lkml.org 
[lkml]   [2012]   [Jun]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v3 5/6] KVM: introduce gfn_to_hva_read/kvm_read_hva/kvm_read_hva_atomic
On 06/18/2012 06:16 PM, Avi Kivity wrote:

> On 06/12/2012 05:48 AM, Xiao Guangrong wrote:
>> This set of functions is only used to read data from host space, read is
>> a special case in the later patch
>>
>>
>> +/*
>> + * The hva returned by this function is only allowed to be read.
>> + * It should pair with kvm_read_hva() or kvm_read_hva_atomic().
>> + */
>> +static unsigned long gfn_to_hva_read(struct kvm *kvm, gfn_t gfn)
>> +{
>> + return gfn_to_hva_many(gfn_to_memslot(kvm, gfn), gfn, NULL);
>> +}
>> +
>> +static int kvm_read_hva(void *data, void *hva, int len)
>> +{
>> + return __copy_from_user(data, (void __user *)hva, len);
>> +
>> +}
>> +
>> +static int kvm_read_hva_atomic(void *data, void *hva, int len)
>> +{
>> + return __copy_from_user_inatomic(data, (void __user *)hva, len);
>> +
>> +}
>
> Why cast to __user? Make it __user in the first place.
>


Okay.

> Also these are just simple wrappers, why to them at all?


For gfn_to_hva_read(), they will call gfn_to_hva_many(...write = false)
in the later patch.

For kvm_read_hva() and kvm_read_hva_atomic(), they are pure wrappers,
i think its name is a good hint to let gfn_to_hva_read to pair with
kvm_read_hva()/kvm_read_hva_atomic().



\
 
 \ /
  Last update: 2012-06-19 05:01    [W:1.635 / U:0.048 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site