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Diffstat (limited to 'xenolinux-2.4.24-sparse/arch/xeno/drivers/block/xl_vbd.c')
-rw-r--r--xenolinux-2.4.24-sparse/arch/xeno/drivers/block/xl_vbd.c343
1 files changed, 343 insertions, 0 deletions
diff --git a/xenolinux-2.4.24-sparse/arch/xeno/drivers/block/xl_vbd.c b/xenolinux-2.4.24-sparse/arch/xeno/drivers/block/xl_vbd.c
new file mode 100644
index 0000000000..d4e01f73d8
--- /dev/null
+++ b/xenolinux-2.4.24-sparse/arch/xeno/drivers/block/xl_vbd.c
@@ -0,0 +1,343 @@
+/******************************************************************************
+ * xl_vbd.c
+ *
+ * Xenolinux virtual block-device driver (xvd).
+ *
+ */
+
+#include "xl_block.h"
+#include <linux/blk.h>
+
+/*
+ * For convenience we distinguish between ide, scsi and 'other' (i.e.
+ * potentially combinations of the two) in the naming scheme and in a few
+ * other places (like default readahead, etc).
+ */
+#define XLIDE_MAJOR_NAME "hd"
+#define XLSCSI_MAJOR_NAME "sd"
+#define XLVBD_MAJOR_NAME "xvd"
+
+#define XLIDE_DEVS_PER_MAJOR 2
+#define XLSCSI_DEVS_PER_MAJOR 16
+#define XLVBD_DEVS_PER_MAJOR 16
+
+#define XLIDE_PARTN_SHIFT 6 /* amount to shift minor to get 'real' minor */
+#define XLIDE_MAX_PART (1 << XLIDE_PARTN_SHIFT) /* minors per ide vbd */
+
+#define XLSCSI_PARTN_SHIFT 4 /* amount to shift minor to get 'real' minor */
+#define XLSCSI_MAX_PART (1 << XLSCSI_PARTN_SHIFT) /* minors per scsi vbd */
+
+#define XLVBD_PARTN_SHIFT 6 /* amount to shift minor to get 'real' minor */
+#define XLVBD_MAX_PART (1 << XLVBD_PARTN_SHIFT) /* minors per 'other' vbd */
+
+/* The below are for the generic drivers/block/ll_rw_block.c code. */
+static int xlide_blksize_size[256];
+static int xlide_hardsect_size[256];
+static int xlide_max_sectors[256];
+static int xlscsi_blksize_size[256];
+static int xlscsi_hardsect_size[256];
+static int xlscsi_max_sectors[256];
+static int xlvbd_blksize_size[256];
+static int xlvbd_hardsect_size[256];
+static int xlvbd_max_sectors[256];
+
+static struct block_device_operations xlvbd_block_fops =
+{
+ open: xenolinux_block_open,
+ release: xenolinux_block_release,
+ ioctl: xenolinux_block_ioctl,
+ check_media_change: xenolinux_block_check,
+ revalidate: xenolinux_block_revalidate,
+};
+
+/*
+ * Set up all the linux device goop for the virtual block devices (vbd's) that
+ * xen tells us about. Note that although from xen's pov VBDs are addressed
+ * simply an opaque 16-bit device number, the domain creation tools
+ * conventionally allocate these numbers to correspond to those used by 'real'
+ * linux -- this is just for convenience as it means e.g. that the same
+ * /etc/fstab can be used when booting with or without xen.
+ */
+int __init xlvbd_init(xen_disk_info_t *xdi)
+{
+ int i, j, result, max_part;
+ struct gendisk *gd = NULL;
+ kdev_t device;
+ unsigned short major, minor, partno;
+ int is_ide, is_scsi;
+ char *major_name;
+ unsigned char buf[64];
+
+ SET_MODULE_OWNER(&xlvbd_block_fops);
+
+ /* Initialize the global arrays. */
+ for ( i = 0; i < 256; i++ )
+ {
+ /* from the generic ide code (drivers/ide/ide-probe.c, etc) */
+ xlide_blksize_size[i] = 1024;
+ xlide_hardsect_size[i] = 512;
+ xlide_max_sectors[i] = 128; /* 'hwif->rqsize' if we knew it */
+
+ /* from the generic scsi disk code (drivers/scsi/sd.c) */
+ xlscsi_blksize_size[i] = 1024; /* XXX 512; */
+ xlscsi_hardsect_size[i] = 512;
+ xlscsi_max_sectors[i] = 128*8; /* XXX 128; */
+
+ /* we don't really know what to set these too since it depends */
+ xlvbd_blksize_size[i] = 512;
+ xlvbd_hardsect_size[i] = 512;
+ xlvbd_max_sectors[i] = 128;
+ }
+
+ /*
+ * We need to loop through each major device we've been told about and:
+ * a) register the appropriate blkdev
+ * b) setup the indexed-by-major global arrays (blk_size[],
+ * blksize_size[], hardsect_size[], max_sectors[], read_ahead[])
+ * c) setup the block queue + make it sensible
+ * d) create an appropriate gendisk structure, and
+ * e) register the gendisk
+ */
+ for ( i = 0; i < xdi->count; i++ )
+ {
+ device = xdi->disks[i].device;
+ major = MAJOR(device);
+ minor = MINOR(device);
+ is_ide = IDE_DISK_MAJOR(major); /* is this an ide device? */
+ is_scsi= SCSI_BLK_MAJOR(major); /* is this a scsi device? */
+
+ if ( is_ide )
+ {
+ major_name = XLIDE_MAJOR_NAME;
+ max_part = XLIDE_MAX_PART;
+ }
+ else if ( is_scsi )
+ {
+ major_name = XLSCSI_MAJOR_NAME;
+ max_part = XLSCSI_MAX_PART;
+ }
+ else
+ {
+ major_name = XLVBD_MAJOR_NAME;
+ max_part = XLVBD_MAX_PART;
+ }
+
+ partno = minor & (max_part - 1);
+
+ if ( (gd = get_gendisk(device)) == NULL )
+ {
+ result = register_blkdev(major, major_name, &xlvbd_block_fops);
+ if ( result < 0 )
+ {
+ printk(KERN_ALERT "XL VBD: can't get major %d\n", major);
+ continue;
+ }
+
+ if ( is_ide )
+ {
+ blksize_size[major] = xlide_blksize_size;
+ hardsect_size[major] = xlide_hardsect_size;
+ max_sectors[major] = xlide_max_sectors;
+ read_ahead[major] = 8; /* from drivers/ide/ide-probe.c */
+ }
+ else if ( is_scsi )
+ {
+ blksize_size[major] = xlscsi_blksize_size;
+ hardsect_size[major] = xlscsi_hardsect_size;
+ max_sectors[major] = xlscsi_max_sectors;
+ read_ahead[major] = 0; /* XXX 8; -- guessing */
+ }
+ else
+ {
+ blksize_size[major] = xlvbd_blksize_size;
+ hardsect_size[major] = xlvbd_hardsect_size;
+ max_sectors[major] = xlvbd_max_sectors;
+ read_ahead[major] = 8;
+ }
+
+ blk_init_queue(BLK_DEFAULT_QUEUE(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(major), 0);
+
+ /* Construct an appropriate gendisk structure. */
+ gd = kmalloc(sizeof(struct gendisk), GFP_KERNEL);
+ gd->major = major;
+ gd->major_name = major_name;
+
+ gd->max_p = max_part;
+ if ( is_ide )
+ {
+ gd->minor_shift = XLIDE_PARTN_SHIFT;
+ gd->nr_real = XLIDE_DEVS_PER_MAJOR;
+ }
+ else if ( is_scsi )
+ {
+ gd->minor_shift = XLSCSI_PARTN_SHIFT;
+ gd->nr_real = XLSCSI_DEVS_PER_MAJOR;
+ }
+ else
+ {
+ gd->minor_shift = XLVBD_PARTN_SHIFT;
+ gd->nr_real = XLVBD_DEVS_PER_MAJOR;
+ }
+
+ /*
+ ** The sizes[] and part[] arrays hold the sizes and other
+ ** information about every partition with this 'major' (i.e.
+ ** every disk sharing the 8 bit prefix * max partns per disk)
+ */
+ gd->sizes = kmalloc(max_part*gd->nr_real*sizeof(int), GFP_KERNEL);
+ gd->part = kmalloc(max_part*gd->nr_real*sizeof(struct hd_struct),
+ GFP_KERNEL);
+ memset(gd->sizes, 0, max_part * gd->nr_real * sizeof(int));
+ memset(gd->part, 0, max_part * gd->nr_real
+ * sizeof(struct hd_struct));
+
+
+ gd->real_devices = kmalloc(gd->nr_real * sizeof(xl_disk_t),
+ GFP_KERNEL);
+ memset(gd->real_devices, 0, gd->nr_real * sizeof(xl_disk_t));
+
+ gd->next = NULL;
+ gd->fops = &xlvbd_block_fops;
+
+ gd->de_arr = kmalloc(gd->nr_real * sizeof(*gd->de_arr),
+ GFP_KERNEL);
+ gd->flags = kmalloc(gd->nr_real * sizeof(*gd->flags), GFP_KERNEL);
+
+ memset(gd->de_arr, 0, gd->nr_real * sizeof(*gd->de_arr));
+ memset(gd->flags, 0, gd->nr_real * sizeof(*gd->flags));
+
+ add_gendisk(gd);
+
+ blk_size[major] = gd->sizes;
+ }
+
+ if ( XD_READONLY(xdi->disks[i].info) )
+ set_device_ro(device, 1);
+
+ gd->flags[minor >> gd->minor_shift] |= GENHD_FL_XENO;
+
+ if ( partno != 0 )
+ {
+ /*
+ * If this was previously set up as a real disc we will have set
+ * up partition-table information. Virtual partitions override
+ * 'real' partitions, and the two cannot coexist on a device.
+ */
+ if ( gd->sizes[minor & ~(max_part-1)] != 0 )
+ {
+ kdev_t dev = device & ~(max_part-1);
+ for ( j = max_part - 1; j >= 0; j-- )
+ {
+ invalidate_device(dev+j, 1);
+ gd->part[MINOR(dev+j)].start_sect = 0;
+ gd->part[MINOR(dev+j)].nr_sects = 0;
+ gd->sizes[MINOR(dev+j)] = 0;
+ }
+ printk(KERN_ALERT
+ "Virtual partitions found for /dev/%s - ignoring any "
+ "real partition information we may have found.\n",
+ disk_name(gd, MINOR(device), buf));
+ }
+
+ /* Need to skankily setup 'partition' information */
+ gd->part[minor].start_sect = 0;
+ gd->part[minor].nr_sects = xdi->disks[i].capacity;
+ gd->sizes[minor] = xdi->disks[i].capacity;
+
+ gd->flags[minor >> gd->minor_shift] |= GENHD_FL_VIRT_PARTNS;
+ }
+ else
+ {
+ /* Some final fix-ups depending on the device type */
+ switch ( XD_TYPE(xdi->disks[i].info) )
+ {
+ case XD_TYPE_CDROM:
+ case XD_TYPE_FLOPPY:
+ case XD_TYPE_TAPE:
+ gd->part[minor].nr_sects = xdi->disks[i].capacity;
+ gd->sizes[minor] = xdi->disks[i].capacity>>(BLOCK_SIZE_BITS-9);
+ gd->flags[minor >> gd->minor_shift] |= GENHD_FL_REMOVABLE;
+ printk(KERN_ALERT
+ "Skipping partition check on %s /dev/%s\n",
+ XD_TYPE(xdi->disks[i].info)==XD_TYPE_CDROM ? "cdrom" :
+ (XD_TYPE(xdi->disks[i].info)==XD_TYPE_TAPE ? "tape" :
+ "floppy"), disk_name(gd, MINOR(device), buf));
+ break;
+
+ case XD_TYPE_DISK:
+ /* Only check partitions on real discs (not virtual!). */
+ if ( gd->flags[minor>>gd->minor_shift] & GENHD_FL_VIRT_PARTNS )
+ {
+ printk(KERN_ALERT
+ "Skipping partition check on virtual /dev/%s\n",
+ disk_name(gd, MINOR(device), buf));
+ break;
+ }
+ register_disk(gd, device, gd->max_p, &xlvbd_block_fops,
+ xdi->disks[i].capacity);
+ break;
+
+ default:
+ printk(KERN_ALERT "XenoLinux: unknown device type %d\n",
+ XD_TYPE(xdi->disks[i].info));
+ break;
+ }
+ }
+
+ printk(KERN_ALERT "XenoLinux Virtual Block Device Driver "
+ "installed [device: %04x]\n", device);
+ }
+
+ return 0;
+}
+
+void xlvbd_cleanup(void)
+{
+ int is_ide, is_scsi, i;
+ struct gendisk *gd;
+ char *major_name;
+ int major;
+
+ for ( major = 0; major < MAX_BLKDEV; major++ )
+ {
+ if ( (gd = get_gendisk(MKDEV(major, 0))) == NULL )
+ continue;
+
+ /*
+ * If this is a 'Xeno' blkdev then at least one unit will have the Xeno
+ * flag set.
+ */
+ for ( i = 0; i < gd->nr_real; i++ )
+ if ( gd->flags[i] & GENHD_FL_XENO )
+ break;
+ if ( i == gd->nr_real )
+ continue;
+
+ is_ide = IDE_DISK_MAJOR(major); /* is this an ide device? */
+ is_scsi = SCSI_BLK_MAJOR(major); /* is this a scsi device? */
+
+ blk_cleanup_queue(BLK_DEFAULT_QUEUE(major));
+
+ if ( is_ide )
+ major_name = XLIDE_MAJOR_NAME;
+ else if ( is_scsi )
+ major_name = XLSCSI_MAJOR_NAME;
+ else
+ major_name = XLVBD_MAJOR_NAME;
+
+ if ( unregister_blkdev(major, major_name) != 0 )
+ printk(KERN_ALERT "XenoLinux Virtual Block Device Driver:"
+ "major device %04x uninstalled w/ errors\n", major);
+ }
+}
+
+#ifdef MODULE
+module_init(xlvbd_init);
+module_exit(xlvbd_cleanup);
+#endif
generated by cgit v1.2.3 (git 2.25.1) at 2024-05-20 19:37:19 +0000