[v2,for-2.10,06/16] block/file-posix: Extract raw_regular_truncate()
diff mbox

Message ID 20170403160936.28293-7-mreitz@redhat.com
State New
Headers show

Commit Message

Max Reitz April 3, 2017, 4:09 p.m. UTC
This functionality is part of raw_create() which we will be able to
reuse nicely in raw_truncate().

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 block/file-posix.c | 144 +++++++++++++++++++++++++++++------------------------
 1 file changed, 78 insertions(+), 66 deletions(-)

Comments

Philippe Mathieu-Daudé April 3, 2017, 7:02 p.m. UTC | #1
On 04/03/2017 01:09 PM, Max Reitz wrote:
> This functionality is part of raw_create() which we will be able to
> reuse nicely in raw_truncate().
>
> Signed-off-by: Max Reitz <mreitz@redhat.com>
> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>

> ---
>  block/file-posix.c | 144 +++++++++++++++++++++++++++++------------------------
>  1 file changed, 78 insertions(+), 66 deletions(-)
>
> diff --git a/block/file-posix.c b/block/file-posix.c
> index cab77db963..e6b6fa30ce 100644
> --- a/block/file-posix.c
> +++ b/block/file-posix.c
> @@ -1407,6 +1407,81 @@ static void raw_close(BlockDriverState *bs)
>      }
>  }
>
> +static int raw_regular_truncate(int fd, int64_t offset, PreallocMode prealloc,
> +                                Error **errp)
> +{
> +    int result = 0;
> +    char *buf;
> +
> +    switch (prealloc) {
> +#ifdef CONFIG_POSIX_FALLOCATE
> +    case PREALLOC_MODE_FALLOC:
> +        /*
> +         * Truncating before posix_fallocate() makes it about twice slower on
> +         * file systems that do not support fallocate(), trying to check if a
> +         * block is allocated before allocating it, so don't do that here.
> +         */
> +        result = -posix_fallocate(fd, 0, offset);
> +        if (result != 0) {
> +            /* posix_fallocate() doesn't set errno. */
> +            error_setg_errno(errp, -result,
> +                             "Could not preallocate data for the new file");
> +        }
> +        return result;
> +#endif
> +    case PREALLOC_MODE_FULL:
> +    {
> +        int64_t num = 0, left = offset;
> +
> +        /*
> +         * Knowing the final size from the beginning could allow the file
> +         * system driver to do less allocations and possibly avoid
> +         * fragmentation of the file.
> +         */
> +        if (ftruncate(fd, offset) != 0) {
> +            result = -errno;
> +            error_setg_errno(errp, -result, "Could not resize file");
> +            return result;
> +        }
> +
> +        buf = g_malloc0(65536);
> +
> +        while (left > 0) {
> +            num = MIN(left, 65536);
> +            result = write(fd, buf, num);
> +            if (result < 0) {
> +                result = -errno;
> +                error_setg_errno(errp, -result,
> +                                 "Could not write to the new file");
> +                break;
> +            }
> +            left -= result;
> +        }
> +        if (result >= 0) {
> +            result = fsync(fd);
> +            if (result < 0) {
> +                result = -errno;
> +                error_setg_errno(errp, -result,
> +                                 "Could not flush new file to disk");
> +            }
> +        }
> +        g_free(buf);
> +        return result;
> +    }
> +    case PREALLOC_MODE_OFF:
> +        if (ftruncate(fd, offset) != 0) {
> +            result = -errno;
> +            error_setg_errno(errp, -result, "Could not resize file");
> +        }
> +        return result;
> +    default:
> +        result = -ENOTSUP;
> +        error_setg(errp, "Unsupported preallocation mode: %s",
> +                   PreallocMode_lookup[prealloc]);
> +        return result;
> +    }
> +}
> +
>  static int raw_truncate(BlockDriverState *bs, int64_t offset,
>                          PreallocMode prealloc, Error **errp)
>  {
> @@ -1675,72 +1750,9 @@ static int raw_create(const char *filename, QemuOpts *opts, Error **errp)
>  #endif
>      }
>
> -    switch (prealloc) {
> -#ifdef CONFIG_POSIX_FALLOCATE
> -    case PREALLOC_MODE_FALLOC:
> -        /*
> -         * Truncating before posix_fallocate() makes it about twice slower on
> -         * file systems that do not support fallocate(), trying to check if a
> -         * block is allocated before allocating it, so don't do that here.
> -         */
> -        result = -posix_fallocate(fd, 0, total_size);
> -        if (result != 0) {
> -            /* posix_fallocate() doesn't set errno. */
> -            error_setg_errno(errp, -result,
> -                             "Could not preallocate data for the new file");
> -        }
> -        break;
> -#endif
> -    case PREALLOC_MODE_FULL:
> -    {
> -        int64_t num = 0, left = total_size;
> -
> -        /*
> -         * Knowing the final size from the beginning could allow the file
> -         * system driver to do less allocations and possibly avoid
> -         * fragmentation of the file.
> -         */
> -        if (ftruncate(fd, total_size) != 0) {
> -            result = -errno;
> -            error_setg_errno(errp, -result, "Could not resize file");
> -            goto out_close;
> -        }
> -
> -        buf = g_malloc0(65536);
> -
> -        while (left > 0) {
> -            num = MIN(left, 65536);
> -            result = write(fd, buf, num);
> -            if (result < 0) {
> -                result = -errno;
> -                error_setg_errno(errp, -result,
> -                                 "Could not write to the new file");
> -                break;
> -            }
> -            left -= result;
> -        }
> -        if (result >= 0) {
> -            result = fsync(fd);
> -            if (result < 0) {
> -                result = -errno;
> -                error_setg_errno(errp, -result,
> -                                 "Could not flush new file to disk");
> -            }
> -        }
> -        g_free(buf);
> -        break;
> -    }
> -    case PREALLOC_MODE_OFF:
> -        if (ftruncate(fd, total_size) != 0) {
> -            result = -errno;
> -            error_setg_errno(errp, -result, "Could not resize file");
> -        }
> -        break;
> -    default:
> -        result = -ENOTSUP;
> -        error_setg(errp, "Unsupported preallocation mode: %s",
> -                   PreallocMode_lookup[prealloc]);
> -        break;
> +    result = raw_regular_truncate(fd, total_size, prealloc, errp);
> +    if (result < 0) {
> +        goto out_close;
>      }
>
>  out_close:
>

Patch
diff mbox

diff --git a/block/file-posix.c b/block/file-posix.c
index cab77db963..e6b6fa30ce 100644
--- a/block/file-posix.c
+++ b/block/file-posix.c
@@ -1407,6 +1407,81 @@  static void raw_close(BlockDriverState *bs)
     }
 }
 
+static int raw_regular_truncate(int fd, int64_t offset, PreallocMode prealloc,
+                                Error **errp)
+{
+    int result = 0;
+    char *buf;
+
+    switch (prealloc) {
+#ifdef CONFIG_POSIX_FALLOCATE
+    case PREALLOC_MODE_FALLOC:
+        /*
+         * Truncating before posix_fallocate() makes it about twice slower on
+         * file systems that do not support fallocate(), trying to check if a
+         * block is allocated before allocating it, so don't do that here.
+         */
+        result = -posix_fallocate(fd, 0, offset);
+        if (result != 0) {
+            /* posix_fallocate() doesn't set errno. */
+            error_setg_errno(errp, -result,
+                             "Could not preallocate data for the new file");
+        }
+        return result;
+#endif
+    case PREALLOC_MODE_FULL:
+    {
+        int64_t num = 0, left = offset;
+
+        /*
+         * Knowing the final size from the beginning could allow the file
+         * system driver to do less allocations and possibly avoid
+         * fragmentation of the file.
+         */
+        if (ftruncate(fd, offset) != 0) {
+            result = -errno;
+            error_setg_errno(errp, -result, "Could not resize file");
+            return result;
+        }
+
+        buf = g_malloc0(65536);
+
+        while (left > 0) {
+            num = MIN(left, 65536);
+            result = write(fd, buf, num);
+            if (result < 0) {
+                result = -errno;
+                error_setg_errno(errp, -result,
+                                 "Could not write to the new file");
+                break;
+            }
+            left -= result;
+        }
+        if (result >= 0) {
+            result = fsync(fd);
+            if (result < 0) {
+                result = -errno;
+                error_setg_errno(errp, -result,
+                                 "Could not flush new file to disk");
+            }
+        }
+        g_free(buf);
+        return result;
+    }
+    case PREALLOC_MODE_OFF:
+        if (ftruncate(fd, offset) != 0) {
+            result = -errno;
+            error_setg_errno(errp, -result, "Could not resize file");
+        }
+        return result;
+    default:
+        result = -ENOTSUP;
+        error_setg(errp, "Unsupported preallocation mode: %s",
+                   PreallocMode_lookup[prealloc]);
+        return result;
+    }
+}
+
 static int raw_truncate(BlockDriverState *bs, int64_t offset,
                         PreallocMode prealloc, Error **errp)
 {
@@ -1675,72 +1750,9 @@  static int raw_create(const char *filename, QemuOpts *opts, Error **errp)
 #endif
     }
 
-    switch (prealloc) {
-#ifdef CONFIG_POSIX_FALLOCATE
-    case PREALLOC_MODE_FALLOC:
-        /*
-         * Truncating before posix_fallocate() makes it about twice slower on
-         * file systems that do not support fallocate(), trying to check if a
-         * block is allocated before allocating it, so don't do that here.
-         */
-        result = -posix_fallocate(fd, 0, total_size);
-        if (result != 0) {
-            /* posix_fallocate() doesn't set errno. */
-            error_setg_errno(errp, -result,
-                             "Could not preallocate data for the new file");
-        }
-        break;
-#endif
-    case PREALLOC_MODE_FULL:
-    {
-        int64_t num = 0, left = total_size;
-
-        /*
-         * Knowing the final size from the beginning could allow the file
-         * system driver to do less allocations and possibly avoid
-         * fragmentation of the file.
-         */
-        if (ftruncate(fd, total_size) != 0) {
-            result = -errno;
-            error_setg_errno(errp, -result, "Could not resize file");
-            goto out_close;
-        }
-
-        buf = g_malloc0(65536);
-
-        while (left > 0) {
-            num = MIN(left, 65536);
-            result = write(fd, buf, num);
-            if (result < 0) {
-                result = -errno;
-                error_setg_errno(errp, -result,
-                                 "Could not write to the new file");
-                break;
-            }
-            left -= result;
-        }
-        if (result >= 0) {
-            result = fsync(fd);
-            if (result < 0) {
-                result = -errno;
-                error_setg_errno(errp, -result,
-                                 "Could not flush new file to disk");
-            }
-        }
-        g_free(buf);
-        break;
-    }
-    case PREALLOC_MODE_OFF:
-        if (ftruncate(fd, total_size) != 0) {
-            result = -errno;
-            error_setg_errno(errp, -result, "Could not resize file");
-        }
-        break;
-    default:
-        result = -ENOTSUP;
-        error_setg(errp, "Unsupported preallocation mode: %s",
-                   PreallocMode_lookup[prealloc]);
-        break;
+    result = raw_regular_truncate(fd, total_size, prealloc, errp);
+    if (result < 0) {
+        goto out_close;
     }
 
 out_close: