* [PATCH] hugetlb: remove unused hstate in hugetlb_fault_mutex_hash()
[not found] <20190927151033.aad57472652a0b3a6948df6e@linux-foundation.org>
@ 2019-10-05 0:33 ` Wei Yang
2019-10-05 5:42 ` kbuild test robot
` (2 more replies)
0 siblings, 3 replies; 4+ messages in thread
From: Wei Yang @ 2019-10-05 0:33 UTC (permalink / raw)
To: mike.kravetz, akpm, hughd, aarcange; +Cc: linux-mm, linux-kernel, Wei Yang
The first parameter hstate in function hugetlb_fault_mutex_hash() is not
used anymore.
This patch removes it.
Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
---
fs/hugetlbfs/inode.c | 4 ++--
include/linux/hugetlb.h | 4 ++--
mm/hugetlb.c | 12 ++++++------
mm/userfaultfd.c | 5 +----
4 files changed, 11 insertions(+), 14 deletions(-)
diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index a478df035651..715db1e34174 100644
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -440,7 +440,7 @@ static void remove_inode_hugepages(struct inode *inode, loff_t lstart,
u32 hash;
index = page->index;
- hash = hugetlb_fault_mutex_hash(h, mapping, index, 0);
+ hash = hugetlb_fault_mutex_hash(mapping, index, 0);
mutex_lock(&hugetlb_fault_mutex_table[hash]);
/*
@@ -644,7 +644,7 @@ static long hugetlbfs_fallocate(struct file *file, int mode, loff_t offset,
addr = index * hpage_size;
/* mutex taken here, fault path and hole punch */
- hash = hugetlb_fault_mutex_hash(h, mapping, index, addr);
+ hash = hugetlb_fault_mutex_hash(mapping, index, addr);
mutex_lock(&hugetlb_fault_mutex_table[hash]);
/* See if already present in mapping to avoid alloc/free */
diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index 53fc34f930d0..40e9e3fad1cf 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -105,8 +105,8 @@ void move_hugetlb_state(struct page *oldpage, struct page *newpage, int reason);
void free_huge_page(struct page *page);
void hugetlb_fix_reserve_counts(struct inode *inode);
extern struct mutex *hugetlb_fault_mutex_table;
-u32 hugetlb_fault_mutex_hash(struct hstate *h, struct address_space *mapping,
- pgoff_t idx, unsigned long address);
+u32 hugetlb_fault_mutex_hash(struct address_space *mapping, pgoff_t idx,
+ unsigned long address);
pte_t *huge_pmd_share(struct mm_struct *mm, unsigned long addr, pud_t *pud);
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index ef37c85423a5..e0f033baac9d 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -3916,7 +3916,7 @@ static vm_fault_t hugetlb_no_page(struct mm_struct *mm,
* handling userfault. Reacquire after handling
* fault to make calling code simpler.
*/
- hash = hugetlb_fault_mutex_hash(h, mapping, idx, haddr);
+ hash = hugetlb_fault_mutex_hash(mapping, idx, haddr);
mutex_unlock(&hugetlb_fault_mutex_table[hash]);
ret = handle_userfault(&vmf, VM_UFFD_MISSING);
mutex_lock(&hugetlb_fault_mutex_table[hash]);
@@ -4043,8 +4043,8 @@ static vm_fault_t hugetlb_no_page(struct mm_struct *mm,
}
#ifdef CONFIG_SMP
-u32 hugetlb_fault_mutex_hash(struct hstate *h, struct address_space *mapping,
- pgoff_t idx, unsigned long address)
+u32 hugetlb_fault_mutex_hash(struct address_space *mapping, pgoff_t idx,
+ unsigned long address)
{
unsigned long key[2];
u32 hash;
@@ -4061,8 +4061,8 @@ u32 hugetlb_fault_mutex_hash(struct hstate *h, struct address_space *mapping,
* For uniprocesor systems we always use a single mutex, so just
* return 0 and avoid the hashing overhead.
*/
-u32 hugetlb_fault_mutex_hash(struct hstate *h, struct address_space *mapping,
- pgoff_t idx, unsigned long address)
+u32 hugetlb_fault_mutex_hash(struct address_space *mapping, pgoff_t idx,
+ unsigned long address)
{
return 0;
}
@@ -4106,7 +4106,7 @@ vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,
* get spurious allocation failures if two CPUs race to instantiate
* the same page in the page cache.
*/
- hash = hugetlb_fault_mutex_hash(h, mapping, idx, haddr);
+ hash = hugetlb_fault_mutex_hash(mapping, idx, haddr);
mutex_lock(&hugetlb_fault_mutex_table[hash]);
entry = huge_ptep_get(ptep);
diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c
index 0a40746a5b1e..5c0a80626cf0 100644
--- a/mm/userfaultfd.c
+++ b/mm/userfaultfd.c
@@ -214,7 +214,6 @@ static __always_inline ssize_t __mcopy_atomic_hugetlb(struct mm_struct *dst_mm,
unsigned long src_addr, dst_addr;
long copied;
struct page *page;
- struct hstate *h;
unsigned long vma_hpagesize;
pgoff_t idx;
u32 hash;
@@ -271,8 +270,6 @@ static __always_inline ssize_t __mcopy_atomic_hugetlb(struct mm_struct *dst_mm,
goto out_unlock;
}
- h = hstate_vma(dst_vma);
-
while (src_addr < src_start + len) {
pte_t dst_pteval;
@@ -283,7 +280,7 @@ static __always_inline ssize_t __mcopy_atomic_hugetlb(struct mm_struct *dst_mm,
*/
idx = linear_page_index(dst_vma, dst_addr);
mapping = dst_vma->vm_file->f_mapping;
- hash = hugetlb_fault_mutex_hash(h, mapping, idx, dst_addr);
+ hash = hugetlb_fault_mutex_hash(mapping, idx, dst_addr);
mutex_lock(&hugetlb_fault_mutex_table[hash]);
err = -ENOMEM;
--
2.17.1
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH] hugetlb: remove unused hstate in hugetlb_fault_mutex_hash()
2019-10-05 0:33 ` [PATCH] hugetlb: remove unused hstate in hugetlb_fault_mutex_hash() Wei Yang
@ 2019-10-05 5:42 ` kbuild test robot
2019-10-05 5:43 ` kbuild test robot
2019-10-06 2:25 ` kbuild test robot
2 siblings, 0 replies; 4+ messages in thread
From: kbuild test robot @ 2019-10-05 5:42 UTC (permalink / raw)
To: Wei Yang
Cc: kbuild-all, mike.kravetz, akpm, hughd, aarcange, linux-mm,
linux-kernel, Wei Yang
[-- Attachment #1: Type: text/plain, Size: 6189 bytes --]
Hi Wei,
Thank you for the patch! Perhaps something to improve:
[auto build test WARNING on linus/master]
[cannot apply to v5.4-rc1 next-20191004]
[if your patch is applied to the wrong git tree, please drop us a note to help
improve the system. BTW, we also suggest to use '--base' option to specify the
base tree in git format-patch, please see https://stackoverflow.com/a/37406982]
url: https://github.com/0day-ci/linux/commits/Wei-Yang/hugetlb-remove-unused-hstate-in-hugetlb_fault_mutex_hash/20191005-090034
config: x86_64-fedora-25 (attached as .config)
compiler: gcc-7 (Debian 7.4.0-13) 7.4.0
reproduce:
# save the attached .config to linux build tree
make ARCH=x86_64
If you fix the issue, kindly add following tag
Reported-by: kbuild test robot <lkp@intel.com>
All warnings (new ones prefixed by >>):
In file included from include/asm-generic/bug.h:5:0,
from arch/x86/include/asm/bug.h:83,
from include/linux/bug.h:5,
from include/linux/mmdebug.h:5,
from include/linux/mm.h:9,
from mm/userfaultfd.c:8:
mm/userfaultfd.c: In function '__mcopy_atomic_hugetlb':
mm/userfaultfd.c:262:40: error: 'h' undeclared (first use in this function)
VM_BUG_ON(dst_addr & ~huge_page_mask(h));
^
include/linux/compiler.h:78:42: note: in definition of macro 'unlikely'
# define unlikely(x) __builtin_expect(!!(x), 0)
^
>> include/linux/mmdebug.h:18:25: note: in expansion of macro 'BUG_ON'
#define VM_BUG_ON(cond) BUG_ON(cond)
^~~~~~
mm/userfaultfd.c:262:3: note: in expansion of macro 'VM_BUG_ON'
VM_BUG_ON(dst_addr & ~huge_page_mask(h));
^~~~~~~~~
mm/userfaultfd.c:262:40: note: each undeclared identifier is reported only once for each function it appears in
VM_BUG_ON(dst_addr & ~huge_page_mask(h));
^
include/linux/compiler.h:78:42: note: in definition of macro 'unlikely'
# define unlikely(x) __builtin_expect(!!(x), 0)
^
>> include/linux/mmdebug.h:18:25: note: in expansion of macro 'BUG_ON'
#define VM_BUG_ON(cond) BUG_ON(cond)
^~~~~~
mm/userfaultfd.c:262:3: note: in expansion of macro 'VM_BUG_ON'
VM_BUG_ON(dst_addr & ~huge_page_mask(h));
^~~~~~~~~
vim +/BUG_ON +18 include/linux/mmdebug.h
309381feaee564 Sasha Levin 2014-01-23 16
59ea746337c69f Jiri Slaby 2008-06-12 17 #ifdef CONFIG_DEBUG_VM
59ea746337c69f Jiri Slaby 2008-06-12 @18 #define VM_BUG_ON(cond) BUG_ON(cond)
309381feaee564 Sasha Levin 2014-01-23 19 #define VM_BUG_ON_PAGE(cond, page) \
e4f674229ce63d Dave Hansen 2014-06-04 20 do { \
e4f674229ce63d Dave Hansen 2014-06-04 21 if (unlikely(cond)) { \
e4f674229ce63d Dave Hansen 2014-06-04 22 dump_page(page, "VM_BUG_ON_PAGE(" __stringify(cond)")");\
e4f674229ce63d Dave Hansen 2014-06-04 23 BUG(); \
e4f674229ce63d Dave Hansen 2014-06-04 24 } \
e4f674229ce63d Dave Hansen 2014-06-04 25 } while (0)
fa3759ccd5651c Sasha Levin 2014-10-09 26 #define VM_BUG_ON_VMA(cond, vma) \
fa3759ccd5651c Sasha Levin 2014-10-09 27 do { \
fa3759ccd5651c Sasha Levin 2014-10-09 28 if (unlikely(cond)) { \
fa3759ccd5651c Sasha Levin 2014-10-09 29 dump_vma(vma); \
fa3759ccd5651c Sasha Levin 2014-10-09 30 BUG(); \
fa3759ccd5651c Sasha Levin 2014-10-09 31 } \
fa3759ccd5651c Sasha Levin 2014-10-09 32 } while (0)
31c9afa6db122a Sasha Levin 2014-10-09 33 #define VM_BUG_ON_MM(cond, mm) \
31c9afa6db122a Sasha Levin 2014-10-09 34 do { \
31c9afa6db122a Sasha Levin 2014-10-09 35 if (unlikely(cond)) { \
31c9afa6db122a Sasha Levin 2014-10-09 36 dump_mm(mm); \
31c9afa6db122a Sasha Levin 2014-10-09 37 BUG(); \
31c9afa6db122a Sasha Levin 2014-10-09 38 } \
31c9afa6db122a Sasha Levin 2014-10-09 39 } while (0)
91241681c62a5a Michal Hocko 2018-04-05 40 #define VM_WARN_ON(cond) (void)WARN_ON(cond)
91241681c62a5a Michal Hocko 2018-04-05 41 #define VM_WARN_ON_ONCE(cond) (void)WARN_ON_ONCE(cond)
91241681c62a5a Michal Hocko 2018-04-05 42 #define VM_WARN_ONCE(cond, format...) (void)WARN_ONCE(cond, format)
91241681c62a5a Michal Hocko 2018-04-05 43 #define VM_WARN(cond, format...) (void)WARN(cond, format)
59ea746337c69f Jiri Slaby 2008-06-12 44 #else
02602a18c32d76 Konstantin Khlebnikov 2012-05-29 45 #define VM_BUG_ON(cond) BUILD_BUG_ON_INVALID(cond)
309381feaee564 Sasha Levin 2014-01-23 46 #define VM_BUG_ON_PAGE(cond, page) VM_BUG_ON(cond)
fa3759ccd5651c Sasha Levin 2014-10-09 47 #define VM_BUG_ON_VMA(cond, vma) VM_BUG_ON(cond)
31c9afa6db122a Sasha Levin 2014-10-09 48 #define VM_BUG_ON_MM(cond, mm) VM_BUG_ON(cond)
02a8efeda894d3 Andrew Morton 2014-06-04 49 #define VM_WARN_ON(cond) BUILD_BUG_ON_INVALID(cond)
02a8efeda894d3 Andrew Morton 2014-06-04 50 #define VM_WARN_ON_ONCE(cond) BUILD_BUG_ON_INVALID(cond)
ef6b571fb8920d Andrew Morton 2014-08-06 51 #define VM_WARN_ONCE(cond, format...) BUILD_BUG_ON_INVALID(cond)
a54f9aebaa9f0e Aneesh Kumar K.V 2016-07-26 52 #define VM_WARN(cond, format...) BUILD_BUG_ON_INVALID(cond)
59ea746337c69f Jiri Slaby 2008-06-12 53 #endif
59ea746337c69f Jiri Slaby 2008-06-12 54
:::::: The code at line 18 was first introduced by commit
:::::: 59ea746337c69f6a5f1bc4d5e8544b3cbf12f801 MM: virtual address debug
:::::: TO: Jiri Slaby <jirislaby@gmail.com>
:::::: CC: Ingo Molnar <mingo@elte.hu>
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 51184 bytes --]
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] hugetlb: remove unused hstate in hugetlb_fault_mutex_hash()
2019-10-05 0:33 ` [PATCH] hugetlb: remove unused hstate in hugetlb_fault_mutex_hash() Wei Yang
2019-10-05 5:42 ` kbuild test robot
@ 2019-10-05 5:43 ` kbuild test robot
2019-10-06 2:25 ` kbuild test robot
2 siblings, 0 replies; 4+ messages in thread
From: kbuild test robot @ 2019-10-05 5:43 UTC (permalink / raw)
To: Wei Yang
Cc: kbuild-all, mike.kravetz, akpm, hughd, aarcange, linux-mm,
linux-kernel, Wei Yang
[-- Attachment #1: Type: text/plain, Size: 20198 bytes --]
Hi Wei,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on linus/master]
[cannot apply to v5.4-rc1 next-20191004]
[if your patch is applied to the wrong git tree, please drop us a note to help
improve the system. BTW, we also suggest to use '--base' option to specify the
base tree in git format-patch, please see https://stackoverflow.com/a/37406982]
url: https://github.com/0day-ci/linux/commits/Wei-Yang/hugetlb-remove-unused-hstate-in-hugetlb_fault_mutex_hash/20191005-090034
config: x86_64-lkp (attached as .config)
compiler: gcc-7 (Debian 7.4.0-13) 7.4.0
reproduce:
# save the attached .config to linux build tree
make ARCH=x86_64
If you fix the issue, kindly add following tag
Reported-by: kbuild test robot <lkp@intel.com>
All error/warnings (new ones prefixed by >>):
In file included from include/linux/kernel.h:16:0,
from include/asm-generic/bug.h:19,
from arch/x86/include/asm/bug.h:83,
from include/linux/bug.h:5,
from include/linux/mmdebug.h:5,
from include/linux/mm.h:9,
from mm/userfaultfd.c:8:
mm/userfaultfd.c: In function '__mcopy_atomic_hugetlb':
>> mm/userfaultfd.c:262:40: error: 'h' undeclared (first use in this function)
VM_BUG_ON(dst_addr & ~huge_page_mask(h));
^
include/linux/build_bug.h:30:63: note: in definition of macro 'BUILD_BUG_ON_INVALID'
#define BUILD_BUG_ON_INVALID(e) ((void)(sizeof((__force long)(e))))
^
>> mm/userfaultfd.c:262:3: note: in expansion of macro 'VM_BUG_ON'
VM_BUG_ON(dst_addr & ~huge_page_mask(h));
^~~~~~~~~
mm/userfaultfd.c:262:40: note: each undeclared identifier is reported only once for each function it appears in
VM_BUG_ON(dst_addr & ~huge_page_mask(h));
^
include/linux/build_bug.h:30:63: note: in definition of macro 'BUILD_BUG_ON_INVALID'
#define BUILD_BUG_ON_INVALID(e) ((void)(sizeof((__force long)(e))))
^
>> mm/userfaultfd.c:262:3: note: in expansion of macro 'VM_BUG_ON'
VM_BUG_ON(dst_addr & ~huge_page_mask(h));
^~~~~~~~~
vim +/h +262 mm/userfaultfd.c
c1a4de99fada21 Andrea Arcangeli 2015-09-04 167
60d4d2d2b40e44 Mike Kravetz 2017-02-22 168 #ifdef CONFIG_HUGETLB_PAGE
60d4d2d2b40e44 Mike Kravetz 2017-02-22 169 /*
60d4d2d2b40e44 Mike Kravetz 2017-02-22 170 * __mcopy_atomic processing for HUGETLB vmas. Note that this routine is
60d4d2d2b40e44 Mike Kravetz 2017-02-22 171 * called with mmap_sem held, it will release mmap_sem before returning.
60d4d2d2b40e44 Mike Kravetz 2017-02-22 172 */
60d4d2d2b40e44 Mike Kravetz 2017-02-22 173 static __always_inline ssize_t __mcopy_atomic_hugetlb(struct mm_struct *dst_mm,
60d4d2d2b40e44 Mike Kravetz 2017-02-22 174 struct vm_area_struct *dst_vma,
60d4d2d2b40e44 Mike Kravetz 2017-02-22 175 unsigned long dst_start,
60d4d2d2b40e44 Mike Kravetz 2017-02-22 176 unsigned long src_start,
60d4d2d2b40e44 Mike Kravetz 2017-02-22 177 unsigned long len,
60d4d2d2b40e44 Mike Kravetz 2017-02-22 178 bool zeropage)
60d4d2d2b40e44 Mike Kravetz 2017-02-22 179 {
1c9e8def43a345 Mike Kravetz 2017-02-22 180 int vm_alloc_shared = dst_vma->vm_flags & VM_SHARED;
1c9e8def43a345 Mike Kravetz 2017-02-22 181 int vm_shared = dst_vma->vm_flags & VM_SHARED;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 182 ssize_t err;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 183 pte_t *dst_pte;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 184 unsigned long src_addr, dst_addr;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 185 long copied;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 186 struct page *page;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 187 unsigned long vma_hpagesize;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 188 pgoff_t idx;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 189 u32 hash;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 190 struct address_space *mapping;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 191
60d4d2d2b40e44 Mike Kravetz 2017-02-22 192 /*
60d4d2d2b40e44 Mike Kravetz 2017-02-22 193 * There is no default zero huge page for all huge page sizes as
60d4d2d2b40e44 Mike Kravetz 2017-02-22 194 * supported by hugetlb. A PMD_SIZE huge pages may exist as used
60d4d2d2b40e44 Mike Kravetz 2017-02-22 195 * by THP. Since we can not reliably insert a zero page, this
60d4d2d2b40e44 Mike Kravetz 2017-02-22 196 * feature is not supported.
60d4d2d2b40e44 Mike Kravetz 2017-02-22 197 */
60d4d2d2b40e44 Mike Kravetz 2017-02-22 198 if (zeropage) {
60d4d2d2b40e44 Mike Kravetz 2017-02-22 199 up_read(&dst_mm->mmap_sem);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 200 return -EINVAL;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 201 }
60d4d2d2b40e44 Mike Kravetz 2017-02-22 202
60d4d2d2b40e44 Mike Kravetz 2017-02-22 203 src_addr = src_start;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 204 dst_addr = dst_start;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 205 copied = 0;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 206 page = NULL;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 207 vma_hpagesize = vma_kernel_pagesize(dst_vma);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 208
60d4d2d2b40e44 Mike Kravetz 2017-02-22 209 /*
60d4d2d2b40e44 Mike Kravetz 2017-02-22 210 * Validate alignment based on huge page size
60d4d2d2b40e44 Mike Kravetz 2017-02-22 211 */
60d4d2d2b40e44 Mike Kravetz 2017-02-22 212 err = -EINVAL;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 213 if (dst_start & (vma_hpagesize - 1) || len & (vma_hpagesize - 1))
60d4d2d2b40e44 Mike Kravetz 2017-02-22 214 goto out_unlock;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 215
60d4d2d2b40e44 Mike Kravetz 2017-02-22 216 retry:
60d4d2d2b40e44 Mike Kravetz 2017-02-22 217 /*
60d4d2d2b40e44 Mike Kravetz 2017-02-22 218 * On routine entry dst_vma is set. If we had to drop mmap_sem and
60d4d2d2b40e44 Mike Kravetz 2017-02-22 219 * retry, dst_vma will be set to NULL and we must lookup again.
60d4d2d2b40e44 Mike Kravetz 2017-02-22 220 */
60d4d2d2b40e44 Mike Kravetz 2017-02-22 221 if (!dst_vma) {
27d02568f529e9 Mike Rapoport 2017-02-24 222 err = -ENOENT;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 223 dst_vma = find_vma(dst_mm, dst_start);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 224 if (!dst_vma || !is_vm_hugetlb_page(dst_vma))
60d4d2d2b40e44 Mike Kravetz 2017-02-22 225 goto out_unlock;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 226 /*
29ec90660d68bb Andrea Arcangeli 2018-11-30 227 * Check the vma is registered in uffd, this is
29ec90660d68bb Andrea Arcangeli 2018-11-30 228 * required to enforce the VM_MAYWRITE check done at
29ec90660d68bb Andrea Arcangeli 2018-11-30 229 * uffd registration time.
60d4d2d2b40e44 Mike Kravetz 2017-02-22 230 */
27d02568f529e9 Mike Rapoport 2017-02-24 231 if (!dst_vma->vm_userfaultfd_ctx.ctx)
27d02568f529e9 Mike Rapoport 2017-02-24 232 goto out_unlock;
27d02568f529e9 Mike Rapoport 2017-02-24 233
60d4d2d2b40e44 Mike Kravetz 2017-02-22 234 if (dst_start < dst_vma->vm_start ||
60d4d2d2b40e44 Mike Kravetz 2017-02-22 235 dst_start + len > dst_vma->vm_end)
60d4d2d2b40e44 Mike Kravetz 2017-02-22 236 goto out_unlock;
1c9e8def43a345 Mike Kravetz 2017-02-22 237
27d02568f529e9 Mike Rapoport 2017-02-24 238 err = -EINVAL;
27d02568f529e9 Mike Rapoport 2017-02-24 239 if (vma_hpagesize != vma_kernel_pagesize(dst_vma))
27d02568f529e9 Mike Rapoport 2017-02-24 240 goto out_unlock;
27d02568f529e9 Mike Rapoport 2017-02-24 241
1c9e8def43a345 Mike Kravetz 2017-02-22 242 vm_shared = dst_vma->vm_flags & VM_SHARED;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 243 }
60d4d2d2b40e44 Mike Kravetz 2017-02-22 244
60d4d2d2b40e44 Mike Kravetz 2017-02-22 245 if (WARN_ON(dst_addr & (vma_hpagesize - 1) ||
60d4d2d2b40e44 Mike Kravetz 2017-02-22 246 (len - copied) & (vma_hpagesize - 1)))
60d4d2d2b40e44 Mike Kravetz 2017-02-22 247 goto out_unlock;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 248
60d4d2d2b40e44 Mike Kravetz 2017-02-22 249 /*
1c9e8def43a345 Mike Kravetz 2017-02-22 250 * If not shared, ensure the dst_vma has a anon_vma.
60d4d2d2b40e44 Mike Kravetz 2017-02-22 251 */
60d4d2d2b40e44 Mike Kravetz 2017-02-22 252 err = -ENOMEM;
1c9e8def43a345 Mike Kravetz 2017-02-22 253 if (!vm_shared) {
60d4d2d2b40e44 Mike Kravetz 2017-02-22 254 if (unlikely(anon_vma_prepare(dst_vma)))
60d4d2d2b40e44 Mike Kravetz 2017-02-22 255 goto out_unlock;
1c9e8def43a345 Mike Kravetz 2017-02-22 256 }
60d4d2d2b40e44 Mike Kravetz 2017-02-22 257
60d4d2d2b40e44 Mike Kravetz 2017-02-22 258 while (src_addr < src_start + len) {
60d4d2d2b40e44 Mike Kravetz 2017-02-22 259 pte_t dst_pteval;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 260
60d4d2d2b40e44 Mike Kravetz 2017-02-22 261 BUG_ON(dst_addr >= dst_start + len);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 @262 VM_BUG_ON(dst_addr & ~huge_page_mask(h));
60d4d2d2b40e44 Mike Kravetz 2017-02-22 263
60d4d2d2b40e44 Mike Kravetz 2017-02-22 264 /*
ddeaab32a89f04 Mike Kravetz 2019-01-08 265 * Serialize via hugetlb_fault_mutex
60d4d2d2b40e44 Mike Kravetz 2017-02-22 266 */
b43a9990055958 Mike Kravetz 2018-12-28 267 idx = linear_page_index(dst_vma, dst_addr);
ddeaab32a89f04 Mike Kravetz 2019-01-08 268 mapping = dst_vma->vm_file->f_mapping;
2b52c262f0e75d Wei Yang 2019-10-05 269 hash = hugetlb_fault_mutex_hash(mapping, idx, dst_addr);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 270 mutex_lock(&hugetlb_fault_mutex_table[hash]);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 271
60d4d2d2b40e44 Mike Kravetz 2017-02-22 272 err = -ENOMEM;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 273 dst_pte = huge_pte_alloc(dst_mm, dst_addr, huge_page_size(h));
60d4d2d2b40e44 Mike Kravetz 2017-02-22 274 if (!dst_pte) {
60d4d2d2b40e44 Mike Kravetz 2017-02-22 275 mutex_unlock(&hugetlb_fault_mutex_table[hash]);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 276 goto out_unlock;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 277 }
60d4d2d2b40e44 Mike Kravetz 2017-02-22 278
60d4d2d2b40e44 Mike Kravetz 2017-02-22 279 err = -EEXIST;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 280 dst_pteval = huge_ptep_get(dst_pte);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 281 if (!huge_pte_none(dst_pteval)) {
60d4d2d2b40e44 Mike Kravetz 2017-02-22 282 mutex_unlock(&hugetlb_fault_mutex_table[hash]);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 283 goto out_unlock;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 284 }
60d4d2d2b40e44 Mike Kravetz 2017-02-22 285
60d4d2d2b40e44 Mike Kravetz 2017-02-22 286 err = hugetlb_mcopy_atomic_pte(dst_mm, dst_pte, dst_vma,
60d4d2d2b40e44 Mike Kravetz 2017-02-22 287 dst_addr, src_addr, &page);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 288
60d4d2d2b40e44 Mike Kravetz 2017-02-22 289 mutex_unlock(&hugetlb_fault_mutex_table[hash]);
1c9e8def43a345 Mike Kravetz 2017-02-22 290 vm_alloc_shared = vm_shared;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 291
60d4d2d2b40e44 Mike Kravetz 2017-02-22 292 cond_resched();
60d4d2d2b40e44 Mike Kravetz 2017-02-22 293
9e368259ad9883 Andrea Arcangeli 2018-11-30 294 if (unlikely(err == -ENOENT)) {
60d4d2d2b40e44 Mike Kravetz 2017-02-22 295 up_read(&dst_mm->mmap_sem);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 296 BUG_ON(!page);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 297
60d4d2d2b40e44 Mike Kravetz 2017-02-22 298 err = copy_huge_page_from_user(page,
60d4d2d2b40e44 Mike Kravetz 2017-02-22 299 (const void __user *)src_addr,
810a56b943e265 Mike Kravetz 2017-02-22 300 pages_per_huge_page(h), true);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 301 if (unlikely(err)) {
60d4d2d2b40e44 Mike Kravetz 2017-02-22 302 err = -EFAULT;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 303 goto out;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 304 }
60d4d2d2b40e44 Mike Kravetz 2017-02-22 305 down_read(&dst_mm->mmap_sem);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 306
60d4d2d2b40e44 Mike Kravetz 2017-02-22 307 dst_vma = NULL;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 308 goto retry;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 309 } else
60d4d2d2b40e44 Mike Kravetz 2017-02-22 310 BUG_ON(page);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 311
60d4d2d2b40e44 Mike Kravetz 2017-02-22 312 if (!err) {
60d4d2d2b40e44 Mike Kravetz 2017-02-22 313 dst_addr += vma_hpagesize;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 314 src_addr += vma_hpagesize;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 315 copied += vma_hpagesize;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 316
60d4d2d2b40e44 Mike Kravetz 2017-02-22 317 if (fatal_signal_pending(current))
60d4d2d2b40e44 Mike Kravetz 2017-02-22 318 err = -EINTR;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 319 }
60d4d2d2b40e44 Mike Kravetz 2017-02-22 320 if (err)
60d4d2d2b40e44 Mike Kravetz 2017-02-22 321 break;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 322 }
60d4d2d2b40e44 Mike Kravetz 2017-02-22 323
60d4d2d2b40e44 Mike Kravetz 2017-02-22 324 out_unlock:
60d4d2d2b40e44 Mike Kravetz 2017-02-22 325 up_read(&dst_mm->mmap_sem);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 326 out:
21205bf8f77b23 Mike Kravetz 2017-02-22 327 if (page) {
21205bf8f77b23 Mike Kravetz 2017-02-22 328 /*
21205bf8f77b23 Mike Kravetz 2017-02-22 329 * We encountered an error and are about to free a newly
1c9e8def43a345 Mike Kravetz 2017-02-22 330 * allocated huge page.
1c9e8def43a345 Mike Kravetz 2017-02-22 331 *
1c9e8def43a345 Mike Kravetz 2017-02-22 332 * Reservation handling is very subtle, and is different for
1c9e8def43a345 Mike Kravetz 2017-02-22 333 * private and shared mappings. See the routine
1c9e8def43a345 Mike Kravetz 2017-02-22 334 * restore_reserve_on_error for details. Unfortunately, we
1c9e8def43a345 Mike Kravetz 2017-02-22 335 * can not call restore_reserve_on_error now as it would
1c9e8def43a345 Mike Kravetz 2017-02-22 336 * require holding mmap_sem.
1c9e8def43a345 Mike Kravetz 2017-02-22 337 *
1c9e8def43a345 Mike Kravetz 2017-02-22 338 * If a reservation for the page existed in the reservation
1c9e8def43a345 Mike Kravetz 2017-02-22 339 * map of a private mapping, the map was modified to indicate
1c9e8def43a345 Mike Kravetz 2017-02-22 340 * the reservation was consumed when the page was allocated.
1c9e8def43a345 Mike Kravetz 2017-02-22 341 * We clear the PagePrivate flag now so that the global
21205bf8f77b23 Mike Kravetz 2017-02-22 342 * reserve count will not be incremented in free_huge_page.
21205bf8f77b23 Mike Kravetz 2017-02-22 343 * The reservation map will still indicate the reservation
21205bf8f77b23 Mike Kravetz 2017-02-22 344 * was consumed and possibly prevent later page allocation.
1c9e8def43a345 Mike Kravetz 2017-02-22 345 * This is better than leaking a global reservation. If no
1c9e8def43a345 Mike Kravetz 2017-02-22 346 * reservation existed, it is still safe to clear PagePrivate
1c9e8def43a345 Mike Kravetz 2017-02-22 347 * as no adjustments to reservation counts were made during
1c9e8def43a345 Mike Kravetz 2017-02-22 348 * allocation.
1c9e8def43a345 Mike Kravetz 2017-02-22 349 *
1c9e8def43a345 Mike Kravetz 2017-02-22 350 * The reservation map for shared mappings indicates which
1c9e8def43a345 Mike Kravetz 2017-02-22 351 * pages have reservations. When a huge page is allocated
1c9e8def43a345 Mike Kravetz 2017-02-22 352 * for an address with a reservation, no change is made to
1c9e8def43a345 Mike Kravetz 2017-02-22 353 * the reserve map. In this case PagePrivate will be set
1c9e8def43a345 Mike Kravetz 2017-02-22 354 * to indicate that the global reservation count should be
1c9e8def43a345 Mike Kravetz 2017-02-22 355 * incremented when the page is freed. This is the desired
1c9e8def43a345 Mike Kravetz 2017-02-22 356 * behavior. However, when a huge page is allocated for an
1c9e8def43a345 Mike Kravetz 2017-02-22 357 * address without a reservation a reservation entry is added
1c9e8def43a345 Mike Kravetz 2017-02-22 358 * to the reservation map, and PagePrivate will not be set.
1c9e8def43a345 Mike Kravetz 2017-02-22 359 * When the page is freed, the global reserve count will NOT
1c9e8def43a345 Mike Kravetz 2017-02-22 360 * be incremented and it will appear as though we have leaked
1c9e8def43a345 Mike Kravetz 2017-02-22 361 * reserved page. In this case, set PagePrivate so that the
1c9e8def43a345 Mike Kravetz 2017-02-22 362 * global reserve count will be incremented to match the
1c9e8def43a345 Mike Kravetz 2017-02-22 363 * reservation map entry which was created.
1c9e8def43a345 Mike Kravetz 2017-02-22 364 *
1c9e8def43a345 Mike Kravetz 2017-02-22 365 * Note that vm_alloc_shared is based on the flags of the vma
1c9e8def43a345 Mike Kravetz 2017-02-22 366 * for which the page was originally allocated. dst_vma could
1c9e8def43a345 Mike Kravetz 2017-02-22 367 * be different or NULL on error.
21205bf8f77b23 Mike Kravetz 2017-02-22 368 */
1c9e8def43a345 Mike Kravetz 2017-02-22 369 if (vm_alloc_shared)
1c9e8def43a345 Mike Kravetz 2017-02-22 370 SetPagePrivate(page);
1c9e8def43a345 Mike Kravetz 2017-02-22 371 else
21205bf8f77b23 Mike Kravetz 2017-02-22 372 ClearPagePrivate(page);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 373 put_page(page);
21205bf8f77b23 Mike Kravetz 2017-02-22 374 }
60d4d2d2b40e44 Mike Kravetz 2017-02-22 375 BUG_ON(copied < 0);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 376 BUG_ON(err > 0);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 377 BUG_ON(!copied && !err);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 378 return copied ? copied : err;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 379 }
60d4d2d2b40e44 Mike Kravetz 2017-02-22 380 #else /* !CONFIG_HUGETLB_PAGE */
60d4d2d2b40e44 Mike Kravetz 2017-02-22 381 /* fail at build time if gcc attempts to use this */
60d4d2d2b40e44 Mike Kravetz 2017-02-22 382 extern ssize_t __mcopy_atomic_hugetlb(struct mm_struct *dst_mm,
60d4d2d2b40e44 Mike Kravetz 2017-02-22 383 struct vm_area_struct *dst_vma,
60d4d2d2b40e44 Mike Kravetz 2017-02-22 384 unsigned long dst_start,
60d4d2d2b40e44 Mike Kravetz 2017-02-22 385 unsigned long src_start,
60d4d2d2b40e44 Mike Kravetz 2017-02-22 386 unsigned long len,
60d4d2d2b40e44 Mike Kravetz 2017-02-22 387 bool zeropage);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 388 #endif /* CONFIG_HUGETLB_PAGE */
60d4d2d2b40e44 Mike Kravetz 2017-02-22 389
:::::: The code at line 262 was first introduced by commit
:::::: 60d4d2d2b40e44cd36bfb6049e8d9e2055a24f8a userfaultfd: hugetlbfs: add __mcopy_atomic_hugetlb for huge page UFFDIO_COPY
:::::: TO: Mike Kravetz <mike.kravetz@oracle.com>
:::::: CC: Linus Torvalds <torvalds@linux-foundation.org>
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 28633 bytes --]
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] hugetlb: remove unused hstate in hugetlb_fault_mutex_hash()
2019-10-05 0:33 ` [PATCH] hugetlb: remove unused hstate in hugetlb_fault_mutex_hash() Wei Yang
2019-10-05 5:42 ` kbuild test robot
2019-10-05 5:43 ` kbuild test robot
@ 2019-10-06 2:25 ` kbuild test robot
2 siblings, 0 replies; 4+ messages in thread
From: kbuild test robot @ 2019-10-06 2:25 UTC (permalink / raw)
To: Wei Yang
Cc: kbuild-all, mike.kravetz, akpm, hughd, aarcange, linux-mm,
linux-kernel, Wei Yang
Hi Wei,
Thank you for the patch! Perhaps something to improve:
[auto build test WARNING on linus/master]
[cannot apply to v5.4-rc1 next-20191004]
[if your patch is applied to the wrong git tree, please drop us a note to help
improve the system. BTW, we also suggest to use '--base' option to specify the
base tree in git format-patch, please see https://stackoverflow.com/a/37406982]
url: https://github.com/0day-ci/linux/commits/Wei-Yang/hugetlb-remove-unused-hstate-in-hugetlb_fault_mutex_hash/20191005-090034
reproduce:
# apt-get install sparse
# sparse version: v0.6.1-rc1-42-g38eda53-dirty
make ARCH=x86_64 allmodconfig
make C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__'
If you fix the issue, kindly add following tag
Reported-by: kbuild test robot <lkp@intel.com>
sparse warnings: (new ones prefixed by >>)
mm/userfaultfd.c:262:17: sparse: sparse: undefined identifier 'h'
mm/userfaultfd.c:273:75: sparse: sparse: undefined identifier 'h'
mm/userfaultfd.c:300:69: sparse: sparse: undefined identifier 'h'
>> mm/userfaultfd.c:262:17: sparse: sparse: incorrect type in argument 1 (different base types) @@ expected struct hstate *h @@ got hstate *h @@
>> mm/userfaultfd.c:262:17: sparse: expected struct hstate *h
>> mm/userfaultfd.c:262:17: sparse: got bad type
mm/userfaultfd.c:273:75: sparse: sparse: incorrect type in argument 1 (different base types) @@ expected struct hstate *h @@ got hstate *h @@
mm/userfaultfd.c:273:75: sparse: expected struct hstate *h
mm/userfaultfd.c:273:75: sparse: got bad type
mm/userfaultfd.c:300:69: sparse: sparse: incorrect type in argument 1 (different base types) @@ expected struct hstate *h @@ got hstate *h @@
mm/userfaultfd.c:300:69: sparse: expected struct hstate *h
mm/userfaultfd.c:300:69: sparse: got bad type
vim +262 mm/userfaultfd.c
c1a4de99fada21 Andrea Arcangeli 2015-09-04 167
60d4d2d2b40e44 Mike Kravetz 2017-02-22 168 #ifdef CONFIG_HUGETLB_PAGE
60d4d2d2b40e44 Mike Kravetz 2017-02-22 169 /*
60d4d2d2b40e44 Mike Kravetz 2017-02-22 170 * __mcopy_atomic processing for HUGETLB vmas. Note that this routine is
60d4d2d2b40e44 Mike Kravetz 2017-02-22 171 * called with mmap_sem held, it will release mmap_sem before returning.
60d4d2d2b40e44 Mike Kravetz 2017-02-22 172 */
60d4d2d2b40e44 Mike Kravetz 2017-02-22 173 static __always_inline ssize_t __mcopy_atomic_hugetlb(struct mm_struct *dst_mm,
60d4d2d2b40e44 Mike Kravetz 2017-02-22 174 struct vm_area_struct *dst_vma,
60d4d2d2b40e44 Mike Kravetz 2017-02-22 175 unsigned long dst_start,
60d4d2d2b40e44 Mike Kravetz 2017-02-22 176 unsigned long src_start,
60d4d2d2b40e44 Mike Kravetz 2017-02-22 177 unsigned long len,
60d4d2d2b40e44 Mike Kravetz 2017-02-22 178 bool zeropage)
60d4d2d2b40e44 Mike Kravetz 2017-02-22 179 {
1c9e8def43a345 Mike Kravetz 2017-02-22 180 int vm_alloc_shared = dst_vma->vm_flags & VM_SHARED;
1c9e8def43a345 Mike Kravetz 2017-02-22 181 int vm_shared = dst_vma->vm_flags & VM_SHARED;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 182 ssize_t err;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 183 pte_t *dst_pte;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 184 unsigned long src_addr, dst_addr;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 185 long copied;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 186 struct page *page;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 187 unsigned long vma_hpagesize;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 188 pgoff_t idx;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 189 u32 hash;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 190 struct address_space *mapping;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 191
60d4d2d2b40e44 Mike Kravetz 2017-02-22 192 /*
60d4d2d2b40e44 Mike Kravetz 2017-02-22 193 * There is no default zero huge page for all huge page sizes as
60d4d2d2b40e44 Mike Kravetz 2017-02-22 194 * supported by hugetlb. A PMD_SIZE huge pages may exist as used
60d4d2d2b40e44 Mike Kravetz 2017-02-22 195 * by THP. Since we can not reliably insert a zero page, this
60d4d2d2b40e44 Mike Kravetz 2017-02-22 196 * feature is not supported.
60d4d2d2b40e44 Mike Kravetz 2017-02-22 197 */
60d4d2d2b40e44 Mike Kravetz 2017-02-22 198 if (zeropage) {
60d4d2d2b40e44 Mike Kravetz 2017-02-22 199 up_read(&dst_mm->mmap_sem);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 200 return -EINVAL;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 201 }
60d4d2d2b40e44 Mike Kravetz 2017-02-22 202
60d4d2d2b40e44 Mike Kravetz 2017-02-22 203 src_addr = src_start;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 204 dst_addr = dst_start;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 205 copied = 0;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 206 page = NULL;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 207 vma_hpagesize = vma_kernel_pagesize(dst_vma);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 208
60d4d2d2b40e44 Mike Kravetz 2017-02-22 209 /*
60d4d2d2b40e44 Mike Kravetz 2017-02-22 210 * Validate alignment based on huge page size
60d4d2d2b40e44 Mike Kravetz 2017-02-22 211 */
60d4d2d2b40e44 Mike Kravetz 2017-02-22 212 err = -EINVAL;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 213 if (dst_start & (vma_hpagesize - 1) || len & (vma_hpagesize - 1))
60d4d2d2b40e44 Mike Kravetz 2017-02-22 214 goto out_unlock;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 215
60d4d2d2b40e44 Mike Kravetz 2017-02-22 216 retry:
60d4d2d2b40e44 Mike Kravetz 2017-02-22 217 /*
60d4d2d2b40e44 Mike Kravetz 2017-02-22 218 * On routine entry dst_vma is set. If we had to drop mmap_sem and
60d4d2d2b40e44 Mike Kravetz 2017-02-22 219 * retry, dst_vma will be set to NULL and we must lookup again.
60d4d2d2b40e44 Mike Kravetz 2017-02-22 220 */
60d4d2d2b40e44 Mike Kravetz 2017-02-22 221 if (!dst_vma) {
27d02568f529e9 Mike Rapoport 2017-02-24 222 err = -ENOENT;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 223 dst_vma = find_vma(dst_mm, dst_start);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 224 if (!dst_vma || !is_vm_hugetlb_page(dst_vma))
60d4d2d2b40e44 Mike Kravetz 2017-02-22 225 goto out_unlock;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 226 /*
29ec90660d68bb Andrea Arcangeli 2018-11-30 227 * Check the vma is registered in uffd, this is
29ec90660d68bb Andrea Arcangeli 2018-11-30 228 * required to enforce the VM_MAYWRITE check done at
29ec90660d68bb Andrea Arcangeli 2018-11-30 229 * uffd registration time.
60d4d2d2b40e44 Mike Kravetz 2017-02-22 230 */
27d02568f529e9 Mike Rapoport 2017-02-24 231 if (!dst_vma->vm_userfaultfd_ctx.ctx)
27d02568f529e9 Mike Rapoport 2017-02-24 232 goto out_unlock;
27d02568f529e9 Mike Rapoport 2017-02-24 233
60d4d2d2b40e44 Mike Kravetz 2017-02-22 234 if (dst_start < dst_vma->vm_start ||
60d4d2d2b40e44 Mike Kravetz 2017-02-22 235 dst_start + len > dst_vma->vm_end)
60d4d2d2b40e44 Mike Kravetz 2017-02-22 236 goto out_unlock;
1c9e8def43a345 Mike Kravetz 2017-02-22 237
27d02568f529e9 Mike Rapoport 2017-02-24 238 err = -EINVAL;
27d02568f529e9 Mike Rapoport 2017-02-24 239 if (vma_hpagesize != vma_kernel_pagesize(dst_vma))
27d02568f529e9 Mike Rapoport 2017-02-24 240 goto out_unlock;
27d02568f529e9 Mike Rapoport 2017-02-24 241
1c9e8def43a345 Mike Kravetz 2017-02-22 242 vm_shared = dst_vma->vm_flags & VM_SHARED;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 243 }
60d4d2d2b40e44 Mike Kravetz 2017-02-22 244
60d4d2d2b40e44 Mike Kravetz 2017-02-22 245 if (WARN_ON(dst_addr & (vma_hpagesize - 1) ||
60d4d2d2b40e44 Mike Kravetz 2017-02-22 246 (len - copied) & (vma_hpagesize - 1)))
60d4d2d2b40e44 Mike Kravetz 2017-02-22 247 goto out_unlock;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 248
60d4d2d2b40e44 Mike Kravetz 2017-02-22 249 /*
1c9e8def43a345 Mike Kravetz 2017-02-22 250 * If not shared, ensure the dst_vma has a anon_vma.
60d4d2d2b40e44 Mike Kravetz 2017-02-22 251 */
60d4d2d2b40e44 Mike Kravetz 2017-02-22 252 err = -ENOMEM;
1c9e8def43a345 Mike Kravetz 2017-02-22 253 if (!vm_shared) {
60d4d2d2b40e44 Mike Kravetz 2017-02-22 254 if (unlikely(anon_vma_prepare(dst_vma)))
60d4d2d2b40e44 Mike Kravetz 2017-02-22 255 goto out_unlock;
1c9e8def43a345 Mike Kravetz 2017-02-22 256 }
60d4d2d2b40e44 Mike Kravetz 2017-02-22 257
60d4d2d2b40e44 Mike Kravetz 2017-02-22 258 while (src_addr < src_start + len) {
60d4d2d2b40e44 Mike Kravetz 2017-02-22 259 pte_t dst_pteval;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 260
60d4d2d2b40e44 Mike Kravetz 2017-02-22 261 BUG_ON(dst_addr >= dst_start + len);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 @262 VM_BUG_ON(dst_addr & ~huge_page_mask(h));
60d4d2d2b40e44 Mike Kravetz 2017-02-22 263
60d4d2d2b40e44 Mike Kravetz 2017-02-22 264 /*
ddeaab32a89f04 Mike Kravetz 2019-01-08 265 * Serialize via hugetlb_fault_mutex
60d4d2d2b40e44 Mike Kravetz 2017-02-22 266 */
b43a9990055958 Mike Kravetz 2018-12-28 267 idx = linear_page_index(dst_vma, dst_addr);
ddeaab32a89f04 Mike Kravetz 2019-01-08 268 mapping = dst_vma->vm_file->f_mapping;
2b52c262f0e75d Wei Yang 2019-10-05 269 hash = hugetlb_fault_mutex_hash(mapping, idx, dst_addr);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 270 mutex_lock(&hugetlb_fault_mutex_table[hash]);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 271
60d4d2d2b40e44 Mike Kravetz 2017-02-22 272 err = -ENOMEM;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 273 dst_pte = huge_pte_alloc(dst_mm, dst_addr, huge_page_size(h));
60d4d2d2b40e44 Mike Kravetz 2017-02-22 274 if (!dst_pte) {
60d4d2d2b40e44 Mike Kravetz 2017-02-22 275 mutex_unlock(&hugetlb_fault_mutex_table[hash]);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 276 goto out_unlock;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 277 }
60d4d2d2b40e44 Mike Kravetz 2017-02-22 278
60d4d2d2b40e44 Mike Kravetz 2017-02-22 279 err = -EEXIST;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 280 dst_pteval = huge_ptep_get(dst_pte);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 281 if (!huge_pte_none(dst_pteval)) {
60d4d2d2b40e44 Mike Kravetz 2017-02-22 282 mutex_unlock(&hugetlb_fault_mutex_table[hash]);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 283 goto out_unlock;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 284 }
60d4d2d2b40e44 Mike Kravetz 2017-02-22 285
60d4d2d2b40e44 Mike Kravetz 2017-02-22 286 err = hugetlb_mcopy_atomic_pte(dst_mm, dst_pte, dst_vma,
60d4d2d2b40e44 Mike Kravetz 2017-02-22 287 dst_addr, src_addr, &page);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 288
60d4d2d2b40e44 Mike Kravetz 2017-02-22 289 mutex_unlock(&hugetlb_fault_mutex_table[hash]);
1c9e8def43a345 Mike Kravetz 2017-02-22 290 vm_alloc_shared = vm_shared;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 291
60d4d2d2b40e44 Mike Kravetz 2017-02-22 292 cond_resched();
60d4d2d2b40e44 Mike Kravetz 2017-02-22 293
9e368259ad9883 Andrea Arcangeli 2018-11-30 294 if (unlikely(err == -ENOENT)) {
60d4d2d2b40e44 Mike Kravetz 2017-02-22 295 up_read(&dst_mm->mmap_sem);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 296 BUG_ON(!page);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 297
60d4d2d2b40e44 Mike Kravetz 2017-02-22 298 err = copy_huge_page_from_user(page,
60d4d2d2b40e44 Mike Kravetz 2017-02-22 299 (const void __user *)src_addr,
810a56b943e265 Mike Kravetz 2017-02-22 300 pages_per_huge_page(h), true);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 301 if (unlikely(err)) {
60d4d2d2b40e44 Mike Kravetz 2017-02-22 302 err = -EFAULT;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 303 goto out;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 304 }
60d4d2d2b40e44 Mike Kravetz 2017-02-22 305 down_read(&dst_mm->mmap_sem);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 306
60d4d2d2b40e44 Mike Kravetz 2017-02-22 307 dst_vma = NULL;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 308 goto retry;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 309 } else
60d4d2d2b40e44 Mike Kravetz 2017-02-22 310 BUG_ON(page);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 311
60d4d2d2b40e44 Mike Kravetz 2017-02-22 312 if (!err) {
60d4d2d2b40e44 Mike Kravetz 2017-02-22 313 dst_addr += vma_hpagesize;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 314 src_addr += vma_hpagesize;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 315 copied += vma_hpagesize;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 316
60d4d2d2b40e44 Mike Kravetz 2017-02-22 317 if (fatal_signal_pending(current))
60d4d2d2b40e44 Mike Kravetz 2017-02-22 318 err = -EINTR;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 319 }
60d4d2d2b40e44 Mike Kravetz 2017-02-22 320 if (err)
60d4d2d2b40e44 Mike Kravetz 2017-02-22 321 break;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 322 }
60d4d2d2b40e44 Mike Kravetz 2017-02-22 323
60d4d2d2b40e44 Mike Kravetz 2017-02-22 324 out_unlock:
60d4d2d2b40e44 Mike Kravetz 2017-02-22 325 up_read(&dst_mm->mmap_sem);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 326 out:
21205bf8f77b23 Mike Kravetz 2017-02-22 327 if (page) {
21205bf8f77b23 Mike Kravetz 2017-02-22 328 /*
21205bf8f77b23 Mike Kravetz 2017-02-22 329 * We encountered an error and are about to free a newly
1c9e8def43a345 Mike Kravetz 2017-02-22 330 * allocated huge page.
1c9e8def43a345 Mike Kravetz 2017-02-22 331 *
1c9e8def43a345 Mike Kravetz 2017-02-22 332 * Reservation handling is very subtle, and is different for
1c9e8def43a345 Mike Kravetz 2017-02-22 333 * private and shared mappings. See the routine
1c9e8def43a345 Mike Kravetz 2017-02-22 334 * restore_reserve_on_error for details. Unfortunately, we
1c9e8def43a345 Mike Kravetz 2017-02-22 335 * can not call restore_reserve_on_error now as it would
1c9e8def43a345 Mike Kravetz 2017-02-22 336 * require holding mmap_sem.
1c9e8def43a345 Mike Kravetz 2017-02-22 337 *
1c9e8def43a345 Mike Kravetz 2017-02-22 338 * If a reservation for the page existed in the reservation
1c9e8def43a345 Mike Kravetz 2017-02-22 339 * map of a private mapping, the map was modified to indicate
1c9e8def43a345 Mike Kravetz 2017-02-22 340 * the reservation was consumed when the page was allocated.
1c9e8def43a345 Mike Kravetz 2017-02-22 341 * We clear the PagePrivate flag now so that the global
21205bf8f77b23 Mike Kravetz 2017-02-22 342 * reserve count will not be incremented in free_huge_page.
21205bf8f77b23 Mike Kravetz 2017-02-22 343 * The reservation map will still indicate the reservation
21205bf8f77b23 Mike Kravetz 2017-02-22 344 * was consumed and possibly prevent later page allocation.
1c9e8def43a345 Mike Kravetz 2017-02-22 345 * This is better than leaking a global reservation. If no
1c9e8def43a345 Mike Kravetz 2017-02-22 346 * reservation existed, it is still safe to clear PagePrivate
1c9e8def43a345 Mike Kravetz 2017-02-22 347 * as no adjustments to reservation counts were made during
1c9e8def43a345 Mike Kravetz 2017-02-22 348 * allocation.
1c9e8def43a345 Mike Kravetz 2017-02-22 349 *
1c9e8def43a345 Mike Kravetz 2017-02-22 350 * The reservation map for shared mappings indicates which
1c9e8def43a345 Mike Kravetz 2017-02-22 351 * pages have reservations. When a huge page is allocated
1c9e8def43a345 Mike Kravetz 2017-02-22 352 * for an address with a reservation, no change is made to
1c9e8def43a345 Mike Kravetz 2017-02-22 353 * the reserve map. In this case PagePrivate will be set
1c9e8def43a345 Mike Kravetz 2017-02-22 354 * to indicate that the global reservation count should be
1c9e8def43a345 Mike Kravetz 2017-02-22 355 * incremented when the page is freed. This is the desired
1c9e8def43a345 Mike Kravetz 2017-02-22 356 * behavior. However, when a huge page is allocated for an
1c9e8def43a345 Mike Kravetz 2017-02-22 357 * address without a reservation a reservation entry is added
1c9e8def43a345 Mike Kravetz 2017-02-22 358 * to the reservation map, and PagePrivate will not be set.
1c9e8def43a345 Mike Kravetz 2017-02-22 359 * When the page is freed, the global reserve count will NOT
1c9e8def43a345 Mike Kravetz 2017-02-22 360 * be incremented and it will appear as though we have leaked
1c9e8def43a345 Mike Kravetz 2017-02-22 361 * reserved page. In this case, set PagePrivate so that the
1c9e8def43a345 Mike Kravetz 2017-02-22 362 * global reserve count will be incremented to match the
1c9e8def43a345 Mike Kravetz 2017-02-22 363 * reservation map entry which was created.
1c9e8def43a345 Mike Kravetz 2017-02-22 364 *
1c9e8def43a345 Mike Kravetz 2017-02-22 365 * Note that vm_alloc_shared is based on the flags of the vma
1c9e8def43a345 Mike Kravetz 2017-02-22 366 * for which the page was originally allocated. dst_vma could
1c9e8def43a345 Mike Kravetz 2017-02-22 367 * be different or NULL on error.
21205bf8f77b23 Mike Kravetz 2017-02-22 368 */
1c9e8def43a345 Mike Kravetz 2017-02-22 369 if (vm_alloc_shared)
1c9e8def43a345 Mike Kravetz 2017-02-22 370 SetPagePrivate(page);
1c9e8def43a345 Mike Kravetz 2017-02-22 371 else
21205bf8f77b23 Mike Kravetz 2017-02-22 372 ClearPagePrivate(page);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 373 put_page(page);
21205bf8f77b23 Mike Kravetz 2017-02-22 374 }
60d4d2d2b40e44 Mike Kravetz 2017-02-22 375 BUG_ON(copied < 0);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 376 BUG_ON(err > 0);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 377 BUG_ON(!copied && !err);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 378 return copied ? copied : err;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 379 }
60d4d2d2b40e44 Mike Kravetz 2017-02-22 380 #else /* !CONFIG_HUGETLB_PAGE */
60d4d2d2b40e44 Mike Kravetz 2017-02-22 381 /* fail at build time if gcc attempts to use this */
60d4d2d2b40e44 Mike Kravetz 2017-02-22 382 extern ssize_t __mcopy_atomic_hugetlb(struct mm_struct *dst_mm,
60d4d2d2b40e44 Mike Kravetz 2017-02-22 383 struct vm_area_struct *dst_vma,
60d4d2d2b40e44 Mike Kravetz 2017-02-22 384 unsigned long dst_start,
60d4d2d2b40e44 Mike Kravetz 2017-02-22 385 unsigned long src_start,
60d4d2d2b40e44 Mike Kravetz 2017-02-22 386 unsigned long len,
60d4d2d2b40e44 Mike Kravetz 2017-02-22 387 bool zeropage);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 388 #endif /* CONFIG_HUGETLB_PAGE */
60d4d2d2b40e44 Mike Kravetz 2017-02-22 389
:::::: The code at line 262 was first introduced by commit
:::::: 60d4d2d2b40e44cd36bfb6049e8d9e2055a24f8a userfaultfd: hugetlbfs: add __mcopy_atomic_hugetlb for huge page UFFDIO_COPY
:::::: TO: Mike Kravetz <mike.kravetz@oracle.com>
:::::: CC: Linus Torvalds <torvalds@linux-foundation.org>
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
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2019-10-05 0:33 ` [PATCH] hugetlb: remove unused hstate in hugetlb_fault_mutex_hash() Wei Yang
2019-10-05 5:42 ` kbuild test robot
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