/* * Sample kfifo byte stream implementation * * Copyright (C) 2010 Stefani Seibold * * Released under the GPL version 2 only. * */ #include #include #include #include #include /* * This module shows how to create a byte stream fifo. */ /* fifo size in elements (bytes) */ #define FIFO_SIZE 32 /* name of the proc entry */ #define PROC_FIFO "bytestream-fifo" /* lock for procfs read access */ static DEFINE_MUTEX(read_lock); /* lock for procfs write access */ static DEFINE_MUTEX(write_lock); /* * define DYNAMIC in this example for a dynamically allocated fifo. * * Otherwise the fifo storage will be a part of the fifo structure. */ #if 0 #define DYNAMIC #endif #ifdef DYNAMIC static struct kfifo test; #else static DECLARE_KFIFO(test, unsigned char, FIFO_SIZE); #endif static const unsigned char expected_result[FIFO_SIZE] = { 3, 4, 5, 6, 7, 8, 9, 0, 1, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, }; static int __init testfunc(void) { unsigned char buf[6]; unsigned char i, j; unsigned int ret; printk(KERN_INFO "byte stream fifo test start\n"); /* put string into the fifo */ kfifo_in(&test, "hello", 5); /* put values into the fifo */ for (i = 0; i != 10; i++) kfifo_put(&test, i); /* show the number of used elements */ printk(KERN_INFO "fifo len: %u\n", kfifo_len(&test)); /* get max of 5 bytes from the fifo */ i = kfifo_out(&test, buf, 5); printk(KERN_INFO "buf: %.*s\n", i, buf); /* get max of 2 elements from the fifo */ ret = kfifo_out(&test, buf, 2); printk(KERN_INFO "ret: %d\n", ret); /* and put it back to the end of the fifo */ ret = kfifo_in(&test, buf, ret); printk(KERN_INFO "ret: %d\n", ret); /* skip first element of the fifo */ printk(KERN_INFO "skip 1st element\n"); kfifo_skip(&test); /* put values into the fifo until is full */ for (i = 20; kfifo_put(&test, i); i++) ; printk(KERN_INFO "queue len: %u\n", kfifo_len(&test)); /* show the first value without removing from the fifo */ if (kfifo_peek(&test, &i)) printk(KERN_INFO "%d\n", i); /* check the correctness of all values in the fifo */ j = 0; while (kfifo_get(&test, &i)) { printk(KERN_INFO "item = %d\n", i); if (i != expected_result[j++]) { printk(KERN_WARNING "value mismatch: test failed\n"); return -EIO; } } if (j != ARRAY_SIZE(expected_result)) { printk(KERN_WARNING "size mismatch: test failed\n"); return -EIO; } printk(KERN_INFO "test passed\n"); return 0; } static ssize_t fifo_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos) { int ret; unsigned int copied; if (mutex_lock_interruptible(&write_lock)) return -ERESTARTSYS; ret = kfifo_from_user(&test, buf, count, &copied); mutex_unlock(&write_lock); return ret ? ret : copied; } static ssize_t fifo_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) { int ret; unsigned int copied; if (mutex_lock_interruptible(&read_lock)) return -ERESTARTSYS; ret = kfifo_to_user(&test, buf, count, &copied); mutex_unlock(&read_lock); return ret ? ret : copied; } static const struct file_operations fifo_fops = { .owner = THIS_MODULE, .read = fifo_read, .write = fifo_write, .llseek = noop_llseek, }; static int __init example_init(void) { #ifdef DYNAMIC int ret; ret = kfifo_alloc(&test, FIFO_SIZE, GFP_KERNEL); if (ret) { printk(KERN_ERR "error kfifo_alloc\n"); return ret; } #else INIT_KFIFO(test); #endif if (testfunc() < 0) { #ifdef DYNAMIC kfifo_free(&test); #endif return -EIO; } if (proc_create(PROC_FIFO, 0, NULL, &fifo_fops) == NULL) { #ifdef DYNAMIC kfifo_free(&test); #endif return -ENOMEM; } return 0; } static void __exit example_exit(void) { remove_proc_entry(PROC_FIFO, NULL); #ifdef DYNAMIC kfifo_free(&test); #endif } module_init(example_init); module_exit(example_exit); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Stefani Seibold "); d class='label'>mode:
authorVincent <vincent.stehle@laposte.net>2017-01-30 15:06:43 +0100
committerDavid S. Miller <davem@davemloft.net>2017-01-31 13:07:40 -0500
commitc73e44269369e936165f0f9b61f1f09a11dae01c (patch)
treee2188e900ba06302f8ed2746cb07edd3efbc5c35 /net/kcm/kcmsock.c
parent040587af31228d82c52267f717c9fcdb65f36335 (diff)
net: thunderx: avoid dereferencing xcv when NULL
This fixes the following smatch and coccinelle warnings: drivers/net/ethernet/cavium/thunder/thunder_xcv.c:119 xcv_setup_link() error: we previously assumed 'xcv' could be null (see line 118) [smatch] drivers/net/ethernet/cavium/thunder/thunder_xcv.c:119:16-20: ERROR: xcv is NULL but dereferenced. [coccinelle] Fixes: 6465859aba1e66a5 ("net: thunderx: Add RGMII interface type support") Signed-off-by: Vincent Stehlé <vincent.stehle@laposte.net> Cc: Sunil Goutham <sgoutham@cavium.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/kcm/kcmsock.c')