Commit 0050d7f5 authored by Matthew Wilcox (Oracle)'s avatar Matthew Wilcox (Oracle) Committed by Andrew Morton
Browse files

afs: split afs_pagecache_valid() out of afs_validate() 

For the map_pages() method, we need a test that does not sleep.  The page
fault handler will continue to call the fault() method where we can sleep
and do the full revalidation there.

Link: https://lkml.kernel.org/r/20230327174515.1811532-3-willy@infradead.org


Signed-off-by: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: default avatarDavid Howells <dhowells@redhat.com>
Tested-by: default avatarDavid Howells <dhowells@redhat.com>
Cc: Darrick J. Wong <djwong@kernel.org>
Cc: Dave Chinner <david@fromorbit.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 945ea457

fs/afs/file.c

+2 −12
Original line number Diff line number Diff line
@@ -569,20 +569,10 @@ static void afs_vm_close(struct vm_area_struct *vma) 
static vm_fault_t afs_vm_map_pages(struct vm_fault *vmf, pgoff_t start_pgoff, pgoff_t end_pgoff)

{

	struct afs_vnode *vnode = AFS_FS_I(file_inode(vmf->vma->vm_file));

	struct afs_file *af = vmf->vma->vm_file->private_data;



	switch (afs_validate(vnode, af->key)) {

	case 0:

	if (afs_pagecache_valid(vnode))

		return filemap_map_pages(vmf, start_pgoff, end_pgoff);

	case -ENOMEM:

		return VM_FAULT_OOM;

	case -EINTR:

	case -ERESTARTSYS:

		return VM_FAULT_RETRY;

	case -ESTALE:

	default:

		return VM_FAULT_SIGBUS;

	}

	return 0;

}



static ssize_t afs_file_read_iter(struct kiocb *iocb, struct iov_iter *iter)

fs/afs/inode.c

+19 −8
Original line number Diff line number Diff line
@@ -667,6 +667,24 @@ bool afs_check_validity(struct afs_vnode *vnode) 
	return false;

}



/*

 * Returns true if the pagecache is still valid.  Does not sleep.

 */

bool afs_pagecache_valid(struct afs_vnode *vnode)

{

	if (unlikely(test_bit(AFS_VNODE_DELETED, &vnode->flags))) {

		if (vnode->netfs.inode.i_nlink)

			clear_nlink(&vnode->netfs.inode);

		return true;

	}



	if (test_bit(AFS_VNODE_CB_PROMISED, &vnode->flags) &&

	    afs_check_validity(vnode))

		return true;



	return false;

}



/*

 * validate a vnode/inode

 * - there are several things we need to check
@@ -684,14 +702,7 @@ int afs_validate(struct afs_vnode *vnode, struct key *key) 
	       vnode->fid.vid, vnode->fid.vnode, vnode->flags,

	       key_serial(key));



	if (unlikely(test_bit(AFS_VNODE_DELETED, &vnode->flags))) {

		if (vnode->netfs.inode.i_nlink)

			clear_nlink(&vnode->netfs.inode);

		goto valid;

	}



	if (test_bit(AFS_VNODE_CB_PROMISED, &vnode->flags) &&

	    afs_check_validity(vnode))

	if (afs_pagecache_valid(vnode))

		goto valid;



	down_write(&vnode->validate_lock);

fs/afs/internal.h

+1 −0
Original line number Diff line number Diff line
@@ -1171,6 +1171,7 @@ extern struct inode *afs_iget(struct afs_operation *, struct afs_vnode_param *); 
extern struct inode *afs_root_iget(struct super_block *, struct key *);

extern bool afs_check_validity(struct afs_vnode *);

extern int afs_validate(struct afs_vnode *, struct key *);

bool afs_pagecache_valid(struct afs_vnode *);

extern int afs_getattr(struct mnt_idmap *idmap, const struct path *,

		       struct kstat *, u32, unsigned int);

extern int afs_setattr(struct mnt_idmap *idmap, struct dentry *, struct iattr *);