[deliverable/linux.git] / arch / sparc64 / kernel / iommu_common.c

/* $Id: iommu_common.c,v 1.9 2001/12/17 07:05:09 davem Exp $
 * iommu_common.c: UltraSparc SBUS/PCI common iommu code.
 *
 * Copyright (C) 1999 David S. Miller (davem@redhat.com)
 */

#include "iommu_common.h"

/* You are _strongly_ advised to enable the following debugging code
 * any time you make changes to the sg code below, run it for a while
 * with filesystems mounted read-only before buying the farm... -DaveM
 */

#ifdef VERIFY_SG
static int verify_lengths(struct scatterlist *sglist, int nents, int npages)
{
	int sg_len, dma_len;
	int i, pgcount;
	struct scatterlist *sg;

	sg_len = 0;
	for_each_sg(sglist, sg, nents, i)
		sg_len += sg->length;

	dma_len = 0;
	for_each_sg(sglist, sg, nents, i) {
		if (!sg->dma_length)
			break;
		dma_len += sg->dma_length;
	}

	if (sg_len != dma_len) {
		printk("verify_lengths: Error, different, sg[%d] dma[%d]\n",
		       sg_len, dma_len);
		return -1;
	}

	pgcount = 0;
	for_each_sg(sglist, sg, nents, i) {
		unsigned long start, end;

		if (!sg->dma_length)
			break;

		start = sg->dma_address;
		start = start & IO_PAGE_MASK;

		end = sg->dma_address + sg->dma_length;
		end = (end + (IO_PAGE_SIZE - 1)) & IO_PAGE_MASK;

		pgcount += ((end - start) >> IO_PAGE_SHIFT);
	}

	if (pgcount != npages) {
		printk("verify_lengths: Error, page count wrong, "
		       "npages[%d] pgcount[%d]\n",
		       npages, pgcount);
		return -1;
	}

	/* This test passes... */
	return 0;
}

static int verify_one_map(struct scatterlist *dma_sg, struct scatterlist **__sg, int nents, iopte_t **__iopte)
{
	struct scatterlist *sg = *__sg;
	iopte_t *iopte = *__iopte;
	u32 dlen = dma_sg->dma_length;
	u32 daddr;
	unsigned int sglen;
	unsigned long sgaddr;

	daddr = dma_sg->dma_address;
	sglen = sg->length;
	sgaddr = (unsigned long) sg_virt(sg);
	while (dlen > 0) {
		unsigned long paddr;

		/* SG and DMA_SG must begin at the same sub-page boundary. */
		if ((sgaddr & ~IO_PAGE_MASK) != (daddr & ~IO_PAGE_MASK)) {
			printk("verify_one_map: Wrong start offset "
			       "sg[%08lx] dma[%08x]\n",
			       sgaddr, daddr);
			nents = -1;
			goto out;
		}

		/* Verify the IOPTE points to the right page. */
		paddr = iopte_val(*iopte) & IOPTE_PAGE;
		if ((paddr + PAGE_OFFSET) != (sgaddr & IO_PAGE_MASK)) {
			printk("verify_one_map: IOPTE[%08lx] maps the "
			       "wrong page, should be [%08lx]\n",
			       iopte_val(*iopte), (sgaddr & IO_PAGE_MASK) - PAGE_OFFSET);
			nents = -1;
			goto out;
		}

		/* If this SG crosses a page, adjust to that next page
		 * boundary and loop.
		 */
		if ((sgaddr & IO_PAGE_MASK) ^ ((sgaddr + sglen - 1) & IO_PAGE_MASK)) {
			unsigned long next_page, diff;

			next_page = (sgaddr + IO_PAGE_SIZE) & IO_PAGE_MASK;
			diff = next_page - sgaddr;
			sgaddr += diff;
			daddr += diff;
			sglen -= diff;
			dlen -= diff;
			if (dlen > 0)
				iopte++;
			continue;
		}

		/* SG wholly consumed within this page. */
		daddr += sglen;
		dlen -= sglen;

		if (dlen > 0 && ((daddr & ~IO_PAGE_MASK) == 0))
			iopte++;

		sg = sg_next(sg);
		if (--nents <= 0)
			break;
		sgaddr = (unsigned long) sg_virt(sg);
		sglen = sg->length;
	}
	if (dlen < 0) {
		/* Transfer overrun, big problems. */
		printk("verify_one_map: Transfer overrun by %d bytes.\n",
		       -dlen);
		nents = -1;
	} else {
		/* Advance to next dma_sg implies that the next iopte will
		 * begin it.
		 */
		iopte++;
	}

out:
	*__sg = sg;
	*__iopte = iopte;
	return nents;
}

static int verify_maps(struct scatterlist *sg, int nents, iopte_t *iopte)
{
	struct scatterlist *dma_sg = sg;
	struct scatterlist *orig_dma_sg = dma_sg;
	int orig_nents = nents;

	for (;;) {
		nents = verify_one_map(dma_sg, &sg, nents, &iopte);
		if (nents <= 0)
			break;
		dma_sg = sg_next(dma_sg);
		if (dma_sg->dma_length == 0)
			break;
	}

	if (nents > 0) {
		printk("verify_maps: dma maps consumed by some sgs remain (%d)\n",
		       nents);
		return -1;
	}

	if (nents < 0) {
		printk("verify_maps: Error, messed up mappings, "
		       "at sg %d dma_sg %d\n",
		       (int) (orig_nents + nents), (int) (dma_sg - orig_dma_sg));
		return -1;
	}

	/* This test passes... */
	return 0;
}

void verify_sglist(struct scatterlist *sglist, int nents, iopte_t *iopte, int npages)
{
	struct scatterlist *sg;

	if (verify_lengths(sglist, nents, npages) < 0 ||
	    verify_maps(sglist, nents, iopte) < 0) {
		int i;

		printk("verify_sglist: Crap, messed up mappings, dumping, iodma at ");
		printk("%016lx.\n", sglist->dma_address & IO_PAGE_MASK);

		for_each_sg(sglist, sg, nents, i) {
			printk("sg(%d): page_addr(%p) off(%x) length(%x) "
			       "dma_address[%016x] dma_length[%016x]\n",
			       i,
			       page_address(sg_page(sg)), sg->offset,
			       sg->length,
			       sg->dma_address, sg->dma_length);
		}
	}

	/* Seems to be ok */
}
#endif

unsigned long prepare_sg(struct scatterlist *sg, int nents)
{
	struct scatterlist *dma_sg = sg;
	unsigned long prev;
	u32 dent_addr, dent_len;

	prev  = (unsigned long) sg_virt(sg);
	prev += (unsigned long) (dent_len = sg->length);
	dent_addr = (u32) ((unsigned long)(sg_virt(sg)) & (IO_PAGE_SIZE - 1UL));
	while (--nents) {
		unsigned long addr;

		sg = sg_next(sg);
		addr = (unsigned long) sg_virt(sg);
		if (! VCONTIG(prev, addr)) {
			dma_sg->dma_address = dent_addr;
			dma_sg->dma_length = dent_len;
			dma_sg = sg_next(dma_sg);

			dent_addr = ((dent_addr +
				      dent_len +
				      (IO_PAGE_SIZE - 1UL)) >> IO_PAGE_SHIFT);
			dent_addr <<= IO_PAGE_SHIFT;
			dent_addr += addr & (IO_PAGE_SIZE - 1UL);
			dent_len = 0;
		}
		dent_len += sg->length;
		prev = addr + sg->length;
	}
	dma_sg->dma_address = dent_addr;
	dma_sg->dma_length = dent_len;

	if (dma_sg != sg) {
		dma_sg = next_sg(dma_sg);
		dma_sg->dma_length = 0;
	}

	return ((unsigned long) dent_addr +
		(unsigned long) dent_len +
		(IO_PAGE_SIZE - 1UL)) >> IO_PAGE_SHIFT;
}
Commit	Line	Data
1da177e4 LT	1	/* $Id: iommu_common.c,v 1.9 2001/12/17 07:05:09 davem Exp $
	2	* iommu_common.c: UltraSparc SBUS/PCI common iommu code.
	3	*
	4	* Copyright (C) 1999 David S. Miller (davem@redhat.com)
	5	*/
	6
	7	#include "iommu_common.h"
	8
	9	/* You are _strongly_ advised to enable the following debugging code
	10	* any time you make changes to the sg code below, run it for a while
	11	* with filesystems mounted read-only before buying the farm... -DaveM
	12	*/
	13
	14	#ifdef VERIFY_SG
24c31eed	15	static int verify_lengths(struct scatterlist *sglist, int nents, int npages)
1da177e4 LT	16	{
	17	int sg_len, dma_len;
	18	int i, pgcount;
24c31eed	19	struct scatterlist *sg;
1da177e4 LT	20
1da177e4 LT	21	sg_len = 0;
24c31eed FT	22	for_each_sg(sglist, sg, nents, i)
24c31eed FT	23	sg_len += sg->length;
1da177e4 LT	24
1da177e4 LT	25	dma_len = 0;
24c31eed FT	26	for_each_sg(sglist, sg, nents, i) {
	27	if (!sg->dma_length)
	28	break;
	29	dma_len += sg->dma_length;
	30	}
1da177e4 LT	31
	32	if (sg_len != dma_len) {
	33	printk("verify_lengths: Error, different, sg[%d] dma[%d]\n",
	34	sg_len, dma_len);
	35	return -1;
	36	}
	37
	38	pgcount = 0;
24c31eed	39	for_each_sg(sglist, sg, nents, i) {
1da177e4 LT	40	unsigned long start, end;
1da177e4 LT	41
24c31eed FT	42	if (!sg->dma_length)
	43	break;
	44
	45	start = sg->dma_address;
1da177e4 LT	46	start = start & IO_PAGE_MASK;
1da177e4 LT	47
24c31eed	48	end = sg->dma_address + sg->dma_length;
1da177e4 LT	49	end = (end + (IO_PAGE_SIZE - 1)) & IO_PAGE_MASK;
	50
	51	pgcount += ((end - start) >> IO_PAGE_SHIFT);
	52	}
	53
	54	if (pgcount != npages) {
	55	printk("verify_lengths: Error, page count wrong, "
	56	"npages[%d] pgcount[%d]\n",
	57	npages, pgcount);
	58	return -1;
	59	}
	60
	61	/* This test passes... */
	62	return 0;
	63	}
	64
	65	static int verify_one_map(struct scatterlist dma_sg, struct scatterlist __sg, int nents, iopte_t *__iopte)
	66	{
	67	struct scatterlist sg = __sg;
	68	iopte_t iopte = __iopte;
	69	u32 dlen = dma_sg->dma_length;
	70	u32 daddr;
	71	unsigned int sglen;
	72	unsigned long sgaddr;
	73
	74	daddr = dma_sg->dma_address;
	75	sglen = sg->length;
58b053e4	76	sgaddr = (unsigned long) sg_virt(sg);
1da177e4 LT	77	while (dlen > 0) {
	78	unsigned long paddr;
	79
	80	/* SG and DMA_SG must begin at the same sub-page boundary. */
	81	if ((sgaddr & ~IO_PAGE_MASK) != (daddr & ~IO_PAGE_MASK)) {
	82	printk("verify_one_map: Wrong start offset "
	83	"sg[%08lx] dma[%08x]\n",
	84	sgaddr, daddr);
	85	nents = -1;
	86	goto out;
	87	}
	88
	89	/* Verify the IOPTE points to the right page. */
	90	paddr = iopte_val(*iopte) & IOPTE_PAGE;
	91	if ((paddr + PAGE_OFFSET) != (sgaddr & IO_PAGE_MASK)) {
	92	printk("verify_one_map: IOPTE[%08lx] maps the "
	93	"wrong page, should be [%08lx]\n",
	94	iopte_val(*iopte), (sgaddr & IO_PAGE_MASK) - PAGE_OFFSET);
	95	nents = -1;
	96	goto out;
	97	}
	98
	99	/* If this SG crosses a page, adjust to that next page
	100	* boundary and loop.
	101	*/
	102	if ((sgaddr & IO_PAGE_MASK) ^ ((sgaddr + sglen - 1) & IO_PAGE_MASK)) {
	103	unsigned long next_page, diff;
	104
	105	next_page = (sgaddr + IO_PAGE_SIZE) & IO_PAGE_MASK;
	106	diff = next_page - sgaddr;
	107	sgaddr += diff;
	108	daddr += diff;
	109	sglen -= diff;
	110	dlen -= diff;
	111	if (dlen > 0)
	112	iopte++;
	113	continue;
	114	}
	115
	116	/* SG wholly consumed within this page. */
	117	daddr += sglen;
	118	dlen -= sglen;
	119
	120	if (dlen > 0 && ((daddr & ~IO_PAGE_MASK) == 0))
	121	iopte++;
	122
24c31eed	123	sg = sg_next(sg);
1da177e4 LT	124	if (--nents <= 0)
1da177e4 LT	125	break;
58b053e4	126	sgaddr = (unsigned long) sg_virt(sg);
1da177e4 LT	127	sglen = sg->length;
	128	}
	129	if (dlen < 0) {
	130	/* Transfer overrun, big problems. */
	131	printk("verify_one_map: Transfer overrun by %d bytes.\n",
	132	-dlen);
	133	nents = -1;
	134	} else {
	135	/* Advance to next dma_sg implies that the next iopte will
	136	* begin it.
	137	*/
	138	iopte++;
	139	}
	140
	141	out:
	142	*__sg = sg;
	143	*__iopte = iopte;
	144	return nents;
	145	}
	146
	147	static int verify_maps(struct scatterlist sg, int nents, iopte_t iopte)
	148	{
	149	struct scatterlist *dma_sg = sg;
	150	struct scatterlist *orig_dma_sg = dma_sg;
	151	int orig_nents = nents;
	152
	153	for (;;) {
	154	nents = verify_one_map(dma_sg, &sg, nents, &iopte);
	155	if (nents <= 0)
	156	break;
24c31eed	157	dma_sg = sg_next(dma_sg);
1da177e4 LT	158	if (dma_sg->dma_length == 0)
	159	break;
	160	}
	161
	162	if (nents > 0) {
	163	printk("verify_maps: dma maps consumed by some sgs remain (%d)\n",
	164	nents);
	165	return -1;
	166	}
	167
	168	if (nents < 0) {
	169	printk("verify_maps: Error, messed up mappings, "
	170	"at sg %d dma_sg %d\n",
	171	(int) (orig_nents + nents), (int) (dma_sg - orig_dma_sg));
	172	return -1;
	173	}
	174
	175	/* This test passes... */
	176	return 0;
	177	}
	178
24c31eed	179	void verify_sglist(struct scatterlist sglist, int nents, iopte_t iopte, int npages)
1da177e4	180	{
24c31eed FT	181	struct scatterlist *sg;
	182
	183	if (verify_lengths(sglist, nents, npages) < 0 \|\|
	184	verify_maps(sglist, nents, iopte) < 0) {
1da177e4 LT	185	int i;
	186
	187	printk("verify_sglist: Crap, messed up mappings, dumping, iodma at ");
24c31eed	188	printk("%016lx.\n", sglist->dma_address & IO_PAGE_MASK);
1da177e4	189
24c31eed	190	for_each_sg(sglist, sg, nents, i) {
1da177e4	191	printk("sg(%d): page_addr(%p) off(%x) length(%x) "
24c31eed	192	"dma_address[%016x] dma_length[%016x]\n",
1da177e4	193	i,
58b053e4	194	page_address(sg_page(sg)), sg->offset,
24c31eed FT	195	sg->length,
24c31eed FT	196	sg->dma_address, sg->dma_length);
1da177e4 LT	197	}
	198	}
	199
	200	/* Seems to be ok */
	201	}
	202	#endif
	203
	204	unsigned long prepare_sg(struct scatterlist *sg, int nents)
	205	{
	206	struct scatterlist *dma_sg = sg;
	207	unsigned long prev;
	208	u32 dent_addr, dent_len;
	209
58b053e4	210	prev = (unsigned long) sg_virt(sg);
1da177e4	211	prev += (unsigned long) (dent_len = sg->length);
58b053e4	212	dent_addr = (u32) ((unsigned long)(sg_virt(sg)) & (IO_PAGE_SIZE - 1UL));
1da177e4 LT	213	while (--nents) {
	214	unsigned long addr;
	215
24c31eed	216	sg = sg_next(sg);
58b053e4	217	addr = (unsigned long) sg_virt(sg);
1da177e4 LT	218	if (! VCONTIG(prev, addr)) {
	219	dma_sg->dma_address = dent_addr;
	220	dma_sg->dma_length = dent_len;
24c31eed	221	dma_sg = sg_next(dma_sg);
1da177e4 LT	222
	223	dent_addr = ((dent_addr +
	224	dent_len +
	225	(IO_PAGE_SIZE - 1UL)) >> IO_PAGE_SHIFT);
	226	dent_addr <<= IO_PAGE_SHIFT;
	227	dent_addr += addr & (IO_PAGE_SIZE - 1UL);
	228	dent_len = 0;
	229	}
	230	dent_len += sg->length;
	231	prev = addr + sg->length;
	232	}
	233	dma_sg->dma_address = dent_addr;
	234	dma_sg->dma_length = dent_len;
	235
cb92ae81 FT	236	if (dma_sg != sg) {
	237	dma_sg = next_sg(dma_sg);
	238	dma_sg->dma_length = 0;
	239	}
	240
1da177e4 LT	241	return ((unsigned long) dent_addr +
	242	(unsigned long) dent_len +
	243	(IO_PAGE_SIZE - 1UL)) >> IO_PAGE_SHIFT;
	244	}