Introduce Virtio-loopback epsilon release:

Epsilon release introduces a new compatibility layer which make virtio-loopback
design to work with QEMU and rust-vmm vhost-user backend without require any
changes.

Signed-off-by: Timos Ampelikiotis <t.ampelikiotis@virtualopensystems.com>
Change-Id: I52e57563e08a7d0bdc002f8e928ee61ba0c53dd9

1 files changed, 523 insertions, 0 deletions

diff --git a/include/exec/ram_addr.h b/include/exec/ram_addr.h
new file mode 100644
index 000000000..64fb936c7
--- /dev/null
+++ b/include/exec/ram_addr.h
@@ -0,0 +1,523 @@
+/*
+ * Declarations for cpu physical memory functions
+ *
+ * Copyright 2011 Red Hat, Inc. and/or its affiliates
+ *
+ * Authors:
+ *  Avi Kivity <avi@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or
+ * later.  See the COPYING file in the top-level directory.
+ *
+ */
+
+/*
+ * This header is for use by exec.c and memory.c ONLY.  Do not include it.
+ * The functions declared here will be removed soon.
+ */
+
+#ifndef RAM_ADDR_H
+#define RAM_ADDR_H
+
+#ifndef CONFIG_USER_ONLY
+#include "cpu.h"
+#include "sysemu/xen.h"
+#include "sysemu/tcg.h"
+#include "exec/ramlist.h"
+#include "exec/ramblock.h"
+
+extern uint64_t total_dirty_pages;
+
+/**
+ * clear_bmap_size: calculate clear bitmap size
+ *
+ * @pages: number of guest pages
+ * @shift: guest page number shift
+ *
+ * Returns: number of bits for the clear bitmap
+ */
+static inline long clear_bmap_size(uint64_t pages, uint8_t shift)
+{
+    return DIV_ROUND_UP(pages, 1UL << shift);
+}
+
+/**
+ * clear_bmap_set: set clear bitmap for the page range
+ *
+ * @rb: the ramblock to operate on
+ * @start: the start page number
+ * @size: number of pages to set in the bitmap
+ *
+ * Returns: None
+ */
+static inline void clear_bmap_set(RAMBlock *rb, uint64_t start,
+                                  uint64_t npages)
+{
+    uint8_t shift = rb->clear_bmap_shift;
+
+    bitmap_set_atomic(rb->clear_bmap, start >> shift,
+                      clear_bmap_size(npages, shift));
+}
+
+/**
+ * clear_bmap_test_and_clear: test clear bitmap for the page, clear if set
+ *
+ * @rb: the ramblock to operate on
+ * @page: the page number to check
+ *
+ * Returns: true if the bit was set, false otherwise
+ */
+static inline bool clear_bmap_test_and_clear(RAMBlock *rb, uint64_t page)
+{
+    uint8_t shift = rb->clear_bmap_shift;
+
+    return bitmap_test_and_clear_atomic(rb->clear_bmap, page >> shift, 1);
+}
+
+static inline bool offset_in_ramblock(RAMBlock *b, ram_addr_t offset)
+{
+    return (b && b->host && offset < b->used_length) ? true : false;
+}
+
+static inline void *ramblock_ptr(RAMBlock *block, ram_addr_t offset)
+{
+    assert(offset_in_ramblock(block, offset));
+    return (char *)block->host + offset;
+}
+
+static inline unsigned long int ramblock_recv_bitmap_offset(void *host_addr,
+                                                            RAMBlock *rb)
+{
+    uint64_t host_addr_offset =
+            (uint64_t)(uintptr_t)(host_addr - (void *)rb->host);
+    return host_addr_offset >> TARGET_PAGE_BITS;
+}
+
+bool ramblock_is_pmem(RAMBlock *rb);
+
+long qemu_minrampagesize(void);
+long qemu_maxrampagesize(void);
+
+/**
+ * qemu_ram_alloc_from_file,
+ * qemu_ram_alloc_from_fd:  Allocate a ram block from the specified backing
+ *                          file or device
+ *
+ * Parameters:
+ *  @size: the size in bytes of the ram block
+ *  @mr: the memory region where the ram block is
+ *  @ram_flags: RamBlock flags. Supported flags: RAM_SHARED, RAM_PMEM,
+ *              RAM_NORESERVE.
+ *  @mem_path or @fd: specify the backing file or device
+ *  @readonly: true to open @path for reading, false for read/write.
+ *  @errp: pointer to Error*, to store an error if it happens
+ *
+ * Return:
+ *  On success, return a pointer to the ram block.
+ *  On failure, return NULL.
+ */
+RAMBlock *qemu_ram_alloc_from_file(ram_addr_t size, MemoryRegion *mr,
+                                   uint32_t ram_flags, const char *mem_path,
+                                   bool readonly, Error **errp);
+RAMBlock *qemu_ram_alloc_from_fd(ram_addr_t size, MemoryRegion *mr,
+                                 uint32_t ram_flags, int fd, off_t offset,
+                                 bool readonly, Error **errp);
+
+RAMBlock *qemu_ram_alloc_from_ptr(ram_addr_t size, void *host,
+                                  MemoryRegion *mr, Error **errp);
+RAMBlock *qemu_ram_alloc(ram_addr_t size, uint32_t ram_flags, MemoryRegion *mr,
+                         Error **errp);
+RAMBlock *qemu_ram_alloc_resizeable(ram_addr_t size, ram_addr_t max_size,
+                                    void (*resized)(const char*,
+                                                    uint64_t length,
+                                                    void *host),
+                                    MemoryRegion *mr, Error **errp);
+void qemu_ram_free(RAMBlock *block);
+
+int qemu_ram_resize(RAMBlock *block, ram_addr_t newsize, Error **errp);
+
+void qemu_ram_msync(RAMBlock *block, ram_addr_t start, ram_addr_t length);
+
+/* Clear whole block of mem */
+static inline void qemu_ram_block_writeback(RAMBlock *block)
+{
+    qemu_ram_msync(block, 0, block->used_length);
+}
+
+#define DIRTY_CLIENTS_ALL     ((1 << DIRTY_MEMORY_NUM) - 1)
+#define DIRTY_CLIENTS_NOCODE  (DIRTY_CLIENTS_ALL & ~(1 << DIRTY_MEMORY_CODE))
+
+void tb_invalidate_phys_range(ram_addr_t start, ram_addr_t end);
+
+static inline bool cpu_physical_memory_get_dirty(ram_addr_t start,
+                                                 ram_addr_t length,
+                                                 unsigned client)
+{
+    DirtyMemoryBlocks *blocks;
+    unsigned long end, page;
+    unsigned long idx, offset, base;
+    bool dirty = false;
+
+    assert(client < DIRTY_MEMORY_NUM);
+
+    end = TARGET_PAGE_ALIGN(start + length) >> TARGET_PAGE_BITS;
+    page = start >> TARGET_PAGE_BITS;
+
+    WITH_RCU_READ_LOCK_GUARD() {
+        blocks = qatomic_rcu_read(&ram_list.dirty_memory[client]);
+
+        idx = page / DIRTY_MEMORY_BLOCK_SIZE;
+        offset = page % DIRTY_MEMORY_BLOCK_SIZE;
+        base = page - offset;
+        while (page < end) {
+            unsigned long next = MIN(end, base + DIRTY_MEMORY_BLOCK_SIZE);
+            unsigned long num = next - base;
+            unsigned long found = find_next_bit(blocks->blocks[idx],
+                                                num, offset);
+            if (found < num) {
+                dirty = true;
+                break;
+            }
+
+            page = next;
+            idx++;
+            offset = 0;
+            base += DIRTY_MEMORY_BLOCK_SIZE;
+        }
+    }
+
+    return dirty;
+}
+
+static inline bool cpu_physical_memory_all_dirty(ram_addr_t start,
+                                                 ram_addr_t length,
+                                                 unsigned client)
+{
+    DirtyMemoryBlocks *blocks;
+    unsigned long end, page;
+    unsigned long idx, offset, base;
+    bool dirty = true;
+
+    assert(client < DIRTY_MEMORY_NUM);
+
+    end = TARGET_PAGE_ALIGN(start + length) >> TARGET_PAGE_BITS;
+    page = start >> TARGET_PAGE_BITS;
+
+    RCU_READ_LOCK_GUARD();
+
+    blocks = qatomic_rcu_read(&ram_list.dirty_memory[client]);
+
+    idx = page / DIRTY_MEMORY_BLOCK_SIZE;
+    offset = page % DIRTY_MEMORY_BLOCK_SIZE;
+    base = page - offset;
+    while (page < end) {
+        unsigned long next = MIN(end, base + DIRTY_MEMORY_BLOCK_SIZE);
+        unsigned long num = next - base;
+        unsigned long found = find_next_zero_bit(blocks->blocks[idx], num, offset);
+        if (found < num) {
+            dirty = false;
+            break;
+        }
+
+        page = next;
+        idx++;
+        offset = 0;
+        base += DIRTY_MEMORY_BLOCK_SIZE;
+    }
+
+    return dirty;
+}
+
+static inline bool cpu_physical_memory_get_dirty_flag(ram_addr_t addr,
+                                                      unsigned client)
+{
+    return cpu_physical_memory_get_dirty(addr, 1, client);
+}
+
+static inline bool cpu_physical_memory_is_clean(ram_addr_t addr)
+{
+    bool vga = cpu_physical_memory_get_dirty_flag(addr, DIRTY_MEMORY_VGA);
+    bool code = cpu_physical_memory_get_dirty_flag(addr, DIRTY_MEMORY_CODE);
+    bool migration =
+        cpu_physical_memory_get_dirty_flag(addr, DIRTY_MEMORY_MIGRATION);
+    return !(vga && code && migration);
+}
+
+static inline uint8_t cpu_physical_memory_range_includes_clean(ram_addr_t start,
+                                                               ram_addr_t length,
+                                                               uint8_t mask)
+{
+    uint8_t ret = 0;
+
+    if (mask & (1 << DIRTY_MEMORY_VGA) &&
+        !cpu_physical_memory_all_dirty(start, length, DIRTY_MEMORY_VGA)) {
+        ret |= (1 << DIRTY_MEMORY_VGA);
+    }
+    if (mask & (1 << DIRTY_MEMORY_CODE) &&
+        !cpu_physical_memory_all_dirty(start, length, DIRTY_MEMORY_CODE)) {
+        ret |= (1 << DIRTY_MEMORY_CODE);
+    }
+    if (mask & (1 << DIRTY_MEMORY_MIGRATION) &&
+        !cpu_physical_memory_all_dirty(start, length, DIRTY_MEMORY_MIGRATION)) {
+        ret |= (1 << DIRTY_MEMORY_MIGRATION);
+    }
+    return ret;
+}
+
+static inline void cpu_physical_memory_set_dirty_flag(ram_addr_t addr,
+                                                      unsigned client)
+{
+    unsigned long page, idx, offset;
+    DirtyMemoryBlocks *blocks;
+
+    assert(client < DIRTY_MEMORY_NUM);
+
+    page = addr >> TARGET_PAGE_BITS;
+    idx = page / DIRTY_MEMORY_BLOCK_SIZE;
+    offset = page % DIRTY_MEMORY_BLOCK_SIZE;
+
+    RCU_READ_LOCK_GUARD();
+
+    blocks = qatomic_rcu_read(&ram_list.dirty_memory[client]);
+
+    set_bit_atomic(offset, blocks->blocks[idx]);
+}
+
+static inline void cpu_physical_memory_set_dirty_range(ram_addr_t start,
+                                                       ram_addr_t length,
+                                                       uint8_t mask)
+{
+    DirtyMemoryBlocks *blocks[DIRTY_MEMORY_NUM];
+    unsigned long end, page;
+    unsigned long idx, offset, base;
+    int i;
+
+    if (!mask && !xen_enabled()) {
+        return;
+    }
+
+    end = TARGET_PAGE_ALIGN(start + length) >> TARGET_PAGE_BITS;
+    page = start >> TARGET_PAGE_BITS;
+
+    WITH_RCU_READ_LOCK_GUARD() {
+        for (i = 0; i < DIRTY_MEMORY_NUM; i++) {
+            blocks[i] = qatomic_rcu_read(&ram_list.dirty_memory[i]);
+        }
+
+        idx = page / DIRTY_MEMORY_BLOCK_SIZE;
+        offset = page % DIRTY_MEMORY_BLOCK_SIZE;
+        base = page - offset;
+        while (page < end) {
+            unsigned long next = MIN(end, base + DIRTY_MEMORY_BLOCK_SIZE);
+
+            if (likely(mask & (1 << DIRTY_MEMORY_MIGRATION))) {
+                bitmap_set_atomic(blocks[DIRTY_MEMORY_MIGRATION]->blocks[idx],
+                                  offset, next - page);
+            }
+            if (unlikely(mask & (1 << DIRTY_MEMORY_VGA))) {
+                bitmap_set_atomic(blocks[DIRTY_MEMORY_VGA]->blocks[idx],
+                                  offset, next - page);
+            }
+            if (unlikely(mask & (1 << DIRTY_MEMORY_CODE))) {
+                bitmap_set_atomic(blocks[DIRTY_MEMORY_CODE]->blocks[idx],
+                                  offset, next - page);
+            }
+
+            page = next;
+            idx++;
+            offset = 0;
+            base += DIRTY_MEMORY_BLOCK_SIZE;
+        }
+    }
+
+    xen_hvm_modified_memory(start, length);
+}
+
+#if !defined(_WIN32)
+static inline void cpu_physical_memory_set_dirty_lebitmap(unsigned long *bitmap,
+                                                          ram_addr_t start,
+                                                          ram_addr_t pages)
+{
+    unsigned long i, j;
+    unsigned long page_number, c;
+    hwaddr addr;
+    ram_addr_t ram_addr;
+    unsigned long len = (pages + HOST_LONG_BITS - 1) / HOST_LONG_BITS;
+    unsigned long hpratio = qemu_real_host_page_size / TARGET_PAGE_SIZE;
+    unsigned long page = BIT_WORD(start >> TARGET_PAGE_BITS);
+
+    /* start address is aligned at the start of a word? */
+    if ((((page * BITS_PER_LONG) << TARGET_PAGE_BITS) == start) &&
+        (hpratio == 1)) {
+        unsigned long **blocks[DIRTY_MEMORY_NUM];
+        unsigned long idx;
+        unsigned long offset;
+        long k;
+        long nr = BITS_TO_LONGS(pages);
+
+        idx = (start >> TARGET_PAGE_BITS) / DIRTY_MEMORY_BLOCK_SIZE;
+        offset = BIT_WORD((start >> TARGET_PAGE_BITS) %
+                          DIRTY_MEMORY_BLOCK_SIZE);
+
+        WITH_RCU_READ_LOCK_GUARD() {
+            for (i = 0; i < DIRTY_MEMORY_NUM; i++) {
+                blocks[i] =
+                    qatomic_rcu_read(&ram_list.dirty_memory[i])->blocks;
+            }
+
+            for (k = 0; k < nr; k++) {
+                if (bitmap[k]) {
+                    unsigned long temp = leul_to_cpu(bitmap[k]);
+
+                    qatomic_or(&blocks[DIRTY_MEMORY_VGA][idx][offset], temp);
+
+                    if (global_dirty_tracking) {
+                        qatomic_or(
+                                &blocks[DIRTY_MEMORY_MIGRATION][idx][offset],
+                                temp);
+                        if (unlikely(
+                            global_dirty_tracking & GLOBAL_DIRTY_DIRTY_RATE)) {
+                            total_dirty_pages += ctpopl(temp);
+                        }
+                    }
+
+                    if (tcg_enabled()) {
+                        qatomic_or(&blocks[DIRTY_MEMORY_CODE][idx][offset],
+                                   temp);
+                    }
+                }
+
+                if (++offset >= BITS_TO_LONGS(DIRTY_MEMORY_BLOCK_SIZE)) {
+                    offset = 0;
+                    idx++;
+                }
+            }
+        }
+
+        xen_hvm_modified_memory(start, pages << TARGET_PAGE_BITS);
+    } else {
+        uint8_t clients = tcg_enabled() ? DIRTY_CLIENTS_ALL : DIRTY_CLIENTS_NOCODE;
+
+        if (!global_dirty_tracking) {
+            clients &= ~(1 << DIRTY_MEMORY_MIGRATION);
+        }
+
+        /*
+         * bitmap-traveling is faster than memory-traveling (for addr...)
+         * especially when most of the memory is not dirty.
+         */
+        for (i = 0; i < len; i++) {
+            if (bitmap[i] != 0) {
+                c = leul_to_cpu(bitmap[i]);
+                if (unlikely(global_dirty_tracking & GLOBAL_DIRTY_DIRTY_RATE)) {
+                    total_dirty_pages += ctpopl(c);
+                }
+                do {
+                    j = ctzl(c);
+                    c &= ~(1ul << j);
+                    page_number = (i * HOST_LONG_BITS + j) * hpratio;
+                    addr = page_number * TARGET_PAGE_SIZE;
+                    ram_addr = start + addr;
+                    cpu_physical_memory_set_dirty_range(ram_addr,
+                                       TARGET_PAGE_SIZE * hpratio, clients);
+                } while (c != 0);
+            }
+        }
+    }
+}
+#endif /* not _WIN32 */
+
+bool cpu_physical_memory_test_and_clear_dirty(ram_addr_t start,
+                                              ram_addr_t length,
+                                              unsigned client);
+
+DirtyBitmapSnapshot *cpu_physical_memory_snapshot_and_clear_dirty
+    (MemoryRegion *mr, hwaddr offset, hwaddr length, unsigned client);
+
+bool cpu_physical_memory_snapshot_get_dirty(DirtyBitmapSnapshot *snap,
+                                            ram_addr_t start,
+                                            ram_addr_t length);
+
+static inline void cpu_physical_memory_clear_dirty_range(ram_addr_t start,
+                                                         ram_addr_t length)
+{
+    cpu_physical_memory_test_and_clear_dirty(start, length, DIRTY_MEMORY_MIGRATION);
+    cpu_physical_memory_test_and_clear_dirty(start, length, DIRTY_MEMORY_VGA);
+    cpu_physical_memory_test_and_clear_dirty(start, length, DIRTY_MEMORY_CODE);
+}
+
+
+/* Called with RCU critical section */
+static inline
+uint64_t cpu_physical_memory_sync_dirty_bitmap(RAMBlock *rb,
+                                               ram_addr_t start,
+                                               ram_addr_t length)
+{
+    ram_addr_t addr;
+    unsigned long word = BIT_WORD((start + rb->offset) >> TARGET_PAGE_BITS);
+    uint64_t num_dirty = 0;
+    unsigned long *dest = rb->bmap;
+
+    /* start address and length is aligned at the start of a word? */
+    if (((word * BITS_PER_LONG) << TARGET_PAGE_BITS) ==
+         (start + rb->offset) &&
+        !(length & ((BITS_PER_LONG << TARGET_PAGE_BITS) - 1))) {
+        int k;
+        int nr = BITS_TO_LONGS(length >> TARGET_PAGE_BITS);
+        unsigned long * const *src;
+        unsigned long idx = (word * BITS_PER_LONG) / DIRTY_MEMORY_BLOCK_SIZE;
+        unsigned long offset = BIT_WORD((word * BITS_PER_LONG) %
+                                        DIRTY_MEMORY_BLOCK_SIZE);
+        unsigned long page = BIT_WORD(start >> TARGET_PAGE_BITS);
+
+        src = qatomic_rcu_read(
+                &ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION])->blocks;
+
+        for (k = page; k < page + nr; k++) {
+            if (src[idx][offset]) {
+                unsigned long bits = qatomic_xchg(&src[idx][offset], 0);
+                unsigned long new_dirty;
+                new_dirty = ~dest[k];
+                dest[k] |= bits;
+                new_dirty &= bits;
+                num_dirty += ctpopl(new_dirty);
+            }
+
+            if (++offset >= BITS_TO_LONGS(DIRTY_MEMORY_BLOCK_SIZE)) {
+                offset = 0;
+                idx++;
+            }
+        }
+
+        if (rb->clear_bmap) {
+            /*
+             * Postpone the dirty bitmap clear to the point before we
+             * really send the pages, also we will split the clear
+             * dirty procedure into smaller chunks.
+             */
+            clear_bmap_set(rb, start >> TARGET_PAGE_BITS,
+                           length >> TARGET_PAGE_BITS);
+        } else {
+            /* Slow path - still do that in a huge chunk */
+            memory_region_clear_dirty_bitmap(rb->mr, start, length);
+        }
+    } else {
+        ram_addr_t offset = rb->offset;
+
+        for (addr = 0; addr < length; addr += TARGET_PAGE_SIZE) {
+            if (cpu_physical_memory_test_and_clear_dirty(
+                        start + addr + offset,
+                        TARGET_PAGE_SIZE,
+                        DIRTY_MEMORY_MIGRATION)) {
+                long k = (start + addr) >> TARGET_PAGE_BITS;
+                if (!test_and_set_bit(k, dest)) {
+                    num_dirty++;
+                }
+            }
+        }
+    }
+
+    return num_dirty;
+}
+#endif
+#endif