xref: /openbmc/linux/include/linux/drbd_limits.h (revision 9a87ffc99ec8eb8d35eed7c4f816d75f5cc9662e)
1  /* SPDX-License-Identifier: GPL-2.0-only */
2  /*
3    drbd_limits.h
4    This file is part of DRBD by Philipp Reisner and Lars Ellenberg.
5  */
6  
7  /*
8   * Our current limitations.
9   * Some of them are hard limits,
10   * some of them are arbitrary range limits, that make it easier to provide
11   * feedback about nonsense settings for certain configurable values.
12   */
13  
14  #ifndef DRBD_LIMITS_H
15  #define DRBD_LIMITS_H 1
16  
17  #define DEBUG_RANGE_CHECK 0
18  
19  #define DRBD_MINOR_COUNT_MIN 1U
20  #define DRBD_MINOR_COUNT_MAX 255U
21  #define DRBD_MINOR_COUNT_DEF 32U
22  #define DRBD_MINOR_COUNT_SCALE '1'
23  
24  #define DRBD_VOLUME_MAX 65534U
25  
26  #define DRBD_DIALOG_REFRESH_MIN 0U
27  #define DRBD_DIALOG_REFRESH_MAX 600U
28  #define DRBD_DIALOG_REFRESH_SCALE '1'
29  
30  /* valid port number */
31  #define DRBD_PORT_MIN 1U
32  #define DRBD_PORT_MAX 0xffffU
33  #define DRBD_PORT_SCALE '1'
34  
35  /* startup { */
36    /* if you want more than 3.4 days, disable */
37  #define DRBD_WFC_TIMEOUT_MIN 0U
38  #define DRBD_WFC_TIMEOUT_MAX 300000U
39  #define DRBD_WFC_TIMEOUT_DEF 0U
40  #define DRBD_WFC_TIMEOUT_SCALE '1'
41  
42  #define DRBD_DEGR_WFC_TIMEOUT_MIN 0U
43  #define DRBD_DEGR_WFC_TIMEOUT_MAX 300000U
44  #define DRBD_DEGR_WFC_TIMEOUT_DEF 0U
45  #define DRBD_DEGR_WFC_TIMEOUT_SCALE '1'
46  
47  #define DRBD_OUTDATED_WFC_TIMEOUT_MIN 0U
48  #define DRBD_OUTDATED_WFC_TIMEOUT_MAX 300000U
49  #define DRBD_OUTDATED_WFC_TIMEOUT_DEF 0U
50  #define DRBD_OUTDATED_WFC_TIMEOUT_SCALE '1'
51  /* }*/
52  
53  /* net { */
54    /* timeout, unit centi seconds
55     * more than one minute timeout is not useful */
56  #define DRBD_TIMEOUT_MIN 1U
57  #define DRBD_TIMEOUT_MAX 600U
58  #define DRBD_TIMEOUT_DEF 60U       /* 6 seconds */
59  #define DRBD_TIMEOUT_SCALE '1'
60  
61   /* If backing disk takes longer than disk_timeout, mark the disk as failed */
62  #define DRBD_DISK_TIMEOUT_MIN 0U    /* 0 = disabled */
63  #define DRBD_DISK_TIMEOUT_MAX 6000U /* 10 Minutes */
64  #define DRBD_DISK_TIMEOUT_DEF 0U    /* disabled */
65  #define DRBD_DISK_TIMEOUT_SCALE '1'
66  
67    /* active connection retries when C_WF_CONNECTION */
68  #define DRBD_CONNECT_INT_MIN 1U
69  #define DRBD_CONNECT_INT_MAX 120U
70  #define DRBD_CONNECT_INT_DEF 10U   /* seconds */
71  #define DRBD_CONNECT_INT_SCALE '1'
72  
73    /* keep-alive probes when idle */
74  #define DRBD_PING_INT_MIN 1U
75  #define DRBD_PING_INT_MAX 120U
76  #define DRBD_PING_INT_DEF 10U
77  #define DRBD_PING_INT_SCALE '1'
78  
79   /* timeout for the ping packets.*/
80  #define DRBD_PING_TIMEO_MIN  1U
81  #define DRBD_PING_TIMEO_MAX  300U
82  #define DRBD_PING_TIMEO_DEF  5U
83  #define DRBD_PING_TIMEO_SCALE '1'
84  
85    /* max number of write requests between write barriers */
86  #define DRBD_MAX_EPOCH_SIZE_MIN 1U
87  #define DRBD_MAX_EPOCH_SIZE_MAX 20000U
88  #define DRBD_MAX_EPOCH_SIZE_DEF 2048U
89  #define DRBD_MAX_EPOCH_SIZE_SCALE '1'
90  
91    /* I don't think that a tcp send buffer of more than 10M is useful */
92  #define DRBD_SNDBUF_SIZE_MIN  0U
93  #define DRBD_SNDBUF_SIZE_MAX  (10U<<20)
94  #define DRBD_SNDBUF_SIZE_DEF  0U
95  #define DRBD_SNDBUF_SIZE_SCALE '1'
96  
97  #define DRBD_RCVBUF_SIZE_MIN  0U
98  #define DRBD_RCVBUF_SIZE_MAX  (10U<<20)
99  #define DRBD_RCVBUF_SIZE_DEF  0U
100  #define DRBD_RCVBUF_SIZE_SCALE '1'
101  
102    /* @4k PageSize -> 128kB - 512MB */
103  #define DRBD_MAX_BUFFERS_MIN  32U
104  #define DRBD_MAX_BUFFERS_MAX  131072U
105  #define DRBD_MAX_BUFFERS_DEF  2048U
106  #define DRBD_MAX_BUFFERS_SCALE '1'
107  
108    /* @4k PageSize -> 4kB - 512MB */
109  #define DRBD_UNPLUG_WATERMARK_MIN  1U
110  #define DRBD_UNPLUG_WATERMARK_MAX  131072U
111  #define DRBD_UNPLUG_WATERMARK_DEF (DRBD_MAX_BUFFERS_DEF/16)
112  #define DRBD_UNPLUG_WATERMARK_SCALE '1'
113  
114    /* 0 is disabled.
115     * 200 should be more than enough even for very short timeouts */
116  #define DRBD_KO_COUNT_MIN  0U
117  #define DRBD_KO_COUNT_MAX  200U
118  #define DRBD_KO_COUNT_DEF  7U
119  #define DRBD_KO_COUNT_SCALE '1'
120  /* } */
121  
122  /* syncer { */
123    /* FIXME allow rate to be zero? */
124  #define DRBD_RESYNC_RATE_MIN 1U
125  /* channel bonding 10 GbE, or other hardware */
126  #define DRBD_RESYNC_RATE_MAX (4 << 20)
127  #define DRBD_RESYNC_RATE_DEF 250U
128  #define DRBD_RESYNC_RATE_SCALE 'k'  /* kilobytes */
129  
130  #define DRBD_AL_EXTENTS_MIN  67U
131    /* we use u16 as "slot number", (u16)~0 is "FREE".
132     * If you use >= 292 kB on-disk ring buffer,
133     * this is the maximum you can use: */
134  #define DRBD_AL_EXTENTS_MAX  0xfffeU
135  #define DRBD_AL_EXTENTS_DEF  1237U
136  #define DRBD_AL_EXTENTS_SCALE '1'
137  
138  #define DRBD_MINOR_NUMBER_MIN  -1
139  #define DRBD_MINOR_NUMBER_MAX  ((1 << 20) - 1)
140  #define DRBD_MINOR_NUMBER_DEF  -1
141  #define DRBD_MINOR_NUMBER_SCALE '1'
142  
143  /* } */
144  
145  /* drbdsetup XY resize -d Z
146   * you are free to reduce the device size to nothing, if you want to.
147   * the upper limit with 64bit kernel, enough ram and flexible meta data
148   * is 1 PiB, currently. */
149  /* DRBD_MAX_SECTORS */
150  #define DRBD_DISK_SIZE_MIN  0LLU
151  #define DRBD_DISK_SIZE_MAX  (1LLU * (2LLU << 40))
152  #define DRBD_DISK_SIZE_DEF  0LLU /* = disabled = no user size... */
153  #define DRBD_DISK_SIZE_SCALE 's'  /* sectors */
154  
155  #define DRBD_ON_IO_ERROR_DEF EP_DETACH
156  #define DRBD_FENCING_DEF FP_DONT_CARE
157  #define DRBD_AFTER_SB_0P_DEF ASB_DISCONNECT
158  #define DRBD_AFTER_SB_1P_DEF ASB_DISCONNECT
159  #define DRBD_AFTER_SB_2P_DEF ASB_DISCONNECT
160  #define DRBD_RR_CONFLICT_DEF ASB_DISCONNECT
161  #define DRBD_ON_NO_DATA_DEF OND_IO_ERROR
162  #define DRBD_ON_CONGESTION_DEF OC_BLOCK
163  #define DRBD_READ_BALANCING_DEF RB_PREFER_LOCAL
164  
165  #define DRBD_MAX_BIO_BVECS_MIN 0U
166  #define DRBD_MAX_BIO_BVECS_MAX 128U
167  #define DRBD_MAX_BIO_BVECS_DEF 0U
168  #define DRBD_MAX_BIO_BVECS_SCALE '1'
169  
170  #define DRBD_C_PLAN_AHEAD_MIN  0U
171  #define DRBD_C_PLAN_AHEAD_MAX  300U
172  #define DRBD_C_PLAN_AHEAD_DEF  20U
173  #define DRBD_C_PLAN_AHEAD_SCALE '1'
174  
175  #define DRBD_C_DELAY_TARGET_MIN 1U
176  #define DRBD_C_DELAY_TARGET_MAX 100U
177  #define DRBD_C_DELAY_TARGET_DEF 10U
178  #define DRBD_C_DELAY_TARGET_SCALE '1'
179  
180  #define DRBD_C_FILL_TARGET_MIN 0U
181  #define DRBD_C_FILL_TARGET_MAX (1U<<20) /* 500MByte in sec */
182  #define DRBD_C_FILL_TARGET_DEF 100U /* Try to place 50KiB in socket send buffer during resync */
183  #define DRBD_C_FILL_TARGET_SCALE 's'  /* sectors */
184  
185  #define DRBD_C_MAX_RATE_MIN     250U
186  #define DRBD_C_MAX_RATE_MAX     (4U << 20)
187  #define DRBD_C_MAX_RATE_DEF     102400U
188  #define DRBD_C_MAX_RATE_SCALE	'k'  /* kilobytes */
189  
190  #define DRBD_C_MIN_RATE_MIN     0U
191  #define DRBD_C_MIN_RATE_MAX     (4U << 20)
192  #define DRBD_C_MIN_RATE_DEF     250U
193  #define DRBD_C_MIN_RATE_SCALE	'k'  /* kilobytes */
194  
195  #define DRBD_CONG_FILL_MIN	0U
196  #define DRBD_CONG_FILL_MAX	(10U<<21) /* 10GByte in sectors */
197  #define DRBD_CONG_FILL_DEF	0U
198  #define DRBD_CONG_FILL_SCALE	's'  /* sectors */
199  
200  #define DRBD_CONG_EXTENTS_MIN	DRBD_AL_EXTENTS_MIN
201  #define DRBD_CONG_EXTENTS_MAX	DRBD_AL_EXTENTS_MAX
202  #define DRBD_CONG_EXTENTS_DEF	DRBD_AL_EXTENTS_DEF
203  #define DRBD_CONG_EXTENTS_SCALE DRBD_AL_EXTENTS_SCALE
204  
205  #define DRBD_PROTOCOL_DEF DRBD_PROT_C
206  
207  #define DRBD_DISK_BARRIER_DEF	0U
208  #define DRBD_DISK_FLUSHES_DEF	1U
209  #define DRBD_DISK_DRAIN_DEF	1U
210  #define DRBD_MD_FLUSHES_DEF	1U
211  #define DRBD_TCP_CORK_DEF	1U
212  #define DRBD_AL_UPDATES_DEF     1U
213  
214  /* We used to ignore the discard_zeroes_data setting.
215   * To not change established (and expected) behaviour,
216   * by default assume that, for discard_zeroes_data=0,
217   * we can make that an effective discard_zeroes_data=1,
218   * if we only explicitly zero-out unaligned partial chunks. */
219  #define DRBD_DISCARD_ZEROES_IF_ALIGNED_DEF 1U
220  
221  /* Some backends pretend to support WRITE SAME,
222   * but fail such requests when they are actually submitted.
223   * This is to tell DRBD to not even try. */
224  #define DRBD_DISABLE_WRITE_SAME_DEF 0U
225  
226  #define DRBD_ALLOW_TWO_PRIMARIES_DEF	0U
227  #define DRBD_ALWAYS_ASBP_DEF	0U
228  #define DRBD_USE_RLE_DEF	1U
229  #define DRBD_CSUMS_AFTER_CRASH_ONLY_DEF 0U
230  
231  #define DRBD_AL_STRIPES_MIN     1U
232  #define DRBD_AL_STRIPES_MAX     1024U
233  #define DRBD_AL_STRIPES_DEF     1U
234  #define DRBD_AL_STRIPES_SCALE   '1'
235  
236  #define DRBD_AL_STRIPE_SIZE_MIN   4U
237  #define DRBD_AL_STRIPE_SIZE_MAX   16777216U
238  #define DRBD_AL_STRIPE_SIZE_DEF   32U
239  #define DRBD_AL_STRIPE_SIZE_SCALE 'k' /* kilobytes */
240  
241  #define DRBD_SOCKET_CHECK_TIMEO_MIN 0U
242  #define DRBD_SOCKET_CHECK_TIMEO_MAX DRBD_PING_TIMEO_MAX
243  #define DRBD_SOCKET_CHECK_TIMEO_DEF 0U
244  #define DRBD_SOCKET_CHECK_TIMEO_SCALE '1'
245  
246  #define DRBD_RS_DISCARD_GRANULARITY_MIN 0U
247  #define DRBD_RS_DISCARD_GRANULARITY_MAX (1U<<20)  /* 1MiByte */
248  #define DRBD_RS_DISCARD_GRANULARITY_DEF 0U     /* disabled by default */
249  #define DRBD_RS_DISCARD_GRANULARITY_SCALE '1' /* bytes */
250  
251  #endif
252