Re: [patch 1/3] split mmap

[Peter Zijlstra <a.p.zijlstra@chello.nl>]

On Sat, 2007-03-24 at 23:07 +0100, Miklos Szeredi wrote:
> From: Miklos Szeredi <mszeredi@suse.cz>
> 
> This is a straightforward split of do_mmap_pgoff() into two functions:
> 
>  - do_mmap_pgoff() checks the parameters, and calculates the vma
>    flags.  Then it calls
> 
>  - mmap_region(), which does the actual mapping
> 
> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>

Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>

> ---
> 
> Index: linux/mm/mmap.c
> ===================================================================
> --- linux.orig/mm/mmap.c	2007-03-24 21:00:40.000000000 +0100
> +++ linux/mm/mmap.c	2007-03-24 22:28:52.000000000 +0100
> @@ -893,14 +893,11 @@ unsigned long do_mmap_pgoff(struct file 
>  			unsigned long flags, unsigned long pgoff)
>  {
>  	struct mm_struct * mm = current->mm;
> -	struct vm_area_struct * vma, * prev;
>  	struct inode *inode;
>  	unsigned int vm_flags;
> -	int correct_wcount = 0;
>  	int error;
> -	struct rb_node ** rb_link, * rb_parent;
>  	int accountable = 1;
> -	unsigned long charged = 0, reqprot = prot;
> +	unsigned long reqprot = prot;
>  
>  	/*
>  	 * Does the application expect PROT_READ to imply PROT_EXEC?
> @@ -1025,7 +1022,25 @@ unsigned long do_mmap_pgoff(struct file 
>  	error = security_file_mmap(file, reqprot, prot, flags);
>  	if (error)
>  		return error;
> -		
> +
> +	return mmap_region(file, addr, len, flags, vm_flags, pgoff,
> +			   accountable);
> +}
> +EXPORT_SYMBOL(do_mmap_pgoff);
> +
> +unsigned long mmap_region(struct file *file, unsigned long addr,
> +			  unsigned long len, unsigned long flags,
> +			  unsigned int vm_flags, unsigned long pgoff,
> +			  int accountable)
> +{
> +	struct mm_struct *mm = current->mm;
> +	struct vm_area_struct *vma, *prev;
> +	int correct_wcount = 0;
> +	int error;
> +	struct rb_node **rb_link, *rb_parent;
> +	unsigned long charged = 0;
> +	struct inode *inode =  file ? file->f_path.dentry->d_inode : NULL;
> +
>  	/* Clear old maps */
>  	error = -ENOMEM;
>  munmap_back:
> @@ -1174,8 +1189,6 @@ unacct_error:
>  	return error;
>  }
>  
> -EXPORT_SYMBOL(do_mmap_pgoff);
> -
>  /* Get an address range which is currently unmapped.
>   * For shmat() with addr=0.
>   *
> Index: linux/include/linux/mm.h
> ===================================================================
> --- linux.orig/include/linux/mm.h	2007-03-24 21:00:40.000000000 +0100
> +++ linux/include/linux/mm.h	2007-03-24 22:28:52.000000000 +0100
> @@ -1035,6 +1035,10 @@ extern unsigned long get_unmapped_area(s
>  extern unsigned long do_mmap_pgoff(struct file *file, unsigned long addr,
>  	unsigned long len, unsigned long prot,
>  	unsigned long flag, unsigned long pgoff);
> +extern unsigned long mmap_region(struct file *file, unsigned long addr,
> +	unsigned long len, unsigned long flags,
> +	unsigned int vm_flags, unsigned long pgoff,
> +	int accountable);
>  
>  static inline unsigned long do_mmap(struct file *file, unsigned long addr,
>  	unsigned long len, unsigned long prot,