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![Greg Kroah-Hartman](/assets/img/avatar_default.png)
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>
615 lines
16 KiB
C
615 lines
16 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* Request reply cache. This is currently a global cache, but this may
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* change in the future and be a per-client cache.
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*
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* This code is heavily inspired by the 44BSD implementation, although
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* it does things a bit differently.
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*
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* Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
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*/
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#include <linux/slab.h>
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#include <linux/vmalloc.h>
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#include <linux/sunrpc/addr.h>
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#include <linux/highmem.h>
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#include <linux/log2.h>
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#include <linux/hash.h>
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#include <net/checksum.h>
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#include "nfsd.h"
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#include "cache.h"
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#define NFSDDBG_FACILITY NFSDDBG_REPCACHE
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/*
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* We use this value to determine the number of hash buckets from the max
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* cache size, the idea being that when the cache is at its maximum number
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* of entries, then this should be the average number of entries per bucket.
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*/
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#define TARGET_BUCKET_SIZE 64
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struct nfsd_drc_bucket {
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struct list_head lru_head;
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spinlock_t cache_lock;
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};
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static struct nfsd_drc_bucket *drc_hashtbl;
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static struct kmem_cache *drc_slab;
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/* max number of entries allowed in the cache */
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static unsigned int max_drc_entries;
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/* number of significant bits in the hash value */
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static unsigned int maskbits;
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static unsigned int drc_hashsize;
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/*
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* Stats and other tracking of on the duplicate reply cache. All of these and
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* the "rc" fields in nfsdstats are protected by the cache_lock
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*/
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/* total number of entries */
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static atomic_t num_drc_entries;
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/* cache misses due only to checksum comparison failures */
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static unsigned int payload_misses;
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/* amount of memory (in bytes) currently consumed by the DRC */
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static unsigned int drc_mem_usage;
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/* longest hash chain seen */
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static unsigned int longest_chain;
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/* size of cache when we saw the longest hash chain */
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static unsigned int longest_chain_cachesize;
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static int nfsd_cache_append(struct svc_rqst *rqstp, struct kvec *vec);
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static unsigned long nfsd_reply_cache_count(struct shrinker *shrink,
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struct shrink_control *sc);
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static unsigned long nfsd_reply_cache_scan(struct shrinker *shrink,
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struct shrink_control *sc);
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static struct shrinker nfsd_reply_cache_shrinker = {
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.scan_objects = nfsd_reply_cache_scan,
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.count_objects = nfsd_reply_cache_count,
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.seeks = 1,
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};
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/*
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* Put a cap on the size of the DRC based on the amount of available
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* low memory in the machine.
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*
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* 64MB: 8192
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* 128MB: 11585
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* 256MB: 16384
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* 512MB: 23170
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* 1GB: 32768
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* 2GB: 46340
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* 4GB: 65536
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* 8GB: 92681
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* 16GB: 131072
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*
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* ...with a hard cap of 256k entries. In the worst case, each entry will be
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* ~1k, so the above numbers should give a rough max of the amount of memory
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* used in k.
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*/
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static unsigned int
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nfsd_cache_size_limit(void)
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{
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unsigned int limit;
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unsigned long low_pages = totalram_pages - totalhigh_pages;
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limit = (16 * int_sqrt(low_pages)) << (PAGE_SHIFT-10);
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return min_t(unsigned int, limit, 256*1024);
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}
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/*
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* Compute the number of hash buckets we need. Divide the max cachesize by
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* the "target" max bucket size, and round up to next power of two.
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*/
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static unsigned int
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nfsd_hashsize(unsigned int limit)
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{
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return roundup_pow_of_two(limit / TARGET_BUCKET_SIZE);
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}
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static u32
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nfsd_cache_hash(__be32 xid)
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{
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return hash_32(be32_to_cpu(xid), maskbits);
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}
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static struct svc_cacherep *
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nfsd_reply_cache_alloc(void)
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{
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struct svc_cacherep *rp;
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rp = kmem_cache_alloc(drc_slab, GFP_KERNEL);
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if (rp) {
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rp->c_state = RC_UNUSED;
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rp->c_type = RC_NOCACHE;
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INIT_LIST_HEAD(&rp->c_lru);
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}
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return rp;
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}
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static void
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nfsd_reply_cache_free_locked(struct svc_cacherep *rp)
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{
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if (rp->c_type == RC_REPLBUFF && rp->c_replvec.iov_base) {
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drc_mem_usage -= rp->c_replvec.iov_len;
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kfree(rp->c_replvec.iov_base);
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}
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list_del(&rp->c_lru);
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atomic_dec(&num_drc_entries);
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drc_mem_usage -= sizeof(*rp);
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kmem_cache_free(drc_slab, rp);
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}
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static void
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nfsd_reply_cache_free(struct nfsd_drc_bucket *b, struct svc_cacherep *rp)
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{
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spin_lock(&b->cache_lock);
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nfsd_reply_cache_free_locked(rp);
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spin_unlock(&b->cache_lock);
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}
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int nfsd_reply_cache_init(void)
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{
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unsigned int hashsize;
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unsigned int i;
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int status = 0;
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max_drc_entries = nfsd_cache_size_limit();
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atomic_set(&num_drc_entries, 0);
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hashsize = nfsd_hashsize(max_drc_entries);
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maskbits = ilog2(hashsize);
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status = register_shrinker(&nfsd_reply_cache_shrinker);
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if (status)
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return status;
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drc_slab = kmem_cache_create("nfsd_drc", sizeof(struct svc_cacherep),
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0, 0, NULL);
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if (!drc_slab)
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goto out_nomem;
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drc_hashtbl = kcalloc(hashsize, sizeof(*drc_hashtbl), GFP_KERNEL);
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if (!drc_hashtbl) {
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drc_hashtbl = vzalloc(hashsize * sizeof(*drc_hashtbl));
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if (!drc_hashtbl)
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goto out_nomem;
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}
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for (i = 0; i < hashsize; i++) {
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INIT_LIST_HEAD(&drc_hashtbl[i].lru_head);
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spin_lock_init(&drc_hashtbl[i].cache_lock);
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}
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drc_hashsize = hashsize;
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return 0;
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out_nomem:
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printk(KERN_ERR "nfsd: failed to allocate reply cache\n");
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nfsd_reply_cache_shutdown();
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return -ENOMEM;
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}
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void nfsd_reply_cache_shutdown(void)
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{
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struct svc_cacherep *rp;
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unsigned int i;
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unregister_shrinker(&nfsd_reply_cache_shrinker);
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for (i = 0; i < drc_hashsize; i++) {
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struct list_head *head = &drc_hashtbl[i].lru_head;
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while (!list_empty(head)) {
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rp = list_first_entry(head, struct svc_cacherep, c_lru);
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nfsd_reply_cache_free_locked(rp);
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}
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}
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kvfree(drc_hashtbl);
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drc_hashtbl = NULL;
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drc_hashsize = 0;
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kmem_cache_destroy(drc_slab);
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drc_slab = NULL;
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}
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/*
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* Move cache entry to end of LRU list, and queue the cleaner to run if it's
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* not already scheduled.
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*/
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static void
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lru_put_end(struct nfsd_drc_bucket *b, struct svc_cacherep *rp)
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{
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rp->c_timestamp = jiffies;
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list_move_tail(&rp->c_lru, &b->lru_head);
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}
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static long
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prune_bucket(struct nfsd_drc_bucket *b)
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{
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struct svc_cacherep *rp, *tmp;
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long freed = 0;
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list_for_each_entry_safe(rp, tmp, &b->lru_head, c_lru) {
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/*
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* Don't free entries attached to calls that are still
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* in-progress, but do keep scanning the list.
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*/
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if (rp->c_state == RC_INPROG)
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continue;
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if (atomic_read(&num_drc_entries) <= max_drc_entries &&
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time_before(jiffies, rp->c_timestamp + RC_EXPIRE))
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break;
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nfsd_reply_cache_free_locked(rp);
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freed++;
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}
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return freed;
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}
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/*
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* Walk the LRU list and prune off entries that are older than RC_EXPIRE.
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* Also prune the oldest ones when the total exceeds the max number of entries.
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*/
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static long
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prune_cache_entries(void)
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{
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unsigned int i;
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long freed = 0;
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for (i = 0; i < drc_hashsize; i++) {
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struct nfsd_drc_bucket *b = &drc_hashtbl[i];
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if (list_empty(&b->lru_head))
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continue;
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spin_lock(&b->cache_lock);
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freed += prune_bucket(b);
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spin_unlock(&b->cache_lock);
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}
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return freed;
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}
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static unsigned long
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nfsd_reply_cache_count(struct shrinker *shrink, struct shrink_control *sc)
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{
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return atomic_read(&num_drc_entries);
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}
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static unsigned long
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nfsd_reply_cache_scan(struct shrinker *shrink, struct shrink_control *sc)
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{
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return prune_cache_entries();
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}
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/*
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* Walk an xdr_buf and get a CRC for at most the first RC_CSUMLEN bytes
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*/
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static __wsum
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nfsd_cache_csum(struct svc_rqst *rqstp)
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{
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int idx;
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unsigned int base;
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__wsum csum;
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struct xdr_buf *buf = &rqstp->rq_arg;
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const unsigned char *p = buf->head[0].iov_base;
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size_t csum_len = min_t(size_t, buf->head[0].iov_len + buf->page_len,
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RC_CSUMLEN);
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size_t len = min(buf->head[0].iov_len, csum_len);
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/* rq_arg.head first */
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csum = csum_partial(p, len, 0);
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csum_len -= len;
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/* Continue into page array */
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idx = buf->page_base / PAGE_SIZE;
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base = buf->page_base & ~PAGE_MASK;
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while (csum_len) {
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p = page_address(buf->pages[idx]) + base;
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len = min_t(size_t, PAGE_SIZE - base, csum_len);
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csum = csum_partial(p, len, csum);
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csum_len -= len;
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base = 0;
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++idx;
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}
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return csum;
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}
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static bool
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nfsd_cache_match(struct svc_rqst *rqstp, __wsum csum, struct svc_cacherep *rp)
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{
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/* Check RPC XID first */
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if (rqstp->rq_xid != rp->c_xid)
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return false;
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/* compare checksum of NFS data */
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if (csum != rp->c_csum) {
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++payload_misses;
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return false;
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}
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/* Other discriminators */
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if (rqstp->rq_proc != rp->c_proc ||
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rqstp->rq_prot != rp->c_prot ||
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rqstp->rq_vers != rp->c_vers ||
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rqstp->rq_arg.len != rp->c_len ||
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!rpc_cmp_addr(svc_addr(rqstp), (struct sockaddr *)&rp->c_addr) ||
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rpc_get_port(svc_addr(rqstp)) != rpc_get_port((struct sockaddr *)&rp->c_addr))
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return false;
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return true;
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}
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/*
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* Search the request hash for an entry that matches the given rqstp.
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* Must be called with cache_lock held. Returns the found entry or
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* NULL on failure.
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*/
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static struct svc_cacherep *
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nfsd_cache_search(struct nfsd_drc_bucket *b, struct svc_rqst *rqstp,
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__wsum csum)
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{
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struct svc_cacherep *rp, *ret = NULL;
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struct list_head *rh = &b->lru_head;
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unsigned int entries = 0;
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list_for_each_entry(rp, rh, c_lru) {
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++entries;
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if (nfsd_cache_match(rqstp, csum, rp)) {
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ret = rp;
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break;
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}
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}
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/* tally hash chain length stats */
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if (entries > longest_chain) {
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longest_chain = entries;
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longest_chain_cachesize = atomic_read(&num_drc_entries);
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} else if (entries == longest_chain) {
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/* prefer to keep the smallest cachesize possible here */
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longest_chain_cachesize = min_t(unsigned int,
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longest_chain_cachesize,
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atomic_read(&num_drc_entries));
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}
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return ret;
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}
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/*
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* Try to find an entry matching the current call in the cache. When none
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* is found, we try to grab the oldest expired entry off the LRU list. If
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* a suitable one isn't there, then drop the cache_lock and allocate a
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* new one, then search again in case one got inserted while this thread
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* didn't hold the lock.
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*/
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int
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nfsd_cache_lookup(struct svc_rqst *rqstp)
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{
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struct svc_cacherep *rp, *found;
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__be32 xid = rqstp->rq_xid;
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u32 proto = rqstp->rq_prot,
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vers = rqstp->rq_vers,
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proc = rqstp->rq_proc;
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__wsum csum;
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u32 hash = nfsd_cache_hash(xid);
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struct nfsd_drc_bucket *b = &drc_hashtbl[hash];
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unsigned long age;
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int type = rqstp->rq_cachetype;
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int rtn = RC_DOIT;
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rqstp->rq_cacherep = NULL;
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if (type == RC_NOCACHE) {
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nfsdstats.rcnocache++;
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return rtn;
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}
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csum = nfsd_cache_csum(rqstp);
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/*
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* Since the common case is a cache miss followed by an insert,
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* preallocate an entry.
|
|
*/
|
|
rp = nfsd_reply_cache_alloc();
|
|
spin_lock(&b->cache_lock);
|
|
if (likely(rp)) {
|
|
atomic_inc(&num_drc_entries);
|
|
drc_mem_usage += sizeof(*rp);
|
|
}
|
|
|
|
/* go ahead and prune the cache */
|
|
prune_bucket(b);
|
|
|
|
found = nfsd_cache_search(b, rqstp, csum);
|
|
if (found) {
|
|
if (likely(rp))
|
|
nfsd_reply_cache_free_locked(rp);
|
|
rp = found;
|
|
goto found_entry;
|
|
}
|
|
|
|
if (!rp) {
|
|
dprintk("nfsd: unable to allocate DRC entry!\n");
|
|
goto out;
|
|
}
|
|
|
|
nfsdstats.rcmisses++;
|
|
rqstp->rq_cacherep = rp;
|
|
rp->c_state = RC_INPROG;
|
|
rp->c_xid = xid;
|
|
rp->c_proc = proc;
|
|
rpc_copy_addr((struct sockaddr *)&rp->c_addr, svc_addr(rqstp));
|
|
rpc_set_port((struct sockaddr *)&rp->c_addr, rpc_get_port(svc_addr(rqstp)));
|
|
rp->c_prot = proto;
|
|
rp->c_vers = vers;
|
|
rp->c_len = rqstp->rq_arg.len;
|
|
rp->c_csum = csum;
|
|
|
|
lru_put_end(b, rp);
|
|
|
|
/* release any buffer */
|
|
if (rp->c_type == RC_REPLBUFF) {
|
|
drc_mem_usage -= rp->c_replvec.iov_len;
|
|
kfree(rp->c_replvec.iov_base);
|
|
rp->c_replvec.iov_base = NULL;
|
|
}
|
|
rp->c_type = RC_NOCACHE;
|
|
out:
|
|
spin_unlock(&b->cache_lock);
|
|
return rtn;
|
|
|
|
found_entry:
|
|
nfsdstats.rchits++;
|
|
/* We found a matching entry which is either in progress or done. */
|
|
age = jiffies - rp->c_timestamp;
|
|
lru_put_end(b, rp);
|
|
|
|
rtn = RC_DROPIT;
|
|
/* Request being processed or excessive rexmits */
|
|
if (rp->c_state == RC_INPROG || age < RC_DELAY)
|
|
goto out;
|
|
|
|
/* From the hall of fame of impractical attacks:
|
|
* Is this a user who tries to snoop on the cache? */
|
|
rtn = RC_DOIT;
|
|
if (!test_bit(RQ_SECURE, &rqstp->rq_flags) && rp->c_secure)
|
|
goto out;
|
|
|
|
/* Compose RPC reply header */
|
|
switch (rp->c_type) {
|
|
case RC_NOCACHE:
|
|
break;
|
|
case RC_REPLSTAT:
|
|
svc_putu32(&rqstp->rq_res.head[0], rp->c_replstat);
|
|
rtn = RC_REPLY;
|
|
break;
|
|
case RC_REPLBUFF:
|
|
if (!nfsd_cache_append(rqstp, &rp->c_replvec))
|
|
goto out; /* should not happen */
|
|
rtn = RC_REPLY;
|
|
break;
|
|
default:
|
|
printk(KERN_WARNING "nfsd: bad repcache type %d\n", rp->c_type);
|
|
nfsd_reply_cache_free_locked(rp);
|
|
}
|
|
|
|
goto out;
|
|
}
|
|
|
|
/*
|
|
* Update a cache entry. This is called from nfsd_dispatch when
|
|
* the procedure has been executed and the complete reply is in
|
|
* rqstp->rq_res.
|
|
*
|
|
* We're copying around data here rather than swapping buffers because
|
|
* the toplevel loop requires max-sized buffers, which would be a waste
|
|
* of memory for a cache with a max reply size of 100 bytes (diropokres).
|
|
*
|
|
* If we should start to use different types of cache entries tailored
|
|
* specifically for attrstat and fh's, we may save even more space.
|
|
*
|
|
* Also note that a cachetype of RC_NOCACHE can legally be passed when
|
|
* nfsd failed to encode a reply that otherwise would have been cached.
|
|
* In this case, nfsd_cache_update is called with statp == NULL.
|
|
*/
|
|
void
|
|
nfsd_cache_update(struct svc_rqst *rqstp, int cachetype, __be32 *statp)
|
|
{
|
|
struct svc_cacherep *rp = rqstp->rq_cacherep;
|
|
struct kvec *resv = &rqstp->rq_res.head[0], *cachv;
|
|
u32 hash;
|
|
struct nfsd_drc_bucket *b;
|
|
int len;
|
|
size_t bufsize = 0;
|
|
|
|
if (!rp)
|
|
return;
|
|
|
|
hash = nfsd_cache_hash(rp->c_xid);
|
|
b = &drc_hashtbl[hash];
|
|
|
|
len = resv->iov_len - ((char*)statp - (char*)resv->iov_base);
|
|
len >>= 2;
|
|
|
|
/* Don't cache excessive amounts of data and XDR failures */
|
|
if (!statp || len > (256 >> 2)) {
|
|
nfsd_reply_cache_free(b, rp);
|
|
return;
|
|
}
|
|
|
|
switch (cachetype) {
|
|
case RC_REPLSTAT:
|
|
if (len != 1)
|
|
printk("nfsd: RC_REPLSTAT/reply len %d!\n",len);
|
|
rp->c_replstat = *statp;
|
|
break;
|
|
case RC_REPLBUFF:
|
|
cachv = &rp->c_replvec;
|
|
bufsize = len << 2;
|
|
cachv->iov_base = kmalloc(bufsize, GFP_KERNEL);
|
|
if (!cachv->iov_base) {
|
|
nfsd_reply_cache_free(b, rp);
|
|
return;
|
|
}
|
|
cachv->iov_len = bufsize;
|
|
memcpy(cachv->iov_base, statp, bufsize);
|
|
break;
|
|
case RC_NOCACHE:
|
|
nfsd_reply_cache_free(b, rp);
|
|
return;
|
|
}
|
|
spin_lock(&b->cache_lock);
|
|
drc_mem_usage += bufsize;
|
|
lru_put_end(b, rp);
|
|
rp->c_secure = test_bit(RQ_SECURE, &rqstp->rq_flags);
|
|
rp->c_type = cachetype;
|
|
rp->c_state = RC_DONE;
|
|
spin_unlock(&b->cache_lock);
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Copy cached reply to current reply buffer. Should always fit.
|
|
* FIXME as reply is in a page, we should just attach the page, and
|
|
* keep a refcount....
|
|
*/
|
|
static int
|
|
nfsd_cache_append(struct svc_rqst *rqstp, struct kvec *data)
|
|
{
|
|
struct kvec *vec = &rqstp->rq_res.head[0];
|
|
|
|
if (vec->iov_len + data->iov_len > PAGE_SIZE) {
|
|
printk(KERN_WARNING "nfsd: cached reply too large (%zd).\n",
|
|
data->iov_len);
|
|
return 0;
|
|
}
|
|
memcpy((char*)vec->iov_base + vec->iov_len, data->iov_base, data->iov_len);
|
|
vec->iov_len += data->iov_len;
|
|
return 1;
|
|
}
|
|
|
|
/*
|
|
* Note that fields may be added, removed or reordered in the future. Programs
|
|
* scraping this file for info should test the labels to ensure they're
|
|
* getting the correct field.
|
|
*/
|
|
static int nfsd_reply_cache_stats_show(struct seq_file *m, void *v)
|
|
{
|
|
seq_printf(m, "max entries: %u\n", max_drc_entries);
|
|
seq_printf(m, "num entries: %u\n",
|
|
atomic_read(&num_drc_entries));
|
|
seq_printf(m, "hash buckets: %u\n", 1 << maskbits);
|
|
seq_printf(m, "mem usage: %u\n", drc_mem_usage);
|
|
seq_printf(m, "cache hits: %u\n", nfsdstats.rchits);
|
|
seq_printf(m, "cache misses: %u\n", nfsdstats.rcmisses);
|
|
seq_printf(m, "not cached: %u\n", nfsdstats.rcnocache);
|
|
seq_printf(m, "payload misses: %u\n", payload_misses);
|
|
seq_printf(m, "longest chain len: %u\n", longest_chain);
|
|
seq_printf(m, "cachesize at longest: %u\n", longest_chain_cachesize);
|
|
return 0;
|
|
}
|
|
|
|
int nfsd_reply_cache_stats_open(struct inode *inode, struct file *file)
|
|
{
|
|
return single_open(file, nfsd_reply_cache_stats_show, NULL);
|
|
}
|