X-Git-Url: https://git.kernel.dk/?a=blobdiff_plain;f=engines%2Fskeleton_external.c;h=56f89f957b5f502ccfe0add680ac80c6ef9d4a85;hb=07dff7d1d614b33e3a6d3e3ade38ce648b53a632;hp=785b9a660a7fdfd2921eac125f70d1750c394fad;hpb=e2a26d2c2a75861494f6fc4046a37a71874bd59a;p=fio.git

diff --git a/engines/skeleton_external.c b/engines/skeleton_external.c
index 785b9a66..56f89f95 100644
--- a/engines/skeleton_external.c
+++ b/engines/skeleton_external.c
@@ -3,7 +3,8 @@
  *
  * Should be compiled with:
  *
- * gcc -Wall -O2 -g -shared -rdynamic -fPIC -o engine.o engine.c
+ * gcc -Wall -O2 -g -shared -rdynamic -fPIC -o skeleton_external.o skeleton_external.c
+ * (also requires -D_GNU_SOURCE -DCONFIG_STRSEP on Linux)
  *
  */
 #include <stdio.h>
@@ -13,7 +14,7 @@
 #include <assert.h>
 
 #include "../fio.h"
-#include "../os.h"
+#include "../optgroup.h"
 
 /*
  * The core of the module is identical to the ones included with fio,
@@ -21,6 +22,32 @@
  * for external modules, they should be gotten through dlsym()
  */
 
+/*
+ * The io engine can define its own options within the io engine source.
+ * The option member must not be at offset 0, due to the way fio parses
+ * the given option. Just add a padding pointer unless the io engine has
+ * something usable.
+ */
+struct fio_skeleton_options {
+	void *pad; /* avoid ->off1 of fio_option becomes 0 */
+	unsigned int dummy;
+};
+
+static struct fio_option options[] = {
+	{
+		.name	= "dummy",
+		.lname	= "ldummy",
+		.type	= FIO_OPT_STR_SET,
+		.off1	= offsetof(struct fio_skeleton_options, dummy),
+		.help	= "Set dummy",
+		.category = FIO_OPT_C_ENGINE, /* always use this */
+		.group	= FIO_OPT_G_INVALID, /* this can be different */
+	},
+	{
+		.name	= NULL,
+	},
+};
+
 /*
  * The ->event() hook is called to match an event number with an io_u.
  * After the core has called ->getevents() and it has returned eg 3,
@@ -38,8 +65,8 @@ static struct io_u *fio_skeleton_event(struct thread_data *td, int event)
  * which may then be retrieved by calling the ->event() hook with the event
  * numbers. Required.
  */
-static int fio_skeleton_getevents(struct thread_data *td, int min, int max,
-				  struct timespec *t)
+static int fio_skeleton_getevents(struct thread_data *td, unsigned int min,
+				  unsigned int max, const struct timespec *t)
 {
 	return 0;
 }
@@ -60,19 +87,29 @@ static int fio_skeleton_cancel(struct thread_data *td, struct io_u *io_u)
  *
  * The io engine must transfer in the direction noted by io_u->ddir
  * to the buffer pointed to by io_u->xfer_buf for as many bytes as
- * io_u->xfer_buflen. Residual data count may be set in io_u->residual
- * for a short read/write. Should return 0 for io_u complete, < 0 for
- * an error, and > 0 for the number of bytes transferred.
+ * io_u->xfer_buflen. Residual data count may be set in io_u->resid
+ * for a short read/write.
  */
 static int fio_skeleton_queue(struct thread_data *td, struct io_u *io_u)
 {
-	return 0;
+	/*
+	 * Double sanity check to catch errant write on a readonly setup
+	 */
+	fio_ro_check(td, io_u);
+
+	/*
+	 * Could return FIO_Q_QUEUED for a queued request,
+	 * FIO_Q_COMPLETED for a completed request, and FIO_Q_BUSY
+	 * if we could queue no more at this point (you'd have to
+	 * define ->commit() to handle that.
+	 */
+	return FIO_Q_COMPLETED;
 }
 
 /*
  * The ->prep() function is called for each io_u prior to being submitted
  * with ->queue(). This hook allows the io engine to perform any
- * preperatory actions on the io_u, before being submitted. Not required.
+ * preparatory actions on the io_u, before being submitted. Not required.
  */
 static int fio_skeleton_prep(struct thread_data *td, struct io_u *io_u)
 {
@@ -90,7 +127,7 @@ static int fio_skeleton_init(struct thread_data *td)
 }
 
 /*
- * This is paired with the ->init() funtion and is called when a thread is
+ * This is paired with the ->init() function and is called when a thread is
  * done doing io. Should tear down anything setup by the ->init() function.
  * Not required.
  */
@@ -98,9 +135,26 @@ static void fio_skeleton_cleanup(struct thread_data *td)
 {
 }
 
+/*
+ * Hook for opening the given file. Unless the engine has special
+ * needs, it usually just provides generic_open_file() as the handler.
+ */
+static int fio_skeleton_open(struct thread_data *td, struct fio_file *f)
+{
+	return generic_open_file(td, f);
+}
+
+/*
+ * Hook for closing a file. See fio_skeleton_open().
+ */
+static int fio_skeleton_close(struct thread_data *td, struct fio_file *f)
+{
+	return generic_close_file(td, f);
+}
+
 /*
  * Note that the structure is exported, so that fio can get it via
- * dlsym(..., "ioengine");
+ * dlsym(..., "ioengine"); for (and only for) external engines.
  */
 struct ioengine_ops ioengine = {
 	.name		= "engine_name",
@@ -112,4 +166,8 @@ struct ioengine_ops ioengine = {
 	.getevents	= fio_skeleton_getevents,
 	.event		= fio_skeleton_event,
 	.cleanup	= fio_skeleton_cleanup,
+	.open_file	= fio_skeleton_open,
+	.close_file	= fio_skeleton_close,
+	.options	= options,
+	.option_struct_size	= sizeof(struct fio_skeleton_options),
 };