Revision e09e200e07222467ef82367bff7cc6f44ad00397 authored by Andy Shevchenko on 30 September 2020, 14:20:12 UTC, committed by Linus Walleij on 01 October 2020, 08:00:17 UTC
In IRQ handler we have to clear bitmap before use. Currently the GCC extension has been used for that. For sake of the consistency switch to bitmap API. As expected bloat-o-meter shows no difference in the object size. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Bartosz Golaszewski <bgolaszewski@baylibre.com> Link: https://lore.kernel.org/r/20200930142013.59247-1-andriy.shevchenko@linux.intel.com Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
1 parent 17479aa
anon_inodes.c
// SPDX-License-Identifier: GPL-2.0-only
/*
* fs/anon_inodes.c
*
* Copyright (C) 2007 Davide Libenzi <davidel@xmailserver.org>
*
* Thanks to Arnd Bergmann for code review and suggestions.
* More changes for Thomas Gleixner suggestions.
*
*/
#include <linux/cred.h>
#include <linux/file.h>
#include <linux/poll.h>
#include <linux/sched.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/mount.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/magic.h>
#include <linux/anon_inodes.h>
#include <linux/pseudo_fs.h>
#include <linux/uaccess.h>
static struct vfsmount *anon_inode_mnt __read_mostly;
static struct inode *anon_inode_inode;
/*
* anon_inodefs_dname() is called from d_path().
*/
static char *anon_inodefs_dname(struct dentry *dentry, char *buffer, int buflen)
{
return dynamic_dname(dentry, buffer, buflen, "anon_inode:%s",
dentry->d_name.name);
}
static const struct dentry_operations anon_inodefs_dentry_operations = {
.d_dname = anon_inodefs_dname,
};
static int anon_inodefs_init_fs_context(struct fs_context *fc)
{
struct pseudo_fs_context *ctx = init_pseudo(fc, ANON_INODE_FS_MAGIC);
if (!ctx)
return -ENOMEM;
ctx->dops = &anon_inodefs_dentry_operations;
return 0;
}
static struct file_system_type anon_inode_fs_type = {
.name = "anon_inodefs",
.init_fs_context = anon_inodefs_init_fs_context,
.kill_sb = kill_anon_super,
};
/**
* anon_inode_getfile - creates a new file instance by hooking it up to an
* anonymous inode, and a dentry that describe the "class"
* of the file
*
* @name: [in] name of the "class" of the new file
* @fops: [in] file operations for the new file
* @priv: [in] private data for the new file (will be file's private_data)
* @flags: [in] flags
*
* Creates a new file by hooking it on a single inode. This is useful for files
* that do not need to have a full-fledged inode in order to operate correctly.
* All the files created with anon_inode_getfile() will share a single inode,
* hence saving memory and avoiding code duplication for the file/inode/dentry
* setup. Returns the newly created file* or an error pointer.
*/
struct file *anon_inode_getfile(const char *name,
const struct file_operations *fops,
void *priv, int flags)
{
struct file *file;
if (IS_ERR(anon_inode_inode))
return ERR_PTR(-ENODEV);
if (fops->owner && !try_module_get(fops->owner))
return ERR_PTR(-ENOENT);
/*
* We know the anon_inode inode count is always greater than zero,
* so ihold() is safe.
*/
ihold(anon_inode_inode);
file = alloc_file_pseudo(anon_inode_inode, anon_inode_mnt, name,
flags & (O_ACCMODE | O_NONBLOCK), fops);
if (IS_ERR(file))
goto err;
file->f_mapping = anon_inode_inode->i_mapping;
file->private_data = priv;
return file;
err:
iput(anon_inode_inode);
module_put(fops->owner);
return file;
}
EXPORT_SYMBOL_GPL(anon_inode_getfile);
/**
* anon_inode_getfd - creates a new file instance by hooking it up to an
* anonymous inode, and a dentry that describe the "class"
* of the file
*
* @name: [in] name of the "class" of the new file
* @fops: [in] file operations for the new file
* @priv: [in] private data for the new file (will be file's private_data)
* @flags: [in] flags
*
* Creates a new file by hooking it on a single inode. This is useful for files
* that do not need to have a full-fledged inode in order to operate correctly.
* All the files created with anon_inode_getfd() will share a single inode,
* hence saving memory and avoiding code duplication for the file/inode/dentry
* setup. Returns new descriptor or an error code.
*/
int anon_inode_getfd(const char *name, const struct file_operations *fops,
void *priv, int flags)
{
int error, fd;
struct file *file;
error = get_unused_fd_flags(flags);
if (error < 0)
return error;
fd = error;
file = anon_inode_getfile(name, fops, priv, flags);
if (IS_ERR(file)) {
error = PTR_ERR(file);
goto err_put_unused_fd;
}
fd_install(fd, file);
return fd;
err_put_unused_fd:
put_unused_fd(fd);
return error;
}
EXPORT_SYMBOL_GPL(anon_inode_getfd);
static int __init anon_inode_init(void)
{
anon_inode_mnt = kern_mount(&anon_inode_fs_type);
if (IS_ERR(anon_inode_mnt))
panic("anon_inode_init() kernel mount failed (%ld)\n", PTR_ERR(anon_inode_mnt));
anon_inode_inode = alloc_anon_inode(anon_inode_mnt->mnt_sb);
if (IS_ERR(anon_inode_inode))
panic("anon_inode_init() inode allocation failed (%ld)\n", PTR_ERR(anon_inode_inode));
return 0;
}
fs_initcall(anon_inode_init);
![swh spinner](/static/img/swh-spinner.gif)
Computing file changes ...