mirror of https://gitee.com/openkylin/linux.git
staging: Remove the Android logger driver
With the relase of Lollipop, Android no longer requires the logger driver. There are three patches which the android dev's still need before they drop logger on all their devices: [PATCH v4 1/5] pstores: use scnprintf [PATCH v2 2/5] pstore: remove superfluous memory size check [PATCH 3/5] pstore: handle zero-sized prz in series [PATCH v4 4/5] pstore: add pmsg [PATCH 5/5] pstore: selinux: add security in-core xattr support for pstore and debugfs But these seem to have been acked and are hopefully queued for upstream. So this patch removes the logger driver from staging. Cc: Rom Lemarchand <romlem@google.com>, Cc: Mark Salyzyn <salyzyn@google.com> Cc: Kees Cook <keescook@chromium.org> Cc: Android Kernel Team <kernel-team@android.com> Signed-off-by: John Stultz <john.stultz@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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parent
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commit
a0a23bbce7
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@ -14,23 +14,6 @@ config ASHMEM
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It is, in theory, a good memory allocator for low-memory devices,
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because it can discard shared memory units when under memory pressure.
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config ANDROID_LOGGER
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tristate "Android log driver"
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default n
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---help---
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This adds support for system-wide logging using four log buffers.
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These are:
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1: main
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2: events
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3: radio
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4: system
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Log reading and writing is performed via normal Linux reads and
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optimized writes. This optimization avoids logging having too
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much overhead in the system.
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config ANDROID_TIMED_OUTPUT
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bool "Timed output class driver"
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default y
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@ -1,807 +0,0 @@
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/*
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* drivers/misc/logger.c
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*
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* A Logging Subsystem
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*
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* Copyright (C) 2007-2008 Google, Inc.
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*
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* Robert Love <rlove@google.com>
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*
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* This software is licensed under the terms of the GNU General Public
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* License version 2, as published by the Free Software Foundation, and
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* may be copied, distributed, and modified under those terms.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*/
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#define pr_fmt(fmt) "logger: " fmt
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#include <linux/sched.h>
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#include <linux/module.h>
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#include <linux/fs.h>
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#include <linux/miscdevice.h>
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#include <linux/uaccess.h>
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#include <linux/poll.h>
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#include <linux/slab.h>
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#include <linux/time.h>
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#include <linux/vmalloc.h>
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#include <linux/aio.h>
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#include "logger.h"
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#include <asm/ioctls.h>
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/**
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* struct logger_log - represents a specific log, such as 'main' or 'radio'
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* @buffer: The actual ring buffer
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* @misc: The "misc" device representing the log
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* @wq: The wait queue for @readers
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* @readers: This log's readers
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* @mutex: The mutex that protects the @buffer
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* @w_off: The current write head offset
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* @head: The head, or location that readers start reading at.
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* @size: The size of the log
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* @logs: The list of log channels
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*
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* This structure lives from module insertion until module removal, so it does
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* not need additional reference counting. The structure is protected by the
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* mutex 'mutex'.
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*/
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struct logger_log {
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unsigned char *buffer;
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struct miscdevice misc;
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wait_queue_head_t wq;
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struct list_head readers;
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struct mutex mutex;
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size_t w_off;
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size_t head;
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size_t size;
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struct list_head logs;
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};
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static LIST_HEAD(log_list);
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/**
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* struct logger_reader - a logging device open for reading
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* @log: The associated log
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* @list: The associated entry in @logger_log's list
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* @r_off: The current read head offset.
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* @r_all: Reader can read all entries
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* @r_ver: Reader ABI version
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*
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* This object lives from open to release, so we don't need additional
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* reference counting. The structure is protected by log->mutex.
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*/
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struct logger_reader {
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struct logger_log *log;
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struct list_head list;
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size_t r_off;
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bool r_all;
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int r_ver;
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};
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/* logger_offset - returns index 'n' into the log via (optimized) modulus */
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static size_t logger_offset(struct logger_log *log, size_t n)
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{
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return n & (log->size - 1);
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}
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/*
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* file_get_log - Given a file structure, return the associated log
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*
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* This isn't aesthetic. We have several goals:
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*
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* 1) Need to quickly obtain the associated log during an I/O operation
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* 2) Readers need to maintain state (logger_reader)
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* 3) Writers need to be very fast (open() should be a near no-op)
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*
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* In the reader case, we can trivially go file->logger_reader->logger_log.
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* For a writer, we don't want to maintain a logger_reader, so we just go
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* file->logger_log. Thus what file->private_data points at depends on whether
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* or not the file was opened for reading. This function hides that dirtiness.
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*/
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static inline struct logger_log *file_get_log(struct file *file)
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{
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if (file->f_mode & FMODE_READ) {
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struct logger_reader *reader = file->private_data;
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return reader->log;
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}
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return file->private_data;
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}
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/*
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* get_entry_header - returns a pointer to the logger_entry header within
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* 'log' starting at offset 'off'. A temporary logger_entry 'scratch' must
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* be provided. Typically the return value will be a pointer within
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* 'logger->buf'. However, a pointer to 'scratch' may be returned if
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* the log entry spans the end and beginning of the circular buffer.
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*/
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static struct logger_entry *get_entry_header(struct logger_log *log,
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size_t off,
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struct logger_entry *scratch)
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{
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size_t len = min(sizeof(struct logger_entry), log->size - off);
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if (len != sizeof(struct logger_entry)) {
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memcpy(((void *)scratch), log->buffer + off, len);
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memcpy(((void *)scratch) + len, log->buffer,
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sizeof(struct logger_entry) - len);
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return scratch;
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}
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return (struct logger_entry *) (log->buffer + off);
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}
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/*
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* get_entry_msg_len - Grabs the length of the message of the entry
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* starting from from 'off'.
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*
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* An entry length is 2 bytes (16 bits) in host endian order.
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* In the log, the length does not include the size of the log entry structure.
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* This function returns the size including the log entry structure.
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*
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* Caller needs to hold log->mutex.
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*/
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static __u32 get_entry_msg_len(struct logger_log *log, size_t off)
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{
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struct logger_entry scratch;
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struct logger_entry *entry;
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entry = get_entry_header(log, off, &scratch);
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return entry->len;
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}
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static size_t get_user_hdr_len(int ver)
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{
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if (ver < 2)
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return sizeof(struct user_logger_entry_compat);
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return sizeof(struct logger_entry);
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}
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static ssize_t copy_header_to_user(int ver, struct logger_entry *entry,
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char __user *buf)
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{
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void *hdr;
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size_t hdr_len;
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struct user_logger_entry_compat v1;
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if (ver < 2) {
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v1.len = entry->len;
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v1.__pad = 0;
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v1.pid = entry->pid;
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v1.tid = entry->tid;
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v1.sec = entry->sec;
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v1.nsec = entry->nsec;
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hdr = &v1;
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hdr_len = sizeof(struct user_logger_entry_compat);
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} else {
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hdr = entry;
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hdr_len = sizeof(struct logger_entry);
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}
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return copy_to_user(buf, hdr, hdr_len);
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}
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/*
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* do_read_log_to_user - reads exactly 'count' bytes from 'log' into the
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* user-space buffer 'buf'. Returns 'count' on success.
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*
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* Caller must hold log->mutex.
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*/
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static ssize_t do_read_log_to_user(struct logger_log *log,
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struct logger_reader *reader,
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char __user *buf,
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size_t count)
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{
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struct logger_entry scratch;
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struct logger_entry *entry;
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size_t len;
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size_t msg_start;
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/*
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* First, copy the header to userspace, using the version of
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* the header requested
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*/
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entry = get_entry_header(log, reader->r_off, &scratch);
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if (copy_header_to_user(reader->r_ver, entry, buf))
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return -EFAULT;
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count -= get_user_hdr_len(reader->r_ver);
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buf += get_user_hdr_len(reader->r_ver);
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msg_start = logger_offset(log,
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reader->r_off + sizeof(struct logger_entry));
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/*
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* We read from the msg in two disjoint operations. First, we read from
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* the current msg head offset up to 'count' bytes or to the end of
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* the log, whichever comes first.
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*/
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len = min(count, log->size - msg_start);
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if (copy_to_user(buf, log->buffer + msg_start, len))
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return -EFAULT;
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/*
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* Second, we read any remaining bytes, starting back at the head of
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* the log.
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*/
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if (count != len)
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if (copy_to_user(buf + len, log->buffer, count - len))
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return -EFAULT;
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reader->r_off = logger_offset(log, reader->r_off +
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sizeof(struct logger_entry) + count);
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return count + get_user_hdr_len(reader->r_ver);
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}
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/*
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* get_next_entry_by_uid - Starting at 'off', returns an offset into
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* 'log->buffer' which contains the first entry readable by 'euid'
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*/
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static size_t get_next_entry_by_uid(struct logger_log *log,
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size_t off, kuid_t euid)
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{
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while (off != log->w_off) {
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struct logger_entry *entry;
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struct logger_entry scratch;
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size_t next_len;
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entry = get_entry_header(log, off, &scratch);
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if (uid_eq(entry->euid, euid))
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return off;
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next_len = sizeof(struct logger_entry) + entry->len;
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off = logger_offset(log, off + next_len);
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}
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return off;
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}
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/*
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* logger_read - our log's read() method
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*
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* Behavior:
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*
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* - O_NONBLOCK works
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* - If there are no log entries to read, blocks until log is written to
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* - Atomically reads exactly one log entry
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*
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* Will set errno to EINVAL if read
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* buffer is insufficient to hold next entry.
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*/
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static ssize_t logger_read(struct file *file, char __user *buf,
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size_t count, loff_t *pos)
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{
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struct logger_reader *reader = file->private_data;
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struct logger_log *log = reader->log;
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ssize_t ret;
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DEFINE_WAIT(wait);
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start:
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while (1) {
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mutex_lock(&log->mutex);
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prepare_to_wait(&log->wq, &wait, TASK_INTERRUPTIBLE);
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ret = (log->w_off == reader->r_off);
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mutex_unlock(&log->mutex);
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if (!ret)
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break;
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if (file->f_flags & O_NONBLOCK) {
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ret = -EAGAIN;
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break;
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}
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if (signal_pending(current)) {
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ret = -EINTR;
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break;
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}
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schedule();
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}
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finish_wait(&log->wq, &wait);
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if (ret)
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return ret;
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mutex_lock(&log->mutex);
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if (!reader->r_all)
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reader->r_off = get_next_entry_by_uid(log,
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reader->r_off, current_euid());
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/* is there still something to read or did we race? */
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if (unlikely(log->w_off == reader->r_off)) {
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mutex_unlock(&log->mutex);
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goto start;
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}
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/* get the size of the next entry */
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ret = get_user_hdr_len(reader->r_ver) +
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get_entry_msg_len(log, reader->r_off);
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if (count < ret) {
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ret = -EINVAL;
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goto out;
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}
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/* get exactly one entry from the log */
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ret = do_read_log_to_user(log, reader, buf, ret);
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out:
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mutex_unlock(&log->mutex);
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return ret;
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}
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/*
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* get_next_entry - return the offset of the first valid entry at least 'len'
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* bytes after 'off'.
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*
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* Caller must hold log->mutex.
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*/
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static size_t get_next_entry(struct logger_log *log, size_t off, size_t len)
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{
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size_t count = 0;
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do {
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size_t nr = sizeof(struct logger_entry) +
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get_entry_msg_len(log, off);
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off = logger_offset(log, off + nr);
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count += nr;
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} while (count < len);
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return off;
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}
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/*
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* is_between - is a < c < b, accounting for wrapping of a, b, and c
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* positions in the buffer
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*
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* That is, if a<b, check for c between a and b
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* and if a>b, check for c outside (not between) a and b
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*
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* |------- a xxxxxxxx b --------|
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* c^
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*
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* |xxxxx b --------- a xxxxxxxxx|
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* c^
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* or c^
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*/
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static inline int is_between(size_t a, size_t b, size_t c)
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{
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if (a < b) {
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/* is c between a and b? */
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if (a < c && c <= b)
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return 1;
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} else {
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/* is c outside of b through a? */
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if (c <= b || a < c)
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return 1;
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}
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return 0;
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}
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/*
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* fix_up_readers - walk the list of all readers and "fix up" any who were
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* lapped by the writer; also do the same for the default "start head".
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* We do this by "pulling forward" the readers and start head to the first
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* entry after the new write head.
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*
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* The caller needs to hold log->mutex.
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*/
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static void fix_up_readers(struct logger_log *log, size_t len)
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{
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size_t old = log->w_off;
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size_t new = logger_offset(log, old + len);
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struct logger_reader *reader;
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if (is_between(old, new, log->head))
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log->head = get_next_entry(log, log->head, len);
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list_for_each_entry(reader, &log->readers, list)
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if (is_between(old, new, reader->r_off))
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reader->r_off = get_next_entry(log, reader->r_off, len);
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}
|
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|
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/*
|
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* logger_write_iter - our write method, implementing support for write(),
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* writev(), and aio_write(). Writes are our fast path, and we try to optimize
|
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* them above all else.
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*/
|
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static ssize_t logger_write_iter(struct kiocb *iocb, struct iov_iter *from)
|
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{
|
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struct logger_log *log = file_get_log(iocb->ki_filp);
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struct logger_entry header;
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struct timespec now;
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size_t len, count, w_off;
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count = min_t(size_t, iocb->ki_nbytes, LOGGER_ENTRY_MAX_PAYLOAD);
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now = current_kernel_time();
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header.pid = current->tgid;
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header.tid = current->pid;
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header.sec = now.tv_sec;
|
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header.nsec = now.tv_nsec;
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header.euid = current_euid();
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header.len = count;
|
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header.hdr_size = sizeof(struct logger_entry);
|
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|
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/* null writes succeed, return zero */
|
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if (unlikely(!header.len))
|
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return 0;
|
||||
|
||||
mutex_lock(&log->mutex);
|
||||
|
||||
/*
|
||||
* Fix up any readers, pulling them forward to the first readable
|
||||
* entry after (what will be) the new write offset. We do this now
|
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* because if we partially fail, we can end up with clobbered log
|
||||
* entries that encroach on readable buffer.
|
||||
*/
|
||||
fix_up_readers(log, sizeof(struct logger_entry) + header.len);
|
||||
|
||||
len = min(sizeof(header), log->size - log->w_off);
|
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memcpy(log->buffer + log->w_off, &header, len);
|
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memcpy(log->buffer, (char *)&header + len, sizeof(header) - len);
|
||||
|
||||
/* Work with a copy until we are ready to commit the whole entry */
|
||||
w_off = logger_offset(log, log->w_off + sizeof(struct logger_entry));
|
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|
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len = min(count, log->size - w_off);
|
||||
|
||||
if (copy_from_iter(log->buffer + w_off, len, from) != len) {
|
||||
/*
|
||||
* Note that by not updating log->w_off, this abandons the
|
||||
* portion of the new entry that *was* successfully
|
||||
* copied, just above. This is intentional to avoid
|
||||
* message corruption from missing fragments.
|
||||
*/
|
||||
mutex_unlock(&log->mutex);
|
||||
return -EFAULT;
|
||||
}
|
||||
|
||||
if (copy_from_iter(log->buffer, count - len, from) != count - len) {
|
||||
mutex_unlock(&log->mutex);
|
||||
return -EFAULT;
|
||||
}
|
||||
|
||||
log->w_off = logger_offset(log, w_off + count);
|
||||
mutex_unlock(&log->mutex);
|
||||
|
||||
/* wake up any blocked readers */
|
||||
wake_up_interruptible(&log->wq);
|
||||
|
||||
return len;
|
||||
}
|
||||
|
||||
static struct logger_log *get_log_from_minor(int minor)
|
||||
{
|
||||
struct logger_log *log;
|
||||
|
||||
list_for_each_entry(log, &log_list, logs)
|
||||
if (log->misc.minor == minor)
|
||||
return log;
|
||||
return NULL;
|
||||
}
|
||||
|
||||
/*
|
||||
* logger_open - the log's open() file operation
|
||||
*
|
||||
* Note how near a no-op this is in the write-only case. Keep it that way!
|
||||
*/
|
||||
static int logger_open(struct inode *inode, struct file *file)
|
||||
{
|
||||
struct logger_log *log;
|
||||
int ret;
|
||||
|
||||
ret = nonseekable_open(inode, file);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
log = get_log_from_minor(MINOR(inode->i_rdev));
|
||||
if (!log)
|
||||
return -ENODEV;
|
||||
|
||||
if (file->f_mode & FMODE_READ) {
|
||||
struct logger_reader *reader;
|
||||
|
||||
reader = kmalloc(sizeof(struct logger_reader), GFP_KERNEL);
|
||||
if (!reader)
|
||||
return -ENOMEM;
|
||||
|
||||
reader->log = log;
|
||||
reader->r_ver = 1;
|
||||
reader->r_all = in_egroup_p(inode->i_gid) ||
|
||||
capable(CAP_SYSLOG);
|
||||
|
||||
INIT_LIST_HEAD(&reader->list);
|
||||
|
||||
mutex_lock(&log->mutex);
|
||||
reader->r_off = log->head;
|
||||
list_add_tail(&reader->list, &log->readers);
|
||||
mutex_unlock(&log->mutex);
|
||||
|
||||
file->private_data = reader;
|
||||
} else {
|
||||
file->private_data = log;
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* logger_release - the log's release file operation
|
||||
*
|
||||
* Note this is a total no-op in the write-only case. Keep it that way!
|
||||
*/
|
||||
static int logger_release(struct inode *ignored, struct file *file)
|
||||
{
|
||||
if (file->f_mode & FMODE_READ) {
|
||||
struct logger_reader *reader = file->private_data;
|
||||
struct logger_log *log = reader->log;
|
||||
|
||||
mutex_lock(&log->mutex);
|
||||
list_del(&reader->list);
|
||||
mutex_unlock(&log->mutex);
|
||||
|
||||
kfree(reader);
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* logger_poll - the log's poll file operation, for poll/select/epoll
|
||||
*
|
||||
* Note we always return POLLOUT, because you can always write() to the log.
|
||||
* Note also that, strictly speaking, a return value of POLLIN does not
|
||||
* guarantee that the log is readable without blocking, as there is a small
|
||||
* chance that the writer can lap the reader in the interim between poll()
|
||||
* returning and the read() request.
|
||||
*/
|
||||
static unsigned int logger_poll(struct file *file, poll_table *wait)
|
||||
{
|
||||
struct logger_reader *reader;
|
||||
struct logger_log *log;
|
||||
unsigned int ret = POLLOUT | POLLWRNORM;
|
||||
|
||||
if (!(file->f_mode & FMODE_READ))
|
||||
return ret;
|
||||
|
||||
reader = file->private_data;
|
||||
log = reader->log;
|
||||
|
||||
poll_wait(file, &log->wq, wait);
|
||||
|
||||
mutex_lock(&log->mutex);
|
||||
if (!reader->r_all)
|
||||
reader->r_off = get_next_entry_by_uid(log,
|
||||
reader->r_off, current_euid());
|
||||
|
||||
if (log->w_off != reader->r_off)
|
||||
ret |= POLLIN | POLLRDNORM;
|
||||
mutex_unlock(&log->mutex);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
static long logger_set_version(struct logger_reader *reader, void __user *arg)
|
||||
{
|
||||
int version;
|
||||
|
||||
if (copy_from_user(&version, arg, sizeof(int)))
|
||||
return -EFAULT;
|
||||
|
||||
if ((version < 1) || (version > 2))
|
||||
return -EINVAL;
|
||||
|
||||
reader->r_ver = version;
|
||||
return 0;
|
||||
}
|
||||
|
||||
static long logger_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
|
||||
{
|
||||
struct logger_log *log = file_get_log(file);
|
||||
struct logger_reader *reader;
|
||||
long ret = -EINVAL;
|
||||
void __user *argp = (void __user *)arg;
|
||||
|
||||
mutex_lock(&log->mutex);
|
||||
|
||||
switch (cmd) {
|
||||
case LOGGER_GET_LOG_BUF_SIZE:
|
||||
ret = log->size;
|
||||
break;
|
||||
case LOGGER_GET_LOG_LEN:
|
||||
if (!(file->f_mode & FMODE_READ)) {
|
||||
ret = -EBADF;
|
||||
break;
|
||||
}
|
||||
reader = file->private_data;
|
||||
if (log->w_off >= reader->r_off)
|
||||
ret = log->w_off - reader->r_off;
|
||||
else
|
||||
ret = (log->size - reader->r_off) + log->w_off;
|
||||
break;
|
||||
case LOGGER_GET_NEXT_ENTRY_LEN:
|
||||
if (!(file->f_mode & FMODE_READ)) {
|
||||
ret = -EBADF;
|
||||
break;
|
||||
}
|
||||
reader = file->private_data;
|
||||
|
||||
if (!reader->r_all)
|
||||
reader->r_off = get_next_entry_by_uid(log,
|
||||
reader->r_off, current_euid());
|
||||
|
||||
if (log->w_off != reader->r_off)
|
||||
ret = get_user_hdr_len(reader->r_ver) +
|
||||
get_entry_msg_len(log, reader->r_off);
|
||||
else
|
||||
ret = 0;
|
||||
break;
|
||||
case LOGGER_FLUSH_LOG:
|
||||
if (!(file->f_mode & FMODE_WRITE)) {
|
||||
ret = -EBADF;
|
||||
break;
|
||||
}
|
||||
if (!(in_egroup_p(file_inode(file)->i_gid) ||
|
||||
capable(CAP_SYSLOG))) {
|
||||
ret = -EPERM;
|
||||
break;
|
||||
}
|
||||
list_for_each_entry(reader, &log->readers, list)
|
||||
reader->r_off = log->w_off;
|
||||
log->head = log->w_off;
|
||||
ret = 0;
|
||||
break;
|
||||
case LOGGER_GET_VERSION:
|
||||
if (!(file->f_mode & FMODE_READ)) {
|
||||
ret = -EBADF;
|
||||
break;
|
||||
}
|
||||
reader = file->private_data;
|
||||
ret = reader->r_ver;
|
||||
break;
|
||||
case LOGGER_SET_VERSION:
|
||||
if (!(file->f_mode & FMODE_READ)) {
|
||||
ret = -EBADF;
|
||||
break;
|
||||
}
|
||||
reader = file->private_data;
|
||||
ret = logger_set_version(reader, argp);
|
||||
break;
|
||||
}
|
||||
|
||||
mutex_unlock(&log->mutex);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
static const struct file_operations logger_fops = {
|
||||
.owner = THIS_MODULE,
|
||||
.read = logger_read,
|
||||
.write_iter = logger_write_iter,
|
||||
.poll = logger_poll,
|
||||
.unlocked_ioctl = logger_ioctl,
|
||||
.compat_ioctl = logger_ioctl,
|
||||
.open = logger_open,
|
||||
.release = logger_release,
|
||||
};
|
||||
|
||||
/*
|
||||
* Log size must must be a power of two, and greater than
|
||||
* (LOGGER_ENTRY_MAX_PAYLOAD + sizeof(struct logger_entry)).
|
||||
*/
|
||||
static int __init create_log(char *log_name, int size)
|
||||
{
|
||||
int ret = 0;
|
||||
struct logger_log *log;
|
||||
unsigned char *buffer;
|
||||
|
||||
buffer = vmalloc(size);
|
||||
if (buffer == NULL)
|
||||
return -ENOMEM;
|
||||
|
||||
log = kzalloc(sizeof(struct logger_log), GFP_KERNEL);
|
||||
if (log == NULL) {
|
||||
ret = -ENOMEM;
|
||||
goto out_free_buffer;
|
||||
}
|
||||
log->buffer = buffer;
|
||||
|
||||
log->misc.minor = MISC_DYNAMIC_MINOR;
|
||||
log->misc.name = kstrdup(log_name, GFP_KERNEL);
|
||||
if (log->misc.name == NULL) {
|
||||
ret = -ENOMEM;
|
||||
goto out_free_log;
|
||||
}
|
||||
|
||||
log->misc.fops = &logger_fops;
|
||||
log->misc.parent = NULL;
|
||||
|
||||
init_waitqueue_head(&log->wq);
|
||||
INIT_LIST_HEAD(&log->readers);
|
||||
mutex_init(&log->mutex);
|
||||
log->w_off = 0;
|
||||
log->head = 0;
|
||||
log->size = size;
|
||||
|
||||
INIT_LIST_HEAD(&log->logs);
|
||||
list_add_tail(&log->logs, &log_list);
|
||||
|
||||
/* finally, initialize the misc device for this log */
|
||||
ret = misc_register(&log->misc);
|
||||
if (unlikely(ret)) {
|
||||
pr_err("failed to register misc device for log '%s'!\n",
|
||||
log->misc.name);
|
||||
goto out_free_misc_name;
|
||||
}
|
||||
|
||||
pr_info("created %luK log '%s'\n",
|
||||
(unsigned long)log->size >> 10, log->misc.name);
|
||||
|
||||
return 0;
|
||||
|
||||
out_free_misc_name:
|
||||
kfree(log->misc.name);
|
||||
|
||||
out_free_log:
|
||||
kfree(log);
|
||||
|
||||
out_free_buffer:
|
||||
vfree(buffer);
|
||||
return ret;
|
||||
}
|
||||
|
||||
static int __init logger_init(void)
|
||||
{
|
||||
int ret;
|
||||
|
||||
ret = create_log(LOGGER_LOG_MAIN, 256*1024);
|
||||
if (unlikely(ret))
|
||||
goto out;
|
||||
|
||||
ret = create_log(LOGGER_LOG_EVENTS, 256*1024);
|
||||
if (unlikely(ret))
|
||||
goto out;
|
||||
|
||||
ret = create_log(LOGGER_LOG_RADIO, 256*1024);
|
||||
if (unlikely(ret))
|
||||
goto out;
|
||||
|
||||
ret = create_log(LOGGER_LOG_SYSTEM, 256*1024);
|
||||
if (unlikely(ret))
|
||||
goto out;
|
||||
|
||||
out:
|
||||
return ret;
|
||||
}
|
||||
|
||||
static void __exit logger_exit(void)
|
||||
{
|
||||
struct logger_log *current_log, *next_log;
|
||||
|
||||
list_for_each_entry_safe(current_log, next_log, &log_list, logs) {
|
||||
/* we have to delete all the entry inside log_list */
|
||||
misc_deregister(¤t_log->misc);
|
||||
vfree(current_log->buffer);
|
||||
kfree(current_log->misc.name);
|
||||
list_del(¤t_log->logs);
|
||||
kfree(current_log);
|
||||
}
|
||||
}
|
||||
|
||||
device_initcall(logger_init);
|
||||
module_exit(logger_exit);
|
||||
|
||||
MODULE_LICENSE("GPL");
|
||||
MODULE_AUTHOR("Robert Love, <rlove@google.com>");
|
||||
MODULE_DESCRIPTION("Android Logger");
|
|
@ -1,89 +0,0 @@
|
|||
/* include/linux/logger.h
|
||||
*
|
||||
* Copyright (C) 2007-2008 Google, Inc.
|
||||
* Author: Robert Love <rlove@android.com>
|
||||
*
|
||||
* This software is licensed under the terms of the GNU General Public
|
||||
* License version 2, as published by the Free Software Foundation, and
|
||||
* may be copied, distributed, and modified under those terms.
|
||||
*
|
||||
* 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 for more details.
|
||||
*
|
||||
*/
|
||||
|
||||
#ifndef _LINUX_LOGGER_H
|
||||
#define _LINUX_LOGGER_H
|
||||
|
||||
#include <linux/types.h>
|
||||
#include <linux/ioctl.h>
|
||||
|
||||
/**
|
||||
* struct user_logger_entry_compat - defines a single entry that is given to a logger
|
||||
* @len: The length of the payload
|
||||
* @__pad: Two bytes of padding that appear to be required
|
||||
* @pid: The generating process' process ID
|
||||
* @tid: The generating process' thread ID
|
||||
* @sec: The number of seconds that have elapsed since the Epoch
|
||||
* @nsec: The number of nanoseconds that have elapsed since @sec
|
||||
* @msg: The message that is to be logged
|
||||
*
|
||||
* The userspace structure for version 1 of the logger_entry ABI.
|
||||
* This structure is returned to userspace unless the caller requests
|
||||
* an upgrade to a newer ABI version.
|
||||
*/
|
||||
struct user_logger_entry_compat {
|
||||
__u16 len;
|
||||
__u16 __pad;
|
||||
__s32 pid;
|
||||
__s32 tid;
|
||||
__s32 sec;
|
||||
__s32 nsec;
|
||||
char msg[0];
|
||||
};
|
||||
|
||||
/**
|
||||
* struct logger_entry - defines a single entry that is given to a logger
|
||||
* @len: The length of the payload
|
||||
* @hdr_size: sizeof(struct logger_entry_v2)
|
||||
* @pid: The generating process' process ID
|
||||
* @tid: The generating process' thread ID
|
||||
* @sec: The number of seconds that have elapsed since the Epoch
|
||||
* @nsec: The number of nanoseconds that have elapsed since @sec
|
||||
* @euid: Effective UID of logger
|
||||
* @msg: The message that is to be logged
|
||||
*
|
||||
* The structure for version 2 of the logger_entry ABI.
|
||||
* This structure is returned to userspace if ioctl(LOGGER_SET_VERSION)
|
||||
* is called with version >= 2
|
||||
*/
|
||||
struct logger_entry {
|
||||
__u16 len;
|
||||
__u16 hdr_size;
|
||||
__s32 pid;
|
||||
__s32 tid;
|
||||
__s32 sec;
|
||||
__s32 nsec;
|
||||
kuid_t euid;
|
||||
char msg[0];
|
||||
};
|
||||
|
||||
#define LOGGER_LOG_RADIO "log_radio" /* radio-related messages */
|
||||
#define LOGGER_LOG_EVENTS "log_events" /* system/hardware events */
|
||||
#define LOGGER_LOG_SYSTEM "log_system" /* system/framework messages */
|
||||
#define LOGGER_LOG_MAIN "log_main" /* everything else */
|
||||
|
||||
#define LOGGER_ENTRY_MAX_PAYLOAD 4076
|
||||
|
||||
#define __LOGGERIO 0xAE
|
||||
|
||||
#define LOGGER_GET_LOG_BUF_SIZE _IO(__LOGGERIO, 1) /* size of log */
|
||||
#define LOGGER_GET_LOG_LEN _IO(__LOGGERIO, 2) /* used log len */
|
||||
#define LOGGER_GET_NEXT_ENTRY_LEN _IO(__LOGGERIO, 3) /* next entry len */
|
||||
#define LOGGER_FLUSH_LOG _IO(__LOGGERIO, 4) /* flush log */
|
||||
#define LOGGER_GET_VERSION _IO(__LOGGERIO, 5) /* abi version */
|
||||
#define LOGGER_SET_VERSION _IO(__LOGGERIO, 6) /* abi version */
|
||||
|
||||
#endif /* _LINUX_LOGGER_H */
|
Loading…
Reference in New Issue