Merge branch 'stable/for-linus-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb
Pull swiotlb fixes from Konrad Rzeszutek Wilk:
"This has one fix to make i915 work when using Xen SWIOTLB, and a
feature from Geert to aid in debugging of devices that can't do DMA
outside the 32-bit address space.
The feature from Geert is on top of v4.10 merge window commit
(specifically you pulling my previous branch), as his changes were
dependent on the Documentation/ movement patches.
I figured it would just easier than me trying than to cherry-pick the
Documentation patches to satisfy git.
The patches have been soaking since 12/20, albeit I updated the last
patch due to linux-next catching an compiler error and adding an
Tested-and-Reported-by tag"
* 'stable/for-linus-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb:
swiotlb: Export swiotlb_max_segment to users
swiotlb: Add swiotlb=noforce debug option
swiotlb: Convert swiotlb_force from int to enum
x86, swiotlb: Simplify pci_swiotlb_detect_override()
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index d1eec5e..be7c0d9 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -3821,10 +3821,11 @@
it if 0 is given (See Documentation/cgroup-v1/memory.txt)
swiotlb= [ARM,IA-64,PPC,MIPS,X86]
- Format: { <int> | force }
+ Format: { <int> | force | noforce }
<int> -- Number of I/O TLB slabs
force -- force using of bounce buffers even if they
wouldn't be automatically used by the kernel
+ noforce -- Never use bounce buffers (for debugging)
switches= [HW,M68k]
diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c
index 290a84f..e040827 100644
--- a/arch/arm64/mm/dma-mapping.c
+++ b/arch/arm64/mm/dma-mapping.c
@@ -524,7 +524,8 @@
static int __init arm64_dma_init(void)
{
- if (swiotlb_force || max_pfn > (arm64_dma_phys_limit >> PAGE_SHIFT))
+ if (swiotlb_force == SWIOTLB_FORCE ||
+ max_pfn > (arm64_dma_phys_limit >> PAGE_SHIFT))
swiotlb = 1;
return atomic_pool_init();
diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
index 212c4d1..716d122 100644
--- a/arch/arm64/mm/init.c
+++ b/arch/arm64/mm/init.c
@@ -401,7 +401,8 @@
*/
void __init mem_init(void)
{
- if (swiotlb_force || max_pfn > (arm64_dma_phys_limit >> PAGE_SHIFT))
+ if (swiotlb_force == SWIOTLB_FORCE ||
+ max_pfn > (arm64_dma_phys_limit >> PAGE_SHIFT))
swiotlb_init(1);
set_max_mapnr(pfn_to_page(max_pfn) - mem_map);
diff --git a/arch/x86/kernel/pci-swiotlb.c b/arch/x86/kernel/pci-swiotlb.c
index b47edb8..410efb2 100644
--- a/arch/x86/kernel/pci-swiotlb.c
+++ b/arch/x86/kernel/pci-swiotlb.c
@@ -68,12 +68,10 @@
*/
int __init pci_swiotlb_detect_override(void)
{
- int use_swiotlb = swiotlb | swiotlb_force;
-
- if (swiotlb_force)
+ if (swiotlb_force == SWIOTLB_FORCE)
swiotlb = 1;
- return use_swiotlb;
+ return swiotlb;
}
IOMMU_INIT_FINISH(pci_swiotlb_detect_override,
pci_xen_swiotlb_detect,
diff --git a/arch/x86/xen/pci-swiotlb-xen.c b/arch/x86/xen/pci-swiotlb-xen.c
index a9fafb5..a0b36a9 100644
--- a/arch/x86/xen/pci-swiotlb-xen.c
+++ b/arch/x86/xen/pci-swiotlb-xen.c
@@ -48,7 +48,7 @@
* activate this IOMMU. If running as PV privileged, activate it
* irregardless.
*/
- if ((xen_initial_domain() || swiotlb || swiotlb_force))
+ if (xen_initial_domain() || swiotlb || swiotlb_force == SWIOTLB_FORCE)
xen_swiotlb = 1;
/* If we are running under Xen, we MUST disable the native SWIOTLB.
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 1e505d3..3dd7fc6 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -2306,15 +2306,6 @@
mutex_unlock(&obj->mm.lock);
}
-static unsigned int swiotlb_max_size(void)
-{
-#if IS_ENABLED(CONFIG_SWIOTLB)
- return rounddown(swiotlb_nr_tbl() << IO_TLB_SHIFT, PAGE_SIZE);
-#else
- return 0;
-#endif
-}
-
static void i915_sg_trim(struct sg_table *orig_st)
{
struct sg_table new_st;
@@ -2362,7 +2353,7 @@
GEM_BUG_ON(obj->base.read_domains & I915_GEM_GPU_DOMAINS);
GEM_BUG_ON(obj->base.write_domain & I915_GEM_GPU_DOMAINS);
- max_segment = swiotlb_max_size();
+ max_segment = swiotlb_max_segment();
if (!max_segment)
max_segment = rounddown(UINT_MAX, PAGE_SIZE);
diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c
index 478fb91..f905d6e 100644
--- a/drivers/xen/swiotlb-xen.c
+++ b/drivers/xen/swiotlb-xen.c
@@ -275,6 +275,10 @@
rc = 0;
} else
rc = swiotlb_late_init_with_tbl(xen_io_tlb_start, xen_io_tlb_nslabs);
+
+ if (!rc)
+ swiotlb_set_max_segment(PAGE_SIZE);
+
return rc;
error:
if (repeat--) {
@@ -392,7 +396,7 @@
if (dma_capable(dev, dev_addr, size) &&
!range_straddles_page_boundary(phys, size) &&
!xen_arch_need_swiotlb(dev, phys, dev_addr) &&
- !swiotlb_force) {
+ (swiotlb_force != SWIOTLB_FORCE)) {
/* we are not interested in the dma_addr returned by
* xen_dma_map_page, only in the potential cache flushes executed
* by the function. */
@@ -552,7 +556,7 @@
phys_addr_t paddr = sg_phys(sg);
dma_addr_t dev_addr = xen_phys_to_bus(paddr);
- if (swiotlb_force ||
+ if (swiotlb_force == SWIOTLB_FORCE ||
xen_arch_need_swiotlb(hwdev, paddr, dev_addr) ||
!dma_capable(hwdev, dev_addr, sg->length) ||
range_straddles_page_boundary(paddr, sg->length)) {
diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
index 183f37c..4ee479f 100644
--- a/include/linux/swiotlb.h
+++ b/include/linux/swiotlb.h
@@ -9,7 +9,13 @@
struct page;
struct scatterlist;
-extern int swiotlb_force;
+enum swiotlb_force {
+ SWIOTLB_NORMAL, /* Default - depending on HW DMA mask etc. */
+ SWIOTLB_FORCE, /* swiotlb=force */
+ SWIOTLB_NO_FORCE, /* swiotlb=noforce */
+};
+
+extern enum swiotlb_force swiotlb_force;
/*
* Maximum allowable number of contiguous slabs to map,
@@ -108,11 +114,14 @@
#ifdef CONFIG_SWIOTLB
extern void __init swiotlb_free(void);
+unsigned int swiotlb_max_segment(void);
#else
static inline void swiotlb_free(void) { }
+static inline unsigned int swiotlb_max_segment(void) { return 0; }
#endif
extern void swiotlb_print_info(void);
extern int is_swiotlb_buffer(phys_addr_t paddr);
+extern void swiotlb_set_max_segment(unsigned int);
#endif /* __LINUX_SWIOTLB_H */
diff --git a/include/trace/events/swiotlb.h b/include/trace/events/swiotlb.h
index 7ea4c5e..288c0c5 100644
--- a/include/trace/events/swiotlb.h
+++ b/include/trace/events/swiotlb.h
@@ -11,16 +11,16 @@
TP_PROTO(struct device *dev,
dma_addr_t dev_addr,
size_t size,
- int swiotlb_force),
+ enum swiotlb_force swiotlb_force),
TP_ARGS(dev, dev_addr, size, swiotlb_force),
TP_STRUCT__entry(
- __string( dev_name, dev_name(dev) )
- __field( u64, dma_mask )
- __field( dma_addr_t, dev_addr )
- __field( size_t, size )
- __field( int, swiotlb_force )
+ __string( dev_name, dev_name(dev) )
+ __field( u64, dma_mask )
+ __field( dma_addr_t, dev_addr )
+ __field( size_t, size )
+ __field( enum swiotlb_force, swiotlb_force )
),
TP_fast_assign(
@@ -37,7 +37,10 @@
__entry->dma_mask,
(unsigned long long)__entry->dev_addr,
__entry->size,
- __entry->swiotlb_force ? "swiotlb_force" : "" )
+ __print_symbolic(__entry->swiotlb_force,
+ { SWIOTLB_NORMAL, "NORMAL" },
+ { SWIOTLB_FORCE, "FORCE" },
+ { SWIOTLB_NO_FORCE, "NO_FORCE" }))
);
#endif /* _TRACE_SWIOTLB_H */
diff --git a/lib/swiotlb.c b/lib/swiotlb.c
index cb1b54e..975b8fc 100644
--- a/lib/swiotlb.c
+++ b/lib/swiotlb.c
@@ -53,7 +53,7 @@
*/
#define IO_TLB_MIN_SLABS ((1<<20) >> IO_TLB_SHIFT)
-int swiotlb_force;
+enum swiotlb_force swiotlb_force;
/*
* Used to do a quick range check in swiotlb_tbl_unmap_single and
@@ -83,6 +83,12 @@
static unsigned int io_tlb_index;
/*
+ * Max segment that we can provide which (if pages are contingous) will
+ * not be bounced (unless SWIOTLB_FORCE is set).
+ */
+unsigned int max_segment;
+
+/*
* We need to save away the original address corresponding to a mapped entry
* for the sync operations.
*/
@@ -106,8 +112,12 @@
}
if (*str == ',')
++str;
- if (!strcmp(str, "force"))
- swiotlb_force = 1;
+ if (!strcmp(str, "force")) {
+ swiotlb_force = SWIOTLB_FORCE;
+ } else if (!strcmp(str, "noforce")) {
+ swiotlb_force = SWIOTLB_NO_FORCE;
+ io_tlb_nslabs = 1;
+ }
return 0;
}
@@ -120,6 +130,20 @@
}
EXPORT_SYMBOL_GPL(swiotlb_nr_tbl);
+unsigned int swiotlb_max_segment(void)
+{
+ return max_segment;
+}
+EXPORT_SYMBOL_GPL(swiotlb_max_segment);
+
+void swiotlb_set_max_segment(unsigned int val)
+{
+ if (swiotlb_force == SWIOTLB_FORCE)
+ max_segment = 1;
+ else
+ max_segment = rounddown(val, PAGE_SIZE);
+}
+
/* default to 64MB */
#define IO_TLB_DEFAULT_SIZE (64UL<<20)
unsigned long swiotlb_size_or_default(void)
@@ -201,6 +225,7 @@
if (verbose)
swiotlb_print_info();
+ swiotlb_set_max_segment(io_tlb_nslabs << IO_TLB_SHIFT);
return 0;
}
@@ -279,6 +304,7 @@
rc = swiotlb_late_init_with_tbl(vstart, io_tlb_nslabs);
if (rc)
free_pages((unsigned long)vstart, order);
+
return rc;
}
@@ -333,6 +359,8 @@
late_alloc = 1;
+ swiotlb_set_max_segment(io_tlb_nslabs << IO_TLB_SHIFT);
+
return 0;
cleanup4:
@@ -347,6 +375,7 @@
io_tlb_end = 0;
io_tlb_start = 0;
io_tlb_nslabs = 0;
+ max_segment = 0;
return -ENOMEM;
}
@@ -375,6 +404,7 @@
PAGE_ALIGN(io_tlb_nslabs << IO_TLB_SHIFT));
}
io_tlb_nslabs = 0;
+ max_segment = 0;
}
int is_swiotlb_buffer(phys_addr_t paddr)
@@ -543,8 +573,15 @@
map_single(struct device *hwdev, phys_addr_t phys, size_t size,
enum dma_data_direction dir, unsigned long attrs)
{
- dma_addr_t start_dma_addr = phys_to_dma(hwdev, io_tlb_start);
+ dma_addr_t start_dma_addr;
+ if (swiotlb_force == SWIOTLB_NO_FORCE) {
+ dev_warn_ratelimited(hwdev, "Cannot do DMA to address %pa\n",
+ &phys);
+ return SWIOTLB_MAP_ERROR;
+ }
+
+ start_dma_addr = phys_to_dma(hwdev, io_tlb_start);
return swiotlb_tbl_map_single(hwdev, start_dma_addr, phys, size,
dir, attrs);
}
@@ -721,6 +758,9 @@
swiotlb_full(struct device *dev, size_t size, enum dma_data_direction dir,
int do_panic)
{
+ if (swiotlb_force == SWIOTLB_NO_FORCE)
+ return;
+
/*
* Ran out of IOMMU space for this operation. This is very bad.
* Unfortunately the drivers cannot handle this operation properly.
@@ -763,7 +803,7 @@
* we can safely return the device addr and not worry about bounce
* buffering it.
*/
- if (dma_capable(dev, dev_addr, size) && !swiotlb_force)
+ if (dma_capable(dev, dev_addr, size) && swiotlb_force != SWIOTLB_FORCE)
return dev_addr;
trace_swiotlb_bounced(dev, dev_addr, size, swiotlb_force);
@@ -904,7 +944,7 @@
phys_addr_t paddr = sg_phys(sg);
dma_addr_t dev_addr = phys_to_dma(hwdev, paddr);
- if (swiotlb_force ||
+ if (swiotlb_force == SWIOTLB_FORCE ||
!dma_capable(hwdev, dev_addr, sg->length)) {
phys_addr_t map = map_single(hwdev, sg_phys(sg),
sg->length, dir, attrs);