From: Joelle van Dyne <j@getutm.app>
To: qemu-devel@nongnu.org
Cc: Kevin Wolf <kwolf@redhat.com>, Joelle van Dyne <j@getutm.app>,
"open list:raw" <qemu-block@nongnu.org>,
Max Reitz <mreitz@redhat.com>
Subject: [PATCH v8 09/11] block: check availablity for preadv/pwritev on mac
Date: Fri, 22 Jan 2021 20:56:30 -0800 [thread overview]
Message-ID: <20210123045632.18482-10-j@getutm.app> (raw)
In-Reply-To: <20210123045632.18482-1-j@getutm.app>
macOS 11/iOS 14 added preadv/pwritev APIs. Due to weak linking, configure
will succeed with CONFIG_PREADV even when targeting a lower OS version.
We therefore need to check at run time if we can actually use these APIs.
Signed-off-by: Joelle van Dyne <j@getutm.app>
---
block/file-posix.c | 33 +++++++++++++++++++++++++++++++++
1 file changed, 33 insertions(+)
diff --git a/block/file-posix.c b/block/file-posix.c
index 666d3e7504..6473f84db8 100644
--- a/block/file-posix.c
+++ b/block/file-posix.c
@@ -1386,17 +1386,50 @@ static int handle_aiocb_flush(void *opaque)
#ifdef CONFIG_PREADV
static bool preadv_present = true;
+static bool preadv_checked;
static ssize_t
qemu_preadv(int fd, const struct iovec *iov, int nr_iov, off_t offset)
{
+#ifdef CONFIG_DARWIN /* preadv introduced in macOS 11 */
+ if (unlikely(!preadv_checked)) {
+ if (__builtin_available(macOS 11, iOS 14, watchOS 7, tvOS 14, *)) {
+ preadv_checked = true;
+ } else {
+ preadv_present = false;
+ return -ENOSYS;
+ }
+ }
+ /* Now we suppress the availability warning since we use the cached check */
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunguarded-availability-new"
+ return preadv(fd, iov, nr_iov, offset);
+#pragma clang diagnostic pop
+#else /* CONFIG_DARWIN */
return preadv(fd, iov, nr_iov, offset);
+#endif
}
static ssize_t
qemu_pwritev(int fd, const struct iovec *iov, int nr_iov, off_t offset)
{
+#ifdef CONFIG_DARWIN /* preadv introduced in macOS 11 */
+ if (unlikely(!preadv_checked)) {
+ if (__builtin_available(macOS 11, iOS 14, watchOS 7, tvOS 14, *)) {
+ preadv_checked = true;
+ } else {
+ preadv_present = false;
+ return -ENOSYS;
+ }
+ }
+ /* Now we suppress the availability warning since we use the cached check */
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunguarded-availability-new"
+ return pwritev(fd, iov, nr_iov, offset);
+#pragma clang diagnostic pop
+#else /* CONFIG_DARWIN */
return pwritev(fd, iov, nr_iov, offset);
+#endif
}
#else
--
2.28.0
next prev parent reply other threads:[~2021-01-23 5:02 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-01-23 4:56 [PATCH v8 00/11] iOS and Apple Silicon host support Joelle van Dyne
2021-01-23 4:56 ` [PATCH v8 01/11] block: feature detection for host block support Joelle van Dyne
2021-01-23 4:56 ` [PATCH v8 02/11] configure: cross-compiling with empty cross_prefix Joelle van Dyne
2021-01-23 4:56 ` [PATCH v8 03/11] configure: check for sys/disk.h Joelle van Dyne
2021-01-23 4:56 ` [PATCH v8 04/11] slirp: feature detection for smbd Joelle van Dyne
2021-01-23 4:56 ` [PATCH v8 05/11] osdep: build with non-working system() function Joelle van Dyne
2021-01-23 4:56 ` [PATCH v8 06/11] darwin: remove redundant dependency declaration Joelle van Dyne
2021-01-23 4:56 ` [PATCH v8 07/11] darwin: fix cross-compiling for Darwin Joelle van Dyne
2021-01-23 4:56 ` [PATCH v8 08/11] configure: cross compile should use x86_64 cpu_family Joelle van Dyne
2021-01-23 4:56 ` Joelle van Dyne [this message]
2021-01-23 13:52 ` [PATCH v8 09/11] block: check availablity for preadv/pwritev on mac Peter Maydell
2021-01-23 20:00 ` Joelle van Dyne
2021-01-23 20:04 ` Joelle van Dyne
2021-01-23 4:56 ` [PATCH v8 10/11] darwin: detect CoreAudio for build Joelle van Dyne
2021-01-23 4:56 ` [PATCH v8 11/11] darwin: remove 64-bit build detection on 32-bit OS Joelle van Dyne
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