Re: [PATCH v13 15/35] fs: Export anon_inode_getfile_secure() for use by KVM

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 11/2/23 17:24, Christian Brauner wrote:
On Fri, Oct 27, 2023 at 11:21:57AM -0700, Sean Christopherson wrote:
Export anon_inode_getfile_secure() so that it can be used by KVM to create
and manage file-based guest memory without need a fullblow filesystem.
The "standard" anon_inode_getfd() doesn't work for KVM's use case as KVM
needs a unique inode for each file, e.g. to be able to independently
manage the size and lifecycle of a given file.

Note, KVM doesn't need a "secure" version, just unique inodes, i.e. ignore
the name.

Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---

Before we enshrine this misleading name let's rename this to:

create_anon_inode_getfile()

I don't claim it's a great name but it's better than *_secure() which is
very confusing. So just:

struct file *create_anon_inode_getfile(const char *name,
                                        const struct file_operations *fops,
                                        void *priv, int flags)

I slightly prefer anon_inode_create_getfile(); grepping include/linux for '\<create_' vs '_create_' shows that this is much more common.

Neither userfaultfd (which uses anon_inode_getfd_secure()) nor io_uring strictly speaking need separate inodes; they do want the call to inode_init_security_anon(). But I agree that the new name is better and I will adjust the comments so that it is clear why you'd use this function instead of anon_inode_get{file,fd}().

May also just remove that context_inode argument from the exported
function. The only other caller is io_uring. And neither it nor this
patchset need the context_inode thing afaict.

True, OTOH we might as well rename anon_inode_getfd_secure() to anon_inode_create_getfd(), and that one does need context_inode.

I'll Cc you on v14 and will carry the patch in my tree.

Paolo

Merge conflict risk is
extremely low so carrying that as part of this patchset is fine and
shouldn't cause huge issues for you.






[Index of Archives]     [Linux Ext4 Filesystem]     [Union Filesystem]     [Filesystem Testing]     [Ceph Users]     [Ecryptfs]     [NTFS 3]     [AutoFS]     [Kernel Newbies]     [Share Photos]     [Security]     [Netfilter]     [Bugtraq]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux Cachefs]     [Reiser Filesystem]     [Linux RAID]     [NTFS 3]     [Samba]     [Device Mapper]     [CEPH Development]

  Powered by Linux