[PATCH 0/3] Replace current->mm by kvm->mm on powerpc/kvm

linuxppc-dev.lists.ozlabs.org archive mirror
 help / color / mirror / Atom feed

* [PATCH 0/3] Replace current->mm by kvm->mm on powerpc/kvm
@ 2019-09-23 18:43 Leonardo Bras
  2019-09-23 18:43 ` [PATCH 1/3] powerpc/kvm/book3s: Replace current->mm by kvm->mm Leonardo Bras
                   ` (2 more replies)
  0 siblings, 3 replies; 4+ messages in thread
From: Leonardo Bras @ 2019-09-23 18:43 UTC (permalink / raw)
  To: linuxppc-dev, linux-kernel; +Cc: Leonardo Bras

By replacing, we would reduce the use of 'global' current on code,
relying more in the contents of kvm struct.

On code, I found that in kvm_create_vm() there is:
kvm->mm = current->mm;

And that on every kvm_*_ioctl we have tests like that:
if (kvm->mm != current->mm)
        return -EIO;

So this change would be safe.

I split the changes in 3 patches, so it would be easier to read
and reject separated parts. If decided that squashing is better,
I see no problem doing that.

Best regards,

Leonardo Bras (3):
  powerpc/kvm/book3s: Replace current->mm by kvm->mm
  powerpc/kvm/book3e: Replace current->mm by kvm->mm
  powerpc/kvm/e500: Replace current->mm by kvm->mm

 arch/powerpc/kvm/book3s_64_mmu_hv.c |  4 ++--
 arch/powerpc/kvm/book3s_64_vio.c    |  6 +++---
 arch/powerpc/kvm/book3s_hv.c        | 10 +++++-----
 arch/powerpc/kvm/booke.c            |  2 +-
 arch/powerpc/kvm/e500_mmu_host.c    |  6 +++---
 5 files changed, 14 insertions(+), 14 deletions(-)

-- 
2.20.1


^ permalink raw reply	[flat|nested] 4+ messages in thread

* [PATCH 1/3] powerpc/kvm/book3s: Replace current->mm by kvm->mm
  2019-09-23 18:43 [PATCH 0/3] Replace current->mm by kvm->mm on powerpc/kvm Leonardo Bras
@ 2019-09-23 18:43 ` Leonardo Bras
  2019-09-23 18:43 ` [PATCH 2/3] powerpc/kvm/book3e: " Leonardo Bras
  2019-09-23 18:43 ` [PATCH 3/3] powerpc/kvm/e500: " Leonardo Bras
  2 siblings, 0 replies; 4+ messages in thread
From: Leonardo Bras @ 2019-09-23 18:43 UTC (permalink / raw)
  To: linuxppc-dev, linux-kernel; +Cc: Leonardo Bras

Given that in kvm_create_vm() there is:
kvm->mm = current->mm;

And that on every kvm_*_ioctl we have:
if (kvm->mm != current->mm)
	return -EIO;

I see no reason to keep using current->mm instead of kvm->mm.

By doing so, we would reduce the use of 'global' variables on code, relying
more in the contents of kvm struct.

Signed-off-by: Leonardo Bras <leonardo@linux.ibm.com>
---
 arch/powerpc/kvm/book3s_64_mmu_hv.c |  4 ++--
 arch/powerpc/kvm/book3s_64_vio.c    |  6 +++---
 arch/powerpc/kvm/book3s_hv.c        | 10 +++++-----
 3 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/arch/powerpc/kvm/book3s_64_mmu_hv.c b/arch/powerpc/kvm/book3s_64_mmu_hv.c
index f2b9aea43216..2f23cbc6c23e 100644
--- a/arch/powerpc/kvm/book3s_64_mmu_hv.c
+++ b/arch/powerpc/kvm/book3s_64_mmu_hv.c
@@ -296,7 +296,7 @@ static long kvmppc_virtmode_do_h_enter(struct kvm *kvm, unsigned long flags,
 	/* Protect linux PTE lookup from page table destruction */
 	rcu_read_lock_sched();	/* this disables preemption too */
 	ret = kvmppc_do_h_enter(kvm, flags, pte_index, pteh, ptel,
-				current->mm->pgd, false, pte_idx_ret);
+				kvm->mm->pgd, false, pte_idx_ret);
 	rcu_read_unlock_sched();
 	if (ret == H_TOO_HARD) {
 		/* this can't happen */
@@ -585,7 +585,7 @@ int kvmppc_book3s_hv_page_fault(struct kvm_run *run, struct kvm_vcpu *vcpu,
 	is_ci = false;
 	pfn = 0;
 	page = NULL;
-	mm = current->mm;
+	mm = kvm->mm;
 	pte_size = PAGE_SIZE;
 	writing = (dsisr & DSISR_ISSTORE) != 0;
 	/* If writing != 0, then the HPTE must allow writing, if we get here */
diff --git a/arch/powerpc/kvm/book3s_64_vio.c b/arch/powerpc/kvm/book3s_64_vio.c
index c4b606fe73eb..8069b35f2905 100644
--- a/arch/powerpc/kvm/book3s_64_vio.c
+++ b/arch/powerpc/kvm/book3s_64_vio.c
@@ -255,7 +255,7 @@ static int kvm_spapr_tce_release(struct inode *inode, struct file *filp)
 
 	kvm_put_kvm(stt->kvm);
 
-	account_locked_vm(current->mm,
+	account_locked_vm(kvm->mm,
 		kvmppc_stt_pages(kvmppc_tce_pages(stt->size)), false);
 	call_rcu(&stt->rcu, release_spapr_tce_table);
 
@@ -280,7 +280,7 @@ long kvm_vm_ioctl_create_spapr_tce(struct kvm *kvm,
 		return -EINVAL;
 
 	npages = kvmppc_tce_pages(size);
-	ret = account_locked_vm(current->mm, kvmppc_stt_pages(npages), true);
+	ret = account_locked_vm(kvm->mm, kvmppc_stt_pages(npages), true);
 	if (ret)
 		return ret;
 
@@ -326,7 +326,7 @@ long kvm_vm_ioctl_create_spapr_tce(struct kvm *kvm,
 
 	kfree(stt);
  fail_acct:
-	account_locked_vm(current->mm, kvmppc_stt_pages(npages), false);
+	account_locked_vm(kvm->mm, kvmppc_stt_pages(npages), false);
 	return ret;
 }
 
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index cde3f5a4b3e4..c5b6081b6de0 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -4265,7 +4265,7 @@ static int kvmppc_vcpu_run_hv(struct kvm_run *run, struct kvm_vcpu *vcpu)
 	user_vrsave = mfspr(SPRN_VRSAVE);
 
 	vcpu->arch.wqp = &vcpu->arch.vcore->wq;
-	vcpu->arch.pgdir = current->mm->pgd;
+	vcpu->arch.pgdir = kvm->mm->pgd;
 	vcpu->arch.state = KVMPPC_VCPU_BUSY_IN_HOST;
 
 	do {
@@ -4597,14 +4597,14 @@ static int kvmppc_hv_setup_htab_rma(struct kvm_vcpu *vcpu)
 
 	/* Look up the VMA for the start of this memory slot */
 	hva = memslot->userspace_addr;
-	down_read(&current->mm->mmap_sem);
-	vma = find_vma(current->mm, hva);
+	down_read(&kvm->mm->mmap_sem);
+	vma = find_vma(kvm->mm, hva);
 	if (!vma || vma->vm_start > hva || (vma->vm_flags & VM_IO))
 		goto up_out;
 
 	psize = vma_kernel_pagesize(vma);
 
-	up_read(&current->mm->mmap_sem);
+	up_read(&kvm->mm->mmap_sem);
 
 	/* We can handle 4k, 64k or 16M pages in the VRMA */
 	if (psize >= 0x1000000)
@@ -4637,7 +4637,7 @@ static int kvmppc_hv_setup_htab_rma(struct kvm_vcpu *vcpu)
 	return err;
 
  up_out:
-	up_read(&current->mm->mmap_sem);
+	up_read(&kvm->mm->mmap_sem);
 	goto out_srcu;
 }
 
-- 
2.20.1


^ permalink raw reply related	[flat|nested] 4+ messages in thread

* [PATCH 2/3] powerpc/kvm/book3e: Replace current->mm by kvm->mm
  2019-09-23 18:43 [PATCH 0/3] Replace current->mm by kvm->mm on powerpc/kvm Leonardo Bras
  2019-09-23 18:43 ` [PATCH 1/3] powerpc/kvm/book3s: Replace current->mm by kvm->mm Leonardo Bras
@ 2019-09-23 18:43 ` Leonardo Bras
  2019-09-23 18:43 ` [PATCH 3/3] powerpc/kvm/e500: " Leonardo Bras
  2 siblings, 0 replies; 4+ messages in thread
From: Leonardo Bras @ 2019-09-23 18:43 UTC (permalink / raw)
  To: linuxppc-dev, linux-kernel; +Cc: Leonardo Bras

Given that in kvm_create_vm() there is:
kvm->mm = current->mm;

And that on every kvm_*_ioctl we have:
if (kvm->mm != current->mm)
	return -EIO;

I see no reason to keep using current->mm instead of kvm->mm.

By doing so, we would reduce the use of 'global' variables on code, relying
more in the contents of kvm struct.

Signed-off-by: Leonardo Bras <leonardo@linux.ibm.com>
---
 arch/powerpc/kvm/booke.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c
index be9a45874194..383108263af5 100644
--- a/arch/powerpc/kvm/booke.c
+++ b/arch/powerpc/kvm/booke.c
@@ -775,7 +775,7 @@ int kvmppc_vcpu_run(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu)
 	debug = current->thread.debug;
 	current->thread.debug = vcpu->arch.dbg_reg;
 
-	vcpu->arch.pgdir = current->mm->pgd;
+	vcpu->arch.pgdir = kvm->mm->pgd;
 	kvmppc_fix_ee_before_entry();
 
 	ret = __kvmppc_vcpu_run(kvm_run, vcpu);
-- 
2.20.1


^ permalink raw reply related	[flat|nested] 4+ messages in thread

* [PATCH 3/3] powerpc/kvm/e500: Replace current->mm by kvm->mm
  2019-09-23 18:43 [PATCH 0/3] Replace current->mm by kvm->mm on powerpc/kvm Leonardo Bras
  2019-09-23 18:43 ` [PATCH 1/3] powerpc/kvm/book3s: Replace current->mm by kvm->mm Leonardo Bras
  2019-09-23 18:43 ` [PATCH 2/3] powerpc/kvm/book3e: " Leonardo Bras
@ 2019-09-23 18:43 ` Leonardo Bras
  2 siblings, 0 replies; 4+ messages in thread
From: Leonardo Bras @ 2019-09-23 18:43 UTC (permalink / raw)
  To: linuxppc-dev, linux-kernel; +Cc: Leonardo Bras

Given that in kvm_create_vm() there is:
kvm->mm = current->mm;

And that on every kvm_*_ioctl we have:
if (kvm->mm != current->mm)
        return -EIO;

I see no reason to keep using current->mm instead of kvm->mm.

By doing so, we would reduce the use of 'global' variables on code, relying
more in the contents of kvm struct.

Signed-off-by: Leonardo Bras <leonardo@linux.ibm.com>
---
 arch/powerpc/kvm/e500_mmu_host.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/arch/powerpc/kvm/e500_mmu_host.c b/arch/powerpc/kvm/e500_mmu_host.c
index 321db0fdb9db..425d13806645 100644
--- a/arch/powerpc/kvm/e500_mmu_host.c
+++ b/arch/powerpc/kvm/e500_mmu_host.c
@@ -355,9 +355,9 @@ static inline int kvmppc_e500_shadow_map(struct kvmppc_vcpu_e500 *vcpu_e500,
 
 	if (tlbsel == 1) {
 		struct vm_area_struct *vma;
-		down_read(&current->mm->mmap_sem);
+		down_read(&kvm->mm->mmap_sem);
 
-		vma = find_vma(current->mm, hva);
+		vma = find_vma(kvm->mm, hva);
 		if (vma && hva >= vma->vm_start &&
 		    (vma->vm_flags & VM_PFNMAP)) {
 			/*
@@ -441,7 +441,7 @@ static inline int kvmppc_e500_shadow_map(struct kvmppc_vcpu_e500 *vcpu_e500,
 			tsize = max(BOOK3E_PAGESZ_4K, tsize & ~1);
 		}
 
-		up_read(&current->mm->mmap_sem);
+		up_read(&kvm->mm->mmap_sem);
 	}
 
 	if (likely(!pfnmap)) {
-- 
2.20.1


^ permalink raw reply related	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2019-09-23 18:52 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2019-09-23 18:43 [PATCH 0/3] Replace current->mm by kvm->mm on powerpc/kvm Leonardo Bras
2019-09-23 18:43 ` [PATCH 1/3] powerpc/kvm/book3s: Replace current->mm by kvm->mm Leonardo Bras
2019-09-23 18:43 ` [PATCH 2/3] powerpc/kvm/book3e: " Leonardo Bras
2019-09-23 18:43 ` [PATCH 3/3] powerpc/kvm/e500: " Leonardo Bras

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).