+++ /dev/null
-/*
- * GPL HEADER START
- *
- * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 only,
- * as published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * General Public License version 2 for more details (a copy is included
- * in the LICENSE file that accompanied this code).
- *
- * You should have received a copy of the GNU General Public License
- * version 2 along with this program; If not, see
- * http://www.gnu.org/licenses/gpl-2.0.html
- *
- * GPL HEADER END
- */
-/*
- * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
- * Use is subject to license terms.
- *
- * Copyright (c) 2012, 2017, Intel Corporation.
- */
-/*
- * This file is part of Lustre, http://www.lustre.org/
- * Lustre is a trademark of Sun Microsystems, Inc.
- *
- * libcfs/libcfs/linux/linux-curproc.c
- *
- * Lustre curproc API implementation for Linux kernel
- *
- * Author: Nikita Danilov <nikita@clusterfs.com>
- */
-
-#include <linux/sched.h>
-#ifdef HAVE_SCHED_HEADERS
-#include <linux/sched/signal.h>
-#include <linux/sched/mm.h>
-#endif
-#include <linux/fs_struct.h>
-#include <linux/pagemap.h>
-#include <linux/compat.h>
-#include <linux/thread_info.h>
-
-#define DEBUG_SUBSYSTEM S_LNET
-
-#include <libcfs/libcfs.h>
-
-/*
- * Implementation of cfs_curproc API (see portals/include/libcfs/curproc.h)
- * for Linux kernel.
- */
-
-/* Currently all the CFS_CAP_* defines match CAP_* ones. */
-#define cfs_cap_pack(cap) (cap)
-#define cfs_cap_unpack(cap) (cap)
-
-void cfs_cap_raise(cfs_cap_t cap)
-{
- struct cred *cred;
- if ((cred = prepare_creds())) {
- cap_raise(cred->cap_effective, cfs_cap_unpack(cap));
- commit_creds(cred);
- }
-}
-
-void cfs_cap_lower(cfs_cap_t cap)
-{
- struct cred *cred;
- if ((cred = prepare_creds())) {
- cap_lower(cred->cap_effective, cfs_cap_unpack(cap));
- commit_creds(cred);
- }
-}
-
-int cfs_cap_raised(cfs_cap_t cap)
-{
- return cap_raised(current_cap(), cfs_cap_unpack(cap));
-}
-
-static void cfs_kernel_cap_pack(kernel_cap_t kcap, cfs_cap_t *cap)
-{
-#if defined (_LINUX_CAPABILITY_VERSION) && _LINUX_CAPABILITY_VERSION == 0x19980330
- *cap = cfs_cap_pack(kcap);
-#elif defined (_LINUX_CAPABILITY_VERSION) && _LINUX_CAPABILITY_VERSION == 0x20071026
- *cap = cfs_cap_pack(kcap[0]);
-#elif defined(_KERNEL_CAPABILITY_VERSION) && _KERNEL_CAPABILITY_VERSION == 0x20080522
- /* XXX lost high byte */
- *cap = cfs_cap_pack(kcap.cap[0]);
-#else
- #error "need correct _KERNEL_CAPABILITY_VERSION "
-#endif
-}
-
-static void cfs_kernel_cap_unpack(kernel_cap_t *kcap, cfs_cap_t cap)
-{
-#if defined (_LINUX_CAPABILITY_VERSION) && _LINUX_CAPABILITY_VERSION == 0x19980330
- *kcap = cfs_cap_unpack(cap);
-#elif defined (_LINUX_CAPABILITY_VERSION) && _LINUX_CAPABILITY_VERSION == 0x20071026
- (*kcap)[0] = cfs_cap_unpack(cap);
-#elif defined(_KERNEL_CAPABILITY_VERSION) && _KERNEL_CAPABILITY_VERSION == 0x20080522
- kcap->cap[0] = cfs_cap_unpack(cap);
-#else
- #error "need correct _KERNEL_CAPABILITY_VERSION "
-#endif
-}
-
-cfs_cap_t cfs_curproc_cap_pack(void)
-{
- cfs_cap_t cap;
- cfs_kernel_cap_pack(current_cap(), &cap);
- return cap;
-}
-
-void cfs_curproc_cap_unpack(cfs_cap_t cap)
-{
- struct cred *cred;
- if ((cred = prepare_creds())) {
- cfs_kernel_cap_unpack(&cred->cap_effective, cap);
- commit_creds(cred);
- }
-}
-
-int cfs_capable(cfs_cap_t cap)
-{
- return capable(cfs_cap_unpack(cap));
-}
-
-static int cfs_access_process_vm(struct task_struct *tsk,
- struct mm_struct *mm,
- unsigned long addr,
- void *buf, int len, int write)
-{
- /* Just copied from kernel for the kernels which doesn't
- * have access_process_vm() exported */
- struct vm_area_struct *vma;
- struct page *page;
- void *old_buf = buf;
-
- /* Avoid deadlocks on mmap_sem if called from sys_mmap_pgoff(),
- * which is already holding mmap_sem for writes. If some other
- * thread gets the write lock in the meantime, this thread will
- * block, but at least it won't deadlock on itself. LU-1735 */
- if (down_read_trylock(&mm->mmap_sem) == 0)
- return -EDEADLK;
-
- /* ignore errors, just check how much was successfully transferred */
- while (len) {
- int bytes, rc, offset;
- void *maddr;
-
-#if defined(HAVE_GET_USER_PAGES_GUP_FLAGS)
- rc = get_user_pages(addr, 1, write ? FOLL_WRITE : 0, &page, &vma);
-#elif defined(HAVE_GET_USER_PAGES_6ARG)
- rc = get_user_pages(addr, 1, write, 1, &page, &vma);
-#else
- rc = get_user_pages(tsk, mm, addr, 1, write, 1, &page, &vma);
-#endif
- if (rc <= 0)
- break;
-
- bytes = len;
- offset = addr & (PAGE_SIZE-1);
- if (bytes > PAGE_SIZE-offset)
- bytes = PAGE_SIZE-offset;
-
- maddr = kmap(page);
- if (write) {
- copy_to_user_page(vma, page, addr,
- maddr + offset, buf, bytes);
- set_page_dirty_lock(page);
- } else {
- copy_from_user_page(vma, page, addr,
- buf, maddr + offset, bytes);
- }
- kunmap(page);
- put_page(page);
- len -= bytes;
- buf += bytes;
- addr += bytes;
- }
- up_read(&mm->mmap_sem);
-
- return buf - old_buf;
-}
-
-/* Read the environment variable of current process specified by @key. */
-int cfs_get_environ(const char *key, char *value, int *val_len)
-{
- struct mm_struct *mm;
- char *buffer;
- int buf_len = PAGE_SIZE;
- int key_len = strlen(key);
- unsigned long addr;
- int rc;
- bool skip = false;
- ENTRY;
-
- buffer = kmalloc(buf_len, GFP_USER);
- if (!buffer)
- RETURN(-ENOMEM);
-
- mm = get_task_mm(current);
- if (!mm) {
- kfree(buffer);
- RETURN(-EINVAL);
- }
-
- addr = mm->env_start;
- while (addr < mm->env_end) {
- int this_len, retval, scan_len;
- char *env_start, *env_end;
-
- memset(buffer, 0, buf_len);
-
- this_len = min_t(int, mm->env_end - addr, buf_len);
- retval = cfs_access_process_vm(current, mm, addr, buffer,
- this_len, 0);
- if (retval < 0)
- GOTO(out, rc = retval);
- else if (retval != this_len)
- break;
-
- addr += retval;
-
- /* Parse the buffer to find out the specified key/value pair.
- * The "key=value" entries are separated by '\0'. */
- env_start = buffer;
- scan_len = this_len;
- while (scan_len) {
- char *entry;
- int entry_len;
-
- env_end = memscan(env_start, '\0', scan_len);
- LASSERT(env_end >= env_start &&
- env_end <= env_start + scan_len);
-
- /* The last entry of this buffer cross the buffer
- * boundary, reread it in next cycle. */
- if (unlikely(env_end - env_start == scan_len)) {
- /* Just skip the entry larger than page size,
- * it can't be jobID env variable. */
- if (unlikely(scan_len == this_len))
- skip = true;
- else
- addr -= scan_len;
- break;
- } else if (unlikely(skip)) {
- skip = false;
- goto skip;
- }
-
- entry = env_start;
- entry_len = env_end - env_start;
-
- /* Key length + length of '=' */
- if (entry_len > key_len + 1 &&
- !memcmp(entry, key, key_len)) {
- entry += key_len + 1;
- entry_len -= key_len + 1;
- /* The 'value' buffer passed in is too small.*/
- if (entry_len >= *val_len)
- GOTO(out, rc = -EOVERFLOW);
-
- memcpy(value, entry, entry_len);
- *val_len = entry_len;
- GOTO(out, rc = 0);
- }
-skip:
- scan_len -= (env_end - env_start + 1);
- env_start = env_end + 1;
- }
- }
- GOTO(out, rc = -ENOENT);
-
-out:
- mmput(mm);
- kfree((void *)buffer);
- return rc;
-}
-EXPORT_SYMBOL(cfs_get_environ);
-
-EXPORT_SYMBOL(cfs_cap_raise);
-EXPORT_SYMBOL(cfs_cap_lower);
-EXPORT_SYMBOL(cfs_cap_raised);
-EXPORT_SYMBOL(cfs_curproc_cap_pack);
-EXPORT_SYMBOL(cfs_capable);
-
-/*
- * Local variables:
- * c-indentation-style: "K&R"
- * c-basic-offset: 8
- * tab-width: 8
- * fill-column: 80
- * scroll-step: 1
- * End:
- */
git://git.whamcloud.com / fs / lustre-release.git / blobdiff