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-rw-r--r--include/linux/drbd_limits.h137
1 files changed, 137 insertions, 0 deletions
diff --git a/include/linux/drbd_limits.h b/include/linux/drbd_limits.h
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+++ b/include/linux/drbd_limits.h
@@ -0,0 +1,137 @@
+/*
+ drbd_limits.h
+ This file is part of DRBD by Philipp Reisner and Lars Ellenberg.
+*/
+
+/*
+ * Our current limitations.
+ * Some of them are hard limits,
+ * some of them are arbitrary range limits, that make it easier to provide
+ * feedback about nonsense settings for certain configurable values.
+ */
+
+#ifndef DRBD_LIMITS_H
+#define DRBD_LIMITS_H 1
+
+#define DEBUG_RANGE_CHECK 0
+
+#define DRBD_MINOR_COUNT_MIN 1
+#define DRBD_MINOR_COUNT_MAX 255
+
+#define DRBD_DIALOG_REFRESH_MIN 0
+#define DRBD_DIALOG_REFRESH_MAX 600
+
+/* valid port number */
+#define DRBD_PORT_MIN 1
+#define DRBD_PORT_MAX 0xffff
+
+/* startup { */
+ /* if you want more than 3.4 days, disable */
+#define DRBD_WFC_TIMEOUT_MIN 0
+#define DRBD_WFC_TIMEOUT_MAX 300000
+#define DRBD_WFC_TIMEOUT_DEF 0
+
+#define DRBD_DEGR_WFC_TIMEOUT_MIN 0
+#define DRBD_DEGR_WFC_TIMEOUT_MAX 300000
+#define DRBD_DEGR_WFC_TIMEOUT_DEF 0
+
+#define DRBD_OUTDATED_WFC_TIMEOUT_MIN 0
+#define DRBD_OUTDATED_WFC_TIMEOUT_MAX 300000
+#define DRBD_OUTDATED_WFC_TIMEOUT_DEF 0
+/* }*/
+
+/* net { */
+ /* timeout, unit centi seconds
+ * more than one minute timeout is not usefull */
+#define DRBD_TIMEOUT_MIN 1
+#define DRBD_TIMEOUT_MAX 600
+#define DRBD_TIMEOUT_DEF 60 /* 6 seconds */
+
+ /* active connection retries when C_WF_CONNECTION */
+#define DRBD_CONNECT_INT_MIN 1
+#define DRBD_CONNECT_INT_MAX 120
+#define DRBD_CONNECT_INT_DEF 10 /* seconds */
+
+ /* keep-alive probes when idle */
+#define DRBD_PING_INT_MIN 1
+#define DRBD_PING_INT_MAX 120
+#define DRBD_PING_INT_DEF 10
+
+ /* timeout for the ping packets.*/
+#define DRBD_PING_TIMEO_MIN 1
+#define DRBD_PING_TIMEO_MAX 100
+#define DRBD_PING_TIMEO_DEF 5
+
+ /* max number of write requests between write barriers */
+#define DRBD_MAX_EPOCH_SIZE_MIN 1
+#define DRBD_MAX_EPOCH_SIZE_MAX 20000
+#define DRBD_MAX_EPOCH_SIZE_DEF 2048
+
+ /* I don't think that a tcp send buffer of more than 10M is usefull */
+#define DRBD_SNDBUF_SIZE_MIN 0
+#define DRBD_SNDBUF_SIZE_MAX (10<<20)
+#define DRBD_SNDBUF_SIZE_DEF 0
+
+#define DRBD_RCVBUF_SIZE_MIN 0
+#define DRBD_RCVBUF_SIZE_MAX (10<<20)
+#define DRBD_RCVBUF_SIZE_DEF 0
+
+ /* @4k PageSize -> 128kB - 512MB */
+#define DRBD_MAX_BUFFERS_MIN 32
+#define DRBD_MAX_BUFFERS_MAX 131072
+#define DRBD_MAX_BUFFERS_DEF 2048
+
+ /* @4k PageSize -> 4kB - 512MB */
+#define DRBD_UNPLUG_WATERMARK_MIN 1
+#define DRBD_UNPLUG_WATERMARK_MAX 131072
+#define DRBD_UNPLUG_WATERMARK_DEF (DRBD_MAX_BUFFERS_DEF/16)
+
+ /* 0 is disabled.
+ * 200 should be more than enough even for very short timeouts */
+#define DRBD_KO_COUNT_MIN 0
+#define DRBD_KO_COUNT_MAX 200
+#define DRBD_KO_COUNT_DEF 0
+/* } */
+
+/* syncer { */
+ /* FIXME allow rate to be zero? */
+#define DRBD_RATE_MIN 1
+/* channel bonding 10 GbE, or other hardware */
+#define DRBD_RATE_MAX (4 << 20)
+#define DRBD_RATE_DEF 250 /* kb/second */
+
+ /* less than 7 would hit performance unneccessarily.
+ * 3833 is the largest prime that still does fit
+ * into 64 sectors of activity log */
+#define DRBD_AL_EXTENTS_MIN 7
+#define DRBD_AL_EXTENTS_MAX 3833
+#define DRBD_AL_EXTENTS_DEF 127
+
+#define DRBD_AFTER_MIN -1
+#define DRBD_AFTER_MAX 255
+#define DRBD_AFTER_DEF -1
+
+/* } */
+
+/* drbdsetup XY resize -d Z
+ * you are free to reduce the device size to nothing, if you want to.
+ * the upper limit with 64bit kernel, enough ram and flexible meta data
+ * is 16 TB, currently. */
+/* DRBD_MAX_SECTORS */
+#define DRBD_DISK_SIZE_SECT_MIN 0
+#define DRBD_DISK_SIZE_SECT_MAX (16 * (2LLU << 30))
+#define DRBD_DISK_SIZE_SECT_DEF 0 /* = disabled = no user size... */
+
+#define DRBD_ON_IO_ERROR_DEF EP_PASS_ON
+#define DRBD_FENCING_DEF FP_DONT_CARE
+#define DRBD_AFTER_SB_0P_DEF ASB_DISCONNECT
+#define DRBD_AFTER_SB_1P_DEF ASB_DISCONNECT
+#define DRBD_AFTER_SB_2P_DEF ASB_DISCONNECT
+#define DRBD_RR_CONFLICT_DEF ASB_DISCONNECT
+
+#define DRBD_MAX_BIO_BVECS_MIN 0
+#define DRBD_MAX_BIO_BVECS_MAX 128
+#define DRBD_MAX_BIO_BVECS_DEF 0
+
+#undef RANGE
+#endif