#include <asm/mmu_context.h>
#include <asm/pgtable.h>
#include <asm/tsb.h>
+#include <asm/oplib.h>
extern struct tsb swapper_tsb[KERNEL_TSB_NENTRIES];
-static inline unsigned long tsb_hash(unsigned long vaddr, unsigned long nentries)
+static inline unsigned long tsb_hash(unsigned long vaddr, unsigned long hash_shift, unsigned long nentries)
{
- vaddr >>= PAGE_SHIFT;
+ vaddr >>= hash_shift;
return vaddr & (nentries - 1);
}
-static inline int tag_compare(unsigned long tag, unsigned long vaddr, unsigned long context)
+static inline int tag_compare(unsigned long tag, unsigned long vaddr)
{
- return (tag == ((vaddr >> 22) | (context << 48)));
+ return (tag == (vaddr >> 22));
}
/* TSB flushes need only occur on the processor initiating the address
unsigned long v;
for (v = start; v < end; v += PAGE_SIZE) {
- unsigned long hash = tsb_hash(v, KERNEL_TSB_NENTRIES);
+ unsigned long hash = tsb_hash(v, PAGE_SHIFT,
+ KERNEL_TSB_NENTRIES);
struct tsb *ent = &swapper_tsb[hash];
- if (tag_compare(ent->tag, v, 0)) {
- ent->tag = 0UL;
+ if (tag_compare(ent->tag, v)) {
+ ent->tag = (1UL << TSB_TAG_INVALID_BIT);
membar_storeload_storestore();
}
}
}
-void flush_tsb_user(struct mmu_gather *mp)
+static void __flush_tsb_one(struct mmu_gather *mp, unsigned long hash_shift, unsigned long tsb, unsigned long nentries)
{
- struct mm_struct *mm = mp->mm;
- struct tsb *tsb = mm->context.tsb;
- unsigned long nentries = mm->context.tsb_nentries;
- unsigned long ctx, base;
- int i;
-
- if (unlikely(!CTX_VALID(mm->context)))
- return;
-
- ctx = CTX_HWBITS(mm->context);
+ unsigned long i;
- if (tlb_type == cheetah_plus)
- base = __pa(tsb);
- else
- base = (unsigned long) tsb;
-
for (i = 0; i < mp->tlb_nr; i++) {
unsigned long v = mp->vaddrs[i];
unsigned long tag, ent, hash;
v &= ~0x1UL;
- hash = tsb_hash(v, nentries);
- ent = base + (hash * sizeof(struct tsb));
- tag = (v >> 22UL) | (ctx << 48UL);
+ hash = tsb_hash(v, hash_shift, nentries);
+ ent = tsb + (hash * sizeof(struct tsb));
+ tag = (v >> 22UL);
tsb_flush(ent, tag);
}
}
-static void setup_tsb_params(struct mm_struct *mm, unsigned long tsb_bytes)
+void flush_tsb_user(struct mmu_gather *mp)
+{
+ struct mm_struct *mm = mp->mm;
+ unsigned long nentries, base, flags;
+
+ spin_lock_irqsave(&mm->context.lock, flags);
+
+ base = (unsigned long) mm->context.tsb_block[MM_TSB_BASE].tsb;
+ nentries = mm->context.tsb_block[MM_TSB_BASE].tsb_nentries;
+ if (tlb_type == cheetah_plus || tlb_type == hypervisor)
+ base = __pa(base);
+ __flush_tsb_one(mp, PAGE_SHIFT, base, nentries);
+
+#ifdef CONFIG_HUGETLB_PAGE
+ if (mm->context.tsb_block[MM_TSB_HUGE].tsb) {
+ base = (unsigned long) mm->context.tsb_block[MM_TSB_HUGE].tsb;
+ nentries = mm->context.tsb_block[MM_TSB_HUGE].tsb_nentries;
+ if (tlb_type == cheetah_plus || tlb_type == hypervisor)
+ base = __pa(base);
+ __flush_tsb_one(mp, HPAGE_SHIFT, base, nentries);
+ }
+#endif
+ spin_unlock_irqrestore(&mm->context.lock, flags);
+}
+
+#if defined(CONFIG_SPARC64_PAGE_SIZE_8KB)
+#define HV_PGSZ_IDX_BASE HV_PGSZ_IDX_8K
+#define HV_PGSZ_MASK_BASE HV_PGSZ_MASK_8K
+#elif defined(CONFIG_SPARC64_PAGE_SIZE_64KB)
+#define HV_PGSZ_IDX_BASE HV_PGSZ_IDX_64K
+#define HV_PGSZ_MASK_BASE HV_PGSZ_MASK_64K
+#elif defined(CONFIG_SPARC64_PAGE_SIZE_512KB)
+#define HV_PGSZ_IDX_BASE HV_PGSZ_IDX_512K
+#define HV_PGSZ_MASK_BASE HV_PGSZ_MASK_512K
+#elif defined(CONFIG_SPARC64_PAGE_SIZE_4MB)
+#define HV_PGSZ_IDX_BASE HV_PGSZ_IDX_4MB
+#define HV_PGSZ_MASK_BASE HV_PGSZ_MASK_4MB
+#else
+#error Broken base page size setting...
+#endif
+
+#ifdef CONFIG_HUGETLB_PAGE
+#if defined(CONFIG_HUGETLB_PAGE_SIZE_64K)
+#define HV_PGSZ_IDX_HUGE HV_PGSZ_IDX_64K
+#define HV_PGSZ_MASK_HUGE HV_PGSZ_MASK_64K
+#elif defined(CONFIG_HUGETLB_PAGE_SIZE_512K)
+#define HV_PGSZ_IDX_HUGE HV_PGSZ_IDX_512K
+#define HV_PGSZ_MASK_HUGE HV_PGSZ_MASK_512K
+#elif defined(CONFIG_HUGETLB_PAGE_SIZE_4MB)
+#define HV_PGSZ_IDX_HUGE HV_PGSZ_IDX_4MB
+#define HV_PGSZ_MASK_HUGE HV_PGSZ_MASK_4MB
+#else
+#error Broken huge page size setting...
+#endif
+#endif
+
+static void setup_tsb_params(struct mm_struct *mm, unsigned long tsb_idx, unsigned long tsb_bytes)
{
unsigned long tsb_reg, base, tsb_paddr;
unsigned long page_sz, tte;
- mm->context.tsb_nentries = tsb_bytes / sizeof(struct tsb);
+ mm->context.tsb_block[tsb_idx].tsb_nentries =
+ tsb_bytes / sizeof(struct tsb);
base = TSBMAP_BASE;
- tte = (_PAGE_VALID | _PAGE_L | _PAGE_CP |
- _PAGE_CV | _PAGE_P | _PAGE_W);
- tsb_paddr = __pa(mm->context.tsb);
+ tte = pgprot_val(PAGE_KERNEL_LOCKED);
+ tsb_paddr = __pa(mm->context.tsb_block[tsb_idx].tsb);
BUG_ON(tsb_paddr & (tsb_bytes - 1UL));
/* Use the smallest page size that can map the whole TSB
#ifdef DCACHE_ALIASING_POSSIBLE
base += (tsb_paddr & 8192);
#endif
- tte |= _PAGE_SZ8K;
page_sz = 8192;
break;
case 8192 << 1:
tsb_reg = 0x1UL;
- tte |= _PAGE_SZ64K;
page_sz = 64 * 1024;
break;
case 8192 << 2:
tsb_reg = 0x2UL;
- tte |= _PAGE_SZ64K;
page_sz = 64 * 1024;
break;
case 8192 << 3:
tsb_reg = 0x3UL;
- tte |= _PAGE_SZ64K;
page_sz = 64 * 1024;
break;
case 8192 << 4:
tsb_reg = 0x4UL;
- tte |= _PAGE_SZ512K;
page_sz = 512 * 1024;
break;
case 8192 << 5:
tsb_reg = 0x5UL;
- tte |= _PAGE_SZ512K;
page_sz = 512 * 1024;
break;
case 8192 << 6:
tsb_reg = 0x6UL;
- tte |= _PAGE_SZ512K;
page_sz = 512 * 1024;
break;
case 8192 << 7:
tsb_reg = 0x7UL;
- tte |= _PAGE_SZ4MB;
page_sz = 4 * 1024 * 1024;
break;
default:
BUG();
};
+ tte |= pte_sz_bits(page_sz);
- if (tlb_type == cheetah_plus) {
+ if (tlb_type == cheetah_plus || tlb_type == hypervisor) {
/* Physical mapping, no locked TLB entry for TSB. */
tsb_reg |= tsb_paddr;
- mm->context.tsb_reg_val = tsb_reg;
- mm->context.tsb_map_vaddr = 0;
- mm->context.tsb_map_pte = 0;
+ mm->context.tsb_block[tsb_idx].tsb_reg_val = tsb_reg;
+ mm->context.tsb_block[tsb_idx].tsb_map_vaddr = 0;
+ mm->context.tsb_block[tsb_idx].tsb_map_pte = 0;
} else {
tsb_reg |= base;
tsb_reg |= (tsb_paddr & (page_sz - 1UL));
tte |= (tsb_paddr & ~(page_sz - 1UL));
- mm->context.tsb_reg_val = tsb_reg;
- mm->context.tsb_map_vaddr = base;
- mm->context.tsb_map_pte = tte;
+ mm->context.tsb_block[tsb_idx].tsb_reg_val = tsb_reg;
+ mm->context.tsb_block[tsb_idx].tsb_map_vaddr = base;
+ mm->context.tsb_block[tsb_idx].tsb_map_pte = tte;
}
-}
-
-/* The page tables are locked against modifications while this
- * runs.
- *
- * XXX do some prefetching...
- */
-static void copy_tsb(struct tsb *old_tsb, unsigned long old_size,
- struct tsb *new_tsb, unsigned long new_size)
-{
- unsigned long old_nentries = old_size / sizeof(struct tsb);
- unsigned long new_nentries = new_size / sizeof(struct tsb);
- unsigned long i;
+ /* Setup the Hypervisor TSB descriptor. */
+ if (tlb_type == hypervisor) {
+ struct hv_tsb_descr *hp = &mm->context.tsb_descr[tsb_idx];
- for (i = 0; i < old_nentries; i++) {
- register unsigned long tag asm("o4");
- register unsigned long pte asm("o5");
- unsigned long v, hash;
-
- if (tlb_type == cheetah_plus) {
- __asm__ __volatile__(
- "ldda [%2] %3, %0"
- : "=r" (tag), "=r" (pte)
- : "r" (__pa(&old_tsb[i])),
- "i" (ASI_QUAD_LDD_PHYS));
- } else {
- __asm__ __volatile__(
- "ldda [%2] %3, %0"
- : "=r" (tag), "=r" (pte)
- : "r" (&old_tsb[i]),
- "i" (ASI_NUCLEUS_QUAD_LDD));
- }
+ switch (tsb_idx) {
+ case MM_TSB_BASE:
+ hp->pgsz_idx = HV_PGSZ_IDX_BASE;
+ break;
+#ifdef CONFIG_HUGETLB_PAGE
+ case MM_TSB_HUGE:
+ hp->pgsz_idx = HV_PGSZ_IDX_HUGE;
+ break;
+#endif
+ default:
+ BUG();
+ };
+ hp->assoc = 1;
+ hp->num_ttes = tsb_bytes / 16;
+ hp->ctx_idx = 0;
+ switch (tsb_idx) {
+ case MM_TSB_BASE:
+ hp->pgsz_mask = HV_PGSZ_MASK_BASE;
+ break;
+#ifdef CONFIG_HUGETLB_PAGE
+ case MM_TSB_HUGE:
+ hp->pgsz_mask = HV_PGSZ_MASK_HUGE;
+ break;
+#endif
+ default:
+ BUG();
+ };
+ hp->tsb_base = tsb_paddr;
+ hp->resv = 0;
+ }
+}
- if (!tag || (tag & (1UL << TSB_TAG_LOCK_BIT)))
- continue;
+static kmem_cache_t *tsb_caches[8] __read_mostly;
- /* We only put base page size PTEs into the TSB,
- * but that might change in the future. This code
- * would need to be changed if we start putting larger
- * page size PTEs into there.
- */
- WARN_ON((pte & _PAGE_ALL_SZ_BITS) != _PAGE_SZBITS);
+static const char *tsb_cache_names[8] = {
+ "tsb_8KB",
+ "tsb_16KB",
+ "tsb_32KB",
+ "tsb_64KB",
+ "tsb_128KB",
+ "tsb_256KB",
+ "tsb_512KB",
+ "tsb_1MB",
+};
- /* The tag holds bits 22 to 63 of the virtual address
- * and the context. Clear out the context, and shift
- * up to make a virtual address.
- */
- v = (tag & ((1UL << 42UL) - 1UL)) << 22UL;
+void __init tsb_cache_init(void)
+{
+ unsigned long i;
- /* The implied bits of the tag (bits 13 to 21) are
- * determined by the TSB entry index, so fill that in.
- */
- v |= (i & (512UL - 1UL)) << 13UL;
-
- hash = tsb_hash(v, new_nentries);
- if (tlb_type == cheetah_plus) {
- __asm__ __volatile__(
- "stxa %0, [%1] %2\n\t"
- "stxa %3, [%4] %2"
- : /* no outputs */
- : "r" (tag),
- "r" (__pa(&new_tsb[hash].tag)),
- "i" (ASI_PHYS_USE_EC),
- "r" (pte),
- "r" (__pa(&new_tsb[hash].pte)));
- } else {
- new_tsb[hash].tag = tag;
- new_tsb[hash].pte = pte;
+ for (i = 0; i < 8; i++) {
+ unsigned long size = 8192 << i;
+ const char *name = tsb_cache_names[i];
+
+ tsb_caches[i] = kmem_cache_create(name,
+ size, size,
+ SLAB_HWCACHE_ALIGN |
+ SLAB_MUST_HWCACHE_ALIGN,
+ NULL, NULL);
+ if (!tsb_caches[i]) {
+ prom_printf("Could not create %s cache\n", name);
+ prom_halt();
}
}
}
-/* When the RSS of an address space exceeds mm->context.tsb_rss_limit,
- * update_mmu_cache() invokes this routine to try and grow the TSB.
+/* When the RSS of an address space exceeds tsb_rss_limit for a TSB,
+ * do_sparc64_fault() invokes this routine to try and grow it.
+ *
* When we reach the maximum TSB size supported, we stick ~0UL into
- * mm->context.tsb_rss_limit so the grow checks in update_mmu_cache()
+ * tsb_rss_limit for that TSB so the grow checks in do_sparc64_fault()
* will not trigger any longer.
*
* The TSB can be anywhere from 8K to 1MB in size, in increasing powers
* of two. The TSB must be aligned to it's size, so f.e. a 512K TSB
- * must be 512K aligned.
+ * must be 512K aligned. It also must be physically contiguous, so we
+ * cannot use vmalloc().
*
* The idea here is to grow the TSB when the RSS of the process approaches
* the number of entries that the current TSB can hold at once. Currently,
* we trigger when the RSS hits 3/4 of the TSB capacity.
*/
-void tsb_grow(struct mm_struct *mm, unsigned long rss, gfp_t gfp_flags)
+void tsb_grow(struct mm_struct *mm, unsigned long tsb_index, unsigned long rss)
{
unsigned long max_tsb_size = 1 * 1024 * 1024;
- unsigned long size, old_size;
- struct page *page;
- struct tsb *old_tsb;
+ unsigned long new_size, old_size, flags;
+ struct tsb *old_tsb, *new_tsb;
+ unsigned long new_cache_index, old_cache_index;
+ unsigned long new_rss_limit;
+ gfp_t gfp_flags;
if (max_tsb_size > (PAGE_SIZE << MAX_ORDER))
max_tsb_size = (PAGE_SIZE << MAX_ORDER);
- for (size = PAGE_SIZE; size < max_tsb_size; size <<= 1UL) {
- unsigned long n_entries = size / sizeof(struct tsb);
+ new_cache_index = 0;
+ for (new_size = 8192; new_size < max_tsb_size; new_size <<= 1UL) {
+ unsigned long n_entries = new_size / sizeof(struct tsb);
n_entries = (n_entries * 3) / 4;
if (n_entries > rss)
break;
+
+ new_cache_index++;
}
- page = alloc_pages(gfp_flags | __GFP_ZERO, get_order(size));
- if (unlikely(!page))
+ if (new_size == max_tsb_size)
+ new_rss_limit = ~0UL;
+ else
+ new_rss_limit = ((new_size / sizeof(struct tsb)) * 3) / 4;
+
+retry_tsb_alloc:
+ gfp_flags = GFP_KERNEL;
+ if (new_size > (PAGE_SIZE * 2))
+ gfp_flags = __GFP_NOWARN | __GFP_NORETRY;
+
+ new_tsb = kmem_cache_alloc(tsb_caches[new_cache_index], gfp_flags);
+ if (unlikely(!new_tsb)) {
+ /* Not being able to fork due to a high-order TSB
+ * allocation failure is very bad behavior. Just back
+ * down to a 0-order allocation and force no TSB
+ * growing for this address space.
+ */
+ if (mm->context.tsb_block[tsb_index].tsb == NULL &&
+ new_cache_index > 0) {
+ new_cache_index = 0;
+ new_size = 8192;
+ new_rss_limit = ~0UL;
+ goto retry_tsb_alloc;
+ }
+
+ /* If we failed on a TSB grow, we are under serious
+ * memory pressure so don't try to grow any more.
+ */
+ if (mm->context.tsb_block[tsb_index].tsb != NULL)
+ mm->context.tsb_block[tsb_index].tsb_rss_limit = ~0UL;
return;
+ }
- if (size == max_tsb_size)
- mm->context.tsb_rss_limit = ~0UL;
- else
- mm->context.tsb_rss_limit =
- ((size / sizeof(struct tsb)) * 3) / 4;
+ /* Mark all tags as invalid. */
+ tsb_init(new_tsb, new_size);
+
+ /* Ok, we are about to commit the changes. If we are
+ * growing an existing TSB the locking is very tricky,
+ * so WATCH OUT!
+ *
+ * We have to hold mm->context.lock while committing to the
+ * new TSB, this synchronizes us with processors in
+ * flush_tsb_user() and switch_mm() for this address space.
+ *
+ * But even with that lock held, processors run asynchronously
+ * accessing the old TSB via TLB miss handling. This is OK
+ * because those actions are just propagating state from the
+ * Linux page tables into the TSB, page table mappings are not
+ * being changed. If a real fault occurs, the processor will
+ * synchronize with us when it hits flush_tsb_user(), this is
+ * also true for the case where vmscan is modifying the page
+ * tables. The only thing we need to be careful with is to
+ * skip any locked TSB entries during copy_tsb().
+ *
+ * When we finish committing to the new TSB, we have to drop
+ * the lock and ask all other cpus running this address space
+ * to run tsb_context_switch() to see the new TSB table.
+ */
+ spin_lock_irqsave(&mm->context.lock, flags);
+
+ old_tsb = mm->context.tsb_block[tsb_index].tsb;
+ old_cache_index =
+ (mm->context.tsb_block[tsb_index].tsb_reg_val & 0x7UL);
+ old_size = (mm->context.tsb_block[tsb_index].tsb_nentries *
+ sizeof(struct tsb));
- old_tsb = mm->context.tsb;
- old_size = mm->context.tsb_nentries * sizeof(struct tsb);
- if (old_tsb)
- copy_tsb(old_tsb, old_size, page_address(page), size);
+ /* Handle multiple threads trying to grow the TSB at the same time.
+ * One will get in here first, and bump the size and the RSS limit.
+ * The others will get in here next and hit this check.
+ */
+ if (unlikely(old_tsb &&
+ (rss < mm->context.tsb_block[tsb_index].tsb_rss_limit))) {
+ spin_unlock_irqrestore(&mm->context.lock, flags);
+
+ kmem_cache_free(tsb_caches[new_cache_index], new_tsb);
+ return;
+ }
+
+ mm->context.tsb_block[tsb_index].tsb_rss_limit = new_rss_limit;
+
+ if (old_tsb) {
+ extern void copy_tsb(unsigned long old_tsb_base,
+ unsigned long old_tsb_size,
+ unsigned long new_tsb_base,
+ unsigned long new_tsb_size);
+ unsigned long old_tsb_base = (unsigned long) old_tsb;
+ unsigned long new_tsb_base = (unsigned long) new_tsb;
+
+ if (tlb_type == cheetah_plus || tlb_type == hypervisor) {
+ old_tsb_base = __pa(old_tsb_base);
+ new_tsb_base = __pa(new_tsb_base);
+ }
+ copy_tsb(old_tsb_base, old_size, new_tsb_base, new_size);
+ }
+
+ mm->context.tsb_block[tsb_index].tsb = new_tsb;
+ setup_tsb_params(mm, tsb_index, new_size);
- mm->context.tsb = page_address(page);
- setup_tsb_params(mm, size);
+ spin_unlock_irqrestore(&mm->context.lock, flags);
/* If old_tsb is NULL, we're being invoked for the first time
* from init_new_context().
*/
if (old_tsb) {
- /* Now force all other processors to reload the new
- * TSB state.
- */
- smp_tsb_sync(mm);
-
- /* Finally reload it on the local cpu. No further
- * references will remain to the old TSB and we can
- * thus free it up.
- */
+ /* Reload it on the local cpu. */
tsb_context_switch(mm);
- free_pages((unsigned long) old_tsb, get_order(old_size));
+ /* Now force other processors to do the same. */
+ smp_tsb_sync(mm);
+
+ /* Now it is safe to free the old tsb. */
+ kmem_cache_free(tsb_caches[old_cache_index], old_tsb);
}
}
int init_new_context(struct task_struct *tsk, struct mm_struct *mm)
{
- unsigned long initial_rss;
+#ifdef CONFIG_HUGETLB_PAGE
+ unsigned long huge_pte_count;
+#endif
+ unsigned int i;
+
+ spin_lock_init(&mm->context.lock);
mm->context.sparc64_ctx_val = 0UL;
+#ifdef CONFIG_HUGETLB_PAGE
+ /* We reset it to zero because the fork() page copying
+ * will re-increment the counters as the parent PTEs are
+ * copied into the child address space.
+ */
+ huge_pte_count = mm->context.huge_pte_count;
+ mm->context.huge_pte_count = 0;
+#endif
+
/* copy_mm() copies over the parent's mm_struct before calling
* us, so we need to zero out the TSB pointer or else tsb_grow()
* will be confused and think there is an older TSB to free up.
*/
- mm->context.tsb = NULL;
+ for (i = 0; i < MM_NUM_TSBS; i++)
+ mm->context.tsb_block[i].tsb = NULL;
/* If this is fork, inherit the parent's TSB size. We would
* grow it to that size on the first page fault anyways.
*/
- initial_rss = mm->context.tsb_nentries;
- if (initial_rss)
- initial_rss -= 1;
+ tsb_grow(mm, MM_TSB_BASE, get_mm_rss(mm));
- tsb_grow(mm, initial_rss, GFP_KERNEL);
+#ifdef CONFIG_HUGETLB_PAGE
+ if (unlikely(huge_pte_count))
+ tsb_grow(mm, MM_TSB_HUGE, huge_pte_count);
+#endif
- if (unlikely(!mm->context.tsb))
+ if (unlikely(!mm->context.tsb_block[MM_TSB_BASE].tsb))
return -ENOMEM;
return 0;
}
-void destroy_context(struct mm_struct *mm)
+static void tsb_destroy_one(struct tsb_config *tp)
{
- unsigned long size = mm->context.tsb_nentries * sizeof(struct tsb);
+ unsigned long cache_index;
- free_pages((unsigned long) mm->context.tsb, get_order(size));
+ if (!tp->tsb)
+ return;
+ cache_index = tp->tsb_reg_val & 0x7UL;
+ kmem_cache_free(tsb_caches[cache_index], tp->tsb);
+ tp->tsb = NULL;
+ tp->tsb_reg_val = 0UL;
+}
- /* We can remove these later, but for now it's useful
- * to catch any bogus post-destroy_context() references
- * to the TSB.
- */
- mm->context.tsb = NULL;
- mm->context.tsb_reg_val = 0UL;
+void destroy_context(struct mm_struct *mm)
+{
+ unsigned long flags, i;
+
+ for (i = 0; i < MM_NUM_TSBS; i++)
+ tsb_destroy_one(&mm->context.tsb_block[i]);
- spin_lock(&ctx_alloc_lock);
+ spin_lock_irqsave(&ctx_alloc_lock, flags);
if (CTX_VALID(mm->context)) {
unsigned long nr = CTX_NRBITS(mm->context);
mmu_context_bmap[nr>>6] &= ~(1UL << (nr & 63));
}
- spin_unlock(&ctx_alloc_lock);
+ spin_unlock_irqrestore(&ctx_alloc_lock, flags);
}