From: Janosch Frank <frankja@linux.vnet.ibm.com>
To: kvm@vger.kernel.org
Cc: schwidefsky@de.ibm.com, borntraeger@de.ibm.com, david@redhat.com,
dominik.dingel@gmail.com, linux-s390@vger.kernel.org
Subject: [RFC/PATCH 22/22] RFC: s390/mm: Add gmap lock classes
Date: Mon, 6 Nov 2017 23:30:00 +0100 [thread overview]
Message-ID: <1510007400-42493-23-git-send-email-frankja@linux.vnet.ibm.com> (raw)
In-Reply-To: <1510007400-42493-1-git-send-email-frankja@linux.vnet.ibm.com>
A shadow gmap and its parent are locked right after each other when
doing VSIE management. Lockdep can't differentiate between the two
classes without some help.
TODO: Not sure yet if I have to annotate all and if gmap_pmd_walk will
be used by both shadow and parent
Signed-off-by: Janosch Frank <frankja@linux.vnet.ibm.com>
---
arch/s390/include/asm/gmap.h | 6 ++++++
arch/s390/mm/gmap.c | 40 ++++++++++++++++++++--------------------
2 files changed, 26 insertions(+), 20 deletions(-)
diff --git a/arch/s390/include/asm/gmap.h b/arch/s390/include/asm/gmap.h
index 15a7834..31fad98 100644
--- a/arch/s390/include/asm/gmap.h
+++ b/arch/s390/include/asm/gmap.h
@@ -19,6 +19,12 @@
#define _SEGMENT_ENTRY_GMAP_UC 0x4000 /* user dirty (migration) */
#define _SEGMENT_ENTRY_GMAP_VSIE 0x8000 /* vsie bit */
+
+enum gmap_lock_class {
+ GMAP_LOCK_PARENT,
+ GMAP_LOCK_SHADOW
+};
+
/**
* struct gmap_struct - guest address space
* @list: list head for the mm->context gmap list
diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c
index 3cc2765..b17f424 100644
--- a/arch/s390/mm/gmap.c
+++ b/arch/s390/mm/gmap.c
@@ -198,7 +198,7 @@ static void gmap_free(struct gmap *gmap)
gmap_radix_tree_free(&gmap->host_to_guest);
/* Free split pmd page tables */
- spin_lock(&gmap->guest_table_lock);
+ spin_lock_nested(&gmap->guest_table_lock, GMAP_LOCK_PARENT);
list_for_each_entry_safe(page, next, &gmap->split_list, lru)
page_table_free_pgste(page);
spin_unlock(&gmap->guest_table_lock);
@@ -1385,7 +1385,7 @@ static int gmap_protect_rmap_large(struct gmap *sg, struct gmap_rmap *rmap,
if (pmd_val(*pmdp) & _SEGMENT_ENTRY_INVALID)
return -EAGAIN;
- spin_lock(&sg->guest_table_lock);
+ spin_lock_nested(&sg->guest_table_lock, GMAP_LOCK_SHADOW);
rc = gmap_protect_large(sg->parent, paddr, vmaddr, pmdp, hpmdp,
prot, GMAP_ENTRY_VSIE);
if (!rc)
@@ -1413,7 +1413,7 @@ static int gmap_protect_rmap_pte(struct gmap *sg, struct gmap_rmap *rmap,
ptep = pte_alloc_map_lock(sg->parent->mm, pmdp, paddr, &ptl);
if (ptep) {
- spin_lock(&sg->guest_table_lock);
+ spin_lock_nested(&sg->guest_table_lock, GMAP_LOCK_SHADOW);
rc = ptep_force_prot(sg->parent->mm, paddr, ptep, prot,
PGSTE_VSIE_BIT);
if (!rc)
@@ -1932,7 +1932,7 @@ struct gmap *gmap_shadow(struct gmap *parent, unsigned long asce,
/* only allow one real-space gmap shadow */
list_for_each_entry(sg, &parent->children, list) {
if (sg->orig_asce & _ASCE_REAL_SPACE) {
- spin_lock(&sg->guest_table_lock);
+ spin_lock_nested(&sg->guest_table_lock, GMAP_LOCK_SHADOW);
gmap_unshadow(sg);
spin_unlock(&sg->guest_table_lock);
list_del(&sg->list);
@@ -2004,7 +2004,7 @@ int gmap_shadow_r2t(struct gmap *sg, unsigned long saddr, unsigned long r2t,
page->index |= GMAP_SHADOW_FAKE_TABLE;
s_r2t = (unsigned long *) page_to_phys(page);
/* Install shadow region second table */
- spin_lock(&sg->guest_table_lock);
+ spin_lock_nested(&sg->guest_table_lock, GMAP_LOCK_SHADOW);
table = gmap_table_walk(sg, saddr, 4); /* get region-1 pointer */
if (!table) {
rc = -EAGAIN; /* Race with unshadow */
@@ -2037,7 +2037,7 @@ int gmap_shadow_r2t(struct gmap *sg, unsigned long saddr, unsigned long r2t,
offset = ((r2t & _REGION_ENTRY_OFFSET) >> 6) * PAGE_SIZE;
len = ((r2t & _REGION_ENTRY_LENGTH) + 1) * PAGE_SIZE - offset;
rc = gmap_protect_rmap(sg, raddr, origin + offset, len, PROT_READ);
- spin_lock(&sg->guest_table_lock);
+ spin_lock_nested(&sg->guest_table_lock, GMAP_LOCK_SHADOW);
if (!rc) {
table = gmap_table_walk(sg, saddr, 4);
if (!table || (*table & _REGION_ENTRY_ORIGIN) !=
@@ -2088,7 +2088,7 @@ int gmap_shadow_r3t(struct gmap *sg, unsigned long saddr, unsigned long r3t,
page->index |= GMAP_SHADOW_FAKE_TABLE;
s_r3t = (unsigned long *) page_to_phys(page);
/* Install shadow region second table */
- spin_lock(&sg->guest_table_lock);
+ spin_lock_nested(&sg->guest_table_lock, GMAP_LOCK_SHADOW);
table = gmap_table_walk(sg, saddr, 3); /* get region-2 pointer */
if (!table) {
rc = -EAGAIN; /* Race with unshadow */
@@ -2120,7 +2120,7 @@ int gmap_shadow_r3t(struct gmap *sg, unsigned long saddr, unsigned long r3t,
offset = ((r3t & _REGION_ENTRY_OFFSET) >> 6) * PAGE_SIZE;
len = ((r3t & _REGION_ENTRY_LENGTH) + 1) * PAGE_SIZE - offset;
rc = gmap_protect_rmap(sg, raddr, origin + offset, len, PROT_READ);
- spin_lock(&sg->guest_table_lock);
+ spin_lock_nested(&sg->guest_table_lock, GMAP_LOCK_SHADOW);
if (!rc) {
table = gmap_table_walk(sg, saddr, 3);
if (!table || (*table & _REGION_ENTRY_ORIGIN) !=
@@ -2171,7 +2171,7 @@ int gmap_shadow_sgt(struct gmap *sg, unsigned long saddr, unsigned long sgt,
page->index |= GMAP_SHADOW_FAKE_TABLE;
s_sgt = (unsigned long *) page_to_phys(page);
/* Install shadow region second table */
- spin_lock(&sg->guest_table_lock);
+ spin_lock_nested(&sg->guest_table_lock, GMAP_LOCK_SHADOW);
table = gmap_table_walk(sg, saddr, 2); /* get region-3 pointer */
if (!table) {
rc = -EAGAIN; /* Race with unshadow */
@@ -2204,7 +2204,7 @@ int gmap_shadow_sgt(struct gmap *sg, unsigned long saddr, unsigned long sgt,
offset = ((sgt & _REGION_ENTRY_OFFSET) >> 6) * PAGE_SIZE;
len = ((sgt & _REGION_ENTRY_LENGTH) + 1) * PAGE_SIZE - offset;
rc = gmap_protect_rmap(sg, raddr, origin + offset, len, PROT_READ);
- spin_lock(&sg->guest_table_lock);
+ spin_lock_nested(&sg->guest_table_lock, GMAP_LOCK_SHADOW);
if (!rc) {
table = gmap_table_walk(sg, saddr, 2);
if (!table || (*table & _REGION_ENTRY_ORIGIN) !=
@@ -2260,7 +2260,7 @@ int gmap_shadow_sgt_lookup(struct gmap *sg, unsigned long saddr,
int rc = -EAGAIN;
BUG_ON(!gmap_is_shadow(sg));
- spin_lock(&sg->guest_table_lock);
+ spin_lock_nested(&sg->guest_table_lock, GMAP_LOCK_SHADOW);
if (sg->asce & _ASCE_TYPE_MASK) {
/* >2 GB guest */
r3e = (unsigned long *) gmap_table_walk(sg, saddr, 2);
@@ -2327,7 +2327,7 @@ int gmap_shadow_pgt(struct gmap *sg, unsigned long saddr, unsigned long pgt,
page->index |= GMAP_SHADOW_FAKE_TABLE;
s_pgt = (unsigned long *) page_to_phys(page);
/* Install shadow page table */
- spin_lock(&sg->guest_table_lock);
+ spin_lock_nested(&sg->guest_table_lock, GMAP_LOCK_SHADOW);
table = gmap_table_walk(sg, saddr, 1); /* get segment pointer */
if (!table) {
rc = -EAGAIN; /* Race with unshadow */
@@ -2355,7 +2355,7 @@ int gmap_shadow_pgt(struct gmap *sg, unsigned long saddr, unsigned long pgt,
raddr = (saddr & _SEGMENT_MASK) | _SHADOW_RMAP_SEGMENT;
origin = pgt & _SEGMENT_ENTRY_ORIGIN & PAGE_MASK;
rc = gmap_protect_rmap(sg, raddr, origin, PAGE_SIZE, PROT_READ);
- spin_lock(&sg->guest_table_lock);
+ spin_lock_nested(&sg->guest_table_lock, GMAP_LOCK_SHADOW);
if (!rc) {
table = gmap_table_walk(sg, saddr, 1);
if (!table || (*table & _SEGMENT_ENTRY_ORIGIN) !=
@@ -2417,7 +2417,7 @@ int gmap_shadow_segment(struct gmap *sg, unsigned long saddr, pmd_t pmd)
if (spmdp) {
if (!pmd_large(*spmdp))
BUG();
- spin_lock(&sg->guest_table_lock);
+ spin_lock_nested(&sg->guest_table_lock, GMAP_LOCK_SHADOW);
/* Get shadow segment table pointer */
tpmdp = (pmd_t *) gmap_table_walk(sg, saddr, 1);
if (!tpmdp) {
@@ -2513,7 +2513,7 @@ int gmap_shadow_page(struct gmap *sg, unsigned long saddr, pte_t pte)
rc = -EAGAIN;
spmdp = gmap_pmd_op_walk(parent, paddr);
if (spmdp && !(pmd_val(*spmdp) & _SEGMENT_ENTRY_INVALID)) {
- spin_lock(&sg->guest_table_lock);
+ spin_lock_nested(&sg->guest_table_lock, GMAP_LOCK_SHADOW);
/* Get page table pointer */
tptep = (pte_t *) gmap_table_walk(sg, saddr, 0);
if (!tptep) {
@@ -2597,7 +2597,7 @@ static void gmap_shadow_notify_pmd(struct gmap *sg, unsigned long vmaddr,
BUG_ON(!gmap_is_shadow(sg));
- spin_lock(&sg->guest_table_lock);
+ spin_lock_nested(&sg->guest_table_lock, GMAP_LOCK_SHADOW);
if (sg->removed) {
spin_unlock(&sg->guest_table_lock);
return;
@@ -2658,7 +2658,7 @@ static void gmap_shadow_notify(struct gmap *sg, unsigned long vmaddr,
BUG_ON(!gmap_is_shadow(sg));
- spin_lock(&sg->guest_table_lock);
+ spin_lock_nested(&sg->guest_table_lock, GMAP_LOCK_SHADOW);
if (sg->removed) {
spin_unlock(&sg->guest_table_lock);
return;
@@ -2899,7 +2899,7 @@ static void gmap_pmdp_clear(struct mm_struct *mm, unsigned long vmaddr,
rcu_read_lock();
list_for_each_entry_rcu(gmap, &mm->context.gmap_list, list) {
- spin_lock(&gmap->guest_table_lock);
+ spin_lock_nested(&gmap->guest_table_lock, GMAP_LOCK_PARENT);
pmdp = (pmd_t *)radix_tree_delete(&gmap->host_to_guest,
vmaddr >> PMD_SHIFT);
if (pmdp) {
@@ -2949,7 +2949,7 @@ void gmap_pmdp_idte_local(struct mm_struct *mm, unsigned long vmaddr)
rcu_read_lock();
list_for_each_entry_rcu(gmap, &mm->context.gmap_list, list) {
- spin_lock(&gmap->guest_table_lock);
+ spin_lock_nested(&gmap->guest_table_lock, GMAP_LOCK_PARENT);
entry = radix_tree_delete(&gmap->host_to_guest,
vmaddr >> PMD_SHIFT);
if (entry) {
@@ -2984,7 +2984,7 @@ void gmap_pmdp_idte_global(struct mm_struct *mm, unsigned long vmaddr)
rcu_read_lock();
list_for_each_entry_rcu(gmap, &mm->context.gmap_list, list) {
- spin_lock(&gmap->guest_table_lock);
+ spin_lock_nested(&gmap->guest_table_lock, GMAP_LOCK_PARENT);
entry = radix_tree_delete(&gmap->host_to_guest,
vmaddr >> PMD_SHIFT);
if (entry) {
--
2.7.4
next prev parent reply other threads:[~2017-11-06 22:30 UTC|newest]
Thread overview: 42+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-11-06 22:29 [RFC/PATCH 00/22] KVM/s390: Hugetlbfs enablement Janosch Frank
2017-11-06 22:29 ` [RFC/PATCH 01/22] s390/mm: make gmap_protect_range more modular Janosch Frank
2017-11-08 10:40 ` David Hildenbrand
2017-11-08 12:21 ` Janosch Frank
2017-11-08 12:26 ` David Hildenbrand
2017-11-06 22:29 ` [RFC/PATCH 02/22] s390/mm: Abstract gmap notify bit setting Janosch Frank
2017-11-10 12:57 ` David Hildenbrand
2017-11-13 15:57 ` Janosch Frank
2017-11-15 9:30 ` David Hildenbrand
2017-11-06 22:29 ` [RFC/PATCH 03/22] s390/mm: add gmap PMD invalidation notification Janosch Frank
2017-11-15 9:55 ` David Hildenbrand
2017-11-17 9:02 ` Janosch Frank
2017-11-17 9:19 ` Martin Schwidefsky
2017-11-06 22:29 ` [RFC/PATCH 04/22] s390/mm: Add gmap pmd invalidation and clearing Janosch Frank
2017-11-06 22:29 ` [RFC/PATCH 05/22] s390/mm: hugetlb pages within a gmap can not be freed Janosch Frank
2017-11-06 22:29 ` [RFC/PATCH 06/22] s390/mm: Introduce gmap_pmdp_xchg Janosch Frank
2017-11-06 22:29 ` [RFC/PATCH 07/22] RFC: s390/mm: Transfer guest pmd protection to host Janosch Frank
2017-11-06 22:29 ` [RFC/PATCH 08/22] s390/mm: Add huge page dirty sync support Janosch Frank
2017-11-06 22:29 ` [RFC/PATCH 09/22] s390/mm: clear huge page storage keys on enable_skey Janosch Frank
2017-11-06 22:29 ` [RFC/PATCH 10/22] s390/mm: Add huge pmd storage key handling Janosch Frank
2017-11-06 22:29 ` [RFC/PATCH 11/22] s390/mm: Remove superfluous parameter Janosch Frank
2017-11-06 22:29 ` [RFC/PATCH 12/22] s390/mm: Add gmap_protect_large read protection support Janosch Frank
2017-11-06 22:29 ` [RFC/PATCH 13/22] s390/mm: Make gmap_read_table EDAT1 compatible Janosch Frank
2017-11-06 22:29 ` [RFC/PATCH 14/22] s390/mm: Make protect_rmap " Janosch Frank
2017-11-06 22:29 ` [RFC/PATCH 15/22] s390/mm: GMAP read table extensions Janosch Frank
2017-11-06 22:29 ` [RFC/PATCH 16/22] s390/mm: Add shadow segment code Janosch Frank
2017-11-06 22:29 ` [RFC/PATCH 17/22] s390/mm: Add VSIE reverse fake case Janosch Frank
2017-11-06 22:29 ` [RFC/PATCH 18/22] s390/mm: Remove gmap_pte_op_walk Janosch Frank
2017-11-06 22:29 ` [RFC/PATCH 19/22] s390/mm: Split huge pages if granular protection is needed Janosch Frank
2017-12-07 16:32 ` David Hildenbrand
2017-12-08 7:00 ` Janosch Frank
2017-11-06 22:29 ` [RFC/PATCH 20/22] s390/mm: Enable gmap huge pmd support Janosch Frank
2017-11-15 10:08 ` David Hildenbrand
2017-11-15 12:24 ` Janosch Frank
2017-11-06 22:29 ` [RFC/PATCH 21/22] KVM: s390: Add KVM HPAGE capability Janosch Frank
2017-11-07 10:07 ` Cornelia Huck
2017-11-07 10:53 ` Janosch Frank
2017-11-15 10:06 ` David Hildenbrand
2017-11-15 12:02 ` Janosch Frank
2017-11-06 22:30 ` Janosch Frank [this message]
2017-11-15 10:10 ` [RFC/PATCH 22/22] RFC: s390/mm: Add gmap lock classes David Hildenbrand
2017-11-15 12:16 ` Janosch Frank
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1510007400-42493-23-git-send-email-frankja@linux.vnet.ibm.com \
--to=frankja@linux.vnet.ibm.com \
--cc=borntraeger@de.ibm.com \
--cc=david@redhat.com \
--cc=dominik.dingel@gmail.com \
--cc=kvm@vger.kernel.org \
--cc=linux-s390@vger.kernel.org \
--cc=schwidefsky@de.ibm.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox