On 10/11/2023 18:52, Johannes Berg wrote:
From: Johannes Berg <johannes.b...@intel.com>
For the upcoming shared-memory time-travel external
optimisations, we need to be able to mmap/mremap
(and on error munmap). Add the necessary OS calls.
Signed-off-by: Johannes Berg <johannes.b...@intel.com>
---
arch/um/include/shared/os.h | 3 +++
arch/um/os-Linux/file.c | 28 ++++++++++++++++++++++++++++
2 files changed, 31 insertions(+)
diff --git a/arch/um/include/shared/os.h b/arch/um/include/shared/os.h
index 4fbe574eff4c..1a82c6548dd5 100644
--- a/arch/um/include/shared/os.h
+++ b/arch/um/include/shared/os.h
@@ -180,6 +180,9 @@ extern int os_eventfd(unsigned int initval, int flags);
extern int os_sendmsg_fds(int fd, const void *buf, unsigned int len,
const int *fds, unsigned int fds_num);
int os_poll(unsigned int n, const int *fds);
+void *os_mmap_rw_shared(int fd, size_t size);
+void *os_mremap_rw_shared(void *old_addr, size_t old_size, size_t new_size);
+void os_munmap(void *addr, size_t size);
/* start_up.c */
extern void os_early_checks(void);
diff --git a/arch/um/os-Linux/file.c b/arch/um/os-Linux/file.c
index c972dfeab9a3..c482850f27d8 100644
--- a/arch/um/os-Linux/file.c
+++ b/arch/um/os-Linux/file.c
@@ -17,6 +17,7 @@
#include <sys/stat.h>
#include <sys/sysmacros.h>
#include <sys/un.h>
+#include <sys/mman.h>
#include <sys/types.h>
#include <sys/eventfd.h>
#include <poll.h>
@@ -708,3 +709,30 @@ int os_poll(unsigned int n, const int *fds)
return -EIO;
}
+
+void *os_mmap_rw_shared(int fd, size_t size)
+{
+ void *res = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
+
+ if (res == MAP_FAILED)
+ return NULL;
+
+ return res;
+}
+
+void *os_mremap_rw_shared(void *old_addr, size_t old_size, size_t new_size)
+{
+ void *res;
+
+ res = mremap(old_addr, old_size, new_size, MREMAP_MAYMOVE, NULL);
+
+ if (res == MAP_FAILED)
+ return NULL;
+
+ return res;
+}
+
+void os_munmap(void *addr, size_t size)
+{
+ munmap(addr, size);
+}
os_munmap already exists as os_munmap_memory
The other two are OK.
--
Anton R. Ivanov
https://www.kot-begemot.co.uk/
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