cb787f4ac0
no_llseek had been defined to NULL two years ago, in commit 868941b144
("fs: remove no_llseek")
To quote that commit,
At -rc1 we'll need do a mechanical removal of no_llseek -
git grep -l -w no_llseek | grep -v porting.rst | while read i; do
sed -i '/\<no_llseek\>/d' $i
done
would do it.
Unfortunately, that hadn't been done. Linus, could you do that now, so
that we could finally put that thing to rest? All instances are of the
form
.llseek = no_llseek,
so it's obviously safe.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
70 lines
1.6 KiB
C
70 lines
1.6 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* The USB Monitor, inspired by Dave Harding's USBMon.
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*
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* This is the 's' or 'stat' reader which debugs usbmon itself.
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* Note that this code blows through locks, so make sure that
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* /dbg/usbmon/0s is well protected from non-root users.
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*
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*/
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#include <linux/kernel.h>
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#include <linux/slab.h>
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#include <linux/export.h>
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#include <linux/usb.h>
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#include <linux/fs.h>
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#include <linux/uaccess.h>
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#include "usb_mon.h"
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#define STAT_BUF_SIZE 80
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struct snap {
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int slen;
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char str[STAT_BUF_SIZE];
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};
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static int mon_stat_open(struct inode *inode, struct file *file)
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{
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struct mon_bus *mbus;
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struct snap *sp;
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sp = kmalloc(sizeof(struct snap), GFP_KERNEL);
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if (sp == NULL)
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return -ENOMEM;
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mbus = inode->i_private;
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sp->slen = scnprintf(sp->str, STAT_BUF_SIZE,
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"nreaders %d events %u text_lost %u\n",
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mbus->nreaders, mbus->cnt_events, mbus->cnt_text_lost);
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file->private_data = sp;
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return 0;
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}
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static ssize_t mon_stat_read(struct file *file, char __user *buf,
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size_t nbytes, loff_t *ppos)
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{
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struct snap *sp = file->private_data;
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return simple_read_from_buffer(buf, nbytes, ppos, sp->str, sp->slen);
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}
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static int mon_stat_release(struct inode *inode, struct file *file)
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{
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struct snap *sp = file->private_data;
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file->private_data = NULL;
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kfree(sp);
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return 0;
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}
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const struct file_operations mon_fops_stat = {
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.owner = THIS_MODULE,
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.open = mon_stat_open,
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.read = mon_stat_read,
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/* .write = mon_stat_write, */
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/* .poll = mon_stat_poll, */
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/* .unlocked_ioctl = mon_stat_ioctl, */
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.release = mon_stat_release,
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};
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