Allocate only one page at a time. Add proc interface.

1 files changed, 79 insertions, 0 deletions

diff --git a/litmus/color_proc.c b/litmus/color_proc.c
new file mode 100644
index 000000000000..1eba0740db9d
--- /dev/null
+++ b/litmus/color_proc.c
@@ -0,0 +1,79 @@
+#include <linux/module.h>
+#include <linux/sysctl.h>
+#include <linux/slab.h>
+
+#include <litmus/color.h>
+
+extern int color_sysctl_add_pages_data; /* litmus/color.c */
+
+static int zero = 0;
+static int one = 1;
+
+#define NR_PAGES_INDEX 1 /* location of nr_pages in the table below */
+static struct ctl_table color_table[] =
+{
+        {
+                .procname       = "add_pages",
+                .data           = &color_sysctl_add_pages_data,
+                .maxlen         = sizeof(int),
+                .mode           = 0644,
+                .proc_handler   = color_add_pages_handler,
+                .extra1         = &zero,
+                .extra2         = &one,
+        },
+        {
+                .procname       = "nr_pages",
+                .mode           = 0444,
+                .proc_handler   = color_nr_pages_handler,
+                .data           = NULL, /* dynamically later */
+                .maxlen         = 0,    /* also set later */
+        },
+        { }
+};
+
+static struct ctl_table litmus_table[] =
+{
+        {
+                .procname       = "color",
+                .mode           = 0555,
+                .child          = color_table,
+        },
+        { }
+};
+static struct ctl_table litmus_dir_table[] = {
+        {
+                .procname       = "litmus",
+                .mode           = 0555,
+                .child          = litmus_table,
+        },
+        { }
+};
+
+extern unsigned long nr_colors; /* litmus/color.c */
+
+/* must be called AFTER nr_colors is set */
+static int __init init_sysctl_nr_colors(void)
+{
+        int maxlen = ONE_COLOR_LEN * nr_colors;
+        color_table[NR_PAGES_INDEX].data = kmalloc(maxlen, GFP_KERNEL);
+        if (!color_table[NR_PAGES_INDEX].data) {
+                printk(KERN_WARNING "Could not allocate nr_pages buffer.\n");
+                return -ENOMEM;
+        }
+        color_table[NR_PAGES_INDEX].maxlen = maxlen;
+        return 0;
+}
+
+static struct ctl_table_header *litmus_sysctls;
+
+static int __init litmus_sysctl_init(void)
+{
+        litmus_sysctls = register_sysctl_table(litmus_dir_table);
+        if (!litmus_sysctls) {
+                printk(KERN_WARNING "Could not register LITMUS^RT sysctl.\n");
+                return -EFAULT;
+        }
+        return init_sysctl_nr_colors();
+}
+
+module_init(litmus_sysctl_init);