[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Qemu-block] [PATCH v3 5/9] file-posix: Support auto-read-only option
From: |
Kevin Wolf |
Subject: |
[Qemu-block] [PATCH v3 5/9] file-posix: Support auto-read-only option |
Date: |
Wed, 17 Oct 2018 18:41:56 +0200 |
If read-only=off, but auto-read-only=on is given, open the file
read-write if we have the permissions, but instead of erroring out for
read-only files, just degrade to read-only.
Signed-off-by: Kevin Wolf <address@hidden>
---
block/file-posix.c | 19 ++++++++++++++++---
1 file changed, 16 insertions(+), 3 deletions(-)
diff --git a/block/file-posix.c b/block/file-posix.c
index 2da3a76355..0c1b81ce4b 100644
--- a/block/file-posix.c
+++ b/block/file-posix.c
@@ -527,9 +527,22 @@ static int raw_open_common(BlockDriverState *bs, QDict
*options,
s->fd = -1;
fd = qemu_open(filename, s->open_flags, 0644);
- if (fd < 0) {
- ret = -errno;
- error_setg_errno(errp, errno, "Could not open '%s'", filename);
+ ret = fd < 0 ? -errno : 0;
+
+ if (ret == -EACCES || ret == -EROFS) {
+ /* Try to degrade to read-only, but if it doesn't work, still use the
+ * normal error message. */
+ if (bdrv_apply_auto_read_only(bs, NULL, NULL) == 0) {
+ bdrv_flags &= ~BDRV_O_RDWR;
+ raw_parse_flags(bdrv_flags, &s->open_flags);
+ assert(!(s->open_flags & O_CREAT));
+ fd = qemu_open(filename, s->open_flags);
+ ret = fd < 0 ? -errno : 0;
+ }
+ }
+
+ if (ret < 0) {
+ error_setg_errno(errp, -ret, "Could not open '%s'", filename);
if (ret == -EROFS) {
ret = -EACCES;
}
--
2.19.1
- [Qemu-block] [PATCH v3 0/9] block: Add auto-read-only option, Kevin Wolf, 2018/10/17
- [Qemu-block] [PATCH v3 5/9] file-posix: Support auto-read-only option,
Kevin Wolf <=
- [Qemu-block] [PATCH v3 2/9] block: Add auto-read-only option, Kevin Wolf, 2018/10/17
- [Qemu-block] [PATCH v3 1/9] block: Update flags in bdrv_set_read_only(), Kevin Wolf, 2018/10/17
- [Qemu-block] [PATCH v3 7/9] gluster: Support auto-read-only option, Kevin Wolf, 2018/10/17
- [Qemu-block] [PATCH v3 4/9] nbd: Support auto-read-only option, Kevin Wolf, 2018/10/17
- [Qemu-block] [PATCH v3 9/9] block: Make auto-read-only=on default for -drive, Kevin Wolf, 2018/10/17
- [Qemu-block] [PATCH v3 6/9] curl: Support auto-read-only option, Kevin Wolf, 2018/10/17