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Author SHA1 Message Date
Kees Cook 42bc47b353 treewide: Use array_size() in vmalloc() 
The vmalloc() function has no 2-factor argument form, so multiplication
factors need to be wrapped in array_size(). This patch replaces cases of:

        vmalloc(a * b)

with:
        vmalloc(array_size(a, b))

as well as handling cases of:

        vmalloc(a * b * c)

with:

        vmalloc(array3_size(a, b, c))

This does, however, attempt to ignore constant size factors like:

        vmalloc(4 * 1024)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
type TYPE;
expression THING, E;
@@

(
  vmalloc(
-	(sizeof(TYPE)) * E
+	sizeof(TYPE) * E
  , ...)
|
  vmalloc(
-	(sizeof(THING)) * E
+	sizeof(THING) * E
  , ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression COUNT;
typedef u8;
typedef __u8;
@@

(
  vmalloc(
-	sizeof(u8) * (COUNT)
+	COUNT
  , ...)
|
  vmalloc(
-	sizeof(__u8) * (COUNT)
+	COUNT
  , ...)
|
  vmalloc(
-	sizeof(char) * (COUNT)
+	COUNT
  , ...)
|
  vmalloc(
-	sizeof(unsigned char) * (COUNT)
+	COUNT
  , ...)
|
  vmalloc(
-	sizeof(u8) * COUNT
+	COUNT
  , ...)
|
  vmalloc(
-	sizeof(__u8) * COUNT
+	COUNT
  , ...)
|
  vmalloc(
-	sizeof(char) * COUNT
+	COUNT
  , ...)
|
  vmalloc(
-	sizeof(unsigned char) * COUNT
+	COUNT
  , ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
  vmalloc(
-	sizeof(TYPE) * (COUNT_ID)
+	array_size(COUNT_ID, sizeof(TYPE))
  , ...)
|
  vmalloc(
-	sizeof(TYPE) * COUNT_ID
+	array_size(COUNT_ID, sizeof(TYPE))
  , ...)
|
  vmalloc(
-	sizeof(TYPE) * (COUNT_CONST)
+	array_size(COUNT_CONST, sizeof(TYPE))
  , ...)
|
  vmalloc(
-	sizeof(TYPE) * COUNT_CONST
+	array_size(COUNT_CONST, sizeof(TYPE))
  , ...)
|
  vmalloc(
-	sizeof(THING) * (COUNT_ID)
+	array_size(COUNT_ID, sizeof(THING))
  , ...)
|
  vmalloc(
-	sizeof(THING) * COUNT_ID
+	array_size(COUNT_ID, sizeof(THING))
  , ...)
|
  vmalloc(
-	sizeof(THING) * (COUNT_CONST)
+	array_size(COUNT_CONST, sizeof(THING))
  , ...)
|
  vmalloc(
-	sizeof(THING) * COUNT_CONST
+	array_size(COUNT_CONST, sizeof(THING))
  , ...)
)

// 2-factor product, only identifiers.
@@
identifier SIZE, COUNT;
@@

  vmalloc(
-	SIZE * COUNT
+	array_size(COUNT, SIZE)
  , ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
  vmalloc(
-	sizeof(TYPE) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  vmalloc(
-	sizeof(TYPE) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  vmalloc(
-	sizeof(TYPE) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  vmalloc(
-	sizeof(TYPE) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  vmalloc(
-	sizeof(THING) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  vmalloc(
-	sizeof(THING) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  vmalloc(
-	sizeof(THING) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  vmalloc(
-	sizeof(THING) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
  vmalloc(
-	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  vmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  vmalloc(
-	sizeof(THING1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  vmalloc(
-	sizeof(THING1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  vmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
|
  vmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
identifier STRIDE, SIZE, COUNT;
@@

(
  vmalloc(
-	(COUNT) * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  vmalloc(
-	COUNT * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  vmalloc(
-	COUNT * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  vmalloc(
-	(COUNT) * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  vmalloc(
-	COUNT * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  vmalloc(
-	(COUNT) * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  vmalloc(
-	(COUNT) * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  vmalloc(
-	COUNT * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
)

// Any remaining multi-factor products, first at least 3-factor products
// when they're not all constants...
@@
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
  vmalloc(C1 * C2 * C3, ...)
|
  vmalloc(
-	E1 * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
)

// And then all remaining 2 factors products when they're not all constants.
@@
expression E1, E2;
constant C1, C2;
@@

(
  vmalloc(C1 * C2, ...)
|
  vmalloc(
-	E1 * E2
+	array_size(E1, E2)
  , ...)
)

Signed-off-by: Kees Cook <keescook@chromium.org>
 2018-06-12 16:19:22 -07:00
Kees Cook 778e1cdd81 treewide: kvzalloc() -> kvcalloc() 
The kvzalloc() function has a 2-factor argument form, kvcalloc(). This
patch replaces cases of:

        kvzalloc(a * b, gfp)

with:
        kvcalloc(a * b, gfp)

as well as handling cases of:

        kvzalloc(a * b * c, gfp)

with:

        kvzalloc(array3_size(a, b, c), gfp)

as it's slightly less ugly than:

        kvcalloc(array_size(a, b), c, gfp)

This does, however, attempt to ignore constant size factors like:

        kvzalloc(4 * 1024, gfp)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
type TYPE;
expression THING, E;
@@

(
  kvzalloc(
-	(sizeof(TYPE)) * E
+	sizeof(TYPE) * E
  , ...)
|
  kvzalloc(
-	(sizeof(THING)) * E
+	sizeof(THING) * E
  , ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression COUNT;
typedef u8;
typedef __u8;
@@

(
  kvzalloc(
-	sizeof(u8) * (COUNT)
+	COUNT
  , ...)
|
  kvzalloc(
-	sizeof(__u8) * (COUNT)
+	COUNT
  , ...)
|
  kvzalloc(
-	sizeof(char) * (COUNT)
+	COUNT
  , ...)
|
  kvzalloc(
-	sizeof(unsigned char) * (COUNT)
+	COUNT
  , ...)
|
  kvzalloc(
-	sizeof(u8) * COUNT
+	COUNT
  , ...)
|
  kvzalloc(
-	sizeof(__u8) * COUNT
+	COUNT
  , ...)
|
  kvzalloc(
-	sizeof(char) * COUNT
+	COUNT
  , ...)
|
  kvzalloc(
-	sizeof(unsigned char) * COUNT
+	COUNT
  , ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
- kvzalloc
+ kvcalloc
  (
-	sizeof(TYPE) * (COUNT_ID)
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kvzalloc
+ kvcalloc
  (
-	sizeof(TYPE) * COUNT_ID
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kvzalloc
+ kvcalloc
  (
-	sizeof(TYPE) * (COUNT_CONST)
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kvzalloc
+ kvcalloc
  (
-	sizeof(TYPE) * COUNT_CONST
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kvzalloc
+ kvcalloc
  (
-	sizeof(THING) * (COUNT_ID)
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kvzalloc
+ kvcalloc
  (
-	sizeof(THING) * COUNT_ID
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kvzalloc
+ kvcalloc
  (
-	sizeof(THING) * (COUNT_CONST)
+	COUNT_CONST, sizeof(THING)
  , ...)
|
- kvzalloc
+ kvcalloc
  (
-	sizeof(THING) * COUNT_CONST
+	COUNT_CONST, sizeof(THING)
  , ...)
)

// 2-factor product, only identifiers.
@@
identifier SIZE, COUNT;
@@

- kvzalloc
+ kvcalloc
  (
-	SIZE * COUNT
+	COUNT, SIZE
  , ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
  kvzalloc(
-	sizeof(TYPE) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kvzalloc(
-	sizeof(TYPE) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kvzalloc(
-	sizeof(TYPE) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kvzalloc(
-	sizeof(TYPE) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kvzalloc(
-	sizeof(THING) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kvzalloc(
-	sizeof(THING) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kvzalloc(
-	sizeof(THING) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kvzalloc(
-	sizeof(THING) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
  kvzalloc(
-	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kvzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kvzalloc(
-	sizeof(THING1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kvzalloc(
-	sizeof(THING1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kvzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
|
  kvzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
identifier STRIDE, SIZE, COUNT;
@@

(
  kvzalloc(
-	(COUNT) * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kvzalloc(
-	COUNT * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kvzalloc(
-	COUNT * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kvzalloc(
-	(COUNT) * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kvzalloc(
-	COUNT * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kvzalloc(
-	(COUNT) * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kvzalloc(
-	(COUNT) * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kvzalloc(
-	COUNT * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
)

// Any remaining multi-factor products, first at least 3-factor products,
// when they're not all constants...
@@
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
  kvzalloc(C1 * C2 * C3, ...)
|
  kvzalloc(
-	(E1) * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kvzalloc(
-	(E1) * (E2) * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kvzalloc(
-	(E1) * (E2) * (E3)
+	array3_size(E1, E2, E3)
  , ...)
|
  kvzalloc(
-	E1 * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
)

// And then all remaining 2 factors products when they're not all constants,
// keeping sizeof() as the second factor argument.
@@
expression THING, E1, E2;
type TYPE;
constant C1, C2, C3;
@@

(
  kvzalloc(sizeof(THING) * C2, ...)
|
  kvzalloc(sizeof(TYPE) * C2, ...)
|
  kvzalloc(C1 * C2 * C3, ...)
|
  kvzalloc(C1 * C2, ...)
|
- kvzalloc
+ kvcalloc
  (
-	sizeof(TYPE) * (E2)
+	E2, sizeof(TYPE)
  , ...)
|
- kvzalloc
+ kvcalloc
  (
-	sizeof(TYPE) * E2
+	E2, sizeof(TYPE)
  , ...)
|
- kvzalloc
+ kvcalloc
  (
-	sizeof(THING) * (E2)
+	E2, sizeof(THING)
  , ...)
|
- kvzalloc
+ kvcalloc
  (
-	sizeof(THING) * E2
+	E2, sizeof(THING)
  , ...)
|
- kvzalloc
+ kvcalloc
  (
-	(E1) * E2
+	E1, E2
  , ...)
|
- kvzalloc
+ kvcalloc
  (
-	(E1) * (E2)
+	E1, E2
  , ...)
|
- kvzalloc
+ kvcalloc
  (
-	E1 * E2
+	E1, E2
  , ...)
)

Signed-off-by: Kees Cook <keescook@chromium.org>
 2018-06-12 16:19:22 -07:00
Kees Cook 6396bb2215 treewide: kzalloc() -> kcalloc() 
The kzalloc() function has a 2-factor argument form, kcalloc(). This
patch replaces cases of:

        kzalloc(a * b, gfp)

with:
        kcalloc(a * b, gfp)

as well as handling cases of:

        kzalloc(a * b * c, gfp)

with:

        kzalloc(array3_size(a, b, c), gfp)

as it's slightly less ugly than:

        kzalloc_array(array_size(a, b), c, gfp)

This does, however, attempt to ignore constant size factors like:

        kzalloc(4 * 1024, gfp)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
type TYPE;
expression THING, E;
@@

(
  kzalloc(
-	(sizeof(TYPE)) * E
+	sizeof(TYPE) * E
  , ...)
|
  kzalloc(
-	(sizeof(THING)) * E
+	sizeof(THING) * E
  , ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression COUNT;
typedef u8;
typedef __u8;
@@

(
  kzalloc(
-	sizeof(u8) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(__u8) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(char) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(unsigned char) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(u8) * COUNT
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(__u8) * COUNT
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(char) * COUNT
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(unsigned char) * COUNT
+	COUNT
  , ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * (COUNT_ID)
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * COUNT_ID
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * (COUNT_CONST)
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * COUNT_CONST
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * (COUNT_ID)
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * COUNT_ID
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * (COUNT_CONST)
+	COUNT_CONST, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * COUNT_CONST
+	COUNT_CONST, sizeof(THING)
  , ...)
)

// 2-factor product, only identifiers.
@@
identifier SIZE, COUNT;
@@

- kzalloc
+ kcalloc
  (
-	SIZE * COUNT
+	COUNT, SIZE
  , ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
  kzalloc(
-	sizeof(TYPE) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(TYPE) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(TYPE) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(TYPE) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(THING) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kzalloc(
-	sizeof(THING) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kzalloc(
-	sizeof(THING) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kzalloc(
-	sizeof(THING) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
  kzalloc(
-	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kzalloc(
-	sizeof(THING1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kzalloc(
-	sizeof(THING1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
|
  kzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
identifier STRIDE, SIZE, COUNT;
@@

(
  kzalloc(
-	(COUNT) * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	(COUNT) * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	(COUNT) * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	(COUNT) * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
)

// Any remaining multi-factor products, first at least 3-factor products,
// when they're not all constants...
@@
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
  kzalloc(C1 * C2 * C3, ...)
|
  kzalloc(
-	(E1) * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kzalloc(
-	(E1) * (E2) * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kzalloc(
-	(E1) * (E2) * (E3)
+	array3_size(E1, E2, E3)
  , ...)
|
  kzalloc(
-	E1 * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
)

// And then all remaining 2 factors products when they're not all constants,
// keeping sizeof() as the second factor argument.
@@
expression THING, E1, E2;
type TYPE;
constant C1, C2, C3;
@@

(
  kzalloc(sizeof(THING) * C2, ...)
|
  kzalloc(sizeof(TYPE) * C2, ...)
|
  kzalloc(C1 * C2 * C3, ...)
|
  kzalloc(C1 * C2, ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * (E2)
+	E2, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * E2
+	E2, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * (E2)
+	E2, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * E2
+	E2, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	(E1) * E2
+	E1, E2
  , ...)
|
- kzalloc
+ kcalloc
  (
-	(E1) * (E2)
+	E1, E2
  , ...)
|
- kzalloc
+ kcalloc
  (
-	E1 * E2
+	E1, E2
  , ...)
)

Signed-off-by: Kees Cook <keescook@chromium.org>
 2018-06-12 16:19:22 -07:00
Kees Cook 6da2ec5605 treewide: kmalloc() -> kmalloc_array() 
The kmalloc() function has a 2-factor argument form, kmalloc_array(). This
patch replaces cases of:

        kmalloc(a * b, gfp)

with:
        kmalloc_array(a * b, gfp)

as well as handling cases of:

        kmalloc(a * b * c, gfp)

with:

        kmalloc(array3_size(a, b, c), gfp)

as it's slightly less ugly than:

        kmalloc_array(array_size(a, b), c, gfp)

This does, however, attempt to ignore constant size factors like:

        kmalloc(4 * 1024, gfp)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

The tools/ directory was manually excluded, since it has its own
implementation of kmalloc().

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
type TYPE;
expression THING, E;
@@

(
  kmalloc(
-	(sizeof(TYPE)) * E
+	sizeof(TYPE) * E
  , ...)
|
  kmalloc(
-	(sizeof(THING)) * E
+	sizeof(THING) * E
  , ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression COUNT;
typedef u8;
typedef __u8;
@@

(
  kmalloc(
-	sizeof(u8) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(__u8) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(char) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(unsigned char) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(u8) * COUNT
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(__u8) * COUNT
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(char) * COUNT
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(unsigned char) * COUNT
+	COUNT
  , ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * (COUNT_ID)
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * COUNT_ID
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * (COUNT_CONST)
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * COUNT_CONST
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * (COUNT_ID)
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * COUNT_ID
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * (COUNT_CONST)
+	COUNT_CONST, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * COUNT_CONST
+	COUNT_CONST, sizeof(THING)
  , ...)
)

// 2-factor product, only identifiers.
@@
identifier SIZE, COUNT;
@@

- kmalloc
+ kmalloc_array
  (
-	SIZE * COUNT
+	COUNT, SIZE
  , ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
  kmalloc(
-	sizeof(TYPE) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(TYPE) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(TYPE) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(TYPE) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(THING) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kmalloc(
-	sizeof(THING) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kmalloc(
-	sizeof(THING) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kmalloc(
-	sizeof(THING) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
  kmalloc(
-	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kmalloc(
-	sizeof(THING1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kmalloc(
-	sizeof(THING1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
|
  kmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
identifier STRIDE, SIZE, COUNT;
@@

(
  kmalloc(
-	(COUNT) * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	(COUNT) * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	(COUNT) * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	(COUNT) * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
)

// Any remaining multi-factor products, first at least 3-factor products,
// when they're not all constants...
@@
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
  kmalloc(C1 * C2 * C3, ...)
|
  kmalloc(
-	(E1) * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kmalloc(
-	(E1) * (E2) * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kmalloc(
-	(E1) * (E2) * (E3)
+	array3_size(E1, E2, E3)
  , ...)
|
  kmalloc(
-	E1 * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
)

// And then all remaining 2 factors products when they're not all constants,
// keeping sizeof() as the second factor argument.
@@
expression THING, E1, E2;
type TYPE;
constant C1, C2, C3;
@@

(
  kmalloc(sizeof(THING) * C2, ...)
|
  kmalloc(sizeof(TYPE) * C2, ...)
|
  kmalloc(C1 * C2 * C3, ...)
|
  kmalloc(C1 * C2, ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * (E2)
+	E2, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * E2
+	E2, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * (E2)
+	E2, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * E2
+	E2, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	(E1) * E2
+	E1, E2
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	(E1) * (E2)
+	E1, E2
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	E1 * E2
+	E1, E2
  , ...)
)

Signed-off-by: Kees Cook <keescook@chromium.org>
 2018-06-12 16:19:22 -07:00
Linus Torvalds 7d3bf613e9 libnvdimm for 4.18 
* DAX broke a fundamental assumption of truncate of file mapped pages.
   The truncate path assumed that it is safe to disconnect a pinned page
   from a file and let the filesystem reclaim the physical block. With DAX
   the page is equivalent to the filesystem block. Introduce
   dax_layout_busy_page() to enable filesystems to wait for pinned DAX
   pages to be released. Without this wait a filesystem could allocate
   blocks under active device-DMA to a new file.
 
 * DAX arranges for the block layer to be bypassed and uses
   dax_direct_access() + copy_to_iter() to satisfy read(2) calls.
   However, the memcpy_mcsafe() facility is available through the pmem
   block driver. In order to safely handle media errors, via the DAX
   block-layer bypass, introduce copy_to_iter_mcsafe().
 
 * Fix cache management policy relative to the ACPI NFIT Platform
   Capabilities Structure to properly elide cache flushes when they are not
   necessary. The table indicates whether CPU caches are power-fail
   protected. Clarify that a deep flush is always performed on
   REQ_{FUA,PREFLUSH} requests.
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Merge tag 'libnvdimm-for-4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull libnvdimm updates from Dan Williams:
 "This adds a user for the new 'bytes-remaining' updates to
  memcpy_mcsafe() that you already received through Ingo via the
  x86-dax- for-linus pull.

  Not included here, but still targeting this cycle, is support for
  handling memory media errors (poison) consumed via userspace dax
  mappings.

  Summary:

   - DAX broke a fundamental assumption of truncate of file mapped
     pages. The truncate path assumed that it is safe to disconnect a
     pinned page from a file and let the filesystem reclaim the physical
     block. With DAX the page is equivalent to the filesystem block.
     Introduce dax_layout_busy_page() to enable filesystems to wait for
     pinned DAX pages to be released. Without this wait a filesystem
     could allocate blocks under active device-DMA to a new file.

   - DAX arranges for the block layer to be bypassed and uses
     dax_direct_access() + copy_to_iter() to satisfy read(2) calls.
     However, the memcpy_mcsafe() facility is available through the pmem
     block driver. In order to safely handle media errors, via the DAX
     block-layer bypass, introduce copy_to_iter_mcsafe().

   - Fix cache management policy relative to the ACPI NFIT Platform
     Capabilities Structure to properly elide cache flushes when they
     are not necessary. The table indicates whether CPU caches are
     power-fail protected. Clarify that a deep flush is always performed
     on REQ_{FUA,PREFLUSH} requests"

* tag 'libnvdimm-for-4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (21 commits)
  dax: Use dax_write_cache* helpers
  libnvdimm, pmem: Do not flush power-fail protected CPU caches
  libnvdimm, pmem: Unconditionally deep flush on *sync
  libnvdimm, pmem: Complete REQ_FLUSH => REQ_PREFLUSH
  acpi, nfit: Remove ecc_unit_size
  dax: dax_insert_mapping_entry always succeeds
  libnvdimm, e820: Register all pmem resources
  libnvdimm: Debug probe times
  linvdimm, pmem: Preserve read-only setting for pmem devices
  x86, nfit_test: Add unit test for memcpy_mcsafe()
  pmem: Switch to copy_to_iter_mcsafe()
  dax: Report bytes remaining in dax_iomap_actor()
  dax: Introduce a ->copy_to_iter dax operation
  uio, lib: Fix CONFIG_ARCH_HAS_UACCESS_MCSAFE compilation
  xfs, dax: introduce xfs_break_dax_layouts()
  xfs: prepare xfs_break_layouts() for another layout type
  xfs: prepare xfs_break_layouts() to be called with XFS_MMAPLOCK_EXCL
  mm, fs, dax: handle layout changes to pinned dax mappings
  mm: fix __gup_device_huge vs unmap
  mm: introduce MEMORY_DEVICE_FS_DAX and CONFIG_DEV_PAGEMAP_OPS
  ...
 2018-06-08 17:21:52 -07:00
Dan Williams b56845794e Merge branch 'for-4.18/dax' into libnvdimm-for-next 2018-06-08 15:16:40 -07:00
Linus Torvalds 68abbe7295 Merge branch 'akpm' (patches from Andrew) 
Merge updates from Andrew Morton:

 - a few misc things

 - ocfs2 updates

 - v9fs updates

 - MM

 - procfs updates

 - lib/ updates

 - autofs updates

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (118 commits)
  autofs: small cleanup in autofs_getpath()
  autofs: clean up includes
  autofs: comment on selinux changes needed for module autoload
  autofs: update MAINTAINERS entry for autofs
  autofs: use autofs instead of autofs4 in documentation
  autofs: rename autofs documentation files
  autofs: create autofs Kconfig and Makefile
  autofs: delete fs/autofs4 source files
  autofs: update fs/autofs4/Makefile
  autofs: update fs/autofs4/Kconfig
  autofs: copy autofs4 to autofs
  autofs4: use autofs instead of autofs4 everywhere
  autofs4: merge auto_fs.h and auto_fs4.h
  fs/binfmt_misc.c: do not allow offset overflow
  checkpatch: improve patch recognition
  lib/ucs2_string.c: add MODULE_LICENSE()
  lib/mpi: headers cleanup
  lib/percpu_ida.c: use _irqsave() instead of local_irq_save() + spin_lock
  lib/idr.c: remove simple_ida_lock
  lib/bitmap.c: micro-optimization for __bitmap_complement()
  ...
 2018-06-07 18:39:37 -07:00
Michal Hocko ce91f6ee5b mm: kvmalloc does not fallback to vmalloc for incompatible gfp flags 
kvmalloc warned about incompatible gfp_mask to catch abusers (mostly
GFP_NOFS) with an intention that this will motivate authors of the code
to fix those.  Linus argues that this just motivates people to do even
more hacks like

	if (gfp == GFP_KERNEL)
		kvmalloc
	else
		kmalloc

I haven't seen this happening much (Linus pointed to bucket_lock special
cases an atomic allocation but my git foo hasn't found much more) but it
is true that we can grow those in future.  Therefore Linus suggested to
simply not fallback to vmalloc for incompatible gfp flags and rather
stick with the kmalloc path.

Link: http://lkml.kernel.org/r/20180601115329.27807-1-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Tom Herbert <tom@quantonium.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:38 -07:00
Kirill A. Shutemov daa280753c mm/shmem.c: zero out unused vma fields in shmem_pseudo_vma_init() 
shmem/tmpfs uses pseudo vma to allocate page with correct NUMA policy.

The pseudo vma doesn't have vm_page_prot set.  We are going to encode
encryption KeyID in vm_page_prot.  Having garbage there causes problems.

Zero out all unused fields in the pseudo vma.

Link: http://lkml.kernel.org/r/20180531135602.20321-1-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:38 -07:00
Vlastimil Babka 7810e6781e mm, page_alloc: do not break __GFP_THISNODE by zonelist reset 
In __alloc_pages_slowpath() we reset zonelist and preferred_zoneref for
allocations that can ignore memory policies.  The zonelist is obtained
from current CPU's node.  This is a problem for __GFP_THISNODE
allocations that want to allocate on a different node, e.g.  because the
allocating thread has been migrated to a different CPU.

This has been observed to break SLAB in our 4.4-based kernel, because
there it relies on __GFP_THISNODE working as intended.  If a slab page
is put on wrong node's list, then further list manipulations may corrupt
the list because page_to_nid() is used to determine which node's
list_lock should be locked and thus we may take a wrong lock and race.

Current SLAB implementation seems to be immune by luck thanks to commit
511e3a0588 ("mm/slab: make cache_grow() handle the page allocated on
arbitrary node") but there may be others assuming that __GFP_THISNODE
works as promised.

We can fix it by simply removing the zonelist reset completely.  There
is actually no reason to reset it, because memory policies and cpusets
don't affect the zonelist choice in the first place.  This was different
when commit 183f6371aa ("mm: ignore mempolicies when using
ALLOC_NO_WATERMARK") introduced the code, as mempolicies provided their
own restricted zonelists.

We might consider this for 4.17 although I don't know if there's
anything currently broken.

SLAB is currently not affected, but in kernels older than 4.7 that don't
yet have 511e3a0588 ("mm/slab: make cache_grow() handle the page
allocated on arbitrary node") it is.  That's at least 4.4 LTS.  Older
ones I'll have to check.

So stable backports should be more important, but will have to be
reviewed carefully, as the code went through many changes.  BTW I think
that also the ac->preferred_zoneref reset is currently useless if we
don't also reset ac->nodemask from a mempolicy to NULL first (which we
probably should for the OOM victims etc?), but I would leave that for a
separate patch.

Link: http://lkml.kernel.org/r/20180525130853.13915-1-vbabka@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Fixes: 183f6371aa ("mm: ignore mempolicies when using ALLOC_NO_WATERMARK")
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:38 -07:00
Mike Rapoport df2cc96e77 userfaultfd: prevent non-cooperative events vs mcopy_atomic races 
If a process monitored with userfaultfd changes it's memory mappings or
forks() at the same time as uffd monitor fills the process memory with
UFFDIO_COPY, the actual creation of page table entries and copying of
the data in mcopy_atomic may happen either before of after the memory
mapping modifications and there is no way for the uffd monitor to
maintain consistent view of the process memory layout.

For instance, let's consider fork() running in parallel with
userfaultfd_copy():

process        		         |	uffd monitor
---------------------------------+------------------------------
fork()        		         | userfaultfd_copy()
...        		         | ...
    dup_mmap()        	         |     down_read(mmap_sem)
    down_write(mmap_sem)         |     /* create PTEs, copy data */
        dup_uffd()               |     up_read(mmap_sem)
        copy_page_range()        |
        up_write(mmap_sem)       |
        dup_uffd_complete()      |
            /* notify monitor */ |

If the userfaultfd_copy() takes the mmap_sem first, the new page(s) will
be present by the time copy_page_range() is called and they will appear
in the child's memory mappings.  However, if the fork() is the first to
take the mmap_sem, the new pages won't be mapped in the child's address
space.

If the pages are not present and child tries to access them, the monitor
will get page fault notification and everything is fine.  However, if
the pages *are present*, the child can access them without uffd
noticing.  And if we copy them into child it'll see the wrong data.
Since we are talking about background copy, we'd need to decide whether
the pages should be copied or not regardless #PF notifications.

Since userfaultfd monitor has no way to determine what was the order,
let's disallow userfaultfd_copy in parallel with the non-cooperative
events.  In such case we return -EAGAIN and the uffd monitor can
understand that userfaultfd_copy() clashed with a non-cooperative event
and take an appropriate action.

Link: http://lkml.kernel.org/r/1527061324-19949-1-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Acked-by: Pavel Emelyanov <xemul@virtuozzo.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Andrei Vagin <avagin@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:38 -07:00
Tejun Heo be09102b41 mm: memcg: allow lowering memory.swap.max below the current usage 
Currently an attempt to set swap.max into a value lower than the actual
swap usage fails, which causes configuration problems as there's no way
of lowering the configuration below the current usage short of turning
off swap entirely.  This makes swap.max difficult to use and allows
delegatees to lock the delegator out of reducing swap allocation.

This patch updates swap_max_write() so that the limit can be lowered
below the current usage.  It doesn't implement active reclaiming of swap
entries for the following reasons.

* mem_cgroup_swap_full() already tells the swap machinary to
  aggressively reclaim swap entries if the usage is above 50% of
  limit, so simply lowering the limit automatically triggers gradual
  reclaim.

* Forcing back swapped out pages is likely to heavily impact the
  workload and mess up the working set.  Given that swap usually is a
  lot less valuable and less scarce, letting the existing usage
  dissipate over time through the above gradual reclaim and as they're
  falted back in is likely the better behavior.

Link: http://lkml.kernel.org/r/20180523185041.GR1718769@devbig577.frc2.facebook.com
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Roman Gushchin <guro@fb.com>
Acked-by: Rik van Riel <riel@surriel.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Shaohua Li <shli@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:37 -07:00
Souptick Joarder 20acce6799 mm/shmem.c: use new return type vm_fault_t 
Use new return type vm_fault_t for fault handler.  For now, this is just
documenting that the function returns a VM_FAULT value rather than an
errno.  Once all instances are converted, vm_fault_t will become a
distinct type.

See commit 1c8f422059 ("mm: change return type to vm_fault_t")

vmf_error() is the newly introduce inline function in 4.17-rc6.

Link: http://lkml.kernel.org/r/20180521202410.GA17912@jordon-HP-15-Notebook-PC
Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:37 -07:00
Matthew Wilcox 325d7d4a96 slub: remove 'reserved' file from sysfs 
Christoph doubts anyone was using the 'reserved' file in sysfs, so remove
it.

Link: http://lkml.kernel.org/r/20180518194519.3820-17-willy@infradead.org
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:37 -07:00
Matthew Wilcox 9736d2a95e slub: remove kmem_cache->reserved 
The reserved field was only used for embedding an rcu_head in the data
structure.  With the previous commit, we no longer need it.  That lets us
remove the 'reserved' argument to a lot of functions.

Link: http://lkml.kernel.org/r/20180518194519.3820-16-willy@infradead.org
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:37 -07:00
Matthew Wilcox bf68c214df slab,slub: remove rcu_head size checks 
rcu_head may now grow larger than list_head without affecting slab or
slub.

Link: http://lkml.kernel.org/r/20180518194519.3820-15-willy@infradead.org
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Acked-by: Christoph Lameter <cl@linux.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:37 -07:00
Matthew Wilcox 4da1984edb mm: combine LRU and main union in struct page 
This gives us five words of space in a single union in struct page.  The
compound_mapcount moves position (from offset 24 to offset 20) on 64-bit
systems, but that does not seem likely to cause any trouble.

Link: http://lkml.kernel.org/r/20180518194519.3820-11-willy@infradead.org
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:37 -07:00
Matthew Wilcox b7ccc7f8c6 mm: move lru union within struct page 
Since the LRU is two words, this does not affect the double-word alignment
of SLUB's freelist.

Link: http://lkml.kernel.org/r/20180518194519.3820-10-willy@infradead.org
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:37 -07:00
Matthew Wilcox fa3015b7ee mm: use page->deferred_list 
Now that we can represent the location of 'deferred_list' in C instead of
comments, make use of that ability.

Link: http://lkml.kernel.org/r/20180518194519.3820-9-willy@infradead.org
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:37 -07:00
Matthew Wilcox 7d27a04bb2 mm: move 'private' union within struct page 
By moving page->private to the fourth word of struct page, we can put the
SLUB counters in the same word as SLAB's s_mem and still do the
cmpxchg_double trick.  Now the SLUB counters no longer overlap with the
mapcount or refcount so we can drop the call to page_mapcount_reset() and
simplify set_page_slub_counters() to a single line.

Link: http://lkml.kernel.org/r/20180518194519.3820-6-willy@infradead.org
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:37 -07:00
Matthew Wilcox d4fc5069a3 mm: switch s_mem and slab_cache in struct page 
This will allow us to store slub's counters in the same bits as slab's
s_mem.  slub now needs to set page->mapping to NULL as it frees the page,
just like slab does.

Link: http://lkml.kernel.org/r/20180518194519.3820-5-willy@infradead.org
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Acked-by: Christoph Lameter <cl@linux.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:37 -07:00
Matthew Wilcox 6e292b9be7 mm: split page_type out from _mapcount 
We're already using a union of many fields here, so stop abusing the
_mapcount and make page_type its own field.  That implies renaming some of
the machinery that creates PageBuddy, PageBalloon and PageKmemcg; bring
back the PG_buddy, PG_balloon and PG_kmemcg names.

As suggested by Kirill, make page_type a bitmask.  Because it starts out
life as -1 (thanks to sharing the storage with _mapcount), setting a page
flag means clearing the appropriate bit.  This gives us space for probably
twenty or so extra bits (depending how paranoid we want to be about
_mapcount underflow).

Link: http://lkml.kernel.org/r/20180518194519.3820-3-willy@infradead.org
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Christoph Lameter <cl@linux.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:37 -07:00
Huang Ying 285b8dcaac mm, hugetlbfs: pass fault address to no page handler 
This is to take better advantage of general huge page clearing
optimization (commit c79b57e462b5: "mm: hugetlb: clear target sub-page
last when clearing huge page") for hugetlbfs.

In the general optimization patch, the sub-page to access will be
cleared last to avoid the cache lines of to access sub-page to be
evicted when clearing other sub-pages.  This works better if we have the
address of the sub-page to access, that is, the fault address inside the
huge page.  So the hugetlbfs no page fault handler is changed to pass
that information.  This will benefit workloads which don't access the
begin of the hugetlbfs huge page after the page fault under heavy cache
contention for shared last level cache.

The patch is a generic optimization which should benefit quite some
workloads, not for a specific use case.  To demonstrate the performance
benefit of the patch, we tested it with vm-scalability run on hugetlbfs.

With this patch, the throughput increases ~28.1% in vm-scalability
anon-w-seq test case with 88 processes on a 2 socket Xeon E5 2699 v4
system (44 cores, 88 threads).  The test case creates 88 processes, each
process mmaps a big anonymous memory area with MAP_HUGETLB and writes to
it from the end to the begin.  For each process, other processes could
be seen as other workload which generates heavy cache pressure.  At the
same time, the cache miss rate reduced from ~36.3% to ~25.6%, the IPC
(instruction per cycle) increased from 0.3 to 0.37, and the time spent
in user space is reduced ~19.3%.

Link: http://lkml.kernel.org/r/20180517083539.9242-1-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andi Kleen <andi.kleen@intel.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Shaohua Li <shli@fb.com>
Cc: Christopher Lameter <cl@linux.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Punit Agrawal <punit.agrawal@arm.com>
Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:36 -07:00
Souptick Joarder b3ec9f33ac mm: change return type to vm_fault_t 
Use new return type vm_fault_t for fault handler in struct
vm_operations_struct.  For now, this is just documenting that the
function returns a VM_FAULT value rather than an errno.  Once all
instances are converted, vm_fault_t will become a distinct type.

See commit 1c8f422059 ("mm: change return type to vm_fault_t")

Link: http://lkml.kernel.org/r/20180512063745.GA26866@jordon-HP-15-Notebook-PC
Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Joe Perches <joe@perches.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:36 -07:00
Souptick Joarder 2bcd6454ba mm: use new return type vm_fault_t 
Use new return type vm_fault_t for fault handler in struct
vm_operations_struct.  For now, this is just documenting that the
function returns a VM_FAULT value rather than an errno.  Once all
instances are converted, vm_fault_t will become a distinct type.

Link: http://lkml.kernel.org/r/20180511190542.GA2412@jordon-HP-15-Notebook-PC
Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Pavel Tatashin <pasha.tatashin@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:36 -07:00
Huaisheng Ye a380b40abb mm/page_alloc.c: remove useless parameter of finalise_ac() 
finalise_ac() has parameter order which is not used at all.  Remove it.

Signed-off-by: Huaisheng Ye <yehs1@lenovo.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:36 -07:00
Andy Shevchenko 3cadfa2b94 mm/vmpressure.c: convert to use match_string() helper 
The new helper returns index of the matching string in an array.  We are
going to use it here.

Link: http://lkml.kernel.org/r/20180503203206.44046-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:36 -07:00
Andy Shevchenko d62ff365b8 mm/vmpressure.c: use kstrndup instead of kmalloc+strncpy 
Using kstrndup() simplifies the code.

Link: http://lkml.kernel.org/r/20180503201807.24941-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:36 -07:00
Roman Gushchin bf8d5d52ff memcg: introduce memory.min 
Memory controller implements the memory.low best-effort memory
protection mechanism, which works perfectly in many cases and allows
protecting working sets of important workloads from sudden reclaim.

But its semantics has a significant limitation: it works only as long as
there is a supply of reclaimable memory.  This makes it pretty useless
against any sort of slow memory leaks or memory usage increases.  This
is especially true for swapless systems.  If swap is enabled, memory
soft protection effectively postpones problems, allowing a leaking
application to fill all swap area, which makes no sense.  The only
effective way to guarantee the memory protection in this case is to
invoke the OOM killer.

It's possible to handle this case in userspace by reacting on MEMCG_LOW
events; but there is still a place for a fail-safe in-kernel mechanism
to provide stronger guarantees.

This patch introduces the memory.min interface for cgroup v2 memory
controller.  It works very similarly to memory.low (sharing the same
hierarchical behavior), except that it's not disabled if there is no
more reclaimable memory in the system.

If cgroup is not populated, its memory.min is ignored, because otherwise
even the OOM killer wouldn't be able to reclaim the protected memory,
and the system can stall.

[guro@fb.com: s/low/min/ in docs]
Link: http://lkml.kernel.org/r/20180510130758.GA9129@castle.DHCP.thefacebook.com
Link: http://lkml.kernel.org/r/20180509180734.GA4856@castle.DHCP.thefacebook.com
Signed-off-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:36 -07:00
Mathieu Malaterre fb52bbaee5 mm: move is_pageblock_removable_nolock() to mm/memory_hotplug.c 
is_pageblock_removable_nolock() is not used outside of
mm/memory_hotplug.c.  Move it next to unique caller
is_mem_section_removable() and make it static.

Remove prototype in <linux/memory_hotplug.h> to silence gcc warning (W=1):

  mm/page_alloc.c:7704:6: warning: no previous prototype for `is_pageblock_removable_nolock' [-Wmissing-prototypes]

Link: http://lkml.kernel.org/r/20180509190001.24789-1-malat@debian.org
Signed-off-by: Mathieu Malaterre <malat@debian.org>
Suggested-by: Michal Hocko <mhocko@kernel.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:36 -07:00
Minchan Kim 25cf23d7a9 mm/memblock: print memblock_remove 
memblock_remove report is useful to see why MemTotal of /proc/meminfo
between two kernels makes difference.

Link: http://lkml.kernel.org/r/20180508104223.8028-1-minchan@kernel.org
Signed-off-by: Minchan Kim <minchan@kernel.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:36 -07:00
Junaid Shahid d12c60f64c mm: memcontrol: drain memcg stock on force_empty 
The per-cpu memcg stock can retain a charge of upto 32 pages.  On a
machine with large number of cpus, this can amount to a decent amount of
memory.  Additionally force_empty interface might be triggering unneeded
memcg reclaims.

Link: http://lkml.kernel.org/r/20180507201651.165879-1-shakeelb@google.com
Signed-off-by: Junaid Shahid <junaids@google.com>
Signed-off-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:36 -07:00
Shakeel Butt bb4a7ea2b1 mm: memcontrol: drain stocks on resize limit 
Resizing the memcg limit for cgroup-v2 drains the stocks before
triggering the memcg reclaim.  Do the same for cgroup-v1 to make the
behavior consistent.

Link: http://lkml.kernel.org/r/20180504205548.110696-1-shakeelb@google.com
Signed-off-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:36 -07:00
Greg Thelen 8dd53fd3b7 memcg: mark memcg1_events static const 
Mark memcg1_events static: it's only used by memcontrol.c.  And mark it
const: it's not modified.

Link: http://lkml.kernel.org/r/20180503192940.94971-1-gthelen@google.com
Signed-off-by: Greg Thelen <gthelen@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:36 -07:00
Wang Long 9ccc361716 memcg: writeback: use memcg->cgwb_list directly 
mem_cgroup_cgwb_list is a very simple wrapper and it will never be used
outside of code under CONFIG_CGROUP_WRITEBACK.  so use memcg->cgwb_list
directly.

Link: http://lkml.kernel.org/r/1524406173-212182-1-git-send-email-wanglong19@meituan.com
Signed-off-by: Wang Long <wanglong19@meituan.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:36 -07:00
Amir Goldstein 12ba780d64 tmpfs: allow decoding a file handle of an unlinked file 
tmpfs uses the helper d_find_alias() to find a dentry from a decoded
inode, but d_find_alias() skips unhashed dentries, so unlinked files
cannot be decoded from a file handle.

This can be reproduced using xfstests test program open_by_handle:

  $ open_by handle -c /tmp/testdir
  $ open_by_handle -dk /tmp/testdir
  open_by_handle(/tmp/testdir/file000000) returned 116 incorrectly on an unlinked open file!

To fix this, if d_find_alias() can't find a hashed alias, call
d_find_any_alias() to return an unhashed one.

Link: http://lkml.kernel.org/r/CAOQ4uxg+qSLP0KwdW+h1tcPqOCQd+_pGZVXiePQB1TXCMBMctQ@mail.gmail.com
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: NeilBrown <neilb@suse.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jeff Layton <jlayton@poochiereds.net>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:36 -07:00
Mike Rapoport 88484826bc mm/ksm: move [set_]page_stable_node from ksm.h to ksm.c 
page_stable_node() and set_page_stable_node() are only used in mm/ksm.c
and there is no point to keep them in the include/linux/ksm.h

[akpm@linux-foundation.org: fix SYSFS=n build]
Link: http://lkml.kernel.org/r/1524552106-7356-3-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:36 -07:00
Omar Sandoval 93781325da lockdep: fix fs_reclaim annotation 
While revisiting my Btrfs swapfile series [1], I introduced a situation
in which reclaim would lock i_rwsem, and even though the swapon() path
clearly made GFP_KERNEL allocations while holding i_rwsem, I got no
complaints from lockdep.  It turns out that the rework of the fs_reclaim
annotation was broken: if the current task has PF_MEMALLOC set, we don't
acquire the dummy fs_reclaim lock, but when reclaiming we always check
this _after_ we've just set the PF_MEMALLOC flag.  In most cases, we can
fix this by moving the fs_reclaim_{acquire,release}() outside of the
memalloc_noreclaim_{save,restore}(), althought kswapd is slightly
different.  After applying this, I got the expected lockdep splats.

1: https://lwn.net/Articles/625412/

Link: http://lkml.kernel.org/r/9f8aa70652a98e98d7c4de0fc96a4addcee13efe.1523778026.git.osandov@fb.com
Fixes: d92a8cfcb3 ("locking/lockdep: Rework FS_RECLAIM annotation")
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:35 -07:00
Yang Shi 89fdcd262f mm: shmem: make stat.st_blksize return huge page size if THP is on 
Since tmpfs THP was supported in 4.8, hugetlbfs is not the only
filesystem with huge page support anymore.  tmpfs can use huge page via
THP when mounting by "huge=" mount option.

When applications use huge page on hugetlbfs, it just need check the
filesystem magic number, but it is not enough for tmpfs.  Make
stat.st_blksize return huge page size if it is mounted by appropriate
"huge=" option to give applications a hint to optimize the behavior with
THP.

Some applications may not do wisely with THP.  For example, QEMU may
mmap file on non huge page aligned hint address with MAP_FIXED, which
results in no pages are PMD mapped even though THP is used.  Some
applications may mmap file with non huge page aligned offset.  Both
behaviors make THP pointless.

statfs.f_bsize still returns 4KB for tmpfs since THP could be split, and
it also may fallback to 4KB page silently if there is not enough huge
page.  Furthermore, different f_bsize makes max_blocks and free_blocks
calculation harder but without too much benefit.  Returning huge page
size via stat.st_blksize sounds good enough.

Since PUD size huge page for THP has not been supported, now it just
returns HPAGE_PMD_SIZE.

Hugh said:

: Sorry, I have no enthusiasm for this patch; but do I feel strongly
: enough to override you and everyone else to NAK it?  No, I don't feel
: that strongly, maybe st_blksize isn't worth arguing over.
:
: We did look at struct stat when designing huge tmpfs, to see if there
: were any fields that should be adjusted for it; but concluded none.
: Yes, it would sometimes be nice to have a quickly accessible indicator
: for when tmpfs has been mounted huge (scanning /proc/mounts for options
: can be tiresome, agreed); but since tmpfs tries to supply huge (or not)
: pages transparently, no difference seemed right.
:
: So, because st_blksize is a not very useful field of struct stat, with
: "size" in the name, we're going to put HPAGE_PMD_SIZE in there instead
: of PAGE_SIZE, if the tmpfs was mounted with one of the huge "huge"
: options (force or always, okay; within_size or advise, not so much).
: Though HPAGE_PMD_SIZE is no more its "preferred I/O size" or "blocksize
: for file system I/O" than PAGE_SIZE was.
:
: Which we can expect to speed up some applications and disadvantage
: others, depending on how they interpret st_blksize: just like if we
: changed it in the same way on non-huge tmpfs.  (Did I actually try
: changing st_blksize early on, and find it broke something?  If so, I've
: now forgotten what, and a search through commit messages didn't find
: it; but I guess we'll find out soon enough.)
:
: If there were an mstat() syscall, returning a field "preferred
: alignment", then we could certainly agree to put HPAGE_PMD_SIZE in
: there; but in stat()'s st_blksize?  And what happens when (in future)
: mm maps this or that hard-disk filesystem's blocks with a pmd mapping -
: should that filesystem then advertise a bigger st_blksize, despite the
: same disk layout as before?  What happens with DAX?
:
: And this change is not going to help the QEMU suboptimality that
: brought you here (or does QEMU align mmaps according to st_blksize?).
: QEMU ought to work well with kernels without this change, and kernels
: with this change; and I hope it can easily deal with both by avoiding
: that use of MAP_FIXED which prevented the kernel's intended alignment.

[akpm@linux-foundation.org: remove unneeded `else']
Link: http://lkml.kernel.org/r/1524665633-83806-1-git-send-email-yang.shi@linux.alibaba.com
Signed-off-by: Yang Shi <yang.shi@linux.alibaba.com>
Suggested-by: Christoph Hellwig <hch@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:35 -07:00
Chintan Pandya 05e3ff9505 mm: vmalloc: pass proper vm_start into debugobjects 
Client can call vunmap with some intermediate 'addr' which may not be
the start of the VM area.  Entire unmap code works with vm->vm_start
which is proper but debug object API is called with 'addr'.  This could
be a problem within debug objects.

Pass proper start address into debug object API.

[akpm@linux-foundation.org: fix warning]
Link: http://lkml.kernel.org/r/1523961828-9485-3-git-send-email-cpandya@codeaurora.org
Signed-off-by: Chintan Pandya <cpandya@codeaurora.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Byungchul Park <byungchul.park@lge.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Yisheng Xie <xieyisheng1@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:35 -07:00
Chintan Pandya f3c01d2f3a mm: vmalloc: avoid racy handling of debugobjects in vunmap 
Currently, __vunmap flow is,
 1) Release the VM area
 2) Free the debug objects corresponding to that vm area.

This leave some race window open.
 1) Release the VM area
 1.5) Some other client gets the same vm area
 1.6) This client allocates new debug objects on the same
      vm area
 2) Free the debug objects corresponding to this vm area.

Here, we actually free 'other' client's debug objects.

Fix this by freeing the debug objects first and then releasing the VM
area.

Link: http://lkml.kernel.org/r/1523961828-9485-2-git-send-email-cpandya@codeaurora.org
Signed-off-by: Chintan Pandya <cpandya@codeaurora.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Byungchul Park <byungchul.park@lge.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Yisheng Xie <xieyisheng1@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:35 -07:00
Chintan Pandya 82a2e924ff mm: vmalloc: clean up vunmap to avoid pgtable ops twice 
vunmap does page table clear operations twice in the case when
DEBUG_PAGEALLOC_ENABLE_DEFAULT is enabled.

So, clean up the code as that is unintended.

As a perf gain, we save few us.  Below ftrace data was obtained while
doing 1 MB of vmalloc/vfree on ARM64 based SoC *without* this patch
applied.  After this patch, we can save ~3 us (on 1 extra
vunmap_page_range).

  CPU  DURATION                  FUNCTION CALLS
  |     |   |                     |   |   |   |
 6)               |  __vunmap() {
 6)               |    vmap_debug_free_range() {
 6)   3.281 us    |      vunmap_page_range();
 6) + 45.468 us   |    }
 6)   2.760 us    |    vunmap_page_range();
 6) ! 505.105 us  |  }

[cpandya@codeaurora.org: v3]
  Link: http://lkml.kernel.org/r/1525176960-18408-1-git-send-email-cpandya@codeaurora.org
Link: http://lkml.kernel.org/r/1523876342-10545-1-git-send-email-cpandya@codeaurora.org
Signed-off-by: Chintan Pandya <cpandya@codeaurora.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Yisheng Xie <xieyisheng1@huawei.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Byungchul Park <byungchul.park@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:35 -07:00
Wei Yang 08994b2467 mm/sparse.c: pass the __highest_present_section_nr + 1 to alloc_func() 
In commit c4e1be9ec1 ("mm, sparsemem: break out of loops early")
__highest_present_section_nr is introduced to reduce the loop counts for
present section.  This is also helpful for usemap and memmap allocation.

This patch uses __highest_present_section_nr + 1 to optimize the loop.

Link: http://lkml.kernel.org/r/20180326081956.75275-1-richard.weiyang@gmail.com
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:35 -07:00
Wei Yang d538c164fc mm/sparse.c: check __highest_present_section_nr only for a present section 
When searching a present section, there are two boundaries:

    * __highest_present_section_nr
    * NR_MEM_SECTIONS

And it is known, __highest_present_section_nr is a more strict boundary
than NR_MEM_SECTIONS.  This means it would be necessary to check
__highest_present_section_nr only.

Link: http://lkml.kernel.org/r/20180326081956.75275-2-richard.weiyang@gmail.com
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Acked-by: David Rientjes <rientjes@google.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:35 -07:00
Huang Ying 688272809f mm, gup: prevent pmd checking race in follow_pmd_mask() 
mmap_sem will be read locked when calling follow_pmd_mask().  But this
cannot prevent PMD from being changed for all cases when PTL is
unlocked, for example, from pmd_trans_huge() to pmd_none() via
MADV_DONTNEED.  So it is possible for the pmd_present() check in
follow_pmd_mask() to encounter an invalid PMD.  This may cause an
incorrect VM_BUG_ON() or an infinite loop.  Fix this by reading the PMD
entry into a local variable with READ_ONCE() and checking the local
variable and pmd_none() in the retry loop.

As Kirill pointed out, with PTL unlocked, the *pmd may be changed under
us, so reading it directly again and again may incur weird bugs.  So
although using *pmd directly other than for pmd_present() checking may
be safe, it is still better to replace them to read *pmd once and check
the local variable multiple times.

When PTL unlocked, replace all *pmd with local variable was suggested by
Kirill.

Link: http://lkml.kernel.org/r/20180419083514.1365-1-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: Zi Yan <zi.yan@cs.rutgers.edu>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:35 -07:00
Roman Gushchin 5f93ad6743 mm: treat memory.low value inclusive 
If memcg's usage is equal to the memory.low value, avoid reclaiming from
this cgroup while there is a surplus of reclaimable memory.

This sounds more logical and also matches memory.high and memory.max
behavior: both are inclusive.

Empty cgroups are not considered protected, so MEMCG_LOW events are not
emitted for empty cgroups, if there is no more reclaimable memory in the
system.

Link: http://lkml.kernel.org/r/20180406122132.GA7185@castle
Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:35 -07:00
Roman Gushchin 230671533d mm: memory.low hierarchical behavior 
This patch aims to address an issue in current memory.low semantics,
which makes it hard to use it in a hierarchy, where some leaf memory
cgroups are more valuable than others.

For example, there are memcgs A, A/B, A/C, A/D and A/E:

  A      A/memory.low = 2G, A/memory.current = 6G
 //\\
BC  DE   B/memory.low = 3G  B/memory.current = 2G
         C/memory.low = 1G  C/memory.current = 2G
         D/memory.low = 0   D/memory.current = 2G
	 E/memory.low = 10G E/memory.current = 0

If we apply memory pressure, B, C and D are reclaimed at the same pace
while A's usage exceeds 2G.  This is obviously wrong, as B's usage is
fully below B's memory.low, and C has 1G of protection as well.  Also, A
is pushed to the size, which is less than A's 2G memory.low, which is
also wrong.

A simple bash script (provided below) can be used to reproduce
the problem. Current results are:
  A:    1430097920
  A/B:  711929856
  A/C:  717426688
  A/D:  741376
  A/E:  0

To address the issue a concept of effective memory.low is introduced.
Effective memory.low is always equal or less than original memory.low.
In a case, when there is no memory.low overcommittment (and also for
top-level cgroups), these two values are equal.

Otherwise it's a part of parent's effective memory.low, calculated as a
cgroup's memory.low usage divided by sum of sibling's memory.low usages
(under memory.low usage I mean the size of actually protected memory:
memory.current if memory.current < memory.low, 0 otherwise).  It's
necessary to track the actual usage, because otherwise an empty cgroup
with memory.low set (A/E in my example) will affect actual memory
distribution, which makes no sense.  To avoid traversing the cgroup tree
twice, page_counters code is reused.

Calculating effective memory.low can be done in the reclaim path, as we
conveniently traversing the cgroup tree from top to bottom and check
memory.low on each level.  So, it's a perfect place to calculate
effective memory low and save it to use it for children cgroups.

This also eliminates a need to traverse the cgroup tree from bottom to
top each time to check if parent's guarantee is not exceeded.

Setting/resetting effective memory.low is intentionally racy, but it's
fine and shouldn't lead to any significant differences in actual memory
distribution.

With this patch applied results are matching the expectations:
  A:    2147930112
  A/B:  1428721664
  A/C:  718393344
  A/D:  815104
  A/E:  0

Test script:
  #!/bin/bash

  CGPATH="/sys/fs/cgroup"

  truncate /file1 --size 2G
  truncate /file2 --size 2G
  truncate /file3 --size 2G
  truncate /file4 --size 50G

  mkdir "${CGPATH}/A"
  echo "+memory" > "${CGPATH}/A/cgroup.subtree_control"
  mkdir "${CGPATH}/A/B" "${CGPATH}/A/C" "${CGPATH}/A/D" "${CGPATH}/A/E"

  echo 2G > "${CGPATH}/A/memory.low"
  echo 3G > "${CGPATH}/A/B/memory.low"
  echo 1G > "${CGPATH}/A/C/memory.low"
  echo 0 > "${CGPATH}/A/D/memory.low"
  echo 10G > "${CGPATH}/A/E/memory.low"

  echo $$ > "${CGPATH}/A/B/cgroup.procs" && vmtouch -qt /file1
  echo $$ > "${CGPATH}/A/C/cgroup.procs" && vmtouch -qt /file2
  echo $$ > "${CGPATH}/A/D/cgroup.procs" && vmtouch -qt /file3
  echo $$ > "${CGPATH}/cgroup.procs" && vmtouch -qt /file4

  echo "A:   " `cat "${CGPATH}/A/memory.current"`
  echo "A/B: " `cat "${CGPATH}/A/B/memory.current"`
  echo "A/C: " `cat "${CGPATH}/A/C/memory.current"`
  echo "A/D: " `cat "${CGPATH}/A/D/memory.current"`
  echo "A/E: " `cat "${CGPATH}/A/E/memory.current"`

  rmdir "${CGPATH}/A/B" "${CGPATH}/A/C" "${CGPATH}/A/D" "${CGPATH}/A/E"
  rmdir "${CGPATH}/A"
  rm /file1 /file2 /file3 /file4

Link: http://lkml.kernel.org/r/20180405185921.4942-2-guro@fb.com
Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:35 -07:00
Roman Gushchin bbec2e1517 mm: rename page_counter's count/limit into usage/max 
This patch renames struct page_counter fields:
  count -> usage
  limit -> max

and the corresponding functions:
  page_counter_limit() -> page_counter_set_max()
  mem_cgroup_get_limit() -> mem_cgroup_get_max()
  mem_cgroup_resize_limit() -> mem_cgroup_resize_max()
  memcg_update_kmem_limit() -> memcg_update_kmem_max()
  memcg_update_tcp_limit() -> memcg_update_tcp_max()

The idea behind this renaming is to have the direct matching
between memory cgroup knobs (low, high, max) and page_counters API.

This is pure renaming, this patch doesn't bring any functional change.

Link: http://lkml.kernel.org/r/20180405185921.4942-1-guro@fb.com
Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:35 -07:00
Stefan Agner 1c4bc43ddf mm/memblock: introduce PHYS_ADDR_MAX 
So far code was using ULLONG_MAX and type casting to obtain a
phys_addr_t with all bits set.  The typecast is necessary to silence
compiler warnings on 32-bit platforms.

Use the simpler but still type safe approach "~(phys_addr_t)0" to create a
preprocessor define for all bits set.

Link: http://lkml.kernel.org/r/20180406213809.566-1-stefan@agner.ch
Signed-off-by: Stefan Agner <stefan@agner.ch>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Pavel Tatashin <pasha.tatashin@oracle.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:35 -07:00
Laurent Dufour 00b3a331fd mm: remove odd HAVE_PTE_SPECIAL 
Remove the additional define HAVE_PTE_SPECIAL and rely directly on
CONFIG_ARCH_HAS_PTE_SPECIAL.

There is no functional change introduced by this patch

Link: http://lkml.kernel.org/r/1523533733-25437-1-git-send-email-ldufour@linux.vnet.ibm.com
Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com>
Acked-by: David Rientjes <rientjes@google.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Christophe LEROY <christophe.leroy@c-s.fr>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2018-06-07 17:34:35 -07:00