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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2016-10-20 00:10:27 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2016-10-20 00:10:27 -0300
commitd0b2f91bede3bd5e3d24dd6803e56eee959c1797 (patch)
tree7fee4ab0509879c373c4f2cbd5b8a5be5b4041ee /arch/mips/mm/c-r4k.c
parente914f8eb445e8f74b00303c19c2ffceaedd16a05 (diff)
Linux-libre 4.8.2-gnupck-4.8.2-gnu
Diffstat (limited to 'arch/mips/mm/c-r4k.c')
-rw-r--r--arch/mips/mm/c-r4k.c286
1 files changed, 228 insertions, 58 deletions
diff --git a/arch/mips/mm/c-r4k.c b/arch/mips/mm/c-r4k.c
index ef7f925dd..fa7d8d379 100644
--- a/arch/mips/mm/c-r4k.c
+++ b/arch/mips/mm/c-r4k.c
@@ -40,6 +40,51 @@
#include <asm/mips-cm.h>
/*
+ * Bits describing what cache ops an SMP callback function may perform.
+ *
+ * R4K_HIT - Virtual user or kernel address based cache operations. The
+ * active_mm must be checked before using user addresses, falling
+ * back to kmap.
+ * R4K_INDEX - Index based cache operations.
+ */
+
+#define R4K_HIT BIT(0)
+#define R4K_INDEX BIT(1)
+
+/**
+ * r4k_op_needs_ipi() - Decide if a cache op needs to be done on every core.
+ * @type: Type of cache operations (R4K_HIT or R4K_INDEX).
+ *
+ * Decides whether a cache op needs to be performed on every core in the system.
+ * This may change depending on the @type of cache operation, as well as the set
+ * of online CPUs, so preemption should be disabled by the caller to prevent CPU
+ * hotplug from changing the result.
+ *
+ * Returns: 1 if the cache operation @type should be done on every core in
+ * the system.
+ * 0 if the cache operation @type is globalized and only needs to
+ * be performed on a simple CPU.
+ */
+static inline bool r4k_op_needs_ipi(unsigned int type)
+{
+ /* The MIPS Coherence Manager (CM) globalizes address-based cache ops */
+ if (type == R4K_HIT && mips_cm_present())
+ return false;
+
+ /*
+ * Hardware doesn't globalize the required cache ops, so SMP calls may
+ * be needed, but only if there are foreign CPUs (non-siblings with
+ * separate caches).
+ */
+ /* cpu_foreign_map[] undeclared when !CONFIG_SMP */
+#ifdef CONFIG_SMP
+ return !cpumask_empty(&cpu_foreign_map[0]);
+#else
+ return false;
+#endif
+}
+
+/*
* Special Variant of smp_call_function for use by cache functions:
*
* o No return value
@@ -48,30 +93,17 @@
* primary cache.
* o doesn't disable interrupts on the local CPU
*/
-static inline void r4k_on_each_cpu(void (*func) (void *info), void *info)
+static inline void r4k_on_each_cpu(unsigned int type,
+ void (*func)(void *info), void *info)
{
preempt_disable();
-
- /*
- * The Coherent Manager propagates address-based cache ops to other
- * cores but not index-based ops. However, r4k_on_each_cpu is used
- * in both cases so there is no easy way to tell what kind of op is
- * executed to the other cores. The best we can probably do is
- * to restrict that call when a CM is not present because both
- * CM-based SMP protocols (CMP & CPS) restrict index-based cache ops.
- */
- if (!mips_cm_present())
- smp_call_function_many(&cpu_foreign_map, func, info, 1);
+ if (r4k_op_needs_ipi(type))
+ smp_call_function_many(&cpu_foreign_map[smp_processor_id()],
+ func, info, 1);
func(info);
preempt_enable();
}
-#if defined(CONFIG_MIPS_CMP) || defined(CONFIG_MIPS_CPS)
-#define cpu_has_safe_index_cacheops 0
-#else
-#define cpu_has_safe_index_cacheops 1
-#endif
-
/*
* Must die.
*/
@@ -462,22 +494,44 @@ static inline void local_r4k___flush_cache_all(void * args)
static void r4k___flush_cache_all(void)
{
- r4k_on_each_cpu(local_r4k___flush_cache_all, NULL);
+ r4k_on_each_cpu(R4K_INDEX, local_r4k___flush_cache_all, NULL);
}
-static inline int has_valid_asid(const struct mm_struct *mm)
+/**
+ * has_valid_asid() - Determine if an mm already has an ASID.
+ * @mm: Memory map.
+ * @type: R4K_HIT or R4K_INDEX, type of cache op.
+ *
+ * Determines whether @mm already has an ASID on any of the CPUs which cache ops
+ * of type @type within an r4k_on_each_cpu() call will affect. If
+ * r4k_on_each_cpu() does an SMP call to a single VPE in each core, then the
+ * scope of the operation is confined to sibling CPUs, otherwise all online CPUs
+ * will need to be checked.
+ *
+ * Must be called in non-preemptive context.
+ *
+ * Returns: 1 if the CPUs affected by @type cache ops have an ASID for @mm.
+ * 0 otherwise.
+ */
+static inline int has_valid_asid(const struct mm_struct *mm, unsigned int type)
{
-#ifdef CONFIG_MIPS_MT_SMP
- int i;
+ unsigned int i;
+ const cpumask_t *mask = cpu_present_mask;
- for_each_online_cpu(i)
+ /* cpu_sibling_map[] undeclared when !CONFIG_SMP */
+#ifdef CONFIG_SMP
+ /*
+ * If r4k_on_each_cpu does SMP calls, it does them to a single VPE in
+ * each foreign core, so we only need to worry about siblings.
+ * Otherwise we need to worry about all present CPUs.
+ */
+ if (r4k_op_needs_ipi(type))
+ mask = &cpu_sibling_map[smp_processor_id()];
+#endif
+ for_each_cpu(i, mask)
if (cpu_context(i, mm))
return 1;
-
return 0;
-#else
- return cpu_context(smp_processor_id(), mm);
-#endif
}
static void r4k__flush_cache_vmap(void)
@@ -490,12 +544,16 @@ static void r4k__flush_cache_vunmap(void)
r4k_blast_dcache();
}
+/*
+ * Note: flush_tlb_range() assumes flush_cache_range() sufficiently flushes
+ * whole caches when vma is executable.
+ */
static inline void local_r4k_flush_cache_range(void * args)
{
struct vm_area_struct *vma = args;
int exec = vma->vm_flags & VM_EXEC;
- if (!(has_valid_asid(vma->vm_mm)))
+ if (!has_valid_asid(vma->vm_mm, R4K_INDEX))
return;
/*
@@ -516,14 +574,14 @@ static void r4k_flush_cache_range(struct vm_area_struct *vma,
int exec = vma->vm_flags & VM_EXEC;
if (cpu_has_dc_aliases || exec)
- r4k_on_each_cpu(local_r4k_flush_cache_range, vma);
+ r4k_on_each_cpu(R4K_INDEX, local_r4k_flush_cache_range, vma);
}
static inline void local_r4k_flush_cache_mm(void * args)
{
struct mm_struct *mm = args;
- if (!has_valid_asid(mm))
+ if (!has_valid_asid(mm, R4K_INDEX))
return;
/*
@@ -548,7 +606,7 @@ static void r4k_flush_cache_mm(struct mm_struct *mm)
if (!cpu_has_dc_aliases)
return;
- r4k_on_each_cpu(local_r4k_flush_cache_mm, mm);
+ r4k_on_each_cpu(R4K_INDEX, local_r4k_flush_cache_mm, mm);
}
struct flush_cache_page_args {
@@ -573,10 +631,10 @@ static inline void local_r4k_flush_cache_page(void *args)
void *vaddr;
/*
- * If ownes no valid ASID yet, cannot possibly have gotten
+ * If owns no valid ASID yet, cannot possibly have gotten
* this page into the cache.
*/
- if (!has_valid_asid(mm))
+ if (!has_valid_asid(mm, R4K_HIT))
return;
addr &= PAGE_MASK;
@@ -643,7 +701,7 @@ static void r4k_flush_cache_page(struct vm_area_struct *vma,
args.addr = addr;
args.pfn = pfn;
- r4k_on_each_cpu(local_r4k_flush_cache_page, &args);
+ r4k_on_each_cpu(R4K_HIT, local_r4k_flush_cache_page, &args);
}
static inline void local_r4k_flush_data_cache_page(void * addr)
@@ -656,18 +714,23 @@ static void r4k_flush_data_cache_page(unsigned long addr)
if (in_atomic())
local_r4k_flush_data_cache_page((void *)addr);
else
- r4k_on_each_cpu(local_r4k_flush_data_cache_page, (void *) addr);
+ r4k_on_each_cpu(R4K_HIT, local_r4k_flush_data_cache_page,
+ (void *) addr);
}
struct flush_icache_range_args {
unsigned long start;
unsigned long end;
+ unsigned int type;
};
-static inline void local_r4k_flush_icache_range(unsigned long start, unsigned long end)
+static inline void __local_r4k_flush_icache_range(unsigned long start,
+ unsigned long end,
+ unsigned int type)
{
if (!cpu_has_ic_fills_f_dc) {
- if (end - start >= dcache_size) {
+ if (type == R4K_INDEX ||
+ (type & R4K_INDEX && end - start >= dcache_size)) {
r4k_blast_dcache();
} else {
R4600_HIT_CACHEOP_WAR_IMPL;
@@ -675,7 +738,8 @@ static inline void local_r4k_flush_icache_range(unsigned long start, unsigned lo
}
}
- if (end - start > icache_size)
+ if (type == R4K_INDEX ||
+ (type & R4K_INDEX && end - start > icache_size))
r4k_blast_icache();
else {
switch (boot_cpu_type()) {
@@ -701,23 +765,52 @@ static inline void local_r4k_flush_icache_range(unsigned long start, unsigned lo
#endif
}
+static inline void local_r4k_flush_icache_range(unsigned long start,
+ unsigned long end)
+{
+ __local_r4k_flush_icache_range(start, end, R4K_HIT | R4K_INDEX);
+}
+
static inline void local_r4k_flush_icache_range_ipi(void *args)
{
struct flush_icache_range_args *fir_args = args;
unsigned long start = fir_args->start;
unsigned long end = fir_args->end;
+ unsigned int type = fir_args->type;
- local_r4k_flush_icache_range(start, end);
+ __local_r4k_flush_icache_range(start, end, type);
}
static void r4k_flush_icache_range(unsigned long start, unsigned long end)
{
struct flush_icache_range_args args;
+ unsigned long size, cache_size;
args.start = start;
args.end = end;
+ args.type = R4K_HIT | R4K_INDEX;
- r4k_on_each_cpu(local_r4k_flush_icache_range_ipi, &args);
+ /*
+ * Indexed cache ops require an SMP call.
+ * Consider if that can or should be avoided.
+ */
+ preempt_disable();
+ if (r4k_op_needs_ipi(R4K_INDEX) && !r4k_op_needs_ipi(R4K_HIT)) {
+ /*
+ * If address-based cache ops don't require an SMP call, then
+ * use them exclusively for small flushes.
+ */
+ size = end - start;
+ cache_size = icache_size;
+ if (!cpu_has_ic_fills_f_dc) {
+ size *= 2;
+ cache_size += dcache_size;
+ }
+ if (size <= cache_size)
+ args.type &= ~R4K_INDEX;
+ }
+ r4k_on_each_cpu(args.type, local_r4k_flush_icache_range_ipi, &args);
+ preempt_enable();
instruction_hazard();
}
@@ -744,7 +837,7 @@ static void r4k_dma_cache_wback_inv(unsigned long addr, unsigned long size)
* subset property so we have to flush the primary caches
* explicitly
*/
- if (cpu_has_safe_index_cacheops && size >= dcache_size) {
+ if (size >= dcache_size) {
r4k_blast_dcache();
} else {
R4600_HIT_CACHEOP_WAR_IMPL;
@@ -781,7 +874,7 @@ static void r4k_dma_cache_inv(unsigned long addr, unsigned long size)
return;
}
- if (cpu_has_safe_index_cacheops && size >= dcache_size) {
+ if (size >= dcache_size) {
r4k_blast_dcache();
} else {
R4600_HIT_CACHEOP_WAR_IMPL;
@@ -794,25 +887,76 @@ static void r4k_dma_cache_inv(unsigned long addr, unsigned long size)
}
#endif /* CONFIG_DMA_NONCOHERENT || CONFIG_DMA_MAYBE_COHERENT */
+struct flush_cache_sigtramp_args {
+ struct mm_struct *mm;
+ struct page *page;
+ unsigned long addr;
+};
+
/*
* While we're protected against bad userland addresses we don't care
* very much about what happens in that case. Usually a segmentation
* fault will dump the process later on anyway ...
*/
-static void local_r4k_flush_cache_sigtramp(void * arg)
+static void local_r4k_flush_cache_sigtramp(void *args)
{
+ struct flush_cache_sigtramp_args *fcs_args = args;
+ unsigned long addr = fcs_args->addr;
+ struct page *page = fcs_args->page;
+ struct mm_struct *mm = fcs_args->mm;
+ int map_coherent = 0;
+ void *vaddr;
+
unsigned long ic_lsize = cpu_icache_line_size();
unsigned long dc_lsize = cpu_dcache_line_size();
unsigned long sc_lsize = cpu_scache_line_size();
- unsigned long addr = (unsigned long) arg;
+
+ /*
+ * If owns no valid ASID yet, cannot possibly have gotten
+ * this page into the cache.
+ */
+ if (!has_valid_asid(mm, R4K_HIT))
+ return;
+
+ if (mm == current->active_mm) {
+ vaddr = NULL;
+ } else {
+ /*
+ * Use kmap_coherent or kmap_atomic to do flushes for
+ * another ASID than the current one.
+ */
+ map_coherent = (cpu_has_dc_aliases &&
+ page_mapcount(page) &&
+ !Page_dcache_dirty(page));
+ if (map_coherent)
+ vaddr = kmap_coherent(page, addr);
+ else
+ vaddr = kmap_atomic(page);
+ addr = (unsigned long)vaddr + (addr & ~PAGE_MASK);
+ }
R4600_HIT_CACHEOP_WAR_IMPL;
- if (dc_lsize)
- protected_writeback_dcache_line(addr & ~(dc_lsize - 1));
- if (!cpu_icache_snoops_remote_store && scache_size)
- protected_writeback_scache_line(addr & ~(sc_lsize - 1));
+ if (!cpu_has_ic_fills_f_dc) {
+ if (dc_lsize)
+ vaddr ? flush_dcache_line(addr & ~(dc_lsize - 1))
+ : protected_writeback_dcache_line(
+ addr & ~(dc_lsize - 1));
+ if (!cpu_icache_snoops_remote_store && scache_size)
+ vaddr ? flush_scache_line(addr & ~(sc_lsize - 1))
+ : protected_writeback_scache_line(
+ addr & ~(sc_lsize - 1));
+ }
if (ic_lsize)
- protected_flush_icache_line(addr & ~(ic_lsize - 1));
+ vaddr ? flush_icache_line(addr & ~(ic_lsize - 1))
+ : protected_flush_icache_line(addr & ~(ic_lsize - 1));
+
+ if (vaddr) {
+ if (map_coherent)
+ kunmap_coherent();
+ else
+ kunmap_atomic(vaddr);
+ }
+
if (MIPS4K_ICACHE_REFILL_WAR) {
__asm__ __volatile__ (
".set push\n\t"
@@ -837,7 +981,23 @@ static void local_r4k_flush_cache_sigtramp(void * arg)
static void r4k_flush_cache_sigtramp(unsigned long addr)
{
- r4k_on_each_cpu(local_r4k_flush_cache_sigtramp, (void *) addr);
+ struct flush_cache_sigtramp_args args;
+ int npages;
+
+ down_read(&current->mm->mmap_sem);
+
+ npages = get_user_pages_fast(addr, 1, 0, &args.page);
+ if (npages < 1)
+ goto out;
+
+ args.mm = current->mm;
+ args.addr = addr;
+
+ r4k_on_each_cpu(R4K_HIT, local_r4k_flush_cache_sigtramp, &args);
+
+ put_page(args.page);
+out:
+ up_read(&current->mm->mmap_sem);
}
static void r4k_flush_icache_all(void)
@@ -851,6 +1011,15 @@ struct flush_kernel_vmap_range_args {
int size;
};
+static inline void local_r4k_flush_kernel_vmap_range_index(void *args)
+{
+ /*
+ * Aliases only affect the primary caches so don't bother with
+ * S-caches or T-caches.
+ */
+ r4k_blast_dcache();
+}
+
static inline void local_r4k_flush_kernel_vmap_range(void *args)
{
struct flush_kernel_vmap_range_args *vmra = args;
@@ -861,12 +1030,8 @@ static inline void local_r4k_flush_kernel_vmap_range(void *args)
* Aliases only affect the primary caches so don't bother with
* S-caches or T-caches.
*/
- if (cpu_has_safe_index_cacheops && size >= dcache_size)
- r4k_blast_dcache();
- else {
- R4600_HIT_CACHEOP_WAR_IMPL;
- blast_dcache_range(vaddr, vaddr + size);
- }
+ R4600_HIT_CACHEOP_WAR_IMPL;
+ blast_dcache_range(vaddr, vaddr + size);
}
static void r4k_flush_kernel_vmap_range(unsigned long vaddr, int size)
@@ -876,7 +1041,12 @@ static void r4k_flush_kernel_vmap_range(unsigned long vaddr, int size)
args.vaddr = (unsigned long) vaddr;
args.size = size;
- r4k_on_each_cpu(local_r4k_flush_kernel_vmap_range, &args);
+ if (size >= dcache_size)
+ r4k_on_each_cpu(R4K_INDEX,
+ local_r4k_flush_kernel_vmap_range_index, NULL);
+ else
+ r4k_on_each_cpu(R4K_HIT, local_r4k_flush_kernel_vmap_range,
+ &args);
}
static inline void rm7k_erratum31(void)
@@ -1206,7 +1376,7 @@ static void probe_pcache(void)
c->icache.linesz;
c->icache.waybit = __ffs(icache_size/c->icache.ways);
- if (config & 0x8) /* VI bit */
+ if (config & MIPS_CONF_VI)
c->icache.flags |= MIPS_CACHE_VTAG;
/*