55:07 +0000 Subject: bitkeeper revision 1.93 (3e5a4e6bkPheUp3x1uufN2MS3LAB7A) Latest and Greatest version of XenoLinux based on the Linux-2.4.21-pre4 kernel. --- .../arch/xeno/drivers/block/xl_block.c | 490 +++++++++++++++++++++ 1 file changed, 490 insertions(+) create mode 100644 xenolinux-2.4.21-pre4-sparse/arch/xeno/drivers/block/xl_block.c (limited to 'xenolinux-2.4.21-pre4-sparse/arch/xeno/drivers/block/xl_block.c') diff --git a/xenolinux-2.4.21-pre4-sparse/arch/xeno/drivers/block/xl_block.c b/xenolinux-2.4.21-pre4-sparse/arch/xeno/drivers/block/xl_block.c new file mode 100644 index 0000000000..0b77e5536e --- /dev/null +++ b/xenolinux-2.4.21-pre4-sparse/arch/xeno/drivers/block/xl_block.c @@ -0,0 +1,490 @@ +/****************************************************************************** + * xl_block.c + * + * Xenolinux virtual block-device driver. + * + */ + +#include +#include + +#include +#include +#include +#include +#include + +#include +#include +#include +#include + +#include +#include +#include +#include + +#define MAJOR_NR XLBLK_MAJOR /* force defns in blk.h, must precede include */ +static int xlblk_major = XLBLK_MAJOR; +#include + +/* Copied from linux/ide.h */ +typedef unsigned char byte; + +void xlblk_ide_register_disk(int, unsigned long); + +#define XLBLK_MAX 32 /* Maximum minor devices we support */ +#define XLBLK_MAJOR_NAME "xhd" +#define IDE_PARTN_BITS 6 /* from ide.h::PARTN_BITS */ +#define IDE_PARTN_MASK ((1<i_rdev); + if (minor_dev >= XLBLK_MAX) return -ENODEV; + + DPRINTK_IOCTL("command: 0x%x, argument: 0x%lx, minor: 0x%x\n", + command, (long) argument, minor_dev); + + switch (command) + { + case BLKGETSIZE: + DPRINTK_IOCTL(" BLKGETSIZE: %x %lx\n", BLKGETSIZE, + (long) xen_disk_info.disks[0].capacity); + return put_user(xen_disk_info.disks[0].capacity, + (unsigned long *) argument); + + case BLKRRPART: + DPRINTK_IOCTL(" BLKRRPART: %x\n", BLKRRPART); + break; + + case BLKSSZGET: + DPRINTK_IOCTL(" BLKSSZGET: %x 0x%x\n", BLKSSZGET, + xlblk_hardsect_size[minor_dev]); + return xlblk_hardsect_size[minor_dev]; + + case HDIO_GETGEO: + DPRINTK_IOCTL(" HDIO_GETGEO: %x\n", HDIO_GETGEO); + if (!argument) return -EINVAL; + if (put_user(0x00, (unsigned long *) &geo->start)) return -EFAULT; + if (put_user(0xff, (byte *)&geo->heads)) return -EFAULT; + if (put_user(0x3f, (byte *)&geo->sectors)) return -EFAULT; + if (put_user(0x106, (unsigned short *)&geo->cylinders)) return -EFAULT; + return 0; + + case HDIO_GETGEO_BIG: + DPRINTK_IOCTL(" HDIO_GETGEO_BIG: %x\n", HDIO_GETGEO_BIG); + if (!argument) return -EINVAL; + if (put_user(0x00, (unsigned long *) &geo->start)) return -EFAULT; + if (put_user(0xff, (byte *)&geo->heads)) return -EFAULT; + if (put_user(0x3f, (byte *)&geo->sectors)) return -EFAULT; + if (put_user(0x106, (unsigned int *) &geo->cylinders)) return -EFAULT; + + return 0; + + default: + DPRINTK_IOCTL(" eh? unknown ioctl\n"); + break; + } + + return 0; +} + +static int xenolinux_block_check(kdev_t dev) +{ + DPRINTK("xenolinux_block_check\n"); + return 0; +} + +static int xenolinux_block_revalidate(kdev_t dev) +{ + DPRINTK("xenolinux_block_revalidate\n"); + return 0; +} + +/* + * hypervisor_request + * + * request block io + * + * id: for guest use only. + * operation: XEN_BLOCK_READ, XEN_BLOCK_WRITE or XEN_BLOCK_PROBE + * buffer: buffer to read/write into. this should be a + * virtual address in the guest os. + * block_number: block to read + * block_size: size of each block + * device: ide/hda is 768 or 0x300 + */ +int hypervisor_request(void * id, + int operation, + char * buffer, + unsigned long block_number, + unsigned short block_size, + kdev_t device) +{ + int position; + void *buffer_ma; + kdev_t phys_device = (kdev_t) 0; + unsigned long sector_number = 0; + struct gendisk *gd; + + /* + * Bail if there's no room in the request communication ring. This may be + * because we have a whole bunch of outstanding responses to process. No + * matter, as the response handler will kick the request queue. + */ + if ( BLK_RING_INC(blk_ring->req_prod) == resp_cons ) + return 1; + + buffer_ma = (void *)phys_to_machine(virt_to_phys(buffer)); + + switch ( operation ) + { + case XEN_BLOCK_PROBE: + phys_device = (kdev_t) 0; + sector_number = 0; + break; + + case XEN_BLOCK_READ: + case XEN_BLOCK_WRITE: + if ( MAJOR(device) != XLBLK_MAJOR ) + panic("error: xl_block::hypervisor_request: " + "unknown device [0x%x]\n", device); + phys_device = MKDEV(IDE0_MAJOR, 0); + /* Compute real buffer location on disk */ + sector_number = block_number; + if ( (gd = (struct gendisk *)xen_disk_info.disks[0].gendisk) != NULL ) + sector_number += gd->part[MINOR(device)&IDE_PARTN_MASK].start_sect; + break; + + default: + panic("unknown op %d\n", operation); + } + + /* Fill out a communications ring structure & trap to the hypervisor */ + position = blk_ring->req_prod; + blk_ring->ring[position].req.id = id; + blk_ring->ring[position].req.operation = operation; + blk_ring->ring[position].req.buffer = buffer_ma; + blk_ring->ring[position].req.block_number = block_number; + blk_ring->ring[position].req.block_size = block_size; + blk_ring->ring[position].req.device = phys_device; + blk_ring->ring[position].req.sector_number = sector_number; + + blk_ring->req_prod = BLK_RING_INC(position); + + return 0; +} + + +/* + * do_xlblk_request + * read a block; request is in a request queue + */ +static void do_xlblk_request (request_queue_t *rq) +{ + struct request *req; + struct buffer_head *bh; + int rw, nsect, full, queued = 0; + + DPRINTK("xlblk.c::do_xlblk_request for '%s'\n", DEVICE_NAME); + + while ( !rq->plugged && !QUEUE_EMPTY ) + { + if ( (req = CURRENT) == NULL ) goto out; + + DPRINTK("do_xlblk_request %p: cmd %i, sec %lx, (%li/%li) bh:%p\n", + req, req->cmd, req->sector, + req->current_nr_sectors, req->nr_sectors, req->bh); + + rw = req->cmd; + if ( rw == READA ) rw = READ; + if ((rw != READ) && (rw != WRITE)) + panic("XenoLinux Virtual Block Device: bad cmd: %d\n", rw); + + req->errors = 0; + + bh = req->bh; + while ( bh != NULL ) + { + full = hypervisor_request( + bh, (rw == READ) ? XEN_BLOCK_READ : XEN_BLOCK_WRITE, + bh->b_data, bh->b_rsector, bh->b_size, bh->b_dev); + + if ( full ) goto out; + + queued++; + + /* Dequeue the buffer head from the request. */ + nsect = bh->b_size >> 9; + req->bh = bh->b_reqnext; + bh->b_reqnext = NULL; + bh = req->bh; + + if ( bh != NULL ) + { + /* There's another buffer head to do. Update the request. */ + req->hard_sector += nsect; + req->hard_nr_sectors -= nsect; + req->sector = req->hard_sector; + req->nr_sectors = req->hard_nr_sectors; + req->current_nr_sectors = bh->b_size >> 9; + req->buffer = bh->b_data; + } + else + { + /* That was the last buffer head. Finalise the request. */ + if ( end_that_request_first(req, 1, "XenBlk") ) BUG(); + blkdev_dequeue_request(req); + end_that_request_last(req); + } + } + } + + out: + if ( queued != 0 ) HYPERVISOR_block_io_op(); +} + + +static struct block_device_operations xenolinux_block_fops = +{ + open: xenolinux_block_open, + release: xenolinux_block_release, + ioctl: xenolinux_block_ioctl, + check_media_change: xenolinux_block_check, + revalidate: xenolinux_block_revalidate, +}; + +static void xlblk_response_int(int irq, void *dev_id, struct pt_regs *ptregs) +{ + int i; + unsigned long flags; + struct buffer_head *bh; + + spin_lock_irqsave(&io_request_lock, flags); + + for ( i = resp_cons; + i != blk_ring->resp_prod; + i = BLK_RING_INC(i) ) + { + blk_ring_resp_entry_t *bret = &blk_ring->ring[i].resp; + if ( (bh = bret->id) != NULL ) bh->b_end_io(bh, 1); + } + + resp_cons = i; + + /* KAF: We can push work down at this point. We have the lock. */ + do_xlblk_request(BLK_DEFAULT_QUEUE(MAJOR_NR)); + + spin_unlock_irqrestore(&io_request_lock, flags); +} + + +int __init xlblk_init(void) +{ + int i, error, result; + + /* This mapping was created early at boot time. */ + blk_ring = (blk_ring_t *)fix_to_virt(FIX_BLKRING_BASE); + blk_ring->req_prod = blk_ring->resp_prod = resp_cons = 0; + + error = request_irq(XLBLK_RESPONSE_IRQ, xlblk_response_int, 0, + "xlblk-response", NULL); + if (error) { + printk(KERN_ALERT "Could not allocate receive interrupt\n"); + goto fail; + } + + memset (&xen_disk_info, 0, sizeof(xen_disk_info)); + xen_disk_info.count = 0; + + if ( hypervisor_request(NULL, XEN_BLOCK_PROBE, (char *) &xen_disk_info, + 0, 0, (kdev_t) 0) ) + BUG(); + HYPERVISOR_block_io_op(); + while ( blk_ring->resp_prod != 1 ) barrier(); + for ( i = 0; i < xen_disk_info.count; i++ ) + { + printk (KERN_ALERT " %2d: type: %d, capacity: %ld\n", + i, xen_disk_info.disks[i].type, + xen_disk_info.disks[i].capacity); + } + + SET_MODULE_OWNER(&xenolinux_block_fops); + result = register_blkdev(xlblk_major, "block", &xenolinux_block_fops); + if (result < 0) { + printk (KERN_ALERT "xenolinux block: can't get major %d\n", + xlblk_major); + return result; + } + + /* initialize global arrays in drivers/block/ll_rw_block.c */ + for (i = 0; i < XLBLK_MAX; i++) { + xlblk_blk_size[i] = xen_disk_info.disks[0].capacity; + xlblk_blksize_size[i] = 512; + xlblk_hardsect_size[i] = 512; + xlblk_max_sectors[i] = 128; + } + xlblk_read_ahead = 8; + + blk_size[xlblk_major] = xlblk_blk_size; + blksize_size[xlblk_major] = xlblk_blksize_size; + hardsect_size[xlblk_major] = xlblk_hardsect_size; + read_ahead[xlblk_major] = xlblk_read_ahead; + max_sectors[xlblk_major] = xlblk_max_sectors; + + blk_init_queue(BLK_DEFAULT_QUEUE(xlblk_major), do_xlblk_request); + + /* + * Turn off barking 'headactive' mode. We dequeue buffer heads as + * soon as we pass them down to Xen. + */ + blk_queue_headactive(BLK_DEFAULT_QUEUE(xlblk_major), 0); + + xlblk_ide_register_disk(0, xen_disk_info.disks[0].capacity); + + printk(KERN_ALERT + "XenoLinux Virtual Block Device Driver installed [device: %d]\n", + xlblk_major); + return 0; + + fail: + return error; +} + +void xlblk_ide_register_disk(int idx, unsigned long capacity) +{ + int units; + int minors; + struct gendisk *gd; + + /* plagarized from ide-probe.c::init_gendisk */ + + units = 2; /* from ide.h::MAX_DRIVES */ + + minors = units * (1<sizes = kmalloc (minors * sizeof(int), GFP_KERNEL); + gd->part = kmalloc (minors * sizeof(struct hd_struct), GFP_KERNEL); + memset(gd->part, 0, minors * sizeof(struct hd_struct)); + + gd->major = xlblk_major; + gd->major_name = XLBLK_MAJOR_NAME; + gd->minor_shift = IDE_PARTN_BITS; + gd->max_p = 1<nr_real = units; + gd->real_devices = NULL; + gd->next = NULL; + gd->fops = &xenolinux_block_fops; + gd->de_arr = kmalloc (sizeof *gd->de_arr * units, GFP_KERNEL); + gd->flags = kmalloc (sizeof *gd->flags * units, GFP_KERNEL); + + if (gd->de_arr) + memset (gd->de_arr, 0, sizeof *gd->de_arr * units); + + if (gd->flags) + memset (gd->flags, 0, sizeof *gd->flags * units); + + add_gendisk(gd); + + xen_disk_info.disks[idx].gendisk = gd; + + /* default disk size is just a big number. in the future, we + need a message to probe the devices to determine the actual size */ + register_disk(gd, MKDEV(xlblk_major, 0), 1<