Re: [PATCH 28/30] fbdev/core: Move file-I/O code into separate file

Sam Ravnborg
2023-06-07T20:48:23Z

Hi Thomas.

On Mon, Jun 05, 2023 at 04:48:10PM +0200, Thomas Zimmermann wrote:
> Move fbdev's file-I/O code into a separate file and contain it in
> init and cleanup helpers. No functional changes.
>
> Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Consider moving the two helps as noted below.
With or without this move:
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>

> ---
> drivers/video/fbdev/core/Makefile | 1 +
> drivers/video/fbdev/core/fb_devfs.c | 484 +++++++++++++++++++++++++
> drivers/video/fbdev/core/fb_internal.h | 6 +
> drivers/video/fbdev/core/fbmem.c | 478 +-----------------------
> 4 files changed, 497 insertions(+), 472 deletions(-)
> create mode 100644 drivers/video/fbdev/core/fb_devfs.c
>
> diff --git a/drivers/video/fbdev/core/Makefile b/drivers/video/fbdev/core/Makefile
> index 665320160f70..125d24f50c36 100644
> --- a/drivers/video/fbdev/core/Makefile
> +++ b/drivers/video/fbdev/core/Makefile
> @@ -2,6 +2,7 @@
> obj-$(CONFIG_FB_NOTIFY) += fb_notify.o
> obj-$(CONFIG_FB) += fb.o
> fb-y := fb_backlight.o \
> + fb_devfs.o \
> fb_info.o \
> fb_procfs.o \
> fbmem.o fbmon.o fbcmap.o fbsysfs.o \
> diff --git a/drivers/video/fbdev/core/fb_devfs.c b/drivers/video/fbdev/core/fb_devfs.c
> new file mode 100644
> index 000000000000..5ab16cb24524
> --- /dev/null
> +++ b/drivers/video/fbdev/core/fb_devfs.c
devfs gives me another understanding of what this file is used for.
fb_ioctl.c?

> @@ -0,0 +1,484 @@
> +// SPDX-License-Identifier: GPL-2.0
> +
> +#include <linux/console.h>
> +#include <linux/fb.h>
> +#include <linux/fbcon.h>
> +#include <linux/major.h>
> +
> +#include "fb_internal.h"
> +
> +/*
> + * We hold a reference to the fb_info in file->private_data,
> + * but if the current registered fb has changed, we don't
> + * actually want to use it.
> + *
> + * So look up the fb_info using the inode minor number,
> + * and just verify it against the reference we have.
> + */
> +static struct fb_info *file_fb_info(struct file *file)
> +{
> + struct inode *inode = file_inode(file);
> + int fbidx = iminor(inode);
> + struct fb_info *info = registered_fb[fbidx];
> +
> + if (info != file->private_data)
> + info = NULL;
> + return info;
> +}
> +
> +static ssize_t fb_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
> +{
> + struct fb_info *info = file_fb_info(file);
> +
> + if (!info)
> + return -ENODEV;
> +
> + if (info->state != FBINFO_STATE_RUNNING)
> + return -EPERM;
> +
> + if (info->fbops->fb_read)
> + return info->fbops->fb_read(info, buf, count, ppos);
> +
> + return fb_io_read(info, buf, count, ppos);
> +}
> +
> +static ssize_t fb_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
> +{
> + struct fb_info *info = file_fb_info(file);
> +
> + if (!info)
> + return -ENODEV;
> +
> + if (info->state != FBINFO_STATE_RUNNING)
> + return -EPERM;
> +
> + if (info->fbops->fb_write)
> + return info->fbops->fb_write(info, buf, count, ppos);
> +
> + return fb_io_write(info, buf, count, ppos);
> +}
> +
> +static long do_fb_ioctl(struct fb_info *info, unsigned int cmd,
> + unsigned long arg)
> +{
> + const struct fb_ops *fb;
> + struct fb_var_screeninfo var;
> + struct fb_fix_screeninfo fix;
> + struct fb_cmap cmap_from;
> + struct fb_cmap_user cmap;
> + void __user *argp = (void __user *)arg;
> + long ret = 0;
> +
> + switch (cmd) {
> + case FBIOGET_VSCREENINFO:
> + lock_fb_info(info);
> + var = info->var;
> + unlock_fb_info(info);
> +
> + ret = copy_to_user(argp, &var, sizeof(var)) ? -EFAULT : 0;
> + break;
> + case FBIOPUT_VSCREENINFO:
> + if (copy_from_user(&var, argp, sizeof(var)))
> + return -EFAULT;
> + /* only for kernel-internal use */
> + var.activate &= ~FB_ACTIVATE_KD_TEXT;
> + console_lock();
> + lock_fb_info(info);
> + ret = fbcon_modechange_possible(info, &var);
> + if (!ret)
> + ret = fb_set_var(info, &var);
> + if (!ret)
> + fbcon_update_vcs(info, var.activate & FB_ACTIVATE_ALL);
> + unlock_fb_info(info);
> + console_unlock();
> + if (!ret && copy_to_user(argp, &var, sizeof(var)))
> + ret = -EFAULT;
> + break;
> + case FBIOGET_FSCREENINFO:
> + lock_fb_info(info);
> + memcpy(&fix, &info->fix, sizeof(fix));
> + if (info->flags & FBINFO_HIDE_SMEM_START)
> + fix.smem_start = 0;
> + unlock_fb_info(info);
> +
> + ret = copy_to_user(argp, &fix, sizeof(fix)) ? -EFAULT : 0;
> + break;
> + case FBIOPUTCMAP:
> + if (copy_from_user(&cmap, argp, sizeof(cmap)))
> + return -EFAULT;
> + ret = fb_set_user_cmap(&cmap, info);
> + break;
> + case FBIOGETCMAP:
> + if (copy_from_user(&cmap, argp, sizeof(cmap)))
> + return -EFAULT;
> + lock_fb_info(info);
> + cmap_from = info->cmap;
> + unlock_fb_info(info);
> + ret = fb_cmap_to_user(&cmap_from, &cmap);
> + break;
> + case FBIOPAN_DISPLAY:
> + if (copy_from_user(&var, argp, sizeof(var)))
> + return -EFAULT;
> + console_lock();
> + lock_fb_info(info);
> + ret = fb_pan_display(info, &var);
> + unlock_fb_info(info);
> + console_unlock();
> + if (ret == 0 && copy_to_user(argp, &var, sizeof(var)))
> + return -EFAULT;
> + break;
> + case FBIO_CURSOR:
> + ret = -EINVAL;
> + break;
> + case FBIOGET_CON2FBMAP:
> + ret = fbcon_get_con2fb_map_ioctl(argp);
> + break;
> + case FBIOPUT_CON2FBMAP:
> + ret = fbcon_set_con2fb_map_ioctl(argp);
> + break;
> + case FBIOBLANK:
> + if (arg > FB_BLANK_POWERDOWN)
> + return -EINVAL;
> + console_lock();
> + lock_fb_info(info);
> + ret = fb_blank(info, arg);
> + /* might again call into fb_blank */
> + fbcon_fb_blanked(info, arg);
> + unlock_fb_info(info);
> + console_unlock();
> + break;
> + default:
> + lock_fb_info(info);
> + fb = info->fbops;
> + if (fb->fb_ioctl)
> + ret = fb->fb_ioctl(info, cmd, arg);
> + else
> + ret = -ENOTTY;
> + unlock_fb_info(info);
> + }
> + return ret;
> +}
> +
> +static long fb_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
> +{
> + struct fb_info *info = file_fb_info(file);
> +
> + if (!info)
> + return -ENODEV;
> + return do_fb_ioctl(info, cmd, arg);
> +}
> +
> +#ifdef CONFIG_COMPAT
> +struct fb_fix_screeninfo32 {
> + char id[16];
> + compat_caddr_t smem_start;
> + u32 smem_len;
> + u32 type;
> + u32 type_aux;
> + u32 visual;
> + u16 xpanstep;
> + u16 ypanstep;
> + u16 ywrapstep;
> + u32 line_length;
> + compat_caddr_t mmio_start;
> + u32 mmio_len;
> + u32 accel;
> + u16 reserved[3];
> +};
> +
> +struct fb_cmap32 {
> + u32 start;
> + u32 len;
> + compat_caddr_t red;
> + compat_caddr_t green;
> + compat_caddr_t blue;
> + compat_caddr_t transp;
> +};
> +
> +static int fb_getput_cmap(struct fb_info *info, unsigned int cmd,
> + unsigned long arg)
> +{
> + struct fb_cmap32 cmap32;
> + struct fb_cmap cmap_from;
> + struct fb_cmap_user cmap;
> +
> + if (copy_from_user(&cmap32, compat_ptr(arg), sizeof(cmap32)))
> + return -EFAULT;
> +
> + cmap = (struct fb_cmap_user) {
> + .start = cmap32.start,
> + .len = cmap32.len,
> + .red = compat_ptr(cmap32.red),
> + .green = compat_ptr(cmap32.green),
> + .blue = compat_ptr(cmap32.blue),
> + .transp = compat_ptr(cmap32.transp),
> + };
> +
> + if (cmd == FBIOPUTCMAP)
> + return fb_set_user_cmap(&cmap, info);
> +
> + lock_fb_info(info);
> + cmap_from = info->cmap;
> + unlock_fb_info(info);
> +
> + return fb_cmap_to_user(&cmap_from, &cmap);
> +}
> +
> +static int do_fscreeninfo_to_user(struct fb_fix_screeninfo *fix,
> + struct fb_fix_screeninfo32 __user *fix32)
> +{
> + __u32 data;
> + int err;
> +
> + err = copy_to_user(&fix32->id, &fix->id, sizeof(fix32->id));
> +
> + data = (__u32) (unsigned long) fix->smem_start;
> + err |= put_user(data, &fix32->smem_start);
> +
> + err |= put_user(fix->smem_len, &fix32->smem_len);
> + err |= put_user(fix->type, &fix32->type);
> + err |= put_user(fix->type_aux, &fix32->type_aux);
> + err |= put_user(fix->visual, &fix32->visual);
> + err |= put_user(fix->xpanstep, &fix32->xpanstep);
> + err |= put_user(fix->ypanstep, &fix32->ypanstep);
> + err |= put_user(fix->ywrapstep, &fix32->ywrapstep);
> + err |= put_user(fix->line_length, &fix32->line_length);
> +
> + data = (__u32) (unsigned long) fix->mmio_start;
> + err |= put_user(data, &fix32->mmio_start);
> +
> + err |= put_user(fix->mmio_len, &fix32->mmio_len);
> + err |= put_user(fix->accel, &fix32->accel);
> + err |= copy_to_user(fix32->reserved, fix->reserved,
> + sizeof(fix->reserved));
> +
> + if (err)
> + return -EFAULT;
> + return 0;
> +}
> +
> +static int fb_get_fscreeninfo(struct fb_info *info, unsigned int cmd,
> + unsigned long arg)
> +{
> + struct fb_fix_screeninfo fix;
> +
> + lock_fb_info(info);
> + fix = info->fix;
> + if (info->flags & FBINFO_HIDE_SMEM_START)
> + fix.smem_start = 0;
> + unlock_fb_info(info);
> + return do_fscreeninfo_to_user(&fix, compat_ptr(arg));
> +}
> +
> +static long fb_compat_ioctl(struct file *file, unsigned int cmd,
> + unsigned long arg)
> +{
> + struct fb_info *info = file_fb_info(file);
> + const struct fb_ops *fb;
> + long ret = -ENOIOCTLCMD;
> +
> + if (!info)
> + return -ENODEV;
> + fb = info->fbops;
> + switch (cmd) {
> + case FBIOGET_VSCREENINFO:
> + case FBIOPUT_VSCREENINFO:
> + case FBIOPAN_DISPLAY:
> + case FBIOGET_CON2FBMAP:
> + case FBIOPUT_CON2FBMAP:
> + arg = (unsigned long) compat_ptr(arg);
> + fallthrough;
> + case FBIOBLANK:
> + ret = do_fb_ioctl(info, cmd, arg);
> + break;
> +
> + case FBIOGET_FSCREENINFO:
> + ret = fb_get_fscreeninfo(info, cmd, arg);
> + break;
> +
> + case FBIOGETCMAP:
> + case FBIOPUTCMAP:
> + ret = fb_getput_cmap(info, cmd, arg);
> + break;
> +
> + default:
> + if (fb->fb_compat_ioctl)
> + ret = fb->fb_compat_ioctl(info, cmd, arg);
> + break;
> + }
> + return ret;
> +}
> +#endif
> +
> +static int fb_mmap(struct file *file, struct vm_area_struct *vma)
> +{
> + struct fb_info *info = file_fb_info(file);
> + unsigned long mmio_pgoff;
> + unsigned long start;
> + u32 len;
> +
> + if (!info)
> + return -ENODEV;
> + mutex_lock(&info->mm_lock);
> +
> + if (info->fbops->fb_mmap) {
> + int res;
> +
> + /*
> + * The framebuffer needs to be accessed decrypted, be sure
> + * SME protection is removed ahead of the call
> + */
> + vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);
> + res = info->fbops->fb_mmap(info, vma);
> + mutex_unlock(&info->mm_lock);
> + return res;
> +#if IS_ENABLED(CONFIG_FB_DEFERRED_IO)
> + } else if (info->fbdefio) {
> + /*
> + * FB deferred I/O wants you to handle mmap in your drivers. At a
> + * minimum, point struct fb_ops.fb_mmap to fb_deferred_io_mmap().
> + */
> + dev_warn_once(info->dev, "fbdev mmap not set up for deferred I/O.\n");
> + mutex_unlock(&info->mm_lock);
> + return -ENODEV;
> +#endif
> + }
> +
> + /*
> + * Ugh. This can be either the frame buffer mapping, or
> + * if pgoff points past it, the mmio mapping.
> + */
> + start = info->fix.smem_start;
> + len = info->fix.smem_len;
> + mmio_pgoff = PAGE_ALIGN((start & ~PAGE_MASK) + len) >> PAGE_SHIFT;
> + if (vma->vm_pgoff >= mmio_pgoff) {
> + if (info->var.accel_flags) {
> + mutex_unlock(&info->mm_lock);
> + return -EINVAL;
> + }
> +
> + vma->vm_pgoff -= mmio_pgoff;
> + start = info->fix.mmio_start;
> + len = info->fix.mmio_len;
> + }
> + mutex_unlock(&info->mm_lock);
> +
> + vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
> + fb_pgprotect(file, vma, start);
> +
> + return vm_iomap_memory(vma, start, len);
> +}
> +
> +static int fb_open(struct inode *inode, struct file *file)
> +__acquires(&info->lock)
> +__releases(&info->lock)
> +{
> + int fbidx = iminor(inode);
> + struct fb_info *info;
> + int res = 0;
> +
> + info = get_fb_info(fbidx);
> + if (!info) {
> + request_module("fb%d", fbidx);
> + info = get_fb_info(fbidx);
> + if (!info)
> + return -ENODEV;
> + }
> + if (IS_ERR(info))
> + return PTR_ERR(info);
> +
> + lock_fb_info(info);
> + if (!try_module_get(info->fbops->owner)) {
> + res = -ENODEV;
> + goto out;
> + }
> + file->private_data = info;
> + if (info->fbops->fb_open) {
> + res = info->fbops->fb_open(info, 1);
> + if (res)
> + module_put(info->fbops->owner);
> + }
> +#ifdef CONFIG_FB_DEFERRED_IO
> + if (info->fbdefio)
> + fb_deferred_io_open(info, inode, file);
> +#endif
> +out:
> + unlock_fb_info(info);
> + if (res)
> + put_fb_info(info);
> + return res;
> +}
> +
> +static int fb_release(struct inode *inode, struct file *file)
> +__acquires(&info->lock)
> +__releases(&info->lock)
> +{
> + struct fb_info * const info = file->private_data;
> +
> + lock_fb_info(info);
> +#if IS_ENABLED(CONFIG_FB_DEFERRED_IO)
> + if (info->fbdefio)
> + fb_deferred_io_release(info);
> +#endif
> + if (info->fbops->fb_release)
> + info->fbops->fb_release(info, 1);
> + module_put(info->fbops->owner);
> + unlock_fb_info(info);
> + put_fb_info(info);
> + return 0;
> +}
> +
> +#if defined(CONFIG_FB_PROVIDE_GET_FB_UNMAPPED_AREA) && !defined(CONFIG_MMU)
> +static unsigned long get_fb_unmapped_area(struct file *filp,
> + unsigned long addr, unsigned long len,
> + unsigned long pgoff, unsigned long flags)
> +{
> + struct fb_info * const info = filp->private_data;
> + unsigned long fb_size = PAGE_ALIGN(info->fix.smem_len);
> +
> + if (pgoff > fb_size || len > fb_size - pgoff)
> + return -EINVAL;
> +
> + return (unsigned long)info->screen_base + pgoff;
> +}
> +#endif
> +
> +static const struct file_operations fb_fops = {
> + .owner = THIS_MODULE,
> + .read = fb_read,
> + .write = fb_write,
> + .unlocked_ioctl = fb_ioctl,
> +#ifdef CONFIG_COMPAT
> + .compat_ioctl = fb_compat_ioctl,
> +#endif
> + .mmap = fb_mmap,
> + .open = fb_open,
> + .release = fb_release,
> +#if defined(HAVE_ARCH_FB_UNMAPPED_AREA) || \
> + (defined(CONFIG_FB_PROVIDE_GET_FB_UNMAPPED_AREA) && \
> + !defined(CONFIG_MMU))
> + .get_unmapped_area = get_fb_unmapped_area,
> +#endif
> +#ifdef CONFIG_FB_DEFERRED_IO
> + .fsync = fb_deferred_io_fsync,
> +#endif
> + .llseek = default_llseek,
> +};
> +
> +int fb_register_chrdev(void)
> +{
> + int ret;
> +
> + ret = register_chrdev(FB_MAJOR, "fb", &fb_fops);
> + if (ret) {
> + pr_err("Unable to get major %d for fb devs\n", FB_MAJOR);
> + return ret;
> + }
> +
> + return ret;
> +}
> +
> +void fb_unregister_chrdev(void)
> +{
> + unregister_chrdev(FB_MAJOR, "fb");
> +}
> diff --git a/drivers/video/fbdev/core/fb_internal.h b/drivers/video/fbdev/core/fb_internal.h
> index 51f7c9f04e45..abe06c9da36e 100644
> --- a/drivers/video/fbdev/core/fb_internal.h
> +++ b/drivers/video/fbdev/core/fb_internal.h
> @@ -6,10 +6,16 @@
> #include <linux/fb.h>
> #include <linux/mutex.h>
>
> +/* fb_devfs.c */
> +int fb_register_chrdev(void);
> +void fb_unregister_chrdev(void);
> +
> /* fbmem.c */
> extern struct mutex registration_lock;
> extern struct fb_info *registered_fb[FB_MAX];
> extern int num_registered_fb;
> +struct fb_info *get_fb_info(unsigned int idx);
> +void put_fb_info(struct fb_info *fb_info);
The only users of get_fb_info() and put_fb_info() are now in fb_devfs.
So consider moving these two helpers too.

>
> /* fb_procfs.c */
> int fb_init_procfs(void);
> diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c
> index de1e45240161..2d26ac46337b 100644
> --- a/drivers/video/fbdev/core/fbmem.c
> +++ b/drivers/video/fbdev/core/fbmem.c
> @@ -17,7 +17,6 @@
> #include <linux/types.h>
> #include <linux/errno.h>
> #include <linux/kernel.h>
> -#include <linux/major.h>
> #include <linux/slab.h>
> #include <linux/mm.h>
> #include <linux/mman.h>
> @@ -54,7 +53,7 @@ bool fb_center_logo __read_mostly;
>
> int fb_logo_count __read_mostly = -1;
>
> -static struct fb_info *get_fb_info(unsigned int idx)
> +struct fb_info *get_fb_info(unsigned int idx)
> {
> struct fb_info *fb_info;
>
> @@ -70,7 +69,7 @@ static struct fb_info *get_fb_info(unsigned int idx)
> return fb_info;
> }
>
> -static void put_fb_info(struct fb_info *fb_info)
> +void put_fb_info(struct fb_info *fb_info)
> {
> if (!refcount_dec_and_test(&fb_info->count))
> return;
> @@ -699,59 +698,6 @@ int fb_show_logo(struct fb_info *info, int rotate) { return 0; }
> EXPORT_SYMBOL(fb_prepare_logo);
> EXPORT_SYMBOL(fb_show_logo);

Reminds me - consider moving logo stuff to a fb_logo file.
This would reduce fbmem with a lot of lines, and it is separate.
But it is outside the goal of this patchset.

>
> -/*
> - * We hold a reference to the fb_info in file->private_data,
> - * but if the current registered fb has changed, we don't
> - * actually want to use it.
> - *
> - * So look up the fb_info using the inode minor number,
> - * and just verify it against the reference we have.
> - */
> -static struct fb_info *file_fb_info(struct file *file)
> -{
> - struct inode *inode = file_inode(file);
> - int fbidx = iminor(inode);
> - struct fb_info *info = registered_fb[fbidx];
> -
> - if (info != file->private_data)
> - info = NULL;
> - return info;
> -}
> -
> -static ssize_t
> -fb_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
> -{
> - struct fb_info *info = file_fb_info(file);
> -
> - if (!info)
> - return -ENODEV;
> -
> - if (info->state != FBINFO_STATE_RUNNING)
> - return -EPERM;
> -
> - if (info->fbops->fb_read)
> - return info->fbops->fb_read(info, buf, count, ppos);
> -
> - return fb_io_read(info, buf, count, ppos);
> -}
> -
> -static ssize_t
> -fb_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
> -{
> - struct fb_info *info = file_fb_info(file);
> -
> - if (!info)
> - return -ENODEV;
> -
> - if (info->state != FBINFO_STATE_RUNNING)
> - return -EPERM;
> -
> - if (info->fbops->fb_write)
> - return info->fbops->fb_write(info, buf, count, ppos);
> -
> - return fb_io_write(info, buf, count, ppos);
> -}
> -
> int
> fb_pan_display(struct fb_info *info, struct fb_var_screeninfo *var)
> {
> @@ -951,416 +897,6 @@ fb_blank(struct fb_info *info, int blank)
> }
> EXPORT_SYMBOL(fb_blank);
>
> -static long do_fb_ioctl(struct fb_info *info, unsigned int cmd,
> - unsigned long arg)
> -{
> - const struct fb_ops *fb;
> - struct fb_var_screeninfo var;
> - struct fb_fix_screeninfo fix;
> - struct fb_cmap cmap_from;
> - struct fb_cmap_user cmap;
> - void __user *argp = (void __user *)arg;
> - long ret = 0;
> -
> - switch (cmd) {
> - case FBIOGET_VSCREENINFO:
> - lock_fb_info(info);
> - var = info->var;
> - unlock_fb_info(info);
> -
> - ret = copy_to_user(argp, &var, sizeof(var)) ? -EFAULT : 0;
> - break;
> - case FBIOPUT_VSCREENINFO:
> - if (copy_from_user(&var, argp, sizeof(var)))
> - return -EFAULT;
> - /* only for kernel-internal use */
> - var.activate &= ~FB_ACTIVATE_KD_TEXT;
> - console_lock();
> - lock_fb_info(info);
> - ret = fbcon_modechange_possible(info, &var);
> - if (!ret)
> - ret = fb_set_var(info, &var);
> - if (!ret)
> - fbcon_update_vcs(info, var.activate & FB_ACTIVATE_ALL);
> - unlock_fb_info(info);
> - console_unlock();
> - if (!ret && copy_to_user(argp, &var, sizeof(var)))
> - ret = -EFAULT;
> - break;
> - case FBIOGET_FSCREENINFO:
> - lock_fb_info(info);
> - memcpy(&fix, &info->fix, sizeof(fix));
> - if (info->flags & FBINFO_HIDE_SMEM_START)
> - fix.smem_start = 0;
> - unlock_fb_info(info);
> -
> - ret = copy_to_user(argp, &fix, sizeof(fix)) ? -EFAULT : 0;
> - break;
> - case FBIOPUTCMAP:
> - if (copy_from_user(&cmap, argp, sizeof(cmap)))
> - return -EFAULT;
> - ret = fb_set_user_cmap(&cmap, info);
> - break;
> - case FBIOGETCMAP:
> - if (copy_from_user(&cmap, argp, sizeof(cmap)))
> - return -EFAULT;
> - lock_fb_info(info);
> - cmap_from = info->cmap;
> - unlock_fb_info(info);
> - ret = fb_cmap_to_user(&cmap_from, &cmap);
> - break;
> - case FBIOPAN_DISPLAY:
> - if (copy_from_user(&var, argp, sizeof(var)))
> - return -EFAULT;
> - console_lock();
> - lock_fb_info(info);
> - ret = fb_pan_display(info, &var);
> - unlock_fb_info(info);
> - console_unlock();
> - if (ret == 0 && copy_to_user(argp, &var, sizeof(var)))
> - return -EFAULT;
> - break;
> - case FBIO_CURSOR:
> - ret = -EINVAL;
> - break;
> - case FBIOGET_CON2FBMAP:
> - ret = fbcon_get_con2fb_map_ioctl(argp);
> - break;
> - case FBIOPUT_CON2FBMAP:
> - ret = fbcon_set_con2fb_map_ioctl(argp);
> - break;
> - case FBIOBLANK:
> - if (arg > FB_BLANK_POWERDOWN)
> - return -EINVAL;
> - console_lock();
> - lock_fb_info(info);
> - ret = fb_blank(info, arg);
> - /* might again call into fb_blank */
> - fbcon_fb_blanked(info, arg);
> - unlock_fb_info(info);
> - console_unlock();
> - break;
> - default:
> - lock_fb_info(info);
> - fb = info->fbops;
> - if (fb->fb_ioctl)
> - ret = fb->fb_ioctl(info, cmd, arg);
> - else
> - ret = -ENOTTY;
> - unlock_fb_info(info);
> - }
> - return ret;
> -}
> -
> -static long fb_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
> -{
> - struct fb_info *info = file_fb_info(file);
> -
> - if (!info)
> - return -ENODEV;
> - return do_fb_ioctl(info, cmd, arg);
> -}
> -
> -#ifdef CONFIG_COMPAT
> -struct fb_fix_screeninfo32 {
> - char id[16];
> - compat_caddr_t smem_start;
> - u32 smem_len;
> - u32 type;
> - u32 type_aux;
> - u32 visual;
> - u16 xpanstep;
> - u16 ypanstep;
> - u16 ywrapstep;
> - u32 line_length;
> - compat_caddr_t mmio_start;
> - u32 mmio_len;
> - u32 accel;
> - u16 reserved[3];
> -};
> -
> -struct fb_cmap32 {
> - u32 start;
> - u32 len;
> - compat_caddr_t red;
> - compat_caddr_t green;
> - compat_caddr_t blue;
> - compat_caddr_t transp;
> -};
> -
> -static int fb_getput_cmap(struct fb_info *info, unsigned int cmd,
> - unsigned long arg)
> -{
> - struct fb_cmap32 cmap32;
> - struct fb_cmap cmap_from;
> - struct fb_cmap_user cmap;
> -
> - if (copy_from_user(&cmap32, compat_ptr(arg), sizeof(cmap32)))
> - return -EFAULT;
> -
> - cmap = (struct fb_cmap_user) {
> - .start = cmap32.start,
> - .len = cmap32.len,
> - .red = compat_ptr(cmap32.red),
> - .green = compat_ptr(cmap32.green),
> - .blue = compat_ptr(cmap32.blue),
> - .transp = compat_ptr(cmap32.transp),
> - };
> -
> - if (cmd == FBIOPUTCMAP)
> - return fb_set_user_cmap(&cmap, info);
> -
> - lock_fb_info(info);
> - cmap_from = info->cmap;
> - unlock_fb_info(info);
> -
> - return fb_cmap_to_user(&cmap_from, &cmap);
> -}
> -
> -static int do_fscreeninfo_to_user(struct fb_fix_screeninfo *fix,
> - struct fb_fix_screeninfo32 __user *fix32)
> -{
> - __u32 data;
> - int err;
> -
> - err = copy_to_user(&fix32->id, &fix->id, sizeof(fix32->id));
> -
> - data = (__u32) (unsigned long) fix->smem_start;
> - err |= put_user(data, &fix32->smem_start);
> -
> - err |= put_user(fix->smem_len, &fix32->smem_len);
> - err |= put_user(fix->type, &fix32->type);
> - err |= put_user(fix->type_aux, &fix32->type_aux);
> - err |= put_user(fix->visual, &fix32->visual);
> - err |= put_user(fix->xpanstep, &fix32->xpanstep);
> - err |= put_user(fix->ypanstep, &fix32->ypanstep);
> - err |= put_user(fix->ywrapstep, &fix32->ywrapstep);
> - err |= put_user(fix->line_length, &fix32->line_length);
> -
> - data = (__u32) (unsigned long) fix->mmio_start;
> - err |= put_user(data, &fix32->mmio_start);
> -
> - err |= put_user(fix->mmio_len, &fix32->mmio_len);
> - err |= put_user(fix->accel, &fix32->accel);
> - err |= copy_to_user(fix32->reserved, fix->reserved,
> - sizeof(fix->reserved));
> -
> - if (err)
> - return -EFAULT;
> - return 0;
> -}
> -
> -static int fb_get_fscreeninfo(struct fb_info *info, unsigned int cmd,
> - unsigned long arg)
> -{
> - struct fb_fix_screeninfo fix;
> -
> - lock_fb_info(info);
> - fix = info->fix;
> - if (info->flags & FBINFO_HIDE_SMEM_START)
> - fix.smem_start = 0;
> - unlock_fb_info(info);
> - return do_fscreeninfo_to_user(&fix, compat_ptr(arg));
> -}
> -
> -static long fb_compat_ioctl(struct file *file, unsigned int cmd,
> - unsigned long arg)
> -{
> - struct fb_info *info = file_fb_info(file);
> - const struct fb_ops *fb;
> - long ret = -ENOIOCTLCMD;
> -
> - if (!info)
> - return -ENODEV;
> - fb = info->fbops;
> - switch(cmd) {
> - case FBIOGET_VSCREENINFO:
> - case FBIOPUT_VSCREENINFO:
> - case FBIOPAN_DISPLAY:
> - case FBIOGET_CON2FBMAP:
> - case FBIOPUT_CON2FBMAP:
> - arg = (unsigned long) compat_ptr(arg);
> - fallthrough;
> - case FBIOBLANK:
> - ret = do_fb_ioctl(info, cmd, arg);
> - break;
> -
> - case FBIOGET_FSCREENINFO:
> - ret = fb_get_fscreeninfo(info, cmd, arg);
> - break;
> -
> - case FBIOGETCMAP:
> - case FBIOPUTCMAP:
> - ret = fb_getput_cmap(info, cmd, arg);
> - break;
> -
> - default:
> - if (fb->fb_compat_ioctl)
> - ret = fb->fb_compat_ioctl(info, cmd, arg);
> - break;
> - }
> - return ret;
> -}
> -#endif
> -
> -static int
> -fb_mmap(struct file *file, struct vm_area_struct * vma)
> -{
> - struct fb_info *info = file_fb_info(file);
> - unsigned long mmio_pgoff;
> - unsigned long start;
> - u32 len;
> -
> - if (!info)
> - return -ENODEV;
> - mutex_lock(&info->mm_lock);
> -
> - if (info->fbops->fb_mmap) {
> - int res;
> -
> - /*
> - * The framebuffer needs to be accessed decrypted, be sure
> - * SME protection is removed ahead of the call
> - */
> - vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);
> - res = info->fbops->fb_mmap(info, vma);
> - mutex_unlock(&info->mm_lock);
> - return res;
> -#if IS_ENABLED(CONFIG_FB_DEFERRED_IO)
> - } else if (info->fbdefio) {
> - /*
> - * FB deferred I/O wants you to handle mmap in your drivers. At a
> - * minimum, point struct fb_ops.fb_mmap to fb_deferred_io_mmap().
> - */
> - dev_warn_once(info->dev, "fbdev mmap not set up for deferred I/O.\n");
> - mutex_unlock(&info->mm_lock);
> - return -ENODEV;
> -#endif
> - }
> -
> - /*
> - * Ugh. This can be either the frame buffer mapping, or
> - * if pgoff points past it, the mmio mapping.
> - */
> - start = info->fix.smem_start;
> - len = info->fix.smem_len;
> - mmio_pgoff = PAGE_ALIGN((start & ~PAGE_MASK) + len) >> PAGE_SHIFT;
> - if (vma->vm_pgoff >= mmio_pgoff) {
> - if (info->var.accel_flags) {
> - mutex_unlock(&info->mm_lock);
> - return -EINVAL;
> - }
> -
> - vma->vm_pgoff -= mmio_pgoff;
> - start = info->fix.mmio_start;
> - len = info->fix.mmio_len;
> - }
> - mutex_unlock(&info->mm_lock);
> -
> - vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
> - fb_pgprotect(file, vma, start);
> -
> - return vm_iomap_memory(vma, start, len);
> -}
> -
> -static int
> -fb_open(struct inode *inode, struct file *file)
> -__acquires(&info->lock)
> -__releases(&info->lock)
> -{
> - int fbidx = iminor(inode);
> - struct fb_info *info;
> - int res = 0;
> -
> - info = get_fb_info(fbidx);
> - if (!info) {
> - request_module("fb%d", fbidx);
> - info = get_fb_info(fbidx);
> - if (!info)
> - return -ENODEV;
> - }
> - if (IS_ERR(info))
> - return PTR_ERR(info);
> -
> - lock_fb_info(info);
> - if (!try_module_get(info->fbops->owner)) {
> - res = -ENODEV;
> - goto out;
> - }
> - file->private_data = info;
> - if (info->fbops->fb_open) {
> - res = info->fbops->fb_open(info,1);
> - if (res)
> - module_put(info->fbops->owner);
> - }
> -#ifdef CONFIG_FB_DEFERRED_IO
> - if (info->fbdefio)
> - fb_deferred_io_open(info, inode, file);
> -#endif
> -out:
> - unlock_fb_info(info);
> - if (res)
> - put_fb_info(info);
> - return res;
> -}
> -
> -static int
> -fb_release(struct inode *inode, struct file *file)
> -__acquires(&info->lock)
> -__releases(&info->lock)
> -{
> - struct fb_info * const info = file->private_data;
> -
> - lock_fb_info(info);
> -#if IS_ENABLED(CONFIG_FB_DEFERRED_IO)
> - if (info->fbdefio)
> - fb_deferred_io_release(info);
> -#endif
> - if (info->fbops->fb_release)
> - info->fbops->fb_release(info,1);
> - module_put(info->fbops->owner);
> - unlock_fb_info(info);
> - put_fb_info(info);
> - return 0;
> -}
> -
> -#if defined(CONFIG_FB_PROVIDE_GET_FB_UNMAPPED_AREA) && !defined(CONFIG_MMU)
> -static unsigned long get_fb_unmapped_area(struct file *filp,
> - unsigned long addr, unsigned long len,
> - unsigned long pgoff, unsigned long flags)
> -{
> - struct fb_info * const info = filp->private_data;
> - unsigned long fb_size = PAGE_ALIGN(info->fix.smem_len);
> -
> - if (pgoff > fb_size || len > fb_size - pgoff)
> - return -EINVAL;
> -
> - return (unsigned long)info->screen_base + pgoff;
> -}
> -#endif
> -
> -static const struct file_operations fb_fops = {
> - .owner = THIS_MODULE,
> - .read = fb_read,
> - .write = fb_write,
> - .unlocked_ioctl = fb_ioctl,
> -#ifdef CONFIG_COMPAT
> - .compat_ioctl = fb_compat_ioctl,
> -#endif
> - .mmap = fb_mmap,
> - .open = fb_open,
> - .release = fb_release,
> -#if defined(HAVE_ARCH_FB_UNMAPPED_AREA) || \
> - (defined(CONFIG_FB_PROVIDE_GET_FB_UNMAPPED_AREA) && \
> - !defined(CONFIG_MMU))
> - .get_unmapped_area = get_fb_unmapped_area,
> -#endif
> -#ifdef CONFIG_FB_DEFERRED_IO
> - .fsync = fb_deferred_io_fsync,
> -#endif
> - .llseek = default_llseek,
> -};
> -
> struct class *fb_class;
> EXPORT_SYMBOL(fb_class);
>
> @@ -1588,11 +1124,9 @@ fbmem_init(void)
> if (ret)
> return ret;
>
> - ret = register_chrdev(FB_MAJOR, "fb", &fb_fops);
> - if (ret) {
> - printk("unable to get major %d for fb devs\n", FB_MAJOR);
> + ret = fb_register_chrdev();
> + if (ret)
> goto err_chrdev;
> - }
>
> fb_class = class_create("graphics");
> if (IS_ERR(fb_class)) {
> @@ -1607,7 +1141,7 @@ fbmem_init(void)
> return 0;
>
> err_class:
> - unregister_chrdev(FB_MAJOR, "fb");
> + fb_unregister_chrdev();
> err_chrdev:
> fb_cleanup_procfs();
> return ret;
> @@ -1622,7 +1156,7 @@ fbmem_exit(void)
>
> fb_cleanup_procfs();
> class_destroy(fb_class);
> - unregister_chrdev(FB_MAJOR, "fb");
> + fb_unregister_chrdev();
> }
>
> module_exit(fbmem_exit);
> --
> 2.40.1