[PATCH 2/6] KVM: PPC: e500: Less function calls in kvm_vcpu_ioctl_config_tlb() after error detection

SF Markus Elfring
2016-08-28T17:14:07Z

Date: Sun, 28 Aug 2016 17:34:46 +0200

The kfree() function was called in two cases by the
kvm_vcpu_ioctl_config_tlb() function during error handling
even if the passed data structure element contained a null pointer.

* Split a condition check for memory allocation failures.

* Adjust jump targets according to the Linux coding style convention.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
---
arch/powerpc/kvm/e500_mmu.c | 30 ++++++++++++++++--------------
1 file changed, 16 insertions(+), 14 deletions(-)

diff --git a/arch/powerpc/kvm/e500_mmu.c b/arch/powerpc/kvm/e500_mmu.c
index 26f3737..b65a894 100644
--- a/arch/powerpc/kvm/e500_mmu.c
+++ b/arch/powerpc/kvm/e500_mmu.c
@@ -785,35 +785,39 @@ int kvm_vcpu_ioctl_config_tlb(struct kvm_vcpu *vcpu,

ret = get_user_pages_fast(cfg->array, num_pages, 1, pages);
if (ret < 0)
- goto err_pages;
+ goto free_pages;

if (ret != num_pages) {
num_pages = ret;
ret = -EFAULT;
- goto err_put_page;
+ goto put_pages;
}

virt = vmap(pages, num_pages, VM_MAP, PAGE_KERNEL);
if (!virt) {
ret = -ENOMEM;
- goto err_put_page;
+ goto put_pages;
}

privs[0] = kzalloc(sizeof(struct tlbe_priv) * params.tlb_sizes[0],
GFP_KERNEL);
+ if (!privs[0]) {
+ ret = -ENOMEM;
+ goto put_pages;
+ }
+
privs[1] = kzalloc(sizeof(struct tlbe_priv) * params.tlb_sizes[1],
GFP_KERNEL);
-
- if (!privs[0] || !privs[1]) {
+ if (!privs[1]) {
ret = -ENOMEM;
- goto err_privs;
+ goto free_privs_first;
}

g2h_bitmap = kzalloc(sizeof(u64) * params.tlb_sizes[1],
GFP_KERNEL);
if (!g2h_bitmap) {
ret = -ENOMEM;
- goto err_privs;
+ goto free_privs_second;
}

free_gtlb(vcpu_e500);
@@ -845,16 +849,14 @@ int kvm_vcpu_ioctl_config_tlb(struct kvm_vcpu *vcpu,

kvmppc_recalc_tlb1map_range(vcpu_e500);
return 0;
-
-err_privs:
- kfree(privs[0]);
+ free_privs_second:
kfree(privs[1]);
-
-err_put_page:
+ free_privs_first:
+ kfree(privs[0]);
+ put_pages:
for (i = 0; i < num_pages; i++)
put_page(pages[i]);
-
-err_pages:
+ free_pages:
kfree(pages);
return ret;
}
--
2.9.3