/* SPDX-License-Identifier: GPL-2.0-only WITH Linux-syscall-note *//*  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 _UAPI_LINUX_DRBD_LIMITS_H#define _UAPI_LINUX_DRBD_LIMITS_H #include <linux/drbd.h> #define DRBD_MINOR_COUNT_MIN 1U#define DRBD_MINOR_COUNT_MAX 255U#define DRBD_MINOR_COUNT_DEF 32U#define DRBD_MINOR_COUNT_SCALE '1' #define DRBD_VOLUME_MAX 65534U #define DRBD_DIALOG_REFRESH_MIN 0U#define DRBD_DIALOG_REFRESH_MAX 600U#define DRBD_DIALOG_REFRESH_SCALE '1' /* valid port number */#define DRBD_PORT_MIN 1U#define DRBD_PORT_MAX 0xffffU#define DRBD_PORT_SCALE '1' /* startup { */  /* if you want more than 3.4 days, disable */#define DRBD_WFC_TIMEOUT_MIN 0U#define DRBD_WFC_TIMEOUT_MAX 300000U#define DRBD_WFC_TIMEOUT_DEF 0U#define DRBD_WFC_TIMEOUT_SCALE '1' #define DRBD_DEGR_WFC_TIMEOUT_MIN 0U#define DRBD_DEGR_WFC_TIMEOUT_MAX 300000U#define DRBD_DEGR_WFC_TIMEOUT_DEF 0U#define DRBD_DEGR_WFC_TIMEOUT_SCALE '1' #define DRBD_OUTDATED_WFC_TIMEOUT_MIN 0U#define DRBD_OUTDATED_WFC_TIMEOUT_MAX 300000U#define DRBD_OUTDATED_WFC_TIMEOUT_DEF 0U#define DRBD_OUTDATED_WFC_TIMEOUT_SCALE '1'/* }*/ /* net { */  /* timeout, unit centi seconds   * more than one minute timeout is not useful */#define DRBD_TIMEOUT_MIN 1U#define DRBD_TIMEOUT_MAX 600U#define DRBD_TIMEOUT_DEF 60U       /* 6 seconds */#define DRBD_TIMEOUT_SCALE '1'  /* If backing disk takes longer than disk_timeout, mark the disk as failed */#define DRBD_DISK_TIMEOUT_MIN 0U    /* 0 = disabled */#define DRBD_DISK_TIMEOUT_MAX 6000U /* 10 Minutes */#define DRBD_DISK_TIMEOUT_DEF 0U    /* disabled */#define DRBD_DISK_TIMEOUT_SCALE '1'   /* active connection retries when C_WF_CONNECTION */#define DRBD_CONNECT_INT_MIN 1U#define DRBD_CONNECT_INT_MAX 120U#define DRBD_CONNECT_INT_DEF 10U   /* seconds */#define DRBD_CONNECT_INT_SCALE '1'   /* keep-alive probes when idle */#define DRBD_PING_INT_MIN 1U#define DRBD_PING_INT_MAX 120U#define DRBD_PING_INT_DEF 10U#define DRBD_PING_INT_SCALE '1'  /* timeout for the ping packets.*/#define DRBD_PING_TIMEO_MIN  1U#define DRBD_PING_TIMEO_MAX  300U#define DRBD_PING_TIMEO_DEF  5U#define DRBD_PING_TIMEO_SCALE '1'   /* max number of write requests between write barriers */#define DRBD_MAX_EPOCH_SIZE_MIN 1U#define DRBD_MAX_EPOCH_SIZE_MAX 20000U#define DRBD_MAX_EPOCH_SIZE_DEF 2048U#define DRBD_MAX_EPOCH_SIZE_SCALE '1'   /* I don't think that a tcp send buffer of more than 10M is useful */#define DRBD_SNDBUF_SIZE_MIN  0U#define DRBD_SNDBUF_SIZE_MAX  (10U<<20)#define DRBD_SNDBUF_SIZE_DEF  0U#define DRBD_SNDBUF_SIZE_SCALE '1' #define DRBD_RCVBUF_SIZE_MIN  0U#define DRBD_RCVBUF_SIZE_MAX  (10U<<20)#define DRBD_RCVBUF_SIZE_DEF  0U#define DRBD_RCVBUF_SIZE_SCALE '1'   /* @4k PageSize -> 128kB - 512MB */#define DRBD_MAX_BUFFERS_MIN  32U#define DRBD_MAX_BUFFERS_MAX  131072U#define DRBD_MAX_BUFFERS_DEF  2048U#define DRBD_MAX_BUFFERS_SCALE '1'   /* @4k PageSize -> 4kB - 512MB */#define DRBD_UNPLUG_WATERMARK_MIN  1U#define DRBD_UNPLUG_WATERMARK_MAX  131072U#define DRBD_UNPLUG_WATERMARK_DEF (DRBD_MAX_BUFFERS_DEF/16)#define DRBD_UNPLUG_WATERMARK_SCALE '1'   /* 0 is disabled.   * 200 should be more than enough even for very short timeouts */#define DRBD_KO_COUNT_MIN  0U#define DRBD_KO_COUNT_MAX  200U#define DRBD_KO_COUNT_DEF  7U#define DRBD_KO_COUNT_SCALE '1'/* } */ /* syncer { */  /* FIXME allow rate to be zero? */#define DRBD_RESYNC_RATE_MIN 1U/* channel bonding 10 GbE, or other hardware */#define DRBD_RESYNC_RATE_MAX (4 << 20)#define DRBD_RESYNC_RATE_DEF 250U#define DRBD_RESYNC_RATE_SCALE 'k'  /* kilobytes */ #define DRBD_AL_EXTENTS_MIN  67U  /* we use u16 as "slot number", (u16)~0 is "FREE".   * If you use >= 292 kB on-disk ring buffer,   * this is the maximum you can use: */#define DRBD_AL_EXTENTS_MAX  0xfffeU#define DRBD_AL_EXTENTS_DEF  1237U#define DRBD_AL_EXTENTS_SCALE '1' #define DRBD_MINOR_NUMBER_MIN  -1#define DRBD_MINOR_NUMBER_MAX  ((1 << 20) - 1)#define DRBD_MINOR_NUMBER_DEF  -1#define DRBD_MINOR_NUMBER_SCALE '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 1 PiB, currently. *//* DRBD_MAX_SECTORS */#define DRBD_DISK_SIZE_MIN  0LLU#define DRBD_DISK_SIZE_MAX  (1LLU * (2LLU << 40))#define DRBD_DISK_SIZE_DEF  0LLU /* = disabled = no user size... */#define DRBD_DISK_SIZE_SCALE 's'  /* sectors */ #define DRBD_ON_IO_ERROR_DEF EP_DETACH#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_ON_NO_DATA_DEF OND_IO_ERROR#define DRBD_ON_CONGESTION_DEF OC_BLOCK#define DRBD_READ_BALANCING_DEF RB_PREFER_LOCAL #define DRBD_MAX_BIO_BVECS_MIN 0U#define DRBD_MAX_BIO_BVECS_MAX 128U#define DRBD_MAX_BIO_BVECS_DEF 0U#define DRBD_MAX_BIO_BVECS_SCALE '1' #define DRBD_C_PLAN_AHEAD_MIN  0U#define DRBD_C_PLAN_AHEAD_MAX  300U#define DRBD_C_PLAN_AHEAD_DEF  20U#define DRBD_C_PLAN_AHEAD_SCALE '1' #define DRBD_C_DELAY_TARGET_MIN 1U#define DRBD_C_DELAY_TARGET_MAX 100U#define DRBD_C_DELAY_TARGET_DEF 10U#define DRBD_C_DELAY_TARGET_SCALE '1' #define DRBD_C_FILL_TARGET_MIN 0U#define DRBD_C_FILL_TARGET_MAX (1U<<20) /* 500MByte in sec */#define DRBD_C_FILL_TARGET_DEF 100U /* Try to place 50KiB in socket send buffer during resync */#define DRBD_C_FILL_TARGET_SCALE 's'  /* sectors */ #define DRBD_C_MAX_RATE_MIN     250U#define DRBD_C_MAX_RATE_MAX     (4U << 20)#define DRBD_C_MAX_RATE_DEF     102400U#define DRBD_C_MAX_RATE_SCALE	'k'  /* kilobytes */ #define DRBD_C_MIN_RATE_MIN     0U#define DRBD_C_MIN_RATE_MAX     (4U << 20)#define DRBD_C_MIN_RATE_DEF     250U#define DRBD_C_MIN_RATE_SCALE	'k'  /* kilobytes */ #define DRBD_CONG_FILL_MIN	0U#define DRBD_CONG_FILL_MAX	(10U<<21) /* 10GByte in sectors */#define DRBD_CONG_FILL_DEF	0U#define DRBD_CONG_FILL_SCALE	's'  /* sectors */ #define DRBD_CONG_EXTENTS_MIN	DRBD_AL_EXTENTS_MIN#define DRBD_CONG_EXTENTS_MAX	DRBD_AL_EXTENTS_MAX#define DRBD_CONG_EXTENTS_DEF	DRBD_AL_EXTENTS_DEF#define DRBD_CONG_EXTENTS_SCALE DRBD_AL_EXTENTS_SCALE #define DRBD_PROTOCOL_DEF DRBD_PROT_C #define DRBD_DISK_BARRIER_DEF	0U#define DRBD_DISK_FLUSHES_DEF	1U#define DRBD_DISK_DRAIN_DEF	1U#define DRBD_MD_FLUSHES_DEF	1U#define DRBD_TCP_CORK_DEF	1U#define DRBD_AL_UPDATES_DEF     1U /* We used to ignore the discard_zeroes_data setting. * To not change established (and expected) behaviour, * by default assume that, for discard_zeroes_data=0, * we can make that an effective discard_zeroes_data=1, * if we only explicitly zero-out unaligned partial chunks. */#define DRBD_DISCARD_ZEROES_IF_ALIGNED_DEF 1U /* Some backends pretend to support WRITE SAME, * but fail such requests when they are actually submitted. * This is to tell DRBD to not even try. */#define DRBD_DISABLE_WRITE_SAME_DEF 0U #define DRBD_ALLOW_TWO_PRIMARIES_DEF	0U#define DRBD_ALWAYS_ASBP_DEF	0U#define DRBD_USE_RLE_DEF	1U#define DRBD_CSUMS_AFTER_CRASH_ONLY_DEF 0U #define DRBD_AL_STRIPES_MIN     1U#define DRBD_AL_STRIPES_MAX     1024U#define DRBD_AL_STRIPES_DEF     1U#define DRBD_AL_STRIPES_SCALE   '1' #define DRBD_AL_STRIPE_SIZE_MIN   4U#define DRBD_AL_STRIPE_SIZE_MAX   16777216U#define DRBD_AL_STRIPE_SIZE_DEF   32U#define DRBD_AL_STRIPE_SIZE_SCALE 'k' /* kilobytes */ #define DRBD_SOCKET_CHECK_TIMEO_MIN 0U#define DRBD_SOCKET_CHECK_TIMEO_MAX DRBD_PING_TIMEO_MAX#define DRBD_SOCKET_CHECK_TIMEO_DEF 0U#define DRBD_SOCKET_CHECK_TIMEO_SCALE '1' #define DRBD_RS_DISCARD_GRANULARITY_MIN 0U#define DRBD_RS_DISCARD_GRANULARITY_MAX (1U<<20)  /* 1MiByte */#define DRBD_RS_DISCARD_GRANULARITY_DEF 0U     /* disabled by default */#define DRBD_RS_DISCARD_GRANULARITY_SCALE '1' /* bytes */ #endif /* _UAPI_LINUX_DRBD_LIMITS_H */