Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 559 insertions, 0 deletions

diff --git a/arch/um/kernel/tlb.c b/arch/um/kernel/tlb.c
new file mode 100644
index 000000000..37508b190
--- /dev/null
+++ b/arch/um/kernel/tlb.c
@@ -0,0 +1,559 @@
+/*
+ * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
+ * Licensed under the GPL
+ */
+
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/sched/signal.h>
+
+#include <asm/pgtable.h>
+#include <asm/tlbflush.h>
+#include <as-layout.h>
+#include <mem_user.h>
+#include <os.h>
+#include <skas.h>
+#include <kern_util.h>
+
+struct host_vm_change {
+	struct host_vm_op {
+		enum { NONE, MMAP, MUNMAP, MPROTECT } type;
+		union {
+			struct {
+				unsigned long addr;
+				unsigned long len;
+				unsigned int prot;
+				int fd;
+				__u64 offset;
+			} mmap;
+			struct {
+				unsigned long addr;
+				unsigned long len;
+			} munmap;
+			struct {
+				unsigned long addr;
+				unsigned long len;
+				unsigned int prot;
+			} mprotect;
+		} u;
+	} ops[1];
+	int index;
+	struct mm_id *id;
+	void *data;
+	int force;
+};
+
+#define INIT_HVC(mm, force) \
+	((struct host_vm_change) \
+	 { .ops		= { { .type = NONE } },	\
+	   .id		= &mm->context.id, \
+       	   .data	= NULL, \
+	   .index	= 0, \
+	   .force	= force })
+
+static void report_enomem(void)
+{
+	printk(KERN_ERR "UML ran out of memory on the host side! "
+			"This can happen due to a memory limitation or "
+			"vm.max_map_count has been reached.\n");
+}
+
+static int do_ops(struct host_vm_change *hvc, int end,
+		  int finished)
+{
+	struct host_vm_op *op;
+	int i, ret = 0;
+
+	for (i = 0; i < end && !ret; i++) {
+		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);
+			break;
+		case MUNMAP:
+			ret = unmap(hvc->id, op->u.munmap.addr,
+				    op->u.munmap.len, finished, &hvc->data);
+			break;
+		case MPROTECT:
+			ret = protect(hvc->id, op->u.mprotect.addr,
+				      op->u.mprotect.len, op->u.mprotect.prot,
+				      finished, &hvc->data);
+			break;
+		default:
+			printk(KERN_ERR "Unknown op type %d in do_ops\n",
+			       op->type);
+			BUG();
+			break;
+		}
+	}
+
+	if (ret == -ENOMEM)
+		report_enomem();
+
+	return ret;
+}
+
+static int add_mmap(unsigned long virt, unsigned long phys, unsigned long len,
+		    unsigned int prot, struct host_vm_change *hvc)
+{
+	__u64 offset;
+	struct host_vm_op *last;
+	int fd, ret = 0;
+
+	fd = phys_mapping(phys, &offset);
+	if (hvc->index != 0) {
+		last = &hvc->ops[hvc->index - 1];
+		if ((last->type == MMAP) &&
+		   (last->u.mmap.addr + last->u.mmap.len == virt) &&
+		   (last->u.mmap.prot == prot) && (last->u.mmap.fd == fd) &&
+		   (last->u.mmap.offset + last->u.mmap.len == offset)) {
+			last->u.mmap.len += len;
+			return 0;
+		}
+	}
+
+	if (hvc->index == ARRAY_SIZE(hvc->ops)) {
+		ret = do_ops(hvc, ARRAY_SIZE(hvc->ops), 0);
+		hvc->index = 0;
+	}
+
+	hvc->ops[hvc->index++] = ((struct host_vm_op)
+				  { .type	= MMAP,
+				    .u = { .mmap = { .addr	= virt,
+						     .len	= len,
+						     .prot	= prot,
+						     .fd	= fd,
+						     .offset	= offset }
+			   } });
+	return ret;
+}
+
+static int add_munmap(unsigned long addr, unsigned long len,
+		      struct host_vm_change *hvc)
+{
+	struct host_vm_op *last;
+	int ret = 0;
+
+	if ((addr >= STUB_START) && (addr < STUB_END))
+		return -EINVAL;
+
+	if (hvc->index != 0) {
+		last = &hvc->ops[hvc->index - 1];
+		if ((last->type == MUNMAP) &&
+		   (last->u.munmap.addr + last->u.mmap.len == addr)) {
+			last->u.munmap.len += len;
+			return 0;
+		}
+	}
+
+	if (hvc->index == ARRAY_SIZE(hvc->ops)) {
+		ret = do_ops(hvc, ARRAY_SIZE(hvc->ops), 0);
+		hvc->index = 0;
+	}
+
+	hvc->ops[hvc->index++] = ((struct host_vm_op)
+				  { .type	= MUNMAP,
+			     	    .u = { .munmap = { .addr	= addr,
+						       .len	= len } } });
+	return ret;
+}
+
+static int add_mprotect(unsigned long addr, unsigned long len,
+			unsigned int prot, struct host_vm_change *hvc)
+{
+	struct host_vm_op *last;
+	int ret = 0;
+
+	if (hvc->index != 0) {
+		last = &hvc->ops[hvc->index - 1];
+		if ((last->type == MPROTECT) &&
+		   (last->u.mprotect.addr + last->u.mprotect.len == addr) &&
+		   (last->u.mprotect.prot == prot)) {
+			last->u.mprotect.len += len;
+			return 0;
+		}
+	}
+
+	if (hvc->index == ARRAY_SIZE(hvc->ops)) {
+		ret = do_ops(hvc, ARRAY_SIZE(hvc->ops), 0);
+		hvc->index = 0;
+	}
+
+	hvc->ops[hvc->index++] = ((struct host_vm_op)
+				  { .type	= MPROTECT,
+			     	    .u = { .mprotect = { .addr	= addr,
+							 .len	= len,
+							 .prot	= prot } } });
+	return ret;
+}
+
+#define ADD_ROUND(n, inc) (((n) + (inc)) & ~((inc) - 1))
+
+static inline int update_pte_range(pmd_t *pmd, unsigned long addr,
+				   unsigned long end,
+				   struct host_vm_change *hvc)
+{
+	pte_t *pte;
+	int r, w, x, prot, ret = 0;
+
+	pte = pte_offset_kernel(pmd, addr);
+	do {
+		if ((addr >= STUB_START) && (addr < STUB_END))
+			continue;
+
+		r = pte_read(*pte);
+		w = pte_write(*pte);
+		x = pte_exec(*pte);
+		if (!pte_young(*pte)) {
+			r = 0;
+			w = 0;
+		} else if (!pte_dirty(*pte))
+			w = 0;
+
+		prot = ((r ? UM_PROT_READ : 0) | (w ? UM_PROT_WRITE : 0) |
+			(x ? UM_PROT_EXEC : 0));
+		if (hvc->force || pte_newpage(*pte)) {
+			if (pte_present(*pte))
+				ret = add_mmap(addr, pte_val(*pte) & PAGE_MASK,
+					       PAGE_SIZE, prot, hvc);
+			else
+				ret = add_munmap(addr, PAGE_SIZE, hvc);
+		} else if (pte_newprot(*pte))
+			ret = add_mprotect(addr, PAGE_SIZE, prot, hvc);
+		*pte = pte_mkuptodate(*pte);
+	} while (pte++, addr += PAGE_SIZE, ((addr < end) && !ret));
+	return ret;
+}
+
+static inline int update_pmd_range(pud_t *pud, unsigned long addr,
+				   unsigned long end,
+				   struct host_vm_change *hvc)
+{
+	pmd_t *pmd;
+	unsigned long next;
+	int ret = 0;
+
+	pmd = pmd_offset(pud, addr);
+	do {
+		next = pmd_addr_end(addr, end);
+		if (!pmd_present(*pmd)) {
+			if (hvc->force || pmd_newpage(*pmd)) {
+				ret = add_munmap(addr, next - addr, hvc);
+				pmd_mkuptodate(*pmd);
+			}
+		}
+		else ret = update_pte_range(pmd, addr, next, hvc);
+	} while (pmd++, addr = next, ((addr < end) && !ret));
+	return ret;
+}
+
+static inline int update_pud_range(pgd_t *pgd, unsigned long addr,
+				   unsigned long end,
+				   struct host_vm_change *hvc)
+{
+	pud_t *pud;
+	unsigned long next;
+	int ret = 0;
+
+	pud = pud_offset(pgd, addr);
+	do {
+		next = pud_addr_end(addr, end);
+		if (!pud_present(*pud)) {
+			if (hvc->force || pud_newpage(*pud)) {
+				ret = add_munmap(addr, next - addr, hvc);
+				pud_mkuptodate(*pud);
+			}
+		}
+		else ret = update_pmd_range(pud, addr, next, hvc);
+	} while (pud++, addr = next, ((addr < end) && !ret));
+	return ret;
+}
+
+void fix_range_common(struct mm_struct *mm, unsigned long start_addr,
+		      unsigned long end_addr, int force)
+{
+	pgd_t *pgd;
+	struct host_vm_change hvc;
+	unsigned long addr = start_addr, next;
+	int ret = 0;
+
+	hvc = INIT_HVC(mm, force);
+	pgd = pgd_offset(mm, addr);
+	do {
+		next = pgd_addr_end(addr, end_addr);
+		if (!pgd_present(*pgd)) {
+			if (force || pgd_newpage(*pgd)) {
+				ret = add_munmap(addr, next - addr, &hvc);
+				pgd_mkuptodate(*pgd);
+			}
+		}
+		else ret = update_pud_range(pgd, addr, next, &hvc);
+	} while (pgd++, addr = next, ((addr < end_addr) && !ret));
+
+	if (!ret)
+		ret = do_ops(&hvc, hvc.index, 1);
+
+	/* This is not an else because ret is modified above */
+	if (ret) {
+		printk(KERN_ERR "fix_range_common: failed, killing current "
+		       "process: %d\n", task_tgid_vnr(current));
+		/* We are under mmap_sem, release it such that current can terminate */
+		up_write(&current->mm->mmap_sem);
+		force_sig(SIGKILL, current);
+		do_signal(&current->thread.regs);
+	}
+}
+
+static int flush_tlb_kernel_range_common(unsigned long start, unsigned long end)
+{
+	struct mm_struct *mm;
+	pgd_t *pgd;
+	pud_t *pud;
+	pmd_t *pmd;
+	pte_t *pte;
+	unsigned long addr, last;
+	int updated = 0, err;
+
+	mm = &init_mm;
+	for (addr = start; addr < end;) {
+		pgd = pgd_offset(mm, addr);
+		if (!pgd_present(*pgd)) {
+			last = ADD_ROUND(addr, PGDIR_SIZE);
+			if (last > end)
+				last = end;
+			if (pgd_newpage(*pgd)) {
+				updated = 1;
+				err = os_unmap_memory((void *) addr,
+						      last - addr);
+				if (err < 0)
+					panic("munmap failed, errno = %d\n",
+					      -err);
+			}
+			addr = last;
+			continue;
+		}
+
+		pud = pud_offset(pgd, addr);
+		if (!pud_present(*pud)) {
+			last = ADD_ROUND(addr, PUD_SIZE);
+			if (last > end)
+				last = end;
+			if (pud_newpage(*pud)) {
+				updated = 1;
+				err = os_unmap_memory((void *) addr,
+						      last - addr);
+				if (err < 0)
+					panic("munmap failed, errno = %d\n",
+					      -err);
+			}
+			addr = last;
+			continue;
+		}
+
+		pmd = pmd_offset(pud, addr);
+		if (!pmd_present(*pmd)) {
+			last = ADD_ROUND(addr, PMD_SIZE);
+			if (last > end)
+				last = end;
+			if (pmd_newpage(*pmd)) {
+				updated = 1;
+				err = os_unmap_memory((void *) addr,
+						      last - addr);
+				if (err < 0)
+					panic("munmap failed, errno = %d\n",
+					      -err);
+			}
+			addr = last;
+			continue;
+		}
+
+		pte = pte_offset_kernel(pmd, addr);
+		if (!pte_present(*pte) || pte_newpage(*pte)) {
+			updated = 1;
+			err = os_unmap_memory((void *) addr,
+					      PAGE_SIZE);
+			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);
+		}
+		else if (pte_newprot(*pte)) {
+			updated = 1;
+			os_protect_memory((void *) addr, PAGE_SIZE, 1, 1, 1);
+		}
+		addr += PAGE_SIZE;
+	}
+	return updated;
+}
+
+void flush_tlb_page(struct vm_area_struct *vma, unsigned long address)
+{
+	pgd_t *pgd;
+	pud_t *pud;
+	pmd_t *pmd;
+	pte_t *pte;
+	struct mm_struct *mm = vma->vm_mm;
+	void *flush = NULL;
+	int r, w, x, prot, err = 0;
+	struct mm_id *mm_id;
+
+	address &= PAGE_MASK;
+	pgd = pgd_offset(mm, address);
+	if (!pgd_present(*pgd))
+		goto kill;
+
+	pud = pud_offset(pgd, address);
+	if (!pud_present(*pud))
+		goto kill;
+
+	pmd = pmd_offset(pud, address);
+	if (!pmd_present(*pmd))
+		goto kill;
+
+	pte = pte_offset_kernel(pmd, address);
+
+	r = pte_read(*pte);
+	w = pte_write(*pte);
+	x = pte_exec(*pte);
+	if (!pte_young(*pte)) {
+		r = 0;
+		w = 0;
+	} else if (!pte_dirty(*pte)) {
+		w = 0;
+	}
+
+	mm_id = &mm->context.id;
+	prot = ((r ? UM_PROT_READ : 0) | (w ? UM_PROT_WRITE : 0) |
+		(x ? UM_PROT_EXEC : 0));
+	if (pte_newpage(*pte)) {
+		if (pte_present(*pte)) {
+			unsigned long long offset;
+			int fd;
+
+			fd = phys_mapping(pte_val(*pte) & PAGE_MASK, &offset);
+			err = map(mm_id, address, PAGE_SIZE, prot, fd, offset,
+				  1, &flush);
+		}
+		else err = unmap(mm_id, address, PAGE_SIZE, 1, &flush);
+	}
+	else if (pte_newprot(*pte))
+		err = protect(mm_id, address, PAGE_SIZE, prot, 1, &flush);
+
+	if (err) {
+		if (err == -ENOMEM)
+			report_enomem();
+
+		goto kill;
+	}
+
+	*pte = pte_mkuptodate(*pte);
+
+	return;
+
+kill:
+	printk(KERN_ERR "Failed to flush page for address 0x%lx\n", address);
+	force_sig(SIGKILL, current);
+}
+
+pgd_t *pgd_offset_proc(struct mm_struct *mm, unsigned long address)
+{
+	return pgd_offset(mm, address);
+}
+
+pud_t *pud_offset_proc(pgd_t *pgd, unsigned long address)
+{
+	return pud_offset(pgd, address);
+}
+
+pmd_t *pmd_offset_proc(pud_t *pud, unsigned long address)
+{
+	return pmd_offset(pud, address);
+}
+
+pte_t *pte_offset_proc(pmd_t *pmd, unsigned long address)
+{
+	return pte_offset_kernel(pmd, address);
+}
+
+pte_t *addr_pte(struct task_struct *task, unsigned long addr)
+{
+	pgd_t *pgd = pgd_offset(task->mm, addr);
+	pud_t *pud = pud_offset(pgd, addr);
+	pmd_t *pmd = pmd_offset(pud, addr);
+
+	return pte_offset_map(pmd, addr);
+}
+
+void flush_tlb_all(void)
+{
+	flush_tlb_mm(current->mm);
+}
+
+void flush_tlb_kernel_range(unsigned long start, unsigned long end)
+{
+	flush_tlb_kernel_range_common(start, end);
+}
+
+void flush_tlb_kernel_vm(void)
+{
+	flush_tlb_kernel_range_common(start_vm, end_vm);
+}
+
+void __flush_tlb_one(unsigned long addr)
+{
+	flush_tlb_kernel_range_common(addr, addr + PAGE_SIZE);
+}
+
+static void fix_range(struct mm_struct *mm, unsigned long start_addr,
+		      unsigned long end_addr, int force)
+{
+	fix_range_common(mm, start_addr, end_addr, force);
+}
+
+void flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
+		     unsigned long end)
+{
+	if (vma->vm_mm == NULL)
+		flush_tlb_kernel_range_common(start, end);
+	else fix_range(vma->vm_mm, start, end, 0);
+}
+EXPORT_SYMBOL(flush_tlb_range);
+
+void flush_tlb_mm_range(struct mm_struct *mm, unsigned long start,
+			unsigned long end)
+{
+	/*
+	 * Don't bother flushing if this address space is about to be
+	 * destroyed.
+	 */
+	if (atomic_read(&mm->mm_users) == 0)
+		return;
+
+	fix_range(mm, start, end, 0);
+}
+
+void flush_tlb_mm(struct mm_struct *mm)
+{
+	struct vm_area_struct *vma = mm->mmap;
+
+	while (vma != NULL) {
+		fix_range(mm, vma->vm_start, vma->vm_end, 0);
+		vma = vma->vm_next;
+	}
+}
+
+void force_flush_all(void)
+{
+	struct mm_struct *mm = current->mm;
+	struct vm_area_struct *vma = mm->mmap;
+
+	while (vma != NULL) {
+		fix_range(mm, vma->vm_start, vma->vm_end, 1);
+		vma = vma->vm_next;
+	}
+}