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Merge branch 'stable/xen-swiotlb-0.8.6' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen

Browse Source 
* 'stable/xen-swiotlb-0.8.6' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  x86: Detect whether we should use Xen SWIOTLB.
  pci-swiotlb-xen: Add glue code to setup dma_ops utilizing xen_swiotlb_* functions.
  swiotlb-xen: SWIOTLB library for Xen PV guest with PCI passthrough.
  xen/mmu: inhibit vmap aliases rather than trying to clear them out
  vmap: add flag to allow lazy unmap to be disabled at runtime
  xen: Add xen_create_contiguous_region
  xen: Rename the balloon lock
  xen: Allow unprivileged Xen domains to create iomap pages
  xen: use _PAGE_IOMAP in ioremap to do machine mappings

Fix up trivial conflicts (adding both xen swiotlb and xen pci platform
driver setup close to each other) in drivers/xen/{Kconfig,Makefile} and
include/xen/xen-ops.h
This commit is contained in:
Linus Torvalds 2010-08-12 09:09:41 -07:00
commit 26f0cf9181
16 changed files with 1024 additions and 24 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
arch/x86/include/asm/xen/page.h
View File

@ -112,13 +112,9 @@ static inline xpaddr_t machine_to_phys(xmaddr_t machine)
*/
static inline unsigned long mfn_to_local_pfn(unsigned long mfn)
{
extern unsigned long max_mapnr;
unsigned long pfn = mfn_to_pfn(mfn);
if ((pfn < max_mapnr)
&& !xen_feature(XENFEAT_auto_translated_physmap)
&& (get_phys_to_machine(pfn) != mfn))
return max_mapnr; /* force !pfn_valid() */
/* XXX fixme; not true with sparsemem */
if (get_phys_to_machine(pfn) != mfn)
return -1; /* force !pfn_valid() */
return pfn;
}

14
arch/x86/include/asm/xen/swiotlb-xen.h Normal file
View File

@ -0,0 +1,14 @@
#ifndef _ASM_X86_SWIOTLB_XEN_H
#define _ASM_X86_SWIOTLB_XEN_H
#ifdef CONFIG_SWIOTLB_XEN
extern int xen_swiotlb;
extern int __init pci_xen_swiotlb_detect(void);
extern void __init pci_xen_swiotlb_init(void);
#else
#define xen_swiotlb (0)
static inline int __init pci_xen_swiotlb_detect(void) { return 0; }
static inline void __init pci_xen_swiotlb_init(void) { }
#endif
#endif /* _ASM_X86_SWIOTLB_XEN_H */

7
arch/x86/kernel/pci-dma.c
View File

@ -13,6 +13,7 @@
#include <asm/calgary.h>
#include <asm/amd_iommu.h>
#include <asm/x86_init.h>
#include <asm/xen/swiotlb-xen.h>
static int forbid_dac __read_mostly;
@ -132,7 +133,7 @@ void __init pci_iommu_alloc(void)
/* free the range so iommu could get some range less than 4G */
dma32_free_bootmem();
if (pci_swiotlb_detect())
if (pci_xen_swiotlb_detect() || pci_swiotlb_detect())
goto out;
gart_iommu_hole_init();
@ -144,6 +145,8 @@ void __init pci_iommu_alloc(void)
/* needs to be called after gart_iommu_hole_init */
amd_iommu_detect();
out:
pci_xen_swiotlb_init();
pci_swiotlb_init();
}
@ -296,7 +299,7 @@ static int __init pci_iommu_init(void)
#endif
x86_init.iommu.iommu_init();
if (swiotlb) {
if (swiotlb || xen_swiotlb) {
printk(KERN_INFO "PCI-DMA: "
"Using software bounce buffering for IO (SWIOTLB)\n");
swiotlb_print_info();

1
arch/x86/xen/Makefile
View File

@ -18,3 +18,4 @@ obj-$(CONFIG_SMP) += smp.o
obj-$(CONFIG_PARAVIRT_SPINLOCKS)+= spinlock.o
obj-$(CONFIG_XEN_DEBUG_FS) += debugfs.o
obj-$(CONFIG_SWIOTLB_XEN) += pci-swiotlb-xen.o

4
arch/x86/xen/enlighten.c
View File

@ -1172,6 +1172,10 @@ asmlinkage void __init xen_start_kernel(void)
pgd = (pgd_t *)xen_start_info->pt_base;
if (!xen_initial_domain())
__supported_pte_mask &= ~(_PAGE_PWT | _PAGE_PCD);
__supported_pte_mask |= _PAGE_IOMAP;
/* Don't do the full vcpu_info placement stuff until we have a
possible map and a non-dummy shared_info. */
per_cpu(xen_vcpu, 0) = &HYPERVISOR_shared_info->vcpu_info[0];

293
arch/x86/xen/mmu.c
View File

@ -42,6 +42,7 @@
#include <linux/highmem.h>
#include <linux/debugfs.h>
#include <linux/bug.h>
#include <linux/vmalloc.h>
#include <linux/module.h>
#include <linux/gfp.h>
@ -51,15 +52,19 @@
#include <asm/mmu_context.h>
#include <asm/setup.h>
#include <asm/paravirt.h>
#include <asm/e820.h>
#include <asm/linkage.h>
#include <asm/page.h>
#include <asm/xen/hypercall.h>
#include <asm/xen/hypervisor.h>
#include <xen/xen.h>
#include <xen/page.h>
#include <xen/interface/xen.h>
#include <xen/interface/hvm/hvm_op.h>
#include <xen/interface/version.h>
#include <xen/interface/memory.h>
#include <xen/hvc-console.h>
#include "multicalls.h"
@ -68,6 +73,13 @@
#define MMU_UPDATE_HISTO 30
/*
* Protects atomic reservation decrease/increase against concurrent increases.
* Also protects non-atomic updates of current_pages and driver_pages, and
* balloon lists.
*/
DEFINE_SPINLOCK(xen_reservation_lock);
#ifdef CONFIG_XEN_DEBUG_FS
static struct {
@ -378,6 +390,28 @@ static bool xen_page_pinned(void *ptr)
return PagePinned(page);
}
static bool xen_iomap_pte(pte_t pte)
{
return pte_flags(pte) & _PAGE_IOMAP;
}
static void xen_set_iomap_pte(pte_t *ptep, pte_t pteval)
{
struct multicall_space mcs;
struct mmu_update *u;
mcs = xen_mc_entry(sizeof(*u));
u = mcs.args;
/* ptep might be kmapped when using 32-bit HIGHPTE */
u->ptr = arbitrary_virt_to_machine(ptep).maddr;
u->val = pte_val_ma(pteval);
MULTI_mmu_update(mcs.mc, mcs.args, 1, NULL, DOMID_IO);
xen_mc_issue(PARAVIRT_LAZY_MMU);
}
static void xen_extend_mmu_update(const struct mmu_update *update)
{
struct multicall_space mcs;
@ -454,6 +488,11 @@ void set_pte_mfn(unsigned long vaddr, unsigned long mfn, pgprot_t flags)
void xen_set_pte_at(struct mm_struct *mm, unsigned long addr,
pte_t *ptep, pte_t pteval)
{
if (xen_iomap_pte(pteval)) {
xen_set_iomap_pte(ptep, pteval);
goto out;
}
ADD_STATS(set_pte_at, 1);
// ADD_STATS(set_pte_at_pinned, xen_page_pinned(ptep));
ADD_STATS(set_pte_at_current, mm == current->mm);
@ -524,8 +563,25 @@ static pteval_t pte_pfn_to_mfn(pteval_t val)
return val;
}
static pteval_t iomap_pte(pteval_t val)
{
if (val & _PAGE_PRESENT) {
unsigned long pfn = (val & PTE_PFN_MASK) >> PAGE_SHIFT;
pteval_t flags = val & PTE_FLAGS_MASK;
/* We assume the pte frame number is a MFN, so
just use it as-is. */
val = ((pteval_t)pfn << PAGE_SHIFT) | flags;
}
return val;
}
pteval_t xen_pte_val(pte_t pte)
{
if (xen_initial_domain() && (pte.pte & _PAGE_IOMAP))
return pte.pte;
return pte_mfn_to_pfn(pte.pte);
}
PV_CALLEE_SAVE_REGS_THUNK(xen_pte_val);
@ -538,7 +594,22 @@ PV_CALLEE_SAVE_REGS_THUNK(xen_pgd_val);
pte_t xen_make_pte(pteval_t pte)
{
pte = pte_pfn_to_mfn(pte);
phys_addr_t addr = (pte & PTE_PFN_MASK);
/*
* Unprivileged domains are allowed to do IOMAPpings for
* PCI passthrough, but not map ISA space. The ISA
* mappings are just dummy local mappings to keep other
* parts of the kernel happy.
*/
if (unlikely(pte & _PAGE_IOMAP) &&
(xen_initial_domain() || addr >= ISA_END_ADDRESS)) {
pte = iomap_pte(pte);
} else {
pte &= ~_PAGE_IOMAP;
pte = pte_pfn_to_mfn(pte);
}
return native_make_pte(pte);
}
PV_CALLEE_SAVE_REGS_THUNK(xen_make_pte);
@ -594,6 +665,11 @@ void xen_set_pud(pud_t *ptr, pud_t val)
void xen_set_pte(pte_t *ptep, pte_t pte)
{
if (xen_iomap_pte(pte)) {
xen_set_iomap_pte(ptep, pte);
return;
}
ADD_STATS(pte_update, 1);
// ADD_STATS(pte_update_pinned, xen_page_pinned(ptep));
ADD_STATS(pte_update_batched, paravirt_get_lazy_mode() == PARAVIRT_LAZY_MMU);
@ -610,6 +686,11 @@ void xen_set_pte(pte_t *ptep, pte_t pte)
#ifdef CONFIG_X86_PAE
void xen_set_pte_atomic(pte_t *ptep, pte_t pte)
{
if (xen_iomap_pte(pte)) {
xen_set_iomap_pte(ptep, pte);
return;
}
set_64bit((u64 *)ptep, native_pte_val(pte));
}
@ -936,8 +1017,6 @@ static int xen_pin_page(struct mm_struct *mm, struct page *page,
read-only, and can be pinned. */
static void __xen_pgd_pin(struct mm_struct *mm, pgd_t *pgd)
{
vm_unmap_aliases();
xen_mc_batch();
if (__xen_pgd_walk(mm, pgd, xen_pin_page, USER_LIMIT)) {
@ -1501,7 +1580,6 @@ static void xen_alloc_ptpage(struct mm_struct *mm, unsigned long pfn, unsigned l
if (PagePinned(virt_to_page(mm->pgd))) {
SetPagePinned(page);
vm_unmap_aliases();
if (!PageHighMem(page)) {
make_lowmem_page_readonly(__va(PFN_PHYS((unsigned long)pfn)));
if (level == PT_PTE && USE_SPLIT_PTLOCKS)
@ -1812,9 +1890,16 @@ static void xen_set_fixmap(unsigned idx, phys_addr_t phys, pgprot_t prot)
pte = pfn_pte(phys, prot);
break;
default:
case FIX_PARAVIRT_BOOTMAP:
/* This is an MFN, but it isn't an IO mapping from the
IO domain */
pte = mfn_pte(phys, prot);
break;
default:
/* By default, set_fixmap is used for hardware mappings */
pte = mfn_pte(phys, __pgprot(pgprot_val(prot) | _PAGE_IOMAP));
break;
}
__native_set_fixmap(idx, pte);
@ -1940,8 +2025,206 @@ void __init xen_init_mmu_ops(void)
x86_init.paging.pagetable_setup_start = xen_pagetable_setup_start;
x86_init.paging.pagetable_setup_done = xen_pagetable_setup_done;
pv_mmu_ops = xen_mmu_ops;
vmap_lazy_unmap = false;
}
/* Protected by xen_reservation_lock. */
#define MAX_CONTIG_ORDER 9 /* 2MB */
static unsigned long discontig_frames[1<<MAX_CONTIG_ORDER];
#define VOID_PTE (mfn_pte(0, __pgprot(0)))
static void xen_zap_pfn_range(unsigned long vaddr, unsigned int order,
unsigned long *in_frames,
unsigned long *out_frames)
{
int i;
struct multicall_space mcs;
xen_mc_batch();
for (i = 0; i < (1UL<<order); i++, vaddr += PAGE_SIZE) {
mcs = __xen_mc_entry(0);
if (in_frames)
in_frames[i] = virt_to_mfn(vaddr);
MULTI_update_va_mapping(mcs.mc, vaddr, VOID_PTE, 0);
set_phys_to_machine(virt_to_pfn(vaddr), INVALID_P2M_ENTRY);
if (out_frames)
out_frames[i] = virt_to_pfn(vaddr);
}
xen_mc_issue(0);
}
/*
* Update the pfn-to-mfn mappings for a virtual address range, either to
* point to an array of mfns, or contiguously from a single starting
* mfn.
*/
static void xen_remap_exchanged_ptes(unsigned long vaddr, int order,
unsigned long *mfns,
unsigned long first_mfn)
{
unsigned i, limit;
unsigned long mfn;
xen_mc_batch();
limit = 1u << order;
for (i = 0; i < limit; i++, vaddr += PAGE_SIZE) {
struct multicall_space mcs;
unsigned flags;
mcs = __xen_mc_entry(0);
if (mfns)
mfn = mfns[i];
else
mfn = first_mfn + i;
if (i < (limit - 1))
flags = 0;
else {
if (order == 0)
flags = UVMF_INVLPG | UVMF_ALL;
else
flags = UVMF_TLB_FLUSH | UVMF_ALL;
}
MULTI_update_va_mapping(mcs.mc, vaddr,
mfn_pte(mfn, PAGE_KERNEL), flags);
set_phys_to_machine(virt_to_pfn(vaddr), mfn);
}
xen_mc_issue(0);
}
/*
* Perform the hypercall to exchange a region of our pfns to point to
* memory with the required contiguous alignment. Takes the pfns as
* input, and populates mfns as output.
*
* Returns a success code indicating whether the hypervisor was able to
* satisfy the request or not.
*/
static int xen_exchange_memory(unsigned long extents_in, unsigned int order_in,
unsigned long *pfns_in,
unsigned long extents_out,
unsigned int order_out,
unsigned long *mfns_out,
unsigned int address_bits)
{
long rc;
int success;
struct xen_memory_exchange exchange = {
.in = {
.nr_extents = extents_in,
.extent_order = order_in,
.extent_start = pfns_in,
.domid = DOMID_SELF
},
.out = {
.nr_extents = extents_out,
.extent_order = order_out,
.extent_start = mfns_out,
.address_bits = address_bits,
.domid = DOMID_SELF
}
};
BUG_ON(extents_in << order_in != extents_out << order_out);
rc = HYPERVISOR_memory_op(XENMEM_exchange, &exchange);
success = (exchange.nr_exchanged == extents_in);
BUG_ON(!success && ((exchange.nr_exchanged != 0) || (rc == 0)));
BUG_ON(success && (rc != 0));
return success;
}
int xen_create_contiguous_region(unsigned long vstart, unsigned int order,
unsigned int address_bits)
{
unsigned long *in_frames = discontig_frames, out_frame;
unsigned long flags;
int success;
/*
* Currently an auto-translated guest will not perform I/O, nor will
* it require PAE page directories below 4GB. Therefore any calls to
* this function are redundant and can be ignored.
*/
if (xen_feature(XENFEAT_auto_translated_physmap))
return 0;
if (unlikely(order > MAX_CONTIG_ORDER))
return -ENOMEM;
memset((void *) vstart, 0, PAGE_SIZE << order);
spin_lock_irqsave(&xen_reservation_lock, flags);
/* 1. Zap current PTEs, remembering MFNs. */
xen_zap_pfn_range(vstart, order, in_frames, NULL);
/* 2. Get a new contiguous memory extent. */
out_frame = virt_to_pfn(vstart);
success = xen_exchange_memory(1UL << order, 0, in_frames,
1, order, &out_frame,
address_bits);
/* 3. Map the new extent in place of old pages. */
if (success)
xen_remap_exchanged_ptes(vstart, order, NULL, out_frame);
else
xen_remap_exchanged_ptes(vstart, order, in_frames, 0);
spin_unlock_irqrestore(&xen_reservation_lock, flags);
return success ? 0 : -ENOMEM;
}
EXPORT_SYMBOL_GPL(xen_create_contiguous_region);
void xen_destroy_contiguous_region(unsigned long vstart, unsigned int order)
{
unsigned long *out_frames = discontig_frames, in_frame;
unsigned long flags;
int success;
if (xen_feature(XENFEAT_auto_translated_physmap))
return;
if (unlikely(order > MAX_CONTIG_ORDER))
return;
memset((void *) vstart, 0, PAGE_SIZE << order);
spin_lock_irqsave(&xen_reservation_lock, flags);
/* 1. Find start MFN of contiguous extent. */
in_frame = virt_to_mfn(vstart);
/* 2. Zap current PTEs. */
xen_zap_pfn_range(vstart, order, NULL, out_frames);
/* 3. Do the exchange for non-contiguous MFNs. */
success = xen_exchange_memory(1, order, &in_frame, 1UL << order,
0, out_frames, 0);
/* 4. Map new pages in place of old pages. */
if (success)
xen_remap_exchanged_ptes(vstart, order, out_frames, 0);
else
xen_remap_exchanged_ptes(vstart, order, NULL, in_frame);
spin_unlock_irqrestore(&xen_reservation_lock, flags);
}
EXPORT_SYMBOL_GPL(xen_destroy_contiguous_region);
#ifdef CONFIG_XEN_PVHVM
static void xen_hvm_exit_mmap(struct mm_struct *mm)
{

58
arch/x86/xen/pci-swiotlb-xen.c Normal file
View File

@ -0,0 +1,58 @@
/* Glue code to lib/swiotlb-xen.c */
#include <linux/dma-mapping.h>
#include <xen/swiotlb-xen.h>
#include <asm/xen/hypervisor.h>
#include <xen/xen.h>
int xen_swiotlb __read_mostly;
static struct dma_map_ops xen_swiotlb_dma_ops = {
.mapping_error = xen_swiotlb_dma_mapping_error,
.alloc_coherent = xen_swiotlb_alloc_coherent,
.free_coherent = xen_swiotlb_free_coherent,
.sync_single_for_cpu = xen_swiotlb_sync_single_for_cpu,
.sync_single_for_device = xen_swiotlb_sync_single_for_device,
.sync_sg_for_cpu = xen_swiotlb_sync_sg_for_cpu,
.sync_sg_for_device = xen_swiotlb_sync_sg_for_device,
.map_sg = xen_swiotlb_map_sg_attrs,
.unmap_sg = xen_swiotlb_unmap_sg_attrs,
.map_page = xen_swiotlb_map_page,
.unmap_page = xen_swiotlb_unmap_page,
.dma_supported = xen_swiotlb_dma_supported,
};
/*
* pci_xen_swiotlb_detect - set xen_swiotlb to 1 if necessary
*
* This returns non-zero if we are forced to use xen_swiotlb (by the boot
* option).
*/
int __init pci_xen_swiotlb_detect(void)
{
/* If running as PV guest, either iommu=soft, or swiotlb=force will
* activate this IOMMU. If running as PV privileged, activate it
* irregardlesss.
*/
if ((xen_initial_domain() || swiotlb || swiotlb_force) &&
(xen_pv_domain()))
xen_swiotlb = 1;
/* If we are running under Xen, we MUST disable the native SWIOTLB.
* Don't worry about swiotlb_force flag activating the native, as
* the 'swiotlb' flag is the only one turning it on. */
if (xen_pv_domain())
swiotlb = 0;
return xen_swiotlb;
}
void __init pci_xen_swiotlb_init(void)
{
if (xen_swiotlb) {
xen_swiotlb_init(1);
dma_ops = &xen_swiotlb_dma_ops;
}
}

5
drivers/xen/Kconfig
View File

@ -71,4 +71,9 @@ config XEN_PLATFORM_PCI
initializing xenbus and grant_table when running in a Xen HVM
domain. As a consequence this driver is required to run any Xen PV
frontend on Xen HVM.
config SWIOTLB_XEN
def_bool y
depends on SWIOTLB
endmenu

1
drivers/xen/Makefile
View File

@ -11,3 +11,4 @@ obj-$(CONFIG_XEN_DEV_EVTCHN) += evtchn.o
obj-$(CONFIG_XENFS) += xenfs/
obj-$(CONFIG_XEN_SYS_HYPERVISOR) += sys-hypervisor.o
obj-$(CONFIG_XEN_PLATFORM_PCI) += platform-pci.o
obj-$(CONFIG_SWIOTLB_XEN) += swiotlb-xen.o

15
drivers/xen/balloon.c
View File

@ -85,13 +85,6 @@ static struct sys_device balloon_sysdev;
static int register_balloon(struct sys_device *sysdev);
/*
* Protects atomic reservation decrease/increase against concurrent increases.
* Also protects non-atomic updates of current_pages and driver_pages, and
* balloon lists.
*/
static DEFINE_SPINLOCK(balloon_lock);
static struct balloon_stats balloon_stats;
/* We increase/decrease in batches which fit in a page */
@ -210,7 +203,7 @@ static int increase_reservation(unsigned long nr_pages)
if (nr_pages > ARRAY_SIZE(frame_list))
nr_pages = ARRAY_SIZE(frame_list);
spin_lock_irqsave(&balloon_lock, flags);
spin_lock_irqsave(&xen_reservation_lock, flags);
page = balloon_first_page();
for (i = 0; i < nr_pages; i++) {
@ -254,7 +247,7 @@ static int increase_reservation(unsigned long nr_pages)
balloon_stats.current_pages += rc;
out:
spin_unlock_irqrestore(&balloon_lock, flags);
spin_unlock_irqrestore(&xen_reservation_lock, flags);
return rc < 0 ? rc : rc != nr_pages;
}
@ -299,7 +292,7 @@ static int decrease_reservation(unsigned long nr_pages)
kmap_flush_unused();
flush_tlb_all();
spin_lock_irqsave(&balloon_lock, flags);
spin_lock_irqsave(&xen_reservation_lock, flags);
/* No more mappings: invalidate P2M and add to balloon. */
for (i = 0; i < nr_pages; i++) {
@ -315,7 +308,7 @@ static int decrease_reservation(unsigned long nr_pages)
balloon_stats.current_pages -= nr_pages;
spin_unlock_irqrestore(&balloon_lock, flags);
spin_unlock_irqrestore(&xen_reservation_lock, flags);
return need_sleep;
}

515
drivers/xen/swiotlb-xen.c Normal file
View File

@ -0,0 +1,515 @@
/*
* Copyright 2010
* by Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
*
* This code provides a IOMMU for Xen PV guests with PCI passthrough.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License v2.0 as published by
* the Free Software Foundation
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* PV guests under Xen are running in an non-contiguous memory architecture.
*
* When PCI pass-through is utilized, this necessitates an IOMMU for
* translating bus (DMA) to virtual and vice-versa and also providing a
* mechanism to have contiguous pages for device drivers operations (say DMA
* operations).
*
* Specifically, under Xen the Linux idea of pages is an illusion. It
* assumes that pages start at zero and go up to the available memory. To
* help with that, the Linux Xen MMU provides a lookup mechanism to
* translate the page frame numbers (PFN) to machine frame numbers (MFN)
* and vice-versa. The MFN are the "real" frame numbers. Furthermore
* memory is not contiguous. Xen hypervisor stitches memory for guests
* from different pools, which means there is no guarantee that PFN==MFN
* and PFN+1==MFN+1. Lastly with Xen 4.0, pages (in debug mode) are
* allocated in descending order (high to low), meaning the guest might
* never get any MFN's under the 4GB mark.
*
*/
#include <linux/bootmem.h>
#include <linux/dma-mapping.h>
#include <xen/swiotlb-xen.h>
#include <xen/page.h>
#include <xen/xen-ops.h>
/*
* Used to do a quick range check in swiotlb_tbl_unmap_single and
* swiotlb_tbl_sync_single_*, to see if the memory was in fact allocated by this
* API.
*/
static char *xen_io_tlb_start, *xen_io_tlb_end;
static unsigned long xen_io_tlb_nslabs;
/*
* Quick lookup value of the bus address of the IOTLB.
*/
u64 start_dma_addr;
static dma_addr_t xen_phys_to_bus(phys_addr_t paddr)
{
return phys_to_machine(XPADDR(paddr)).maddr;;
}
static phys_addr_t xen_bus_to_phys(dma_addr_t baddr)
{
return machine_to_phys(XMADDR(baddr)).paddr;
}
static dma_addr_t xen_virt_to_bus(void *address)
{
return xen_phys_to_bus(virt_to_phys(address));
}
static int check_pages_physically_contiguous(unsigned long pfn,
unsigned int offset,
size_t length)
{
unsigned long next_mfn;
int i;
int nr_pages;
next_mfn = pfn_to_mfn(pfn);
nr_pages = (offset + length + PAGE_SIZE-1) >> PAGE_SHIFT;
for (i = 1; i < nr_pages; i++) {
if (pfn_to_mfn(++pfn) != ++next_mfn)
return 0;
}
return 1;
}
static int range_straddles_page_boundary(phys_addr_t p, size_t size)
{
unsigned long pfn = PFN_DOWN(p);
unsigned int offset = p & ~PAGE_MASK;
if (offset + size <= PAGE_SIZE)
return 0;
if (check_pages_physically_contiguous(pfn, offset, size))
return 0;
return 1;
}
static int is_xen_swiotlb_buffer(dma_addr_t dma_addr)
{
unsigned long mfn = PFN_DOWN(dma_addr);
unsigned long pfn = mfn_to_local_pfn(mfn);
phys_addr_t paddr;
/* If the address is outside our domain, it CAN
* have the same virtual address as another address
* in our domain. Therefore _only_ check address within our domain.
*/
if (pfn_valid(pfn)) {
paddr = PFN_PHYS(pfn);
return paddr >= virt_to_phys(xen_io_tlb_start) &&
paddr < virt_to_phys(xen_io_tlb_end);
}
return 0;
}
static int max_dma_bits = 32;
static int
xen_swiotlb_fixup(void *buf, size_t size, unsigned long nslabs)
{
int i, rc;
int dma_bits;
dma_bits = get_order(IO_TLB_SEGSIZE << IO_TLB_SHIFT) + PAGE_SHIFT;
i = 0;
do {
int slabs = min(nslabs - i, (unsigned long)IO_TLB_SEGSIZE);
do {
rc = xen_create_contiguous_region(
(unsigned long)buf + (i << IO_TLB_SHIFT),
get_order(slabs << IO_TLB_SHIFT),
dma_bits);
} while (rc && dma_bits++ < max_dma_bits);
if (rc)
return rc;
i += slabs;
} while (i < nslabs);
return 0;
}
void __init xen_swiotlb_init(int verbose)
{
unsigned long bytes;
int rc;
xen_io_tlb_nslabs = (64 * 1024 * 1024 >> IO_TLB_SHIFT);
xen_io_tlb_nslabs = ALIGN(xen_io_tlb_nslabs, IO_TLB_SEGSIZE);
bytes = xen_io_tlb_nslabs << IO_TLB_SHIFT;
/*
* Get IO TLB memory from any location.
*/
xen_io_tlb_start = alloc_bootmem(bytes);
if (!xen_io_tlb_start)
panic("Cannot allocate SWIOTLB buffer");
xen_io_tlb_end = xen_io_tlb_start + bytes;
/*
* And replace that memory with pages under 4GB.
*/
rc = xen_swiotlb_fixup(xen_io_tlb_start,
bytes,
xen_io_tlb_nslabs);
if (rc)
goto error;
start_dma_addr = xen_virt_to_bus(xen_io_tlb_start);
swiotlb_init_with_tbl(xen_io_tlb_start, xen_io_tlb_nslabs, verbose);
return;
error:
panic("DMA(%d): Failed to exchange pages allocated for DMA with Xen! "\
"We either don't have the permission or you do not have enough"\
"free memory under 4GB!\n", rc);
}
void *
xen_swiotlb_alloc_coherent(struct device *hwdev, size_t size,
dma_addr_t *dma_handle, gfp_t flags)
{
void *ret;
int order = get_order(size);
u64 dma_mask = DMA_BIT_MASK(32);
unsigned long vstart;
/*
* Ignore region specifiers - the kernel's ideas of
* pseudo-phys memory layout has nothing to do with the
* machine physical layout. We can't allocate highmem
* because we can't return a pointer to it.
*/
flags &= ~(__GFP_DMA | __GFP_HIGHMEM);
if (dma_alloc_from_coherent(hwdev, size, dma_handle, &ret))
return ret;
vstart = __get_free_pages(flags, order);
ret = (void *)vstart;
if (hwdev && hwdev->coherent_dma_mask)
dma_mask = dma_alloc_coherent_mask(hwdev, flags);
if (ret) {
if (xen_create_contiguous_region(vstart, order,
fls64(dma_mask)) != 0) {
free_pages(vstart, order);
return NULL;
}
memset(ret, 0, size);
*dma_handle = virt_to_machine(ret).maddr;
}
return ret;
}
EXPORT_SYMBOL_GPL(xen_swiotlb_alloc_coherent);
void
xen_swiotlb_free_coherent(struct device *hwdev, size_t size, void *vaddr,
dma_addr_t dev_addr)
{
int order = get_order(size);
if (dma_release_from_coherent(hwdev, order, vaddr))
return;
xen_destroy_contiguous_region((unsigned long)vaddr, order);
free_pages((unsigned long)vaddr, order);
}
EXPORT_SYMBOL_GPL(xen_swiotlb_free_coherent);
/*
* Map a single buffer of the indicated size for DMA in streaming mode. The
* physical address to use is returned.
*
* Once the device is given the dma address, the device owns this memory until
* either xen_swiotlb_unmap_page or xen_swiotlb_dma_sync_single is performed.
*/
dma_addr_t xen_swiotlb_map_page(struct device *dev, struct page *page,
unsigned long offset, size_t size,
enum dma_data_direction dir,
struct dma_attrs *attrs)
{
phys_addr_t phys = page_to_phys(page) + offset;
dma_addr_t dev_addr = xen_phys_to_bus(phys);
void *map;
BUG_ON(dir == DMA_NONE);
/*
* If the address happens to be in the device's DMA window,
* we can safely return the device addr and not worry about bounce
* buffering it.
*/
if (dma_capable(dev, dev_addr, size) &&
!range_straddles_page_boundary(phys, size) && !swiotlb_force)
return dev_addr;
/*
* Oh well, have to allocate and map a bounce buffer.
*/
map = swiotlb_tbl_map_single(dev, start_dma_addr, phys, size, dir);
if (!map)
return DMA_ERROR_CODE;
dev_addr = xen_virt_to_bus(map);
/*
* Ensure that the address returned is DMA'ble
*/
if (!dma_capable(dev, dev_addr, size))
panic("map_single: bounce buffer is not DMA'ble");
return dev_addr;
}
EXPORT_SYMBOL_GPL(xen_swiotlb_map_page);
/*
* Unmap a single streaming mode DMA translation. The dma_addr and size must
* match what was provided for in a previous xen_swiotlb_map_page call. All
* other usages are undefined.
*
* After this call, reads by the cpu to the buffer are guaranteed to see
* whatever the device wrote there.
*/
static void xen_unmap_single(struct device *hwdev, dma_addr_t dev_addr,
size_t size, enum dma_data_direction dir)
{
phys_addr_t paddr = xen_bus_to_phys(dev_addr);
BUG_ON(dir == DMA_NONE);
/* NOTE: We use dev_addr here, not paddr! */
if (is_xen_swiotlb_buffer(dev_addr)) {
swiotlb_tbl_unmap_single(hwdev, phys_to_virt(paddr), size, dir);
return;
}
if (dir != DMA_FROM_DEVICE)
return;
/*
* phys_to_virt doesn't work with hihgmem page but we could
* call dma_mark_clean() with hihgmem page here. However, we
* are fine since dma_mark_clean() is null on POWERPC. We can
* make dma_mark_clean() take a physical address if necessary.
*/
dma_mark_clean(phys_to_virt(paddr), size);
}
void xen_swiotlb_unmap_page(struct device *hwdev, dma_addr_t dev_addr,
size_t size, enum dma_data_direction dir,
struct dma_attrs *attrs)
{
xen_unmap_single(hwdev, dev_addr, size, dir);
}
EXPORT_SYMBOL_GPL(xen_swiotlb_unmap_page);
/*
* Make physical memory consistent for a single streaming mode DMA translation
* after a transfer.
*
* If you perform a xen_swiotlb_map_page() but wish to interrogate the buffer
* using the cpu, yet do not wish to teardown the dma mapping, you must
* call this function before doing so. At the next point you give the dma
* address back to the card, you must first perform a
* xen_swiotlb_dma_sync_for_device, and then the device again owns the buffer
*/
static void
xen_swiotlb_sync_single(struct device *hwdev, dma_addr_t dev_addr,
size_t size, enum dma_data_direction dir,
enum dma_sync_target target)
{
phys_addr_t paddr = xen_bus_to_phys(dev_addr);
BUG_ON(dir == DMA_NONE);
/* NOTE: We use dev_addr here, not paddr! */
if (is_xen_swiotlb_buffer(dev_addr)) {
swiotlb_tbl_sync_single(hwdev, phys_to_virt(paddr), size, dir,
target);
return;
}
if (dir != DMA_FROM_DEVICE)
return;
dma_mark_clean(phys_to_virt(paddr), size);
}
void
xen_swiotlb_sync_single_for_cpu(struct device *hwdev, dma_addr_t dev_addr,
size_t size, enum dma_data_direction dir)
{
xen_swiotlb_sync_single(hwdev, dev_addr, size, dir, SYNC_FOR_CPU);
}
EXPORT_SYMBOL_GPL(xen_swiotlb_sync_single_for_cpu);
void
xen_swiotlb_sync_single_for_device(struct device *hwdev, dma_addr_t dev_addr,
size_t size, enum dma_data_direction dir)
{
xen_swiotlb_sync_single(hwdev, dev_addr, size, dir, SYNC_FOR_DEVICE);
}
EXPORT_SYMBOL_GPL(xen_swiotlb_sync_single_for_device);
/*
* Map a set of buffers described by scatterlist in streaming mode for DMA.
* This is the scatter-gather version of the above xen_swiotlb_map_page
* interface. Here the scatter gather list elements are each tagged with the
* appropriate dma address and length. They are obtained via
* sg_dma_{address,length}(SG).
*
* NOTE: An implementation may be able to use a smaller number of
* DMA address/length pairs than there are SG table elements.
* (for example via virtual mapping capabilities)
* The routine returns the number of addr/length pairs actually
* used, at most nents.
*
* Device ownership issues as mentioned above for xen_swiotlb_map_page are the
* same here.
*/
int
xen_swiotlb_map_sg_attrs(struct device *hwdev, struct scatterlist *sgl,
int nelems, enum dma_data_direction dir,
struct dma_attrs *attrs)
{
struct scatterlist *sg;
int i;
BUG_ON(dir == DMA_NONE);
for_each_sg(sgl, sg, nelems, i) {
phys_addr_t paddr = sg_phys(sg);
dma_addr_t dev_addr = xen_phys_to_bus(paddr);
if (swiotlb_force ||
!dma_capable(hwdev, dev_addr, sg->length) ||
range_straddles_page_boundary(paddr, sg->length)) {
void *map = swiotlb_tbl_map_single(hwdev,
start_dma_addr,
sg_phys(sg),
sg->length, dir);
if (!map) {
/* Don't panic here, we expect map_sg users
to do proper error handling. */
xen_swiotlb_unmap_sg_attrs(hwdev, sgl, i, dir,
attrs);
sgl[0].dma_length = 0;
return DMA_ERROR_CODE;
}
sg->dma_address = xen_virt_to_bus(map);
} else
sg->dma_address = dev_addr;
sg->dma_length = sg->length;
}
return nelems;
}
EXPORT_SYMBOL_GPL(xen_swiotlb_map_sg_attrs);
int
xen_swiotlb_map_sg(struct device *hwdev, struct scatterlist *sgl, int nelems,
enum dma_data_direction dir)
{
return xen_swiotlb_map_sg_attrs(hwdev, sgl, nelems, dir, NULL);
}
EXPORT_SYMBOL_GPL(xen_swiotlb_map_sg);
/*
* Unmap a set of streaming mode DMA translations. Again, cpu read rules
* concerning calls here are the same as for swiotlb_unmap_page() above.
*/
void
xen_swiotlb_unmap_sg_attrs(struct device *hwdev, struct scatterlist *sgl,
int nelems, enum dma_data_direction dir,
struct dma_attrs *attrs)
{
struct scatterlist *sg;
int i;
BUG_ON(dir == DMA_NONE);
for_each_sg(sgl, sg, nelems, i)
xen_unmap_single(hwdev, sg->dma_address, sg->dma_length, dir);
}
EXPORT_SYMBOL_GPL(xen_swiotlb_unmap_sg_attrs);
void
xen_swiotlb_unmap_sg(struct device *hwdev, struct scatterlist *sgl, int nelems,
enum dma_data_direction dir)
{
return xen_swiotlb_unmap_sg_attrs(hwdev, sgl, nelems, dir, NULL);
}
EXPORT_SYMBOL_GPL(xen_swiotlb_unmap_sg);
/*
* Make physical memory consistent for a set of streaming mode DMA translations
* after a transfer.
*
* The same as swiotlb_sync_single_* but for a scatter-gather list, same rules
* and usage.
*/
static void
xen_swiotlb_sync_sg(struct device *hwdev, struct scatterlist *sgl,
int nelems, enum dma_data_direction dir,
enum dma_sync_target target)
{
struct scatterlist *sg;
int i;
for_each_sg(sgl, sg, nelems, i)
xen_swiotlb_sync_single(hwdev, sg->dma_address,
sg->dma_length, dir, target);
}
void
xen_swiotlb_sync_sg_for_cpu(struct device *hwdev, struct scatterlist *sg,
int nelems, enum dma_data_direction dir)
{
xen_swiotlb_sync_sg(hwdev, sg, nelems, dir, SYNC_FOR_CPU);
}
EXPORT_SYMBOL_GPL(xen_swiotlb_sync_sg_for_cpu);
void
xen_swiotlb_sync_sg_for_device(struct device *hwdev, struct scatterlist *sg,
int nelems, enum dma_data_direction dir)
{
xen_swiotlb_sync_sg(hwdev, sg, nelems, dir, SYNC_FOR_DEVICE);
}
EXPORT_SYMBOL_GPL(xen_swiotlb_sync_sg_for_device);
int
xen_swiotlb_dma_mapping_error(struct device *hwdev, dma_addr_t dma_addr)
{
return !dma_addr;
}
EXPORT_SYMBOL_GPL(xen_swiotlb_dma_mapping_error);
/*
* Return whether the given device DMA address mask can be supported
* properly. For example, if your device can only drive the low 24-bits
* during bus mastering, then you would pass 0x00ffffff as the mask to
* this function.
*/
int
xen_swiotlb_dma_supported(struct device *hwdev, u64 mask)
{
return xen_virt_to_bus(xen_io_tlb_end - 1) <= mask;
}
EXPORT_SYMBOL_GPL(xen_swiotlb_dma_supported);

2
include/linux/vmalloc.h
View File

@ -7,6 +7,8 @@
struct vm_area_struct; /* vma defining user mapping in mm_types.h */
extern bool vmap_lazy_unmap;
/* bits in flags of vmalloc's vm_struct below */
#define VM_IOREMAP 0x00000001 /* ioremap() and friends */
#define VM_ALLOC 0x00000002 /* vmalloc() */

50
include/xen/interface/memory.h
View File

@ -9,6 +9,8 @@
#ifndef __XEN_PUBLIC_MEMORY_H__
#define __XEN_PUBLIC_MEMORY_H__
#include <linux/spinlock.h>
/*
* Increase or decrease the specified domain's memory reservation. Returns a
* -ve errcode on failure, or the # extents successfully allocated or freed.
@ -52,6 +54,48 @@ struct xen_memory_reservation {
};
DEFINE_GUEST_HANDLE_STRUCT(xen_memory_reservation);
/*
* An atomic exchange of memory pages. If return code is zero then
* @out.extent_list provides GMFNs of the newly-allocated memory.
* Returns zero on complete success, otherwise a negative error code.
* On complete success then always @nr_exchanged == @in.nr_extents.
* On partial success @nr_exchanged indicates how much work was done.
*/
#define XENMEM_exchange 11
struct xen_memory_exchange {
/*
* [IN] Details of memory extents to be exchanged (GMFN bases).
* Note that @in.address_bits is ignored and unused.
*/
struct xen_memory_reservation in;
/*
* [IN/OUT] Details of new memory extents.
* We require that:
* 1. @in.domid == @out.domid
* 2. @in.nr_extents << @in.extent_order ==
* @out.nr_extents << @out.extent_order
* 3. @in.extent_start and @out.extent_start lists must not overlap
* 4. @out.extent_start lists GPFN bases to be populated
* 5. @out.extent_start is overwritten with allocated GMFN bases
*/
struct xen_memory_reservation out;
/*
* [OUT] Number of input extents that were successfully exchanged:
* 1. The first @nr_exchanged input extents were successfully
* deallocated.
* 2. The corresponding first entries in the output extent list correctly
* indicate the GMFNs that were successfully exchanged.
* 3. All other input and output extents are untouched.
* 4. If not all input exents are exchanged then the return code of this
* command will be non-zero.
* 5. THIS FIELD MUST BE INITIALISED TO ZERO BY THE CALLER!
*/
unsigned long nr_exchanged;
};
DEFINE_GUEST_HANDLE_STRUCT(xen_memory_exchange);
/*
* Returns the maximum machine frame number of mapped RAM in this system.
* This command always succeeds (it never returns an error code).
@ -142,4 +186,10 @@ struct xen_translate_gpfn_list {
};
DEFINE_GUEST_HANDLE_STRUCT(xen_translate_gpfn_list);
/*
* Prevent the balloon driver from changing the memory reservation
* during a driver critical region.
*/
extern spinlock_t xen_reservation_lock;
#endif /* __XEN_PUBLIC_MEMORY_H__ */

65
include/xen/swiotlb-xen.h Normal file
View File

@ -0,0 +1,65 @@
#ifndef __LINUX_SWIOTLB_XEN_H
#define __LINUX_SWIOTLB_XEN_H
#include <linux/swiotlb.h>
extern void xen_swiotlb_init(int verbose);
extern void
*xen_swiotlb_alloc_coherent(struct device *hwdev, size_t size,
dma_addr_t *dma_handle, gfp_t flags);
extern void
xen_swiotlb_free_coherent(struct device *hwdev, size_t size,
void *vaddr, dma_addr_t dma_handle);
extern dma_addr_t xen_swiotlb_map_page(struct device *dev, struct page *page,
unsigned long offset, size_t size,
enum dma_data_direction dir,
struct dma_attrs *attrs);
extern void xen_swiotlb_unmap_page(struct device *hwdev, dma_addr_t dev_addr,
size_t size, enum dma_data_direction dir,
struct dma_attrs *attrs);
/*
extern int
xen_swiotlb_map_sg(struct device *hwdev, struct scatterlist *sg, int nents,
enum dma_data_direction dir);
extern void
xen_swiotlb_unmap_sg(struct device *hwdev, struct scatterlist *sg, int nents,
enum dma_data_direction dir);
*/
extern int
xen_swiotlb_map_sg_attrs(struct device *hwdev, struct scatterlist *sgl,
int nelems, enum dma_data_direction dir,
struct dma_attrs *attrs);
extern void
xen_swiotlb_unmap_sg_attrs(struct device *hwdev, struct scatterlist *sgl,
int nelems, enum dma_data_direction dir,
struct dma_attrs *attrs);
extern void
xen_swiotlb_sync_single_for_cpu(struct device *hwdev, dma_addr_t dev_addr,
size_t size, enum dma_data_direction dir);
extern void
xen_swiotlb_sync_sg_for_cpu(struct device *hwdev, struct scatterlist *sg,
int nelems, enum dma_data_direction dir);
extern void
xen_swiotlb_sync_single_for_device(struct device *hwdev, dma_addr_t dev_addr,
size_t size, enum dma_data_direction dir);
extern void
xen_swiotlb_sync_sg_for_device(struct device *hwdev, struct scatterlist *sg,
int nelems, enum dma_data_direction dir);
extern int
xen_swiotlb_dma_mapping_error(struct device *hwdev, dma_addr_t dma_addr);
extern int
xen_swiotlb_dma_supported(struct device *hwdev, u64 mask);
#endif /* __LINUX_SWIOTLB_XEN_H */

6
include/xen/xen-ops.h
View File

@ -17,4 +17,10 @@ void xen_arch_resume(void);
int xen_setup_shutdown_event(void);
extern unsigned long *xen_contiguous_bitmap;
int xen_create_contiguous_region(unsigned long vstart, unsigned int order,
unsigned int address_bits);
void xen_destroy_contiguous_region(unsigned long vstart, unsigned int order);
#endif /* INCLUDE_XEN_OPS_H */

4
mm/vmalloc.c
View File

@ -31,6 +31,7 @@
#include <asm/tlbflush.h>
#include <asm/shmparam.h>
bool vmap_lazy_unmap __read_mostly = true;
/*** Page table manipulation functions ***/
@ -502,6 +503,9 @@ static unsigned long lazy_max_pages(void)
{
unsigned int log;
if (!vmap_lazy_unmap)
return 0;
log = fls(num_online_cpus());
return log * (32UL * 1024 * 1024 / PAGE_SIZE);