Re: [GIT PULL] Bkl ioctl pushdowns for 2.6.35-rc1

From: Frederic Weisbecker
Date: Thu May 27 2010 - 18:03:56 EST


On Thu, May 27, 2010 at 11:38:24PM +0200, Arnd Bergmann wrote:
> On Saturday 22 May 2010 18:57:05 Frederic Weisbecker wrote:
> > Please pull the bkl/ioctl branch that can be found at:
> >
> > git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing.git
> > bkl/ioctl
> >
> > There are still some pushdowns left, pending for tests or in discussion.
> > I guess ioctl will die for the next merge window.
>
> Let's take a look at the final patch in the meantime. I would suggest merging
> the patch below once all users we care about are done.
>
> Right now, what remains are these trivial users:
>
> | arch/cris/arch-v10/drivers/ds1302.c
> | arch/cris/arch-v10/drivers/gpio.c
> | arch/cris/arch-v10/drivers/i2c.c
> | arch/cris/arch-v10/drivers/pcf8563.c
> | arch/cris/arch-v10/drivers/sync_serial.c
> | arch/cris/arch-v32/drivers/cryptocop.c
> | arch/cris/arch-v32/drivers/i2c.c
> | arch/cris/arch-v32/drivers/mach-a3/gpio.c
> | arch/cris/arch-v32/drivers/mach-fs/gpio.c
> | arch/cris/arch-v32/drivers/pcf8563.c
> | arch/cris/arch-v32/drivers/sync_serial.c
>
> All queued in the cris maintainer tree, but no pull request
> has been sent for 2.6.35 cris.



Not all, I also have a part in my local tree (posted in my last batch):

arch/cris/arch-v10/drivers/gpio.c | 30 ++++++++++++++++++---------
arch/cris/arch-v10/drivers/i2c.c | 24 ++++++++++++++++-----
arch/cris/arch-v10/drivers/sync_serial.c | 32 +++++++++++++++++++---------
arch/cris/arch-v32/drivers/cryptocop.c | 24 ++++++++++++++++-----
arch/cris/arch-v32/drivers/mach-a3/gpio.c | 28 +++++++++++++++++--------
arch/cris/arch-v32/drivers/mach-fs/gpio.c | 29 +++++++++++++++++---------
arch/cris/arch-v32/drivers/sync_serial.c | 30 +++++++++++++++++++--------

I did not include it in the pull request because I hadn't yet the occasion
to build-test it.

I'll do that and try to get this in the cris tree.



>
> | arch/ia64/kernel/perfmon.c
>
> Not sure what happened to this patch. The ioctl function here
> is basically empty, but the patch you did was not merged.



Same problem here: I need to built test it before pushing for good.



> | drivers/media/video/v4l2-dev.c
>
> At least two patches exist, a simple one from me and a
> more complete one from Frederic. Both have been Ack-ed
> by Hans Verkuil, so one of them should just go in.


Yeah, I guess it's too late to integrate the big v4l pushdown
for this merge window.
I'll ping Mauro once -rc1 is released.



> | fs/autofs/root.c
>
> A discussion came up on the naming of the function after
> the patch, and another discussion on when to finally
> kill this driver.



But I won't wait for the driver to be removed though, so I'll
fix the naming issue and queue it soon.



> | fs/logfs/file.c
> | fs/logfs/dir.c
>
> Joern said he had this in his tree, but it was not
> part of the pull request.


At least it's there:
http://git.kernel.org/?p=linux/kernel/git/joern/logfs.git;a=commit;h=ddbb5dd99c40a695d5d75645b5a18bef394acb16




>
> | fs/ecryptfs/file.c
>
> Tyler wanted to take care of this one, it conflicted with
> a bug fix he did. The bug fix should go in anyway, so we should
> just do it the right way (removing the .ioctl version from there)
>
> | sound/oss/dmasound/dmasound_core.c
> | sound/oss/msnd_pinnacle.c
> | sound/oss/au1550_ac97.c
> | sound/oss/sh_dac_audio.c
> | sound/oss/swarm_cs4297a.c
> | sound/oss/vwsnd.c
>
> The patches for this exist but are untested apparently.
> A discussion came up on whether we should just kill oss



Yeah.



>
> Arnd
>
> ---
> [PATCH] Kill ioctl file operation
>
> All instances of the .ioctl() file operation are gone now, so we can
> remove the pointer itself along with the code accessing it.
>
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>



I keep this close for 2.6.36

Thanks.




> ---
>
> Documentation/filesystems/Locking | 8 +-------
> Documentation/filesystems/vfs.txt | 6 +-----
> fs/bad_inode.c | 7 -------
> fs/compat_ioctl.c | 3 +--
> fs/ioctl.c | 18 ++++--------------
> fs/proc/inode.c | 17 ++++-------------
> include/linux/fs.h | 5 ++---
> 7 files changed, 13 insertions(+), 51 deletions(-)
>
> diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking
> index 61c98f0..ea8e1d2 100644
> --- a/Documentation/filesystems/Locking
> +++ b/Documentation/filesystems/Locking
> @@ -372,8 +372,6 @@ prototypes:
> ssize_t (*aio_write) (struct kiocb *, const struct iovec *, unsigned long, loff_t);
> int (*readdir) (struct file *, void *, filldir_t);
> unsigned int (*poll) (struct file *, struct poll_table_struct *);
> - int (*ioctl) (struct inode *, struct file *, unsigned int,
> - unsigned long);
> long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
> long (*compat_ioctl) (struct file *, unsigned int, unsigned long);
> int (*mmap) (struct file *, struct vm_area_struct *);
> @@ -407,8 +405,7 @@ write: no
> aio_write: no
> readdir: no
> poll: no
> -ioctl: yes (see below)
> -unlocked_ioctl: no (see below)
> +unlocked_ioctl: no
> compat_ioctl: no
> mmap: no
> open: no
> @@ -451,9 +448,6 @@ move ->readdir() to inode_operations and use a separate method for directory
> anything that resembles union-mount we won't have a struct file for all
> components. And there are other reasons why the current interface is a mess...
>
> -->ioctl() on regular files is superceded by the ->unlocked_ioctl() that
> -doesn't take the BKL.
> -
> ->read on directories probably must go away - we should just enforce -EISDIR
> in sys_read() and friends.
>
> diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt
> index b668585..caa7989 100644
> --- a/Documentation/filesystems/vfs.txt
> +++ b/Documentation/filesystems/vfs.txt
> @@ -722,7 +722,6 @@ struct file_operations {
> ssize_t (*aio_write) (struct kiocb *, const struct iovec *, unsigned long, loff_t);
> int (*readdir) (struct file *, void *, filldir_t);
> unsigned int (*poll) (struct file *, struct poll_table_struct *);
> - int (*ioctl) (struct inode *, struct file *, unsigned int, unsigned long);
> long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
> long (*compat_ioctl) (struct file *, unsigned int, unsigned long);
> int (*mmap) (struct file *, struct vm_area_struct *);
> @@ -763,10 +762,7 @@ otherwise noted.
> activity on this file and (optionally) go to sleep until there
> is activity. Called by the select(2) and poll(2) system calls
>
> - ioctl: called by the ioctl(2) system call
> -
> - unlocked_ioctl: called by the ioctl(2) system call. Filesystems that do not
> - require the BKL should use this method instead of the ioctl() above.
> + unlocked_ioctl: called by the ioctl(2) system call.
>
> compat_ioctl: called by the ioctl(2) system call when 32 bit system calls
> are used on 64 bit kernels.
> diff --git a/fs/bad_inode.c b/fs/bad_inode.c
> index a05287a..7cb2730 100644
> --- a/fs/bad_inode.c
> +++ b/fs/bad_inode.c
> @@ -55,12 +55,6 @@ static unsigned int bad_file_poll(struct file *filp, poll_table *wait)
> return POLLERR;
> }
>
> -static int bad_file_ioctl (struct inode *inode, struct file *filp,
> - unsigned int cmd, unsigned long arg)
> -{
> - return -EIO;
> -}
> -
> static long bad_file_unlocked_ioctl(struct file *file, unsigned cmd,
> unsigned long arg)
> {
> @@ -160,7 +154,6 @@ static const struct file_operations bad_file_ops =
> .aio_write = bad_file_aio_write,
> .readdir = bad_file_readdir,
> .poll = bad_file_poll,
> - .ioctl = bad_file_ioctl,
> .unlocked_ioctl = bad_file_unlocked_ioctl,
> .compat_ioctl = bad_file_compat_ioctl,
> .mmap = bad_file_mmap,
> diff --git a/fs/compat_ioctl.c b/fs/compat_ioctl.c
> index 641640d..edf72e3 100644
> --- a/fs/compat_ioctl.c
> +++ b/fs/compat_ioctl.c
> @@ -1729,8 +1729,7 @@ asmlinkage long compat_sys_ioctl(unsigned int fd, unsigned int cmd,
> goto out_fput;
> }
>
> - if (!filp->f_op ||
> - (!filp->f_op->ioctl && !filp->f_op->unlocked_ioctl))
> + if (!filp->f_op || !filp->f_op->unlocked_ioctl)
> goto do_ioctl;
> break;
> }
> diff --git a/fs/ioctl.c b/fs/ioctl.c
> index 2d140a7..f855ea4 100644
> --- a/fs/ioctl.c
> +++ b/fs/ioctl.c
> @@ -29,7 +29,6 @@
> * @arg: command-specific argument for ioctl
> *
> * Invokes filesystem specific ->unlocked_ioctl, if one exists; otherwise
> - * invokes filesystem specific ->ioctl method. If neither method exists,
> * returns -ENOTTY.
> *
> * Returns 0 on success, -errno on error.
> @@ -39,21 +38,12 @@ static long vfs_ioctl(struct file *filp, unsigned int cmd,
> {
> int error = -ENOTTY;
>
> - if (!filp->f_op)
> + if (!filp->f_op || !filp->f_op->unlocked_ioctl)
> goto out;
>
> - if (filp->f_op->unlocked_ioctl) {
> - error = filp->f_op->unlocked_ioctl(filp, cmd, arg);
> - if (error == -ENOIOCTLCMD)
> - error = -EINVAL;
> - goto out;
> - } else if (filp->f_op->ioctl) {
> - lock_kernel();
> - error = filp->f_op->ioctl(filp->f_path.dentry->d_inode,
> - filp, cmd, arg);
> - unlock_kernel();
> - }
> -
> + error = filp->f_op->unlocked_ioctl(filp, cmd, arg);
> + if (error == -ENOIOCTLCMD)
> + error = -EINVAL;
> out:
> return error;
> }
> diff --git a/fs/proc/inode.c b/fs/proc/inode.c
> index aea8502..041517c 100644
> --- a/fs/proc/inode.c
> +++ b/fs/proc/inode.c
> @@ -214,8 +214,7 @@ static long proc_reg_unlocked_ioctl(struct file *file, unsigned int cmd, unsigne
> {
> struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode);
> long rv = -ENOTTY;
> - long (*unlocked_ioctl)(struct file *, unsigned int, unsigned long);
> - int (*ioctl)(struct inode *, struct file *, unsigned int, unsigned long);
> + long (*ioctl)(struct file *, unsigned int, unsigned long);
>
> spin_lock(&pde->pde_unload_lock);
> if (!pde->proc_fops) {
> @@ -223,19 +222,11 @@ static long proc_reg_unlocked_ioctl(struct file *file, unsigned int cmd, unsigne
> return rv;
> }
> pde->pde_users++;
> - unlocked_ioctl = pde->proc_fops->unlocked_ioctl;
> - ioctl = pde->proc_fops->ioctl;
> + ioctl = pde->proc_fops->unlocked_ioctl;
> spin_unlock(&pde->pde_unload_lock);
>
> - if (unlocked_ioctl) {
> - rv = unlocked_ioctl(file, cmd, arg);
> - if (rv == -ENOIOCTLCMD)
> - rv = -EINVAL;
> - } else if (ioctl) {
> - WARN_ONCE(1, "Procfs ioctl handlers must use unlocked_ioctl, "
> - "%pf will be called without the Bkl held\n", ioctl);
> - rv = ioctl(file->f_path.dentry->d_inode, file, cmd, arg);
> - }
> + if (ioctl)
> + rv = ioctl(file, cmd, arg);
>
> pde_users_dec(pde);
> return rv;
> diff --git a/include/linux/fs.h b/include/linux/fs.h
> index 85e823a..a92f91c 100644
> --- a/include/linux/fs.h
> +++ b/include/linux/fs.h
> @@ -1478,8 +1478,8 @@ struct block_device_operations;
>
> /*
> * NOTE:
> - * read, write, poll, fsync, readv, writev, unlocked_ioctl and compat_ioctl
> - * can be called without the big kernel lock held in all filesystems.
> + * all file operations except setlease can be called without
> + * the big kernel lock held in all filesystems.
> */
> struct file_operations {
> struct module *owner;
> @@ -1490,7 +1490,6 @@ struct file_operations {
> ssize_t (*aio_write) (struct kiocb *, const struct iovec *, unsigned long, loff_t);
> int (*readdir) (struct file *, void *, filldir_t);
> unsigned int (*poll) (struct file *, struct poll_table_struct *);
> - int (*ioctl) (struct inode *, struct file *, unsigned int, unsigned long);
> long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
> long (*compat_ioctl) (struct file *, unsigned int, unsigned long);
> int (*mmap) (struct file *, struct vm_area_struct *);

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