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authorKent Overstreet <kent.overstreet@linux.dev>2024-01-16 17:00:02 -0500
committerKent Overstreet <kent.overstreet@linux.dev>2024-01-16 17:17:23 -0500
commitb5fd066153c40a70a29caa1ea7987723ab687763 (patch)
tree6d43a8b0a90d549a54c65565ac96c92b3e84b594 /include/linux/ioprio.h
parent06ff8b55b70fda44d91b31b5511fafd1680a8934 (diff)
Move c_src dirs back to toplevel
We just wanted c sourcefiles out of the top level, not c source directories. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Diffstat (limited to 'include/linux/ioprio.h')
-rw-r--r--include/linux/ioprio.h46
1 files changed, 46 insertions, 0 deletions
diff --git a/include/linux/ioprio.h b/include/linux/ioprio.h
new file mode 100644
index 00000000..822c64a2
--- /dev/null
+++ b/include/linux/ioprio.h
@@ -0,0 +1,46 @@
+#ifndef IOPRIO_H
+#define IOPRIO_H
+
+/*
+ * Gives us 8 prio classes with 13-bits of data for each class
+ */
+#define IOPRIO_BITS (16)
+#define IOPRIO_CLASS_SHIFT (13)
+#define IOPRIO_PRIO_MASK ((1UL << IOPRIO_CLASS_SHIFT) - 1)
+
+#define IOPRIO_PRIO_CLASS(mask) ((mask) >> IOPRIO_CLASS_SHIFT)
+#define IOPRIO_PRIO_DATA(mask) ((mask) & IOPRIO_PRIO_MASK)
+#define IOPRIO_PRIO_VALUE(class, data) (((class) << IOPRIO_CLASS_SHIFT) | data)
+
+#define ioprio_valid(mask) (IOPRIO_PRIO_CLASS((mask)) != IOPRIO_CLASS_NONE)
+
+/*
+ * These are the io priority groups as implemented by CFQ. RT is the realtime
+ * class, it always gets premium service. BE is the best-effort scheduling
+ * class, the default for any process. IDLE is the idle scheduling class, it
+ * is only served when no one else is using the disk.
+ */
+enum {
+ IOPRIO_CLASS_NONE,
+ IOPRIO_CLASS_RT,
+ IOPRIO_CLASS_BE,
+ IOPRIO_CLASS_IDLE,
+};
+
+/*
+ * 8 best effort priority levels are supported
+ */
+#define IOPRIO_BE_NR (8)
+
+enum {
+ IOPRIO_WHO_PROCESS = 1,
+ IOPRIO_WHO_PGRP,
+ IOPRIO_WHO_USER,
+};
+
+/*
+ * Fallback BE priority
+ */
+#define IOPRIO_NORM (4)
+
+#endif