1991/0925/pc/dma.c (diff list | history)

1991/0803/sys/src/9/pc/dma.c:106,112 – 1991/0925/sys/src/9/pc/dma.c:106,113 (short | long | prev | next)
1991/0803		*/ pa = ((ulong)va) & ~KZERO; if(!isphys(va) || (pa&0xFFFF0000)!=((pa+len)&0xFFFF0000)){ xp->pg = newpage(1, 0, 0);
1991/0925		if(xp->pg == 0) xp->pg = newpage(1, 0, 0);
1991/0803		if(len > BY2PG) len = BY2PG; if(!isread)
1991/0803/sys/src/9/pc/dma.c:115,121 – 1991/0925/sys/src/9/pc/dma.c:116,123
1991/0803		xp->len = len; xp->isread = isread; pa = xp->pg->pa; }
1991/0925		} else xp->len = 0;
1991/0803		/* * this setup must be atomic
1991/0803/sys/src/9/pc/dma.c:161,167 – 1991/0925/sys/src/9/pc/dma.c:163,169
1991/0803		unlock(dp); xp = &dp->x[chan]; if(xp->pg == 0)
1991/0925		if(xp->len == 0)
1991/0803		return; /*
1991/0803/sys/src/9/pc/dma.c:168,173 – 1991/0925/sys/src/9/pc/dma.c:170,174
1991/0803		* copy out of temporary page */ memmove(xp->va, (void*)(KZERO|xp->pg->pa), xp->len); putpage(xp->pg); xp->pg = 0;
1991/0925		xp->len = 0;
1991/0803		}