Commit a98f5654 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Konrad Rzeszutek Wilk
Browse files

xen-swiotlb: split xen_swiotlb_init 



Split xen_swiotlb_init into a normal an an early case.  That makes both
much simpler and more readable, and also allows marking the early
code as __init and x86-only.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
parent 5d0538b2

arch/arm/xen/mm.c

+1 −1
Original line number Diff line number Diff line
@@ -140,7 +140,7 @@ static int __init xen_mm_init(void) 
	struct gnttab_cache_flush cflush;

	if (!xen_initial_domain())

		return 0;

	xen_swiotlb_init(1, false);

	xen_swiotlb_init();



	cflush.op = 0;

	cflush.a.dev_bus_addr = 0;

arch/x86/xen/pci-swiotlb-xen.c

+2 −2
Original line number Diff line number Diff line
@@ -59,7 +59,7 @@ int __init pci_xen_swiotlb_detect(void) 
void __init pci_xen_swiotlb_init(void)

{

	if (xen_swiotlb) {

		xen_swiotlb_init(1, true /* early */);

		xen_swiotlb_init_early();

		dma_ops = &xen_swiotlb_dma_ops;



#ifdef CONFIG_PCI
@@ -76,7 +76,7 @@ int pci_xen_swiotlb_init_late(void) 
	if (xen_swiotlb)

		return 0;



	rc = xen_swiotlb_init(1, false /* late */);

	rc = xen_swiotlb_init();

	if (rc)

		return rc;

drivers/xen/swiotlb-xen.c

+70 −54
Original line number Diff line number Diff line
@@ -156,32 +156,25 @@ static const char *xen_swiotlb_error(enum xen_swiotlb_err err) 


#define DEFAULT_NSLABS		ALIGN(SZ_64M >> IO_TLB_SHIFT, IO_TLB_SEGSIZE)



int __ref xen_swiotlb_init(int verbose, bool early)

int __ref xen_swiotlb_init(void)

{

	unsigned long bytes, order;

	int rc = -ENOMEM;

	enum xen_swiotlb_err m_ret = XEN_SWIOTLB_UNKNOWN;

	unsigned long nslabs, bytes, order;

	unsigned int repeat = 3;

	int rc = -ENOMEM;

	char *start;

	unsigned long nslabs;



	nslabs = swiotlb_nr_tbl();

retry:

	if (!nslabs)

		nslabs = DEFAULT_NSLABS;

retry:

	m_ret = XEN_SWIOTLB_ENOMEM;

	bytes = nslabs << IO_TLB_SHIFT;

	order = get_order(bytes);



	/*

	 * Get IO TLB memory from any location.

	 */

	if (early) {

		start = memblock_alloc(PAGE_ALIGN(bytes),

						  PAGE_SIZE);

		if (!start)

			panic("%s: Failed to allocate %lu bytes align=0x%lx\n",

			      __func__, PAGE_ALIGN(bytes), PAGE_SIZE);

	} else {

#define SLABS_PER_PAGE (1 << (PAGE_SHIFT - IO_TLB_SHIFT))

#define IO_TLB_MIN_SLABS ((1<<20) >> IO_TLB_SHIFT)

	while ((SLABS_PER_PAGE << order) > IO_TLB_MIN_SLABS) {
@@ -190,62 +183,85 @@ int __ref xen_swiotlb_init(int verbose, bool early) 
			break;

		order--;

	}

	if (!start)

		goto error;

	if (order != get_order(bytes)) {

		pr_warn("Warning: only able to allocate %ld MB for software IO TLB\n",

			(PAGE_SIZE << order) >> 20);

		nslabs = SLABS_PER_PAGE << order;

		bytes = nslabs << IO_TLB_SHIFT;

	}

	}

	if (!start) {

		m_ret = XEN_SWIOTLB_ENOMEM;

		goto error;

	}



	/*

	 * And replace that memory with pages under 4GB.

	 */

	rc = xen_swiotlb_fixup(start,

			       bytes,

			       nslabs);

	rc = xen_swiotlb_fixup(start, bytes, nslabs);

	if (rc) {

		if (early)

			memblock_free(__pa(start),

				      PAGE_ALIGN(bytes));

		else {

		free_pages((unsigned long)start, order);

			start = NULL;

		}

		m_ret = XEN_SWIOTLB_EFIXUP;

		goto error;

	}

	if (early) {

		if (swiotlb_init_with_tbl(start, nslabs,

			 verbose))

			panic("Cannot allocate SWIOTLB buffer");

		rc = 0;

	} else

	rc = swiotlb_late_init_with_tbl(start, nslabs);



	if (!rc)

		swiotlb_set_max_segment(PAGE_SIZE);



	if (rc)

		return rc;

	swiotlb_set_max_segment(PAGE_SIZE);

	return 0;

error:

	if (repeat--) {

		nslabs = max(1024UL, /* Min is 2MB */

					(nslabs >> 1));

		/* Min is 2MB */

		nslabs = max(1024UL, (nslabs >> 1));

		pr_info("Lowering to %luMB\n",

			(nslabs << IO_TLB_SHIFT) >> 20);

		goto retry;

	}

	pr_err("%s (rc:%d)\n", xen_swiotlb_error(m_ret), rc);

	if (early)

		panic("%s (rc:%d)", xen_swiotlb_error(m_ret), rc);

	else

	free_pages((unsigned long)start, order);

	return rc;

}



#ifdef CONFIG_X86

void __init xen_swiotlb_init_early(void)

{

	unsigned long nslabs, bytes;

	unsigned int repeat = 3;

	char *start;

	int rc;



	nslabs = swiotlb_nr_tbl();

	if (!nslabs)

		nslabs = DEFAULT_NSLABS;

retry:

	/*

	 * Get IO TLB memory from any location.

	 */

	bytes = nslabs << IO_TLB_SHIFT;

	start = memblock_alloc(PAGE_ALIGN(bytes), PAGE_SIZE);

	if (!start)

		panic("%s: Failed to allocate %lu bytes align=0x%lx\n",

		      __func__, PAGE_ALIGN(bytes), PAGE_SIZE);



	/*

	 * And replace that memory with pages under 4GB.

	 */

	rc = xen_swiotlb_fixup(start, bytes, nslabs);

	if (rc) {

		memblock_free(__pa(start), PAGE_ALIGN(bytes));

		if (repeat--) {

			/* Min is 2MB */

			nslabs = max(1024UL, (nslabs >> 1));

			pr_info("Lowering to %luMB\n",

				(nslabs << IO_TLB_SHIFT) >> 20);

			goto retry;

		}

		panic("%s (rc:%d)", xen_swiotlb_error(XEN_SWIOTLB_EFIXUP), rc);

	}



	if (swiotlb_init_with_tbl(start, nslabs, false))

		panic("Cannot allocate SWIOTLB buffer");

	swiotlb_set_max_segment(PAGE_SIZE);

}

#endif /* CONFIG_X86 */



static void *

xen_swiotlb_alloc_coherent(struct device *hwdev, size_t size,

			   dma_addr_t *dma_handle, gfp_t flags,

include/xen/swiotlb-xen.h

+2 −1
Original line number Diff line number Diff line
@@ -9,7 +9,8 @@ void xen_dma_sync_for_cpu(struct device *dev, dma_addr_t handle, 
void xen_dma_sync_for_device(struct device *dev, dma_addr_t handle,

			     size_t size, enum dma_data_direction dir);



extern int xen_swiotlb_init(int verbose, bool early);

int xen_swiotlb_init(void);

void __init xen_swiotlb_init_early(void);

extern const struct dma_map_ops xen_swiotlb_dma_ops;



#endif /* __LINUX_SWIOTLB_XEN_H */