/* * allocate Blocks from uncached memory */#include	"u.h"#include	"../port/lib.h"#include	"mem.h"#include	"dat.h"#include	"fns.h"#include	"error.h" enum{	Hdrspc		= 64,		/* leave room for high-level headers */	Bdead		= 0x51494F42,	/* "QIOB" */}; struct{	Lock;	ulong	bytes;} ucialloc; static Block*_ucallocb(int size){	Block *b;	uintptr addr; 	if((b = ucalloc(sizeof(Block)+size+Hdrspc)) == nil)		return nil; 	b->next = nil;	b->list = nil;	b->free = nil;	b->flag = 0; 	/* align start of data portion by rounding up */	addr = (uintptr)b;	addr = ROUND(addr + sizeof(Block), BLOCKALIGN);	b->base = (uchar*)addr; 	/* align end of data portion by rounding down */	b->lim = (uchar*)b + msize(b);	addr = (uintptr)b->lim;	addr &= ~(BLOCKALIGN-1);	b->lim = (uchar*)addr; 	/* leave sluff at beginning for added headers */	b->rp = b->lim - ROUND(size, BLOCKALIGN);	if(b->rp < b->base)		panic("_ucallocb");	b->wp = b->rp; 	return b;} Block*ucallocb(int size){	Block *b; 	/*	 * Check in a process and wait until successful.	 * Can still error out of here, though.	 */	if(up == nil)		panic("ucallocb without up: %#p", getcallerpc(&size));	if((b = _ucallocb(size)) == nil)		panic("ucallocb: no memory for %d bytes", size);	setmalloctag(b, getcallerpc(&size)); 	return b;} Block*uciallocb(int size){	Block *b;	static int m1, m2, mp; 	if((b = _ucallocb(size)) == nil){		if(0 && (m2++%10000)==0){			if(mp++ > 1000)				panic("uciallocb: out of memory");			iprint("uciallocb: no memory %lud/%lud\n",				ucialloc.bytes, conf.ialloc);		}		return nil;	}	setmalloctag(b, getcallerpc(&size));	b->flag = BINTR; 	ilock(&ucialloc);	ucialloc.bytes += b->lim - b->base;	iunlock(&ucialloc); 	return b;} voiducfreeb(Block *b){	void *dead = (void*)Bdead; 	if(b == nil)		return; 	/*	 * drivers which perform non cache coherent DMA manage their own buffer	 * pool of uncached buffers and provide their own free routine.	 */	if(b->free != nil) {		b->free(b);		return;	}	if(b->flag & BINTR) {		ilock(&ucialloc);		ucialloc.bytes -= b->lim - b->base;		iunlock(&ucialloc);	} 	/* poison the block in case someone is still holding onto it */	b->next = dead;	b->rp = dead;	b->wp = dead;	b->lim = dead;	b->base = dead; 	ucfree(b);}