#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;	uint	bytes;} ialloc; static Block*_allocb(int size){	Block *b;	uchar *p;	int n; 	n = BLOCKALIGN + ROUNDUP(size+Hdrspc, BLOCKALIGN) + sizeof(Block);	if((p = mallocz(n, 0)) == nil)		return nil; 	b = (Block*)(p + n - sizeof(Block));	/* block at end of allocated space */	b->base = p;	b->next = nil;	b->list = nil;	b->free = 0;	b->flag = 0; 	/* align base and bounds of data */	b->lim = (uchar*)(PTR2UINT(b) & ~(BLOCKALIGN-1)); 	/* align start of writable data, leaving space below for added headers */	b->rp = b->lim - ROUNDUP(size, BLOCKALIGN);	b->wp = b->rp; 	if(b->rp < b->base || b->lim - b->rp < size)		panic("_allocb"); 	return b;} Block*allocb(int size){	Block *b; 	/*	 * Check in a process and wait until successful.	 * Can still error out of here, though.	 */	if(up == nil)		panic("allocb without up: %#p", getcallerpc(&size));	if((b = _allocb(size)) == nil){		xsummary();		mallocsummary();		panic("allocb: no memory for %d bytes", size);	}	setmalloctag(b, getcallerpc(&size)); 	return b;} Block*iallocb(int size){	Block *b;	static int m1, m2, mp; 	if(ialloc.bytes > conf.ialloc){		if((m1++%10000)==0){			if(mp++ > 1000){				active.exiting = 1;				exit(0);			}			iprint("iallocb: limited %ud/%ud\n",				ialloc.bytes, conf.ialloc);		}		return nil;	} 	if((b = _allocb(size)) == nil){		if((m2++%10000)==0){			if(mp++ > 1000){				active.exiting = 1;				exit(0);			}			iprint("iallocb: no memory %ud/%ud\n",				ialloc.bytes, conf.ialloc);		}		return nil;	}	setmalloctag(b, getcallerpc(&size));	b->flag = BINTR; 	ilock(&ialloc);	ialloc.bytes += b->lim - b->base;	iunlock(&ialloc); 	return b;} voidfreeb(Block *b){	void *dead = (void*)Bdead;	uchar *p; 	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) {		b->free(b);		return;	}	if(b->flag & BINTR) {		ilock(&ialloc);		ialloc.bytes -= b->lim - b->base;		iunlock(&ialloc);	} 	p = b->base; 	/* 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; 	free(p);} voidcheckb(Block *b, char *msg){	void *dead = (void*)Bdead; 	if(b == dead)		panic("checkb b %s %#p", msg, b);	if(b->base == dead || b->lim == dead || b->next == dead	  || b->rp == dead || b->wp == dead){		print("checkb: base %#p lim %#p next %#p\n",			b->base, b->lim, b->next);		print("checkb: rp %#p wp %#p\n", b->rp, b->wp);		panic("checkb dead: %s", msg);	} 	if(b->base > b->lim)		panic("checkb 0 %s %#p %#p", msg, b->base, b->lim);	if(b->rp < b->base)		panic("checkb 1 %s %#p %#p", msg, b->base, b->rp);	if(b->wp < b->base)		panic("checkb 2 %s %#p %#p", msg, b->base, b->wp);	if(b->rp > b->lim)		panic("checkb 3 %s %#p %#p", msg, b->rp, b->lim);	if(b->wp > b->lim)		panic("checkb 4 %s %#p %#p", msg, b->wp, b->lim);} voidiallocsummary(void){	print("ialloc %ud/%ud\n", ialloc.bytes, conf.ialloc);}