osdep: Move memalign-related functions to their own header

Move the various memalign-related functions out of osdep.h and into
their own header, which we include only where they are used.
While we're doing this, add some brief documentation comments.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20220226180723.1706285-10-peter.maydell@linaro.org

block/blkverify.c

@@ -16,6 +16,7 @@
 #include "qemu/cutils.h"
 #include "qemu/module.h"
 #include "qemu/option.h"
+#include "qemu/memalign.h"
 
 typedef struct {
     BdrvChild *test_file;

block/block-copy.c

@@ -22,6 +22,7 @@
 #include "qemu/coroutine.h"
 #include "block/aio_task.h"
 #include "qemu/error-report.h"
+#include "qemu/memalign.h"
 
 #define BLOCK_COPY_MAX_COPY_RANGE (16 * MiB)
 #define BLOCK_COPY_MAX_BUFFER (1 * MiB)

block/commit.c

@@ -20,6 +20,7 @@
 #include "qapi/error.h"
 #include "qapi/qmp/qerror.h"
 #include "qemu/ratelimit.h"
+#include "qemu/memalign.h"
 #include "sysemu/block-backend.h"
 
 enum {

block/crypto.c

@@ -31,6 +31,7 @@
 #include "qemu/module.h"
 #include "qemu/option.h"
 #include "qemu/cutils.h"
+#include "qemu/memalign.h"
 #include "crypto.h"
 
 typedef struct BlockCrypto BlockCrypto;

block/dmg.c

@@ -27,6 +27,7 @@
 #include "qemu/bswap.h"
 #include "qemu/error-report.h"
 #include "qemu/module.h"
+#include "qemu/memalign.h"
 #include "dmg.h"
 
 int (*dmg_uncompress_bz2)(char *next_in, unsigned int avail_in,

block/export/fuse.c

@@ -19,6 +19,7 @@
 #define FUSE_USE_VERSION 31
 
 #include "qemu/osdep.h"
+#include "qemu/memalign.h"
 #include "block/aio.h"
 #include "block/block.h"
 #include "block/export.h"

block/file-posix.c

@@ -31,6 +31,7 @@
 #include "qemu/module.h"
 #include "qemu/option.h"
 #include "qemu/units.h"
+#include "qemu/memalign.h"
 #include "trace.h"
 #include "block/thread-pool.h"
 #include "qemu/iov.h"

block/io.c

@@ -32,6 +32,7 @@
 #include "block/coroutines.h"
 #include "block/write-threshold.h"
 #include "qemu/cutils.h"
+#include "qemu/memalign.h"
 #include "qapi/error.h"
 #include "qemu/error-report.h"
 #include "qemu/main-loop.h"

block/mirror.c

@@ -23,6 +23,7 @@
 #include "qapi/qmp/qerror.h"
 #include "qemu/ratelimit.h"
 #include "qemu/bitmap.h"
+#include "qemu/memalign.h"
 
 #define MAX_IN_FLIGHT 16
 #define MAX_IO_BYTES (1 << 20) /* 1 Mb */

block/nvme.c

@@ -21,6 +21,7 @@
 #include "qemu/module.h"
 #include "qemu/cutils.h"
 #include "qemu/option.h"
+#include "qemu/memalign.h"
 #include "qemu/vfio-helpers.h"
 #include "block/block_int.h"
 #include "sysemu/replay.h"

block/parallels-ext.c

@@ -29,6 +29,7 @@
 #include "parallels.h"
 #include "crypto/hash.h"
 #include "qemu/uuid.h"
+#include "qemu/memalign.h"
 
 #define PARALLELS_FORMAT_EXTENSION_MAGIC 0xAB234CEF23DCEA87ULL
 

block/parallels.c

@@ -41,6 +41,7 @@
 #include "qapi/qapi-visit-block-core.h"
 #include "qemu/bswap.h"
 #include "qemu/bitmap.h"
+#include "qemu/memalign.h"
 #include "migration/blocker.h"
 #include "parallels.h"
 

block/qcow.c

@@ -32,6 +32,7 @@
 #include "qemu/option.h"
 #include "qemu/bswap.h"
 #include "qemu/cutils.h"
+#include "qemu/memalign.h"
 #include <zlib.h>
 #include "qapi/qmp/qdict.h"
 #include "qapi/qmp/qstring.h"

block/qcow2-cache.c

@@ -23,6 +23,7 @@
  */
 
 #include "qemu/osdep.h"
+#include "qemu/memalign.h"
 #include "qcow2.h"
 #include "trace.h"
 

block/qcow2-cluster.c

@@ -28,6 +28,7 @@
 #include "qapi/error.h"
 #include "qcow2.h"
 #include "qemu/bswap.h"
+#include "qemu/memalign.h"
 #include "trace.h"
 
 int qcow2_shrink_l1_table(BlockDriverState *bs, uint64_t exact_size)

block/qcow2-refcount.c

@@ -28,6 +28,7 @@
 #include "qemu/range.h"
 #include "qemu/bswap.h"
 #include "qemu/cutils.h"
+#include "qemu/memalign.h"
 #include "trace.h"
 
 static int64_t alloc_clusters_noref(BlockDriverState *bs, uint64_t size,

block/qcow2-snapshot.c

@@ -29,6 +29,7 @@
 #include "qemu/bswap.h"
 #include "qemu/error-report.h"
 #include "qemu/cutils.h"
+#include "qemu/memalign.h"
 
 static void qcow2_free_single_snapshot(BlockDriverState *bs, int i)
 {

block/qcow2.c

@@ -38,6 +38,7 @@
 #include "qemu/option_int.h"
 #include "qemu/cutils.h"
 #include "qemu/bswap.h"
+#include "qemu/memalign.h"
 #include "qapi/qobject-input-visitor.h"
 #include "qapi/qapi-visit-block-core.h"
 #include "crypto.h"

block/qed-l2-cache.c

@@ -51,6 +51,7 @@
  */
 
 #include "qemu/osdep.h"
+#include "qemu/memalign.h"
 #include "trace.h"
 #include "qed.h"
 

block/qed-table.c

@@ -17,6 +17,7 @@
 #include "qemu/sockets.h" /* for EINPROGRESS on Windows */
 #include "qed.h"
 #include "qemu/bswap.h"
+#include "qemu/memalign.h"
 
 /* Called with table_lock held.  */
 static int coroutine_fn qed_read_table(BDRVQEDState *s, uint64_t offset,

block/qed.c

@@ -20,6 +20,7 @@
 #include "qemu/main-loop.h"
 #include "qemu/module.h"
 #include "qemu/option.h"
+#include "qemu/memalign.h"
 #include "trace.h"
 #include "qed.h"
 #include "sysemu/block-backend.h"

block/quorum.c

@@ -17,6 +17,7 @@
 #include "qemu/cutils.h"
 #include "qemu/module.h"
 #include "qemu/option.h"
+#include "qemu/memalign.h"
 #include "block/block_int.h"
 #include "block/coroutines.h"
 #include "block/qdict.h"

block/raw-format.c

@@ -31,6 +31,7 @@
 #include "qapi/error.h"
 #include "qemu/module.h"
 #include "qemu/option.h"
+#include "qemu/memalign.h"
 
 typedef struct BDRVRawState {
     uint64_t offset;

block/vdi.c

@@ -64,6 +64,7 @@
 #include "qemu/coroutine.h"
 #include "qemu/cutils.h"
 #include "qemu/uuid.h"
+#include "qemu/memalign.h"
 
 /* Code configuration options. */
 

block/vhdx-log.c

@@ -23,6 +23,7 @@
 #include "block/block_int.h"
 #include "qemu/error-report.h"
 #include "qemu/bswap.h"
+#include "qemu/memalign.h"
 #include "vhdx.h"
 
 

block/vhdx.c

@@ -25,6 +25,7 @@
 #include "qemu/crc32c.h"
 #include "qemu/bswap.h"
 #include "qemu/error-report.h"
+#include "qemu/memalign.h"
 #include "vhdx.h"
 #include "migration/blocker.h"
 #include "qemu/uuid.h"

block/vmdk.c

@@ -33,6 +33,7 @@
 #include "qemu/module.h"
 #include "qemu/option.h"
 #include "qemu/bswap.h"
+#include "qemu/memalign.h"
 #include "migration/blocker.h"
 #include "qemu/cutils.h"
 #include <zlib.h>

block/vpc.c

@@ -33,6 +33,7 @@
 #include "migration/blocker.h"
 #include "qemu/bswap.h"
 #include "qemu/uuid.h"
+#include "qemu/memalign.h"
 #include "qapi/qmp/qdict.h"
 #include "qapi/qobject-input-visitor.h"
 #include "qapi/qapi-visit-block-core.h"

block/win32-aio.c

@@ -29,6 +29,7 @@
 #include "block/raw-aio.h"
 #include "qemu/event_notifier.h"
 #include "qemu/iov.h"
+#include "qemu/memalign.h"
 #include <windows.h>
 #include <winioctl.h>
 

hw/block/dataplane/xen-block.c

@@ -21,6 +21,7 @@
 #include "qemu/osdep.h"
 #include "qemu/error-report.h"
 #include "qemu/main-loop.h"
+#include "qemu/memalign.h"
 #include "qapi/error.h"
 #include "hw/xen/xen_common.h"
 #include "hw/block/xen_blkif.h"

hw/block/fdc.c

@@ -32,6 +32,7 @@
 #include "qapi/error.h"
 #include "qemu/error-report.h"
 #include "qemu/timer.h"
+#include "qemu/memalign.h"
 #include "hw/irq.h"
 #include "hw/isa/isa.h"
 #include "hw/qdev-properties.h"

hw/ide/core.c

@@ -30,6 +30,7 @@
 #include "qemu/main-loop.h"
 #include "qemu/timer.h"
 #include "qemu/hw-version.h"
+#include "qemu/memalign.h"
 #include "sysemu/sysemu.h"
 #include "sysemu/blockdev.h"
 #include "sysemu/dma.h"

hw/ppc/spapr.c

@@ -27,6 +27,7 @@
 #include "qemu/osdep.h"
 #include "qemu-common.h"
 #include "qemu/datadir.h"
+#include "qemu/memalign.h"
 #include "qapi/error.h"
 #include "qapi/qapi-events-machine.h"
 #include "qapi/qapi-events-qdev.h"

hw/ppc/spapr_softmmu.c

@@ -1,5 +1,6 @@
 #include "qemu/osdep.h"
 #include "qemu/cutils.h"
+#include "qemu/memalign.h"
 #include "cpu.h"
 #include "helper_regs.h"
 #include "hw/ppc/spapr.h"

hw/scsi/scsi-disk.c

@@ -26,6 +26,7 @@
 #include "qemu/main-loop.h"
 #include "qemu/module.h"
 #include "qemu/hw-version.h"
+#include "qemu/memalign.h"
 #include "hw/scsi/scsi.h"
 #include "migration/qemu-file-types.h"
 #include "migration/vmstate.h"

hw/tpm/tpm_ppi.c

@@ -12,7 +12,7 @@
  */
 
 #include "qemu/osdep.h"
-
+#include "qemu/memalign.h"
 #include "qapi/error.h"
 #include "sysemu/memory_mapping.h"
 #include "migration/vmstate.h"

include/qemu/memalign.h

@@ -0,0 +1,61 @@
+/*
+ * Allocation and free functions for aligned memory
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#ifndef QEMU_MEMALIGN_H
+#define QEMU_MEMALIGN_H
+
+/**
+ * qemu_try_memalign: Allocate aligned memory
+ * @alignment: required alignment, in bytes
+ * @size: size of allocation, in bytes
+ *
+ * Allocate memory on an aligned boundary (i.e. the returned
+ * address will be an exact multiple of @alignment).
+ * @alignment must be a power of 2, or the function will assert().
+ * On success, returns allocated memory; on failure, returns NULL.
+ *
+ * The memory allocated through this function must be freed via
+ * qemu_vfree() (and not via free()).
+ */
+void *qemu_try_memalign(size_t alignment, size_t size);
+/**
+ * qemu_memalign: Allocate aligned memory, without failing
+ * @alignment: required alignment, in bytes
+ * @size: size of allocation, in bytes
+ *
+ * Allocate memory in the same way as qemu_try_memalign(), but
+ * abort() with an error message if the memory allocation fails.
+ *
+ * The memory allocated through this function must be freed via
+ * qemu_vfree() (and not via free()).
+ */
+void *qemu_memalign(size_t alignment, size_t size);
+/**
+ * qemu_vfree: Free memory allocated through qemu_memalign
+ * @ptr: memory to free
+ *
+ * This function must be used to free memory allocated via qemu_memalign()
+ * or qemu_try_memalign(). (Using the wrong free function will cause
+ * subtle bugs on Windows hosts.)
+ */
+void qemu_vfree(void *ptr);
+/*
+ * It's an analog of GLIB's g_autoptr_cleanup_generic_gfree(), used to define
+ * g_autofree macro.
+ */
+static inline void qemu_cleanup_generic_vfree(void *p)
+{
+  void **pp = (void **)p;
+  qemu_vfree(*pp);
+}
+
+/*
+ * Analog of g_autofree, but qemu_vfree is called on cleanup instead of g_free.
+ */
+#define QEMU_AUTO_VFREE __attribute__((cleanup(qemu_cleanup_generic_vfree)))
+
+#endif

include/qemu/osdep.h

@@ -379,28 +379,10 @@ extern "C" {
 #endif
 
 int qemu_daemon(int nochdir, int noclose);
-void *qemu_try_memalign(size_t alignment, size_t size);
-void *qemu_memalign(size_t alignment, size_t size);
 void *qemu_anon_ram_alloc(size_t size, uint64_t *align, bool shared,
                           bool noreserve);
-void qemu_vfree(void *ptr);
 void qemu_anon_ram_free(void *ptr, size_t size);
 
-/*
- * It's an analog of GLIB's g_autoptr_cleanup_generic_gfree(), used to define
- * g_autofree macro.
- */
-static inline void qemu_cleanup_generic_vfree(void *p)
-{
-  void **pp = (void **)p;
-  qemu_vfree(*pp);
-}
-
-/*
- * Analog of g_autofree, but qemu_vfree is called on cleanup instead of g_free.
- */
-#define QEMU_AUTO_VFREE __attribute__((cleanup(qemu_cleanup_generic_vfree)))
-
 #ifdef _WIN32
 #define HAVE_CHARDEV_SERIAL 1
 #elif defined(__linux__) || defined(__sun__) || defined(__FreeBSD__)    \

nbd/server.c

@@ -25,6 +25,7 @@
 #include "trace.h"
 #include "nbd-internal.h"
 #include "qemu/units.h"
+#include "qemu/memalign.h"
 
 #define NBD_META_ID_BASE_ALLOCATION 0
 #define NBD_META_ID_ALLOCATION_DEPTH 1

net/l2tpv3.c

@@ -34,7 +34,7 @@
 #include "qemu/sockets.h"
 #include "qemu/iov.h"
 #include "qemu/main-loop.h"
-
+#include "qemu/memalign.h"
 
 /* The buffer size needs to be investigated for optimum numbers and
  * optimum means of paging in on different systems. This size is

plugins/loader.c

@@ -27,6 +27,7 @@
 #include "qemu/cacheinfo.h"
 #include "qemu/xxhash.h"
 #include "qemu/plugin.h"
+#include "qemu/memalign.h"
 #include "hw/core/cpu.h"
 #include "exec/exec-all.h"
 #ifndef CONFIG_USER_ONLY

qemu-img.c

@@ -42,6 +42,7 @@
 #include "qemu/module.h"
 #include "qemu/sockets.h"
 #include "qemu/units.h"
+#include "qemu/memalign.h"
 #include "qom/object_interfaces.h"
 #include "sysemu/block-backend.h"
 #include "block/block_int.h"

qemu-io-cmds.c

@@ -21,6 +21,7 @@
 #include "qemu/option.h"
 #include "qemu/timer.h"
 #include "qemu/cutils.h"
+#include "qemu/memalign.h"
 
 #define CMD_NOFILE_OK   0x01
 

qom/object.c

@@ -16,6 +16,7 @@
 #include "qom/object.h"
 #include "qom/object_interfaces.h"
 #include "qemu/cutils.h"
+#include "qemu/memalign.h"
 #include "qapi/visitor.h"
 #include "qapi/string-input-visitor.h"
 #include "qapi/string-output-visitor.h"

softmmu/physmem.c

@@ -42,6 +42,7 @@
 #include "qemu/config-file.h"
 #include "qemu/error-report.h"
 #include "qemu/qemu-print.h"
+#include "qemu/memalign.h"
 #include "exec/memory.h"
 #include "exec/ioport.h"
 #include "sysemu/dma.h"

target/i386/hvf/hvf.c

@@ -49,6 +49,7 @@
 #include "qemu/osdep.h"
 #include "qemu-common.h"
 #include "qemu/error-report.h"
+#include "qemu/memalign.h"
 
 #include "sysemu/hvf.h"
 #include "sysemu/hvf_int.h"

target/i386/kvm/kvm.c

@@ -37,6 +37,7 @@
 #include "qemu/main-loop.h"
 #include "qemu/config-file.h"
 #include "qemu/error-report.h"
+#include "qemu/memalign.h"
 #include "hw/i386/x86.h"
 #include "hw/i386/apic.h"
 #include "hw/i386/apic_internal.h"

tcg/region.c

@@ -26,6 +26,7 @@
 #include "qemu/units.h"
 #include "qemu/madvise.h"
 #include "qemu/mprotect.h"
+#include "qemu/memalign.h"
 #include "qemu/cacheinfo.h"
 #include "qapi/error.h"
 #include "exec/exec-all.h"

tests/bench/atomic_add-bench.c

@@ -2,6 +2,7 @@
 #include "qemu/thread.h"
 #include "qemu/host-utils.h"
 #include "qemu/processor.h"
+#include "qemu/memalign.h"
 
 struct thread_info {
     uint64_t r;

tests/bench/qht-bench.c

@@ -10,6 +10,7 @@
 #include "qemu/qht.h"
 #include "qemu/rcu.h"
 #include "qemu/xxhash.h"
+#include "qemu/memalign.h"
 
 struct thread_stats {
     size_t rd;

util/atomic64.c

@@ -8,6 +8,7 @@
 #include "qemu/atomic.h"
 #include "qemu/thread.h"
 #include "qemu/cacheinfo.h"
+#include "qemu/memalign.h"
 
 #ifdef CONFIG_ATOMIC64
 #error This file must only be compiled if !CONFIG_ATOMIC64

util/memalign.c

@@ -26,6 +26,7 @@
 
 #include "qemu/osdep.h"
 #include "qemu/host-utils.h"
+#include "qemu/memalign.h"
 #include "trace.h"
 
 void *qemu_try_memalign(size_t alignment, size_t size)

util/qht.c

@@ -69,6 +69,7 @@
 #include "qemu/qht.h"
 #include "qemu/atomic.h"
 #include "qemu/rcu.h"
+#include "qemu/memalign.h"
 
 //#define QHT_DEBUG