biosdevname/SOURCES/0001-Add-buffer-read-helper-using-read-explicitly.patch

169 lines
3.6 KiB
Diff

From f64c3f549eda36d11b5690117173b0847535ebbe Mon Sep 17 00:00:00 2001
From: Takashi Iwai <tiwai@suse.de>
Date: Mon, 24 Aug 2020 14:40:17 +0200
Subject: [PATCH] Add buffer read helper using read explicitly
Since mmap can't work well with a sysfs file, we need to read the
contents explicitly via read, even if USE_MMAP is enabled.
Provide a new helper, __mem_cunk(), that does behave like mem_chunk()
but with the extra use_mmap argument to specify the method to read a
file.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
CC: Thomas Renninger <trenn@suse.de>
CC: Michal Suchanek <msuchanek@suse.com>
---
src/dmidecode/util.c | 82 ++++++++++++++++++++++++++++----------------
src/dmidecode/util.h | 1 +
2 files changed, 53 insertions(+), 30 deletions(-)
diff --git a/src/dmidecode/util.c b/src/dmidecode/util.c
index ea06663..09934ea 100644
--- a/src/dmidecode/util.c
+++ b/src/dmidecode/util.c
@@ -47,7 +47,6 @@
#include "types.h"
#include "util.h"
-#ifndef USE_MMAP
static int myread(int fd, u8 *buf, size_t count, const char *prefix)
{
ssize_t r=1;
@@ -78,7 +77,6 @@ static int myread(int fd, u8 *buf, size_t count, const char *prefix)
return 0;
}
-#endif
int checksum(const u8 *buf, size_t len)
{
@@ -94,28 +92,13 @@ int checksum(const u8 *buf, size_t len)
* Copy a physical memory chunk into a memory buffer.
* This function allocates memory.
*/
-void *mem_chunk(size_t base, size_t len, const char *devmem)
-{
- void *p;
- int fd;
#ifdef USE_MMAP
+static void *mem_chunk_mmap(size_t base, size_t len, const char *devmem,
+ int fd, void *p)
+{
size_t mmoffset;
void *mmp;
-#endif
-
- if((fd=open(devmem, O_RDONLY))==-1)
- {
- return NULL;
- }
-
- if((p=malloc(len))==NULL)
- {
- perror("malloc");
- close(fd);
- return NULL;
- }
-
-#ifdef USE_MMAP
+
#ifdef _SC_PAGESIZE
mmoffset=base%sysconf(_SC_PAGESIZE);
#else
@@ -129,8 +112,6 @@ void *mem_chunk(size_t base, size_t len, const char *devmem)
mmp=mmap(0, mmoffset+len, PROT_READ, MAP_SHARED, fd, base-mmoffset);
if(mmp==MAP_FAILED)
{
- free(p);
- close(fd);
return NULL;
}
@@ -141,26 +122,67 @@ void *mem_chunk(size_t base, size_t len, const char *devmem)
fprintf(stderr, "%s: ", devmem);
perror("munmap");
}
-#else /* USE_MMAP */
+
+ return p;
+}
+#endif /* USE_MMAP */
+
+static void *mem_chunk_read(size_t base, size_t len, const char *devmem,
+ int fd, void *p)
+{
if(lseek(fd, base, SEEK_SET)==-1)
{
fprintf(stderr, "%s: ", devmem);
perror("lseek");
- free(p);
- close(fd);
return NULL;
}
if(myread(fd, p, len, devmem)==-1)
{
- free(p);
- close(fd);
return NULL;
}
-#endif /* USE_MMAP */
+
+ return p;
+}
+
+void *__mem_chunk(size_t base, size_t len, const char *devmem, int use_mmap)
+{
+ void *ret;
+ void *p;
+ int fd;
+
+#ifndef USE_MMAP
+ use_mmap = 0;
+#endif
+
+ if((fd=open(devmem, O_RDONLY))==-1)
+ {
+ return NULL;
+ }
+ if((p=malloc(len))==NULL)
+ {
+ perror("malloc");
+ close(fd);
+ return NULL;
+ }
+
+#ifdef USE_MMAP
+ if (use_mmap)
+ ret = mem_chunk_mmap(base, len, devmem, fd, p);
+ else
+#endif
+ ret = mem_chunk_read(base, len, devmem, fd, p);
+
if(close(fd)==-1)
perror(devmem);
+ if (!ret)
+ free(p);
- return p;
+ return ret;
+}
+
+void *mem_chunk(size_t base, size_t len, const char *devmem)
+{
+ return __mem_chunk(base, len, devmem, 1);
}
diff --git a/src/dmidecode/util.h b/src/dmidecode/util.h
index b546f64..90c411e 100644
--- a/src/dmidecode/util.h
+++ b/src/dmidecode/util.h
@@ -6,3 +6,4 @@
int checksum(const u8 *buf, size_t len);
void *mem_chunk(size_t base, size_t len, const char *devmem);
+void *__mem_chunk(size_t base, size_t len, const char *devmem, int use_mmap);
--
2.44.0