diff options
| author | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2016-03-08 13:53:35 +0300 |
|---|---|---|
| committer | Christian Borntraeger <borntraeger@de.ibm.com> | 2016-06-10 13:07:27 +0300 |
| commit | d3ed1ceeace311af9973d17a07a114bfaf0ca1b1 (patch) | |
| tree | 1e9a353c769d89bf8eee9489f931869dcaf0651a /arch/s390/kvm/kvm-s390.c | |
| parent | c427c42cd612719e8fb8b5891cc9761e7770024e (diff) | |
| download | linux-d3ed1ceeace311af9973d17a07a114bfaf0ca1b1.tar.xz | |
s390/mm: set and get guest storage key mmap locking
Move the mmap semaphore locking out of set_guest_storage_key
and get_guest_storage_key. This makes the two functions more
like the other ptep_xxx operations and allows to avoid repeated
semaphore operations if multiple keys are read or written.
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Diffstat (limited to 'arch/s390/kvm/kvm-s390.c')
| -rw-r--r-- | arch/s390/kvm/kvm-s390.c | 26 |
1 files changed, 16 insertions, 10 deletions
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index 9d0e4d0487f4..d0156d7969e0 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -1050,26 +1050,30 @@ static long kvm_s390_get_skeys(struct kvm *kvm, struct kvm_s390_skeys *args) if (!keys) return -ENOMEM; + down_read(¤t->mm->mmap_sem); for (i = 0; i < args->count; i++) { hva = gfn_to_hva(kvm, args->start_gfn + i); if (kvm_is_error_hva(hva)) { r = -EFAULT; - goto out; + break; } curkey = get_guest_storage_key(current->mm, hva); if (IS_ERR_VALUE(curkey)) { r = curkey; - goto out; + break; } keys[i] = curkey; } + up_read(¤t->mm->mmap_sem); + + if (!r) { + r = copy_to_user((uint8_t __user *)args->skeydata_addr, keys, + sizeof(uint8_t) * args->count); + if (r) + r = -EFAULT; + } - r = copy_to_user((uint8_t __user *)args->skeydata_addr, keys, - sizeof(uint8_t) * args->count); - if (r) - r = -EFAULT; -out: kvfree(keys); return r; } @@ -1106,24 +1110,26 @@ static long kvm_s390_set_skeys(struct kvm *kvm, struct kvm_s390_skeys *args) if (r) goto out; + down_read(¤t->mm->mmap_sem); for (i = 0; i < args->count; i++) { hva = gfn_to_hva(kvm, args->start_gfn + i); if (kvm_is_error_hva(hva)) { r = -EFAULT; - goto out; + break; } /* Lowest order bit is reserved */ if (keys[i] & 0x01) { r = -EINVAL; - goto out; + break; } r = set_guest_storage_key(current->mm, hva, (unsigned long)keys[i], 0); if (r) - goto out; + break; } + up_read(¤t->mm->mmap_sem); out: kvfree(keys); return r; |