um: Optimize TLB operations v2

Make the code to merge mmap/munmap/mprotect operations in tlb.c
common for userspace and kernel. Kernel tlb operations can now
be merged as well.

Signed-off-by: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

1 files changed, 57 insertions, 28 deletions

diff --git a/arch/um/kernel/tlb.c b/arch/um/kernel/tlb.c
index 37508b190106..b7f7a60a0928 100644
--- a/arch/um/kernel/tlb.c
+++ b/arch/um/kernel/tlb.c
@@ -37,17 +37,19 @@ struct host_vm_change {
                         } mprotect;
                 } u;
         } ops[1];
+        int userspace;
         int index;
-        struct mm_id *id;
+        struct mm_struct *mm;
         void *data;
         int force;
 };
 
-#define INIT_HVC(mm, force) \
+#define INIT_HVC(mm, force, userspace) \
         ((struct host_vm_change) \
          { .ops         = { { .type = NONE } }, \
-           .id          = &mm->context.id, \
+           .mm          = mm, \
            .data        = NULL, \
+           .userspace   = userspace, \
            .index       = 0, \
            .force       = force })
 
@@ -68,18 +70,40 @@ static int do_ops(struct host_vm_change *hvc, int end,
                 op = &hvc->ops[i];
                 switch (op->type) {
                 case MMAP:
-                        ret = map(hvc->id, op->u.mmap.addr, op->u.mmap.len,
-                                  op->u.mmap.prot, op->u.mmap.fd,
-                                  op->u.mmap.offset, finished, &hvc->data);
+                        if (hvc->userspace)
+                                ret = map(&hvc->mm->context.id, op->u.mmap.addr,
+                                          op->u.mmap.len, op->u.mmap.prot,
+                                          op->u.mmap.fd,
+                                          op->u.mmap.offset, finished,
+                                          &hvc->data);
+                        else
+                                map_memory(op->u.mmap.addr, op->u.mmap.offset,
+                                           op->u.mmap.len, 1, 1, 1);
                         break;
                 case MUNMAP:
-                        ret = unmap(hvc->id, op->u.munmap.addr,
-                                    op->u.munmap.len, finished, &hvc->data);
+                        if (hvc->userspace)
+                                ret = unmap(&hvc->mm->context.id,
+                                            op->u.munmap.addr,
+                                            op->u.munmap.len, finished,
+                                            &hvc->data);
+                        else
+                                ret = os_unmap_memory(
+                                        (void *) op->u.munmap.addr,
+                                                      op->u.munmap.len);
+
                         break;
                 case MPROTECT:
-                        ret = protect(hvc->id, op->u.mprotect.addr,
-                                      op->u.mprotect.len, op->u.mprotect.prot,
-                                      finished, &hvc->data);
+                        if (hvc->userspace)
+                                ret = protect(&hvc->mm->context.id,
+                                              op->u.mprotect.addr,
+                                              op->u.mprotect.len,
+                                              op->u.mprotect.prot,
+                                              finished, &hvc->data);
+                        else
+                                ret = os_protect_memory(
+                                        (void *) op->u.mprotect.addr,
+                                                        op->u.mprotect.len,
+                                                        1, 1, 1);
                         break;
                 default:
                         printk(KERN_ERR "Unknown op type %d in do_ops\n",
@@ -100,9 +124,12 @@ static int add_mmap(unsigned long virt, unsigned long phys, unsigned long len,
 {
         __u64 offset;
         struct host_vm_op *last;
-        int fd, ret = 0;
+        int fd = -1, ret = 0;
 
-        fd = phys_mapping(phys, &offset);
+        if (hvc->userspace)
+                fd = phys_mapping(phys, &offset);
+        else
+                offset = phys;
         if (hvc->index != 0) {
                 last = &hvc->ops[hvc->index - 1];
                 if ((last->type == MMAP) &&
@@ -277,9 +304,9 @@ void fix_range_common(struct mm_struct *mm, unsigned long start_addr,
         pgd_t *pgd;
         struct host_vm_change hvc;
         unsigned long addr = start_addr, next;
-        int ret = 0;
+        int ret = 0, userspace = 1;
 
-        hvc = INIT_HVC(mm, force);
+        hvc = INIT_HVC(mm, force, userspace);
         pgd = pgd_offset(mm, addr);
         do {
                 next = pgd_addr_end(addr, end_addr);
@@ -314,9 +341,11 @@ static int flush_tlb_kernel_range_common(unsigned long start, unsigned long end)
         pmd_t *pmd;
         pte_t *pte;
         unsigned long addr, last;
-        int updated = 0, err;
+        int updated = 0, err = 0, force = 0, userspace = 0;
+        struct host_vm_change hvc;
 
         mm = &init_mm;
+        hvc = INIT_HVC(mm, force, userspace);
         for (addr = start; addr < end;) {
                 pgd = pgd_offset(mm, addr);
                 if (!pgd_present(*pgd)) {
@@ -325,8 +354,7 @@ static int flush_tlb_kernel_range_common(unsigned long start, unsigned long end)
                                 last = end;
                         if (pgd_newpage(*pgd)) {
                                 updated = 1;
-                                err = os_unmap_memory((void *) addr,
-                                                      last - addr);
+                                err = add_munmap(addr, last - addr, &hvc);
                                 if (err < 0)
                                         panic("munmap failed, errno = %d\n",
                                               -err);
@@ -342,8 +370,7 @@ static int flush_tlb_kernel_range_common(unsigned long start, unsigned long end)
                                 last = end;
                         if (pud_newpage(*pud)) {
                                 updated = 1;
-                                err = os_unmap_memory((void *) addr,
-                                                      last - addr);
+                                err = add_munmap(addr, last - addr, &hvc);
                                 if (err < 0)
                                         panic("munmap failed, errno = %d\n",
                                               -err);
@@ -359,8 +386,7 @@ static int flush_tlb_kernel_range_common(unsigned long start, unsigned long end)
                                 last = end;
                         if (pmd_newpage(*pmd)) {
                                 updated = 1;
-                                err = os_unmap_memory((void *) addr,
-                                                      last - addr);
+                                err = add_munmap(addr, last - addr, &hvc);
                                 if (err < 0)
                                         panic("munmap failed, errno = %d\n",
                                               -err);
@@ -372,22 +398,25 @@ static int flush_tlb_kernel_range_common(unsigned long start, unsigned long end)
                 pte = pte_offset_kernel(pmd, addr);
                 if (!pte_present(*pte) || pte_newpage(*pte)) {
                         updated = 1;
-                        err = os_unmap_memory((void *) addr,
-                                              PAGE_SIZE);
+                        err = add_munmap(addr, PAGE_SIZE, &hvc);
                         if (err < 0)
                                 panic("munmap failed, errno = %d\n",
                                       -err);
                         if (pte_present(*pte))
-                                map_memory(addr,
-                                           pte_val(*pte) & PAGE_MASK,
-                                           PAGE_SIZE, 1, 1, 1);
+                                err = add_mmap(addr, pte_val(*pte) & PAGE_MASK,
+                                               PAGE_SIZE, 0, &hvc);
                 }
                 else if (pte_newprot(*pte)) {
                         updated = 1;
-                        os_protect_memory((void *) addr, PAGE_SIZE, 1, 1, 1);
+                        err = add_mprotect(addr, PAGE_SIZE, 0, &hvc);
                 }
                 addr += PAGE_SIZE;
         }
+        if (!err)
+                err = do_ops(&hvc, hvc.index, 1);
+
+        if (err < 0)
+                panic("flush_tlb_kernel failed, errno = %d\n", err);
         return updated;
 }