OpenCloudOS-Kernel/include/linux/drbd_limits.h

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License cleanup: add SPDX GPL-2.0 license identifier to files with no license Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 22:07:57 +08:00
/* SPDX-License-Identifier: GPL-2.0 */
/*
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_MINOR_COUNT_DEF 32
#define DRBD_MINOR_COUNT_SCALE '1'
#define DRBD_VOLUME_MAX 65535
#define DRBD_DIALOG_REFRESH_MIN 0
#define DRBD_DIALOG_REFRESH_MAX 600
#define DRBD_DIALOG_REFRESH_SCALE '1'
/* valid port number */
#define DRBD_PORT_MIN 1
#define DRBD_PORT_MAX 0xffff
#define DRBD_PORT_SCALE '1'
/* 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_WFC_TIMEOUT_SCALE '1'
#define DRBD_DEGR_WFC_TIMEOUT_MIN 0
#define DRBD_DEGR_WFC_TIMEOUT_MAX 300000
#define DRBD_DEGR_WFC_TIMEOUT_DEF 0
#define DRBD_DEGR_WFC_TIMEOUT_SCALE '1'
#define DRBD_OUTDATED_WFC_TIMEOUT_MIN 0
#define DRBD_OUTDATED_WFC_TIMEOUT_MAX 300000
#define DRBD_OUTDATED_WFC_TIMEOUT_DEF 0
#define DRBD_OUTDATED_WFC_TIMEOUT_SCALE '1'
/* }*/
/* net { */
/* timeout, unit centi seconds
* more than one minute timeout is not useful */
#define DRBD_TIMEOUT_MIN 1
#define DRBD_TIMEOUT_MAX 600
#define DRBD_TIMEOUT_DEF 60 /* 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 0 /* 0 = disabled */
#define DRBD_DISK_TIMEOUT_MAX 6000 /* 10 Minutes */
#define DRBD_DISK_TIMEOUT_DEF 0 /* disabled */
#define DRBD_DISK_TIMEOUT_SCALE '1'
/* 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 */
#define DRBD_CONNECT_INT_SCALE '1'
/* keep-alive probes when idle */
#define DRBD_PING_INT_MIN 1
#define DRBD_PING_INT_MAX 120
#define DRBD_PING_INT_DEF 10
#define DRBD_PING_INT_SCALE '1'
/* timeout for the ping packets.*/
#define DRBD_PING_TIMEO_MIN 1
#define DRBD_PING_TIMEO_MAX 300
#define DRBD_PING_TIMEO_DEF 5
#define DRBD_PING_TIMEO_SCALE '1'
/* 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
#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 0
#define DRBD_SNDBUF_SIZE_MAX (10<<20)
#define DRBD_SNDBUF_SIZE_DEF 0
#define DRBD_SNDBUF_SIZE_SCALE '1'
#define DRBD_RCVBUF_SIZE_MIN 0
#define DRBD_RCVBUF_SIZE_MAX (10<<20)
#define DRBD_RCVBUF_SIZE_DEF 0
#define DRBD_RCVBUF_SIZE_SCALE '1'
/* @4k PageSize -> 128kB - 512MB */
#define DRBD_MAX_BUFFERS_MIN 32
#define DRBD_MAX_BUFFERS_MAX 131072
#define DRBD_MAX_BUFFERS_DEF 2048
#define DRBD_MAX_BUFFERS_SCALE '1'
/* @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)
#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 0
#define DRBD_KO_COUNT_MAX 200
#define DRBD_KO_COUNT_DEF 7
#define DRBD_KO_COUNT_SCALE '1'
/* } */
/* syncer { */
/* FIXME allow rate to be zero? */
#define DRBD_RESYNC_RATE_MIN 1
/* channel bonding 10 GbE, or other hardware */
#define DRBD_RESYNC_RATE_MAX (4 << 20)
#define DRBD_RESYNC_RATE_DEF 250
#define DRBD_RESYNC_RATE_SCALE 'k' /* kilobytes */
#define DRBD_AL_EXTENTS_MIN 67
/* 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 0xfffe
#define DRBD_AL_EXTENTS_DEF 1237
#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 0
#define DRBD_DISK_SIZE_MAX (1 * (2LLU << 40))
#define DRBD_DISK_SIZE_DEF 0 /* = 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 0
#define DRBD_MAX_BIO_BVECS_MAX 128
#define DRBD_MAX_BIO_BVECS_DEF 0
#define DRBD_MAX_BIO_BVECS_SCALE '1'
#define DRBD_C_PLAN_AHEAD_MIN 0
#define DRBD_C_PLAN_AHEAD_MAX 300
#define DRBD_C_PLAN_AHEAD_DEF 20
#define DRBD_C_PLAN_AHEAD_SCALE '1'
#define DRBD_C_DELAY_TARGET_MIN 1
#define DRBD_C_DELAY_TARGET_MAX 100
#define DRBD_C_DELAY_TARGET_DEF 10
#define DRBD_C_DELAY_TARGET_SCALE '1'
#define DRBD_C_FILL_TARGET_MIN 0
#define DRBD_C_FILL_TARGET_MAX (1<<20) /* 500MByte in sec */
#define DRBD_C_FILL_TARGET_DEF 100 /* Try to place 50KiB in socket send buffer during resync */
#define DRBD_C_FILL_TARGET_SCALE 's' /* sectors */
#define DRBD_C_MAX_RATE_MIN 250
#define DRBD_C_MAX_RATE_MAX (4 << 20)
#define DRBD_C_MAX_RATE_DEF 102400
#define DRBD_C_MAX_RATE_SCALE 'k' /* kilobytes */
#define DRBD_C_MIN_RATE_MIN 0
#define DRBD_C_MIN_RATE_MAX (4 << 20)
#define DRBD_C_MIN_RATE_DEF 250
#define DRBD_C_MIN_RATE_SCALE 'k' /* kilobytes */
#define DRBD_CONG_FILL_MIN 0
#define DRBD_CONG_FILL_MAX (10<<21) /* 10GByte in sectors */
#define DRBD_CONG_FILL_DEF 0
#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 0
#define DRBD_DISK_FLUSHES_DEF 1
#define DRBD_DISK_DRAIN_DEF 1
#define DRBD_MD_FLUSHES_DEF 1
#define DRBD_TCP_CORK_DEF 1
#define DRBD_AL_UPDATES_DEF 1
drbd: when receiving P_TRIM, zero-out partial unaligned chunks We can avoid spurious data divergence caused by partially-ignored discards on certain backends with discard_zeroes_data=0, if we translate partial unaligned discard requests into explicit zero-out. The relevant use case is LVM/DM thin. If on different nodes, DRBD is backed by devices with differing discard characteristics, discards may lead to data divergence (old data or garbage left over on one backend, zeroes due to unmapped areas on the other backend). Online verify would now potentially report tons of spurious differences. While probably harmless for most use cases (fstrim on a file system), DRBD cannot have that, it would violate our promise to upper layers that our data instances on the nodes are identical. To be correct and play safe (make sure data is identical on both copies), we would have to disable discard support, if our local backend (on a Primary) does not support "discard_zeroes_data=true". We'd also have to translate discards to explicit zero-out on the receiving (typically: Secondary) side, unless the receiving side supports "discard_zeroes_data=true". Which both would allocate those blocks, instead of unmapping them, in contrast with expectations. LVM/DM thin does set discard_zeroes_data=0, because it silently ignores discards to partial chunks. We can work around this by checking the alignment first. For unaligned (wrt. alignment and granularity) or too small discards, we zero-out the initial (and/or) trailing unaligned partial chunks, but discard all the aligned full chunks. At least for LVM/DM thin, the result is effectively "discard_zeroes_data=1". Arguably it should behave this way internally, by default, and we'll try to make that happen. But our workaround is still valid for already deployed setups, and for other devices that may behave this way. Setting discard-zeroes-if-aligned=yes will allow DRBD to use discards, and to announce discard_zeroes_data=true, even on backends that announce discard_zeroes_data=false. Setting discard-zeroes-if-aligned=no will cause DRBD to always fall-back to zero-out on the receiving side, and to not even announce discard capabilities on the Primary, if the respective backend announces discard_zeroes_data=false. We used to ignore the discard_zeroes_data setting completely. To not break established and expected behaviour, and suddenly cause fstrim on thin-provisioned LVs to run out-of-space, instead of freeing up space, the default value is "yes". Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-06-14 06:26:20 +08:00
/* 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 1
/* 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 0
#define DRBD_ALLOW_TWO_PRIMARIES_DEF 0
#define DRBD_ALWAYS_ASBP_DEF 0
#define DRBD_USE_RLE_DEF 1
#define DRBD_CSUMS_AFTER_CRASH_ONLY_DEF 0
#define DRBD_AL_STRIPES_MIN 1
#define DRBD_AL_STRIPES_MAX 1024
#define DRBD_AL_STRIPES_DEF 1
#define DRBD_AL_STRIPES_SCALE '1'
#define DRBD_AL_STRIPE_SIZE_MIN 4
#define DRBD_AL_STRIPE_SIZE_MAX 16777216
#define DRBD_AL_STRIPE_SIZE_DEF 32
#define DRBD_AL_STRIPE_SIZE_SCALE 'k' /* kilobytes */
#define DRBD_SOCKET_CHECK_TIMEO_MIN 0
#define DRBD_SOCKET_CHECK_TIMEO_MAX DRBD_PING_TIMEO_MAX
#define DRBD_SOCKET_CHECK_TIMEO_DEF 0
#define DRBD_SOCKET_CHECK_TIMEO_SCALE '1'
#define DRBD_RS_DISCARD_GRANULARITY_MIN 0
#define DRBD_RS_DISCARD_GRANULARITY_MAX (1<<20) /* 1MiByte */
#define DRBD_RS_DISCARD_GRANULARITY_DEF 0 /* disabled by default */
#define DRBD_RS_DISCARD_GRANULARITY_SCALE '1' /* bytes */
#endif