Note that the cache flush loop in cpa_flush_*() is identical when we
use __cpa_addr(); this then means the two functions are virtually
identical except for the TLB flushing.

Fold these two functions into a single cpa_flush() call.

One pesky detail is that __change_page_attr_set_clr() modifies @cpa,
so we have to save and restore part of that to ensure we flush the
original range.

Signed-off-by: Peter Zijlstra (Intel) <pet...@infradead.org>
---
 arch/x86/mm/pageattr.c |   96 ++++++++++++++-----------------------------------
 1 file changed, 29 insertions(+), 67 deletions(-)

--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -244,7 +244,7 @@ static unsigned long __cpa_addr(struct c
        if (cpa->flags & CPA_ARRAY)
                return cpa->vaddr[idx];
 
-       return *cpa->vaddr;
+       return *cpa->vaddr + idx * PAGE_SIZE;
 }
 
 /*
@@ -304,50 +304,6 @@ static void cpa_flush_all(unsigned long
        on_each_cpu(__cpa_flush_all, (void *) cache, 1);
 }
 
-static bool cpa_check_flush_all(int cache)
-{
-       BUG_ON(irqs_disabled() && !early_boot_irqs_disabled);
-
-       if (cache && !static_cpu_has(X86_FEATURE_CLFLUSH)) {
-               cpa_flush_all(cache);
-               return true;
-       }
-
-       return false;
-}
-
-static void cpa_flush_range(unsigned long start, int numpages, int cache)
-{
-       unsigned int i, level;
-       unsigned long addr;
-
-       WARN_ON(PAGE_ALIGN(start) != start);
-
-       if (cpa_check_flush_all(cache))
-               return;
-
-       flush_tlb_kernel_range(start, start + PAGE_SIZE * numpages);
-
-       if (!cache)
-               return;
-
-       /*
-        * We only need to flush on one CPU,
-        * clflush is a MESI-coherent instruction that
-        * will cause all other CPUs to flush the same
-        * cachelines:
-        */
-       for (i = 0, addr = start; i < numpages; i++, addr += PAGE_SIZE) {
-               pte_t *pte = lookup_address(addr, &level);
-
-               /*
-                * Only flush present addresses:
-                */
-               if (pte && (pte_val(*pte) & _PAGE_PRESENT))
-                       clflush_cache_range((void *) addr, PAGE_SIZE);
-       }
-}
-
 void __cpa_flush_array(void *data)
 {
        struct cpa_data *cpa = data;
@@ -357,33 +313,37 @@ void __cpa_flush_array(void *data)
                __flush_tlb_one_kernel(__cpa_addr(cpa, i));
 }
 
-static void cpa_flush_array(struct cpa_data *cpa, int cache)
+static void cpa_flush(struct cpa_data *data, int cache)
 {
+       struct cpa_data *cpa = data;
        unsigned int i;
 
-       if (cpa_check_flush_all(cache))
+       BUG_ON(irqs_disabled() && !early_boot_irqs_disabled);
+
+       if (cache && !static_cpu_has(X86_FEATURE_CLFLUSH)) {
+               cpa_flush_all(cache);
                return;
+       }
 
-       if (cpa->numpages <= tlb_single_page_flush_ceiling)
-               on_each_cpu(__cpa_flush_array, cpa, 1);
-       else
-               flush_tlb_all();
+       if (cpa->flags & (CPA_PAGES_ARRAY | CPA_ARRAY)) {
+               if (cpa->numpages <= tlb_single_page_flush_ceiling)
+                       on_each_cpu(__cpa_flush_array, cpa, 1);
+               else
+                       flush_tlb_all();
+       } else {
+               unsigned long start = __cpa_addr(cpa, 0);
+
+               flush_tlb_kernel_range(start, start + PAGE_SIZE * 
cpa->numpages);
+       }
 
        if (!cache)
                return;
 
-       /*
-        * We only need to flush on one CPU,
-        * clflush is a MESI-coherent instruction that
-        * will cause all other CPUs to flush the same
-        * cachelines:
-        */
        for (i = 0; i < cpa->numpages; i++) {
                unsigned long addr = __cpa_addr(cpa, i);
                unsigned int level;
-               pte_t *pte;
 
-               pte = lookup_address(addr, &level);
+               pte_t *pte = lookup_address(addr, &level);
 
                /*
                 * Only flush present addresses:
@@ -1695,7 +1655,7 @@ static int change_page_attr_set_clr(unsi
 {
        struct cpa_data cpa;
        int ret, cache, checkalias;
-       unsigned long baddr = 0;
+       unsigned long baddr = *addr;
 
        memset(&cpa, 0, sizeof(cpa));
 
@@ -1781,11 +1741,11 @@ static int change_page_attr_set_clr(unsi
                goto out;
        }
 
-       if (cpa.flags & (CPA_PAGES_ARRAY | CPA_ARRAY))
-               cpa_flush_array(&cpa, cache);
-       else
-               cpa_flush_range(baddr, numpages, cache);
+       /* Reset @cpa so that we flush the original range. */
+       cpa.vaddr = &baddr;
+       cpa.numpages = numpages;
 
+       cpa_flush(&cpa, cache);
 out:
        return ret;
 }
@@ -2071,8 +2031,8 @@ int set_memory_global(unsigned long addr
 
 static int __set_memory_enc_dec(unsigned long addr, int numpages, bool enc)
 {
+       unsigned long start = addr;
        struct cpa_data cpa;
-       unsigned long start;
        int ret;
 
        /* Nothing to do if memory encryption is not active */
@@ -2099,7 +2059,7 @@ static int __set_memory_enc_dec(unsigned
        /*
         * Before changing the encryption attribute, we need to flush caches.
         */
-       cpa_flush_range(start, numpages, 1);
+       cpa_flush(&cpa, 1);
 
        ret = __change_page_attr_set_clr(&cpa, 1);
 
@@ -2110,7 +2070,9 @@ static int __set_memory_enc_dec(unsigned
         * in case TLB flushing gets optimized in the cpa_flush_range()
         * path use the same logic as above.
         */
-       cpa_flush_range(start, numpages, 0);
+       cpa.vaddr = &start;
+       cpa.numpages = numpages;
+       cpa_flush(&cpa, 0);
 
        return ret;
 }


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