index : openwrt/upstream	attitude_adjustment barrier_breaker chaos_calmer lede-17.01 less-old-master master old-master openwrt-18.06 openwrt-19.07 upstream
	upstream openwrt	James

aboutsummaryrefslogtreecommitdiffstats

log msg author committer range

path: root/target/linux/ramips/rt288x/base-files/lib

	Commit message (Expand)	Author	Age	Files	Lines
*	ramips: split base-files into subtargets	Adrian Schmutzler	2019-11-03	1	-0/+20

generated by cgit v1.2.3 (git 2.25.1) at 2026-01-29 06:39:05 +0000

/******************************************************************************
 * blkback/vbd.c
 * 
 * Routines for managing virtual block devices (VBDs).
 * 
 * Copyright (c) 2003-2005, Keir Fraser & Steve Hand
 */

#include "common.h"
#include <asm-xen/xenbus.h>

#define vbd_sz(_v)   ((_v)->bdev->bd_part ?				\
	(_v)->bdev->bd_part->nr_sects : (_v)->bdev->bd_disk->capacity)
#define bdev_put(_b) blkdev_put(_b)

unsigned long vbd_size(struct vbd *vbd)
{
	return vbd_sz(vbd);
}

unsigned int vbd_info(struct vbd *vbd)
{
	return vbd->type | (vbd->readonly?VDISK_READONLY:0);
}

unsigned long vbd_secsize(struct vbd *vbd)
{
	return bdev_hardsect_size(vbd->bdev);
}

int vbd_create(blkif_t *blkif, blkif_vdev_t handle, unsigned major,
	       unsigned minor, int readonly)
{
	struct vbd *vbd;

	vbd = &blkif->vbd;
	vbd->handle   = handle; 
	vbd->readonly = readonly;
	vbd->type     = 0;

	vbd->pdevice  = MKDEV(major, minor);

	vbd->bdev = open_by_devnum(
		vbd->pdevice,
		vbd->readonly ? FMODE_READ : FMODE_WRITE);
	if (IS_ERR(vbd->bdev)) {
		DPRINTK("vbd_creat: device %08x doesn't exist.\n",
			vbd->pdevice);
		return -ENOENT;
	}

	if (vbd->bdev->bd_disk == NULL) {
		DPRINTK("vbd_creat: device %08x doesn't exist.\n",
			vbd->pdevice);
		vbd_free(vbd);
		return -ENOENT;
	}

	if (vbd->bdev->bd_disk->flags & GENHD_FL_CD)
		vbd->type |= VDISK_CDROM;
	if (vbd->bdev->bd_disk->flags & GENHD_FL_REMOVABLE)
		vbd->type |= VDISK_REMOVABLE;

	DPRINTK("Successful creation of handle=%04x (dom=%u)\n",
		handle, blkif->domid);
	return 0;
}

void vbd_free(struct vbd *vbd)
{
	if (vbd->bdev)
		bdev_put(vbd->bdev);
	vbd->bdev = NULL;
}

int vbd_translate(struct phys_req *req, blkif_t *blkif, int operation)
{
	struct vbd *vbd = &blkif->vbd;
	int rc = -EACCES;

	if ((operation == WRITE) && vbd->readonly)
		goto out;

	if (unlikely((req->sector_number + req->nr_sects) > vbd_sz(vbd)))
		goto out;

	req->dev  = vbd->pdevice;
	req->bdev = vbd->bdev;
	rc = 0;

 out:
	return rc;
}

/*
 * Local variables:
 *  c-file-style: "linux"
 *  indent-tabs-mode: t
 *  c-indent-level: 8
 *  c-basic-offset: 8
 *  tab-width: 8
 * End:
 */