9os

commit 19176444e19f44995419389945871864a8f3ed43
parent 8a925b295f53d5412f99972b8dc18c43455c52b7
Author: Roberto Vargas <roberto.vargas@arm.com>
Date:   Thu, 16 May 2019 10:03:13 +0100

[dev] Add sync() and fsync()

These functions synchronize the buffered data in every driver.
At this moment all the drivers have a dummy sync function,
but some of them, like for example devuart, should have
a proper sync function.

Change-Id: I097c65d5b5a2fbd5166bdc41382ffd76632a7c4a

Diffstat:
M
drivers/dev.c
 | 
35
+++++++++++++++++++++++++++++++++++
M
drivers/dev.h
 | 
5
+++++
M
drivers/devar.c
 | 
1
+
M
drivers/devcons.c
 | 
1
+
M
drivers/devfip.c
 | 
1
+
M
drivers/devroot.c
 | 
1
+
M
drivers/devuart.c
 | 
1
+
M
include/rcode/io.h
 | 
2
++

8 files changed, 47 insertions(+), 0 deletions(-)
diff --git a/drivers/dev.c b/drivers/dev.c
@@ -485,6 +485,35 @@ seek(int fd, long off, int whence)
 	return devtab[c->type]->seek(c, off, whence);
 }
 
+int
+fsync(int fd)
+{
+	Chan *c;
+
+	if ((c = fd2chan(fd)) == NULL)
+		return -1;
+
+        if (c->qid & CHDIR) {
+                errno = EISDIR;
+                return -1;
+        }
+
+	return devtab[c->type]->sync(c, SYNCDEV);
+}
+
+void
+sync(void)
+{
+	Chan *c;
+        Dev * const *dp;
+
+        for (dp = devtab; *dp; ++dp) {
+		c = attach((*dp)->id, 0);
+		devtab[c->type]->sync(c, SYNCALL);
+		chanclose(c);
+	}
+}
+
 Chan *
 deverrmount(Chan *c, char *spec)
 {
@@ -523,6 +552,12 @@ devseek(Chan *c, long off, int whence)
 	return 0;
 }
 
+int
+devsync(Chan *c, int what)
+{
+	return 0;
+}
+
 static int
 addmntpoint(Chan *c, char *new)
 {
diff --git a/drivers/dev.h b/drivers/dev.h
@@ -7,6 +7,9 @@
 #define NODEV     255
 #define CHDIR     (1 << 15)
 
+#define SYNCDEV   0
+#define SYNCALL   1
+
 typedef struct dev Dev;
 typedef struct chan Chan;
 typedef struct dirtab Dirtab;
@@ -28,6 +31,7 @@ struct dev {
 	int (*read)(Chan *c, void *buf, int n);
 	int (*write)(Chan *c, void *buf, int n);
 	int (*seek)(Chan *c, long off, int whence);
+	int (*sync)(Chan *c, int what);
 	Chan *(*clone)(Chan *c, Chan *nc);
 	Chan *(*attach)(int id, int dev);
         Chan *(*mount)(Chan *c, char *spec);
@@ -61,6 +65,7 @@ extern void devlink(void);
 
 extern Chan *devattach(int id, int dev);
 extern int devseek(Chan *c, long off, int whence);
+extern int devsync(Chan *c, int what);
 extern Chan *devclone(Chan *c, Chan *nc);
 extern int devgen(Chan *c,
                   const Dirtab *tab, int ntab,
diff --git a/drivers/devar.c b/drivers/devar.c
@@ -215,4 +215,5 @@ const Dev ardevtab = {
 	.write = deverrwrite,
 	.mount = armount,
 	.seek = devseek,
+	.sync = devsync,
 };
diff --git a/drivers/devcons.c b/drivers/devcons.c
@@ -379,4 +379,5 @@ const Dev consdevtab = {
 	.read = consread,
 	.write = conswrite,
 	.seek = deverrseek,
+	.sync = devsync,
 };
diff --git a/drivers/devfip.c b/drivers/devfip.c
@@ -298,4 +298,5 @@ const Dev fipdevtab = {
 	.write = deverrwrite,
 	.mount = fipmount,
 	.seek = devseek,
+	.sync = devsync,
 };
diff --git a/drivers/devroot.c b/drivers/devroot.c
@@ -122,4 +122,5 @@ const Dev rootdevtab = {
 	.write = deverrwrite,
 	.mount = deverrmount,
 	.seek = devseek,
+	.sync = devsync,
 };
diff --git a/drivers/devuart.c b/drivers/devuart.c
@@ -255,4 +255,5 @@ const Dev uartdevtab = {
 	.write = uartwrite,
 	.mount = deverrmount,
 	.seek = deverrseek,
+	.sync = devsync,
 };
diff --git a/include/rcode/io.h b/include/rcode/io.h
@@ -60,6 +60,8 @@ extern int write(int fd, void *buf, int n);
 extern int seek(int fd, long off, int whence);
 extern int bind(char *path, char *where);
 extern int stat(char *path, void *buf, int n);
+extern int fsync(int fd);
+extern void sync(void);
 
 extern int kin, kout, kerr;