diff --git a/block/qed.c b/block/qed.c
index eddae92..b69374b 100644
--- a/block/qed.c
+++ b/block/qed.c
@@ -567,7 +567,7 @@ static void bdrv_qed_close(BlockDriverState *bs)
 static int qed_create(const char *filename, uint32_t cluster_size,
                       uint64_t image_size, uint32_t table_size,
                       const char *backing_file, const char *backing_fmt,
-                      Error **errp)
+                      QemuOpts *opts, Error **errp)
 {
     QEDHeader header = {
         .magic = QED_MAGIC,
@@ -586,7 +586,7 @@ static int qed_create(const char *filename, uint32_t cluster_size,
     int ret = 0;
     BlockDriverState *bs;
 
-    ret = bdrv_create_file(filename, NULL, &local_err);
+    ret = bdrv_create_file(filename, opts, &local_err);
     if (ret < 0) {
         error_propagate(errp, local_err);
         return ret;
@@ -682,7 +682,7 @@ static int bdrv_qed_create(const char *filename, QemuOpts *opts, Error **errp)
     }
 
     ret = qed_create(filename, cluster_size, image_size, table_size,
-                     backing_file, backing_fmt, errp);
+                     backing_file, backing_fmt, opts, errp);
 
 finish:
     g_free(backing_file);
diff --git a/block/raw-posix.c b/block/raw-posix.c
index dacf4fb..825a0c8 100644
--- a/block/raw-posix.c
+++ b/block/raw-posix.c
@@ -55,6 +55,9 @@
 #include <linux/cdrom.h>
 #include <linux/fd.h>
 #include <linux/fs.h>
+#ifndef FS_NOCOW_FL
+#define FS_NOCOW_FL                     0x00800000 /* Do not cow file */
+#endif
 #endif
 #ifdef CONFIG_FIEMAP
 #include <linux/fiemap.h>
@@ -1278,12 +1281,14 @@ static int raw_create(const char *filename, QemuOpts *opts, Error **errp)
     int fd;
     int result = 0;
     int64_t total_size = 0;
+    bool nocow = false;
 
     strstart(filename, "file:", &filename);
 
     /* Read out options */
     total_size =
         qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0) / BDRV_SECTOR_SIZE;
+    nocow = qemu_opt_get_bool(opts, BLOCK_OPT_NOCOW, false);
 
     fd = qemu_open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY,
                    0644);
@@ -1291,6 +1296,21 @@ static int raw_create(const char *filename, QemuOpts *opts, Error **errp)
         result = -errno;
         error_setg_errno(errp, -result, "Could not create file");
     } else {
+        if (nocow) {
+#ifdef __linux__
+            /* Set NOCOW flag to solve performance issue on fs like btrfs.
+             * This is an optimisation. The FS_IOC_SETFLAGS ioctl return value
+             * will be ignored since any failure of this operation should not
+             * block the left work.
+             */
+            int attr;
+            if (ioctl(fd, FS_IOC_GETFLAGS, &attr) == 0) {
+                attr |= FS_NOCOW_FL;
+                ioctl(fd, FS_IOC_SETFLAGS, &attr);
+            }
+#endif
+        }
+
         if (ftruncate(fd, total_size * BDRV_SECTOR_SIZE) != 0) {
             result = -errno;
             error_setg_errno(errp, -result, "Could not resize file");
@@ -1477,6 +1497,11 @@ static QemuOptsList raw_create_opts = {
             .type = QEMU_OPT_SIZE,
             .help = "Virtual disk size"
         },
+        {
+            .name = BLOCK_OPT_NOCOW,
+            .type = QEMU_OPT_BOOL,
+            .help = "Turn off copy-on-write (valid only on btrfs)"
+        },
         { /* end of list */ }
     }
 };
diff --git a/block/vdi.c b/block/vdi.c
index 01fe22e..197bd77 100644
--- a/block/vdi.c
+++ b/block/vdi.c
@@ -53,6 +53,13 @@
 #include "block/block_int.h"
 #include "qemu/module.h"
 #include "migration/migration.h"
+#ifdef __linux__
+#include <linux/fs.h>
+#include <sys/ioctl.h>
+#ifndef FS_NOCOW_FL
+#define FS_NOCOW_FL                     0x00800000 /* Do not cow file */
+#endif
+#endif
 
 #if defined(CONFIG_UUID)
 #include <uuid/uuid.h>
@@ -683,6 +690,7 @@ static int vdi_create(const char *filename, QemuOpts *opts, Error **errp)
     VdiHeader header;
     size_t i;
     size_t bmap_size;
+    bool nocow = false;
 
     logout("\n");
 
@@ -699,6 +707,7 @@ static int vdi_create(const char *filename, QemuOpts *opts, Error **errp)
         image_type = VDI_TYPE_STATIC;
     }
 #endif
+    nocow = qemu_opt_get_bool_del(opts, BLOCK_OPT_NOCOW, false);
 
     if (bytes > VDI_DISK_SIZE_MAX) {
         result = -ENOTSUP;
@@ -716,6 +725,21 @@ static int vdi_create(const char *filename, QemuOpts *opts, Error **errp)
         goto exit;
     }
 
+    if (nocow) {
+#ifdef __linux__
+        /* Set NOCOW flag to solve performance issue on fs like btrfs.
+         * This is an optimisation. The FS_IOC_SETFLAGS ioctl return value will
+         * be ignored since any failure of this operation should not block the
+         * left work.
+         */
+        int attr;
+        if (ioctl(fd, FS_IOC_GETFLAGS, &attr) == 0) {
+            attr |= FS_NOCOW_FL;
+            ioctl(fd, FS_IOC_SETFLAGS, &attr);
+        }
+#endif
+    }
+
     /* We need enough blocks to store the given disk size,
        so always round up. */
     blocks = (bytes + block_size - 1) / block_size;
@@ -818,6 +842,11 @@ static QemuOptsList vdi_create_opts = {
             .def_value_str = "off"
         },
 #endif
+        {
+            .name = BLOCK_OPT_NOCOW,
+            .type = QEMU_OPT_BOOL,
+            .help = "Turn off copy-on-write (valid only on btrfs)"
+        },
         /* TODO: An additional option to set UUID values might be useful. */
         { /* end of list */ }
     }
diff --git a/block/vmdk.c b/block/vmdk.c
index d0de019..27a78da 100644
--- a/block/vmdk.c
+++ b/block/vmdk.c
@@ -1529,7 +1529,7 @@ static int coroutine_fn vmdk_co_write_zeroes(BlockDriverState *bs,
 
 static int vmdk_create_extent(const char *filename, int64_t filesize,
                               bool flat, bool compress, bool zeroed_grain,
-                              Error **errp)
+                              QemuOpts *opts, Error **errp)
 {
     int ret, i;
     BlockDriverState *bs = NULL;
@@ -1539,7 +1539,7 @@ static int vmdk_create_extent(const char *filename, int64_t filesize,
     uint32_t *gd_buf = NULL;
     int gd_buf_size;
 
-    ret = bdrv_create_file(filename, NULL, &local_err);
+    ret = bdrv_create_file(filename, opts, &local_err);
     if (ret < 0) {
         error_propagate(errp, local_err);
         goto exit;
@@ -1845,7 +1845,7 @@ static int vmdk_create(const char *filename, QemuOpts *opts, Error **errp)
                 path, desc_filename);
 
         if (vmdk_create_extent(ext_filename, size,
-                               flat, compress, zeroed_grain, errp)) {
+                               flat, compress, zeroed_grain, opts, errp)) {
             ret = -EINVAL;
             goto exit;
         }
diff --git a/block/vpc.c b/block/vpc.c
index 798d854..8b376a4 100644
--- a/block/vpc.c
+++ b/block/vpc.c
@@ -29,6 +29,13 @@
 #if defined(CONFIG_UUID)
 #include <uuid/uuid.h>
 #endif
+#ifdef __linux__
+#include <linux/fs.h>
+#include <sys/ioctl.h>
+#ifndef FS_NOCOW_FL
+#define FS_NOCOW_FL                     0x00800000 /* Do not cow file */
+#endif
+#endif
 
 /**************************************************************/
 
@@ -751,6 +758,7 @@ static int vpc_create(const char *filename, QemuOpts *opts, Error **errp)
     int64_t total_size;
     int disk_type;
     int ret = -EIO;
+    bool nocow = false;
 
     /* Read out options */
     total_size = qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0);
@@ -767,6 +775,7 @@ static int vpc_create(const char *filename, QemuOpts *opts, Error **errp)
     } else {
         disk_type = VHD_DYNAMIC;
     }
+    nocow = qemu_opt_get_bool_del(opts, BLOCK_OPT_NOCOW, false);
 
     /* Create the file */
     fd = qemu_open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, 0644);
@@ -775,6 +784,21 @@ static int vpc_create(const char *filename, QemuOpts *opts, Error **errp)
         goto out;
     }
 
+    if (nocow) {
+#ifdef __linux__
+        /* Set NOCOW flag to solve performance issue on fs like btrfs.
+         * This is an optimisation. The FS_IOC_SETFLAGS ioctl return value will
+         * be ignored since any failure of this operation should not block the
+         * left work.
+         */
+        int attr;
+        if (ioctl(fd, FS_IOC_GETFLAGS, &attr) == 0) {
+            attr |= FS_NOCOW_FL;
+            ioctl(fd, FS_IOC_SETFLAGS, &attr);
+        }
+#endif
+    }
+
     /*
      * Calculate matching total_size and geometry. Increase the number of
      * sectors requested until we get enough (or fail). This ensures that
@@ -884,6 +908,11 @@ static QemuOptsList vpc_create_opts = {
                 "Type of virtual hard disk format. Supported formats are "
                 "{dynamic (default) | fixed} "
         },
+        {
+            .name = BLOCK_OPT_NOCOW,
+            .type = QEMU_OPT_BOOL,
+            .help = "Turn off copy-on-write (valid only on btrfs)"
+        },
         { /* end of list */ }
     }
 };
diff --git a/include/block/block_int.h b/include/block/block_int.h
index 53e77cf..eaf6e31 100644
--- a/include/block/block_int.h
+++ b/include/block/block_int.h
@@ -54,6 +54,7 @@
 #define BLOCK_OPT_LAZY_REFCOUNTS    "lazy_refcounts"
 #define BLOCK_OPT_ADAPTER_TYPE      "adapter_type"
 #define BLOCK_OPT_REDUNDANCY        "redundancy"
+#define BLOCK_OPT_NOCOW             "nocow"
 
 typedef struct BdrvTrackedRequest {
     BlockDriverState *bs;
diff --git a/qemu-doc.texi b/qemu-doc.texi
index 88ec9bb..ad92c85 100644
--- a/qemu-doc.texi
+++ b/qemu-doc.texi
@@ -589,6 +589,22 @@ check -r all} is required, which may take some time.
 
 This option can only be enabled if @code{compat=1.1} is specified.
 
+@item nocow
+If this option is set to @code{on}, it will trun off COW of the file. It's only
+valid on btrfs, no effect on other file systems.
+
+Btrfs has low performance when hosting a VM image file, even more when the guest
+on the VM also using btrfs as file system. Turning off COW is a way to mitigate
+this bad performance. Generally there are two ways to turn off COW on btrfs:
+a) Disable it by mounting with nodatacow, then all newly created files will be
+NOCOW. b) For an empty file, add the NOCOW file attribute. That's what this option
+does.
+
+Note: this option is only valid to new or empty files. If there is an existing
+file which is COW and has data blocks already, it couldn't be changed to NOCOW
+by setting @code{nocow=on}. One can issue @code{lsattr filename} to check if
+the NOCOW flag is set or not (Capitabl 'C' is NOCOW flag).
+
 @end table
 
 @item qed
diff --git a/qemu-img.texi b/qemu-img.texi
index c68b541..8496f3b 100644
--- a/qemu-img.texi
+++ b/qemu-img.texi
@@ -474,6 +474,22 @@ check -r all} is required, which may take some time.
 
 This option can only be enabled if @code{compat=1.1} is specified.
 
+@item nocow
+If this option is set to @code{on}, it will trun off COW of the file. It's only
+valid on btrfs, no effect on other file systems.
+
+Btrfs has low performance when hosting a VM image file, even more when the guest
+on the VM also using btrfs as file system. Turning off COW is a way to mitigate
+this bad performance. Generally there are two ways to turn off COW on btrfs:
+a) Disable it by mounting with nodatacow, then all newly created files will be
+NOCOW. b) For an empty file, add the NOCOW file attribute. That's what this option
+does.
+
+Note: this option is only valid to new or empty files. If there is an existing
+file which is COW and has data blocks already, it couldn't be changed to NOCOW
+by setting @code{nocow=on}. One can issue @code{lsattr filename} to check if
+the NOCOW flag is set or not (Capitabl 'C' is NOCOW flag).
+
 @end table
 
 @item Other
