Re: [PATCH v3] mm: Create the new vm_fault_t type
On Tue, Jan 8, 2019 at 4:14 AM Andrew Morton wrote: > > On Mon, 7 Jan 2019 11:47:12 +0530 Souptick Joarder > wrote: > > > > Do I need to make any further improvement for this patch ? > > > > If no further comment, can we get this patch in queue for 5.0-rcX ? > > I stopped paying attention a while ago, sorry. > > Please resend everything which you believe is ready to go. Sure, I will resend. no prob :)
Re: [PATCH v3] mm: Create the new vm_fault_t type
On Mon, 7 Jan 2019 11:47:12 +0530 Souptick Joarder wrote: > > Do I need to make any further improvement for this patch ? > > If no further comment, can we get this patch in queue for 5.0-rcX ? I stopped paying attention a while ago, sorry. Please resend everything which you believe is ready to go.
Re: [PATCH v3] mm: Create the new vm_fault_t type
On Fri, Dec 14, 2018 at 10:35 AM Souptick Joarder wrote:
>
> Hi Andrew,
>
> On Sat, Nov 24, 2018 at 10:16 AM Souptick Joarder
> wrote:
> >
> > On Thu, Nov 15, 2018 at 7:17 AM Mike Rapoport wrote:
> > >
> > > On Tue, Nov 06, 2018 at 05:36:42PM +0530, Souptick Joarder wrote:
> > > > Page fault handlers are supposed to return VM_FAULT codes,
> > > > but some drivers/file systems mistakenly return error
> > > > numbers. Now that all drivers/file systems have been converted
> > > > to use the vm_fault_t return type, change the type definition
> > > > to no longer be compatible with 'int'. By making it an unsigned
> > > > int, the function prototype becomes incompatible with a function
> > > > which returns int. Sparse will detect any attempts to return a
> > > > value which is not a VM_FAULT code.
> > > >
> > > > VM_FAULT_SET_HINDEX and VM_FAULT_GET_HINDEX values are changed
> > > > to avoid conflict with other VM_FAULT codes.
> > > >
> > > > Signed-off-by: Souptick Joarder
> > >
> > > For the docs part
> > > Reviewed-by: Mike Rapoport
> > >
> > > > ---
> > > > v2: Updated the change log and corrected the document part.
> > > > name added to the enum that kernel-doc able to parse it.
> > > >
> > > > v3: Corrected the documentation.
> >
> > If no further comment, can we get this patch in queue for 4.21 ?
>
> Do I need to make any further improvement for this patch ?
If no further comment, can we get this patch in queue for 5.0-rcX ?
> >
> > > >
> > > > include/linux/mm.h | 46 --
> > > > include/linux/mm_types.h | 73
> > > > +++-
> > > > 2 files changed, 72 insertions(+), 47 deletions(-)
> > > >
> > > > diff --git a/include/linux/mm.h b/include/linux/mm.h
> > > > index fcf9cc9..511a3ce 100644
> > > > --- a/include/linux/mm.h
> > > > +++ b/include/linux/mm.h
> > > > @@ -1267,52 +1267,6 @@ static inline void clear_page_pfmemalloc(struct
> > > > page *page)
> > > > }
> > > >
> > > > /*
> > > > - * Different kinds of faults, as returned by handle_mm_fault().
> > > > - * Used to decide whether a process gets delivered SIGBUS or
> > > > - * just gets major/minor fault counters bumped up.
> > > > - */
> > > > -
> > > > -#define VM_FAULT_OOM 0x0001
> > > > -#define VM_FAULT_SIGBUS 0x0002
> > > > -#define VM_FAULT_MAJOR 0x0004
> > > > -#define VM_FAULT_WRITE 0x0008 /* Special case for
> > > > get_user_pages */
> > > > -#define VM_FAULT_HWPOISON 0x0010 /* Hit poisoned small page */
> > > > -#define VM_FAULT_HWPOISON_LARGE 0x0020 /* Hit poisoned large page.
> > > > Index encoded in upper bits */
> > > > -#define VM_FAULT_SIGSEGV 0x0040
> > > > -
> > > > -#define VM_FAULT_NOPAGE 0x0100 /* ->fault installed the pte, not
> > > > return page */
> > > > -#define VM_FAULT_LOCKED 0x0200 /* ->fault locked the returned
> > > > page */
> > > > -#define VM_FAULT_RETRY 0x0400 /* ->fault blocked, must retry */
> > > > -#define VM_FAULT_FALLBACK 0x0800 /* huge page fault failed, fall
> > > > back to small */
> > > > -#define VM_FAULT_DONE_COW 0x1000 /* ->fault has fully handled COW
> > > > */
> > > > -#define VM_FAULT_NEEDDSYNC 0x2000 /* ->fault did not modify page
> > > > tables
> > > > - * and needs fsync() to complete
> > > > (for
> > > > - * synchronous page faults in
> > > > DAX) */
> > > > -
> > > > -#define VM_FAULT_ERROR (VM_FAULT_OOM | VM_FAULT_SIGBUS |
> > > > VM_FAULT_SIGSEGV | \
> > > > - VM_FAULT_HWPOISON | VM_FAULT_HWPOISON_LARGE | \
> > > > - VM_FAULT_FALLBACK)
> > > > -
> > > > -#define VM_FAULT_RESULT_TRACE \
> > > > - { VM_FAULT_OOM, "OOM" }, \
> > > > - { VM_FAULT_SIGBUS, "SIGBUS" }, \
> > > > - { VM_FAULT_MAJOR, "MAJOR" }, \
> > > > - { VM_FAULT_WRITE, "WRITE" }, \
> > > > - { VM_FAULT_HWPOISON,"HWPOISON" }, \
> > > > - { VM_FAULT_HWPOISON_LARGE, "HWPOISON_LARGE" }, \
> > > > - { VM_FAULT_SIGSEGV, "SIGSEGV" }, \
> > > > - { VM_FAULT_NOPAGE, "NOPAGE" }, \
> > > > - { VM_FAULT_LOCKED, "LOCKED" }, \
> > > > - { VM_FAULT_RETRY, "RETRY" }, \
> > > > - { VM_FAULT_FALLBACK,"FALLBACK" }, \
> > > > - { VM_FAULT_DONE_COW,"DONE_COW" }, \
> > > > - { VM_FAULT_NEEDDSYNC, "NEEDDSYNC" }
> > > > -
> > > > -/* Encode hstate index for a hwpoisoned large page */
> > > > -#define VM_FAULT_SET_HINDEX(x) ((x) << 12)
> > > > -#define VM_FAULT_GET_HINDEX(x) (((x) >> 12) & 0xf)
> > > > -
> > > > -/*
> > > > * Can be called by the pagefault handler when it gets a VM_FAULT_OOM.
> > > > */
> > > > extern void pagefault_out_of_memory(void);
> > > > diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
> > > > index 5ed8f62..cb25016 100644
> > >
Re: [PATCH v3] mm: Create the new vm_fault_t type
Hi Andrew,
On Sat, Nov 24, 2018 at 10:16 AM Souptick Joarder wrote:
>
> On Thu, Nov 15, 2018 at 7:17 AM Mike Rapoport wrote:
> >
> > On Tue, Nov 06, 2018 at 05:36:42PM +0530, Souptick Joarder wrote:
> > > Page fault handlers are supposed to return VM_FAULT codes,
> > > but some drivers/file systems mistakenly return error
> > > numbers. Now that all drivers/file systems have been converted
> > > to use the vm_fault_t return type, change the type definition
> > > to no longer be compatible with 'int'. By making it an unsigned
> > > int, the function prototype becomes incompatible with a function
> > > which returns int. Sparse will detect any attempts to return a
> > > value which is not a VM_FAULT code.
> > >
> > > VM_FAULT_SET_HINDEX and VM_FAULT_GET_HINDEX values are changed
> > > to avoid conflict with other VM_FAULT codes.
> > >
> > > Signed-off-by: Souptick Joarder
> >
> > For the docs part
> > Reviewed-by: Mike Rapoport
> >
> > > ---
> > > v2: Updated the change log and corrected the document part.
> > > name added to the enum that kernel-doc able to parse it.
> > >
> > > v3: Corrected the documentation.
>
> If no further comment, can we get this patch in queue for 4.21 ?
Do I need to make any further improvement for this patch ?
>
> > >
> > > include/linux/mm.h | 46 --
> > > include/linux/mm_types.h | 73
> > > +++-
> > > 2 files changed, 72 insertions(+), 47 deletions(-)
> > >
> > > diff --git a/include/linux/mm.h b/include/linux/mm.h
> > > index fcf9cc9..511a3ce 100644
> > > --- a/include/linux/mm.h
> > > +++ b/include/linux/mm.h
> > > @@ -1267,52 +1267,6 @@ static inline void clear_page_pfmemalloc(struct
> > > page *page)
> > > }
> > >
> > > /*
> > > - * Different kinds of faults, as returned by handle_mm_fault().
> > > - * Used to decide whether a process gets delivered SIGBUS or
> > > - * just gets major/minor fault counters bumped up.
> > > - */
> > > -
> > > -#define VM_FAULT_OOM 0x0001
> > > -#define VM_FAULT_SIGBUS 0x0002
> > > -#define VM_FAULT_MAJOR 0x0004
> > > -#define VM_FAULT_WRITE 0x0008 /* Special case for get_user_pages
> > > */
> > > -#define VM_FAULT_HWPOISON 0x0010 /* Hit poisoned small page */
> > > -#define VM_FAULT_HWPOISON_LARGE 0x0020 /* Hit poisoned large page.
> > > Index encoded in upper bits */
> > > -#define VM_FAULT_SIGSEGV 0x0040
> > > -
> > > -#define VM_FAULT_NOPAGE 0x0100 /* ->fault installed the pte, not
> > > return page */
> > > -#define VM_FAULT_LOCKED 0x0200 /* ->fault locked the returned page
> > > */
> > > -#define VM_FAULT_RETRY 0x0400 /* ->fault blocked, must retry */
> > > -#define VM_FAULT_FALLBACK 0x0800 /* huge page fault failed, fall
> > > back to small */
> > > -#define VM_FAULT_DONE_COW 0x1000 /* ->fault has fully handled COW */
> > > -#define VM_FAULT_NEEDDSYNC 0x2000 /* ->fault did not modify page
> > > tables
> > > - * and needs fsync() to complete
> > > (for
> > > - * synchronous page faults in DAX)
> > > */
> > > -
> > > -#define VM_FAULT_ERROR (VM_FAULT_OOM | VM_FAULT_SIGBUS |
> > > VM_FAULT_SIGSEGV | \
> > > - VM_FAULT_HWPOISON | VM_FAULT_HWPOISON_LARGE | \
> > > - VM_FAULT_FALLBACK)
> > > -
> > > -#define VM_FAULT_RESULT_TRACE \
> > > - { VM_FAULT_OOM, "OOM" }, \
> > > - { VM_FAULT_SIGBUS, "SIGBUS" }, \
> > > - { VM_FAULT_MAJOR, "MAJOR" }, \
> > > - { VM_FAULT_WRITE, "WRITE" }, \
> > > - { VM_FAULT_HWPOISON,"HWPOISON" }, \
> > > - { VM_FAULT_HWPOISON_LARGE, "HWPOISON_LARGE" }, \
> > > - { VM_FAULT_SIGSEGV, "SIGSEGV" }, \
> > > - { VM_FAULT_NOPAGE, "NOPAGE" }, \
> > > - { VM_FAULT_LOCKED, "LOCKED" }, \
> > > - { VM_FAULT_RETRY, "RETRY" }, \
> > > - { VM_FAULT_FALLBACK,"FALLBACK" }, \
> > > - { VM_FAULT_DONE_COW,"DONE_COW" }, \
> > > - { VM_FAULT_NEEDDSYNC, "NEEDDSYNC" }
> > > -
> > > -/* Encode hstate index for a hwpoisoned large page */
> > > -#define VM_FAULT_SET_HINDEX(x) ((x) << 12)
> > > -#define VM_FAULT_GET_HINDEX(x) (((x) >> 12) & 0xf)
> > > -
> > > -/*
> > > * Can be called by the pagefault handler when it gets a VM_FAULT_OOM.
> > > */
> > > extern void pagefault_out_of_memory(void);
> > > diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
> > > index 5ed8f62..cb25016 100644
> > > --- a/include/linux/mm_types.h
> > > +++ b/include/linux/mm_types.h
> > > @@ -22,7 +22,6 @@
> > > #endif
> > > #define AT_VECTOR_SIZE (2*(AT_VECTOR_SIZE_ARCH + AT_VECTOR_SIZE_BASE +
> > > 1))
> > >
> > > -typedef int vm_fault_t;
> > >
> > > struct address_space;
> > > struct mem_cgroup;
> > > @@ -609,6 +608,78 @@ static inline bool
Re: [PATCH v3] mm: Create the new vm_fault_t type
On Thu, Nov 15, 2018 at 7:17 AM Mike Rapoport wrote:
>
> On Tue, Nov 06, 2018 at 05:36:42PM +0530, Souptick Joarder wrote:
> > Page fault handlers are supposed to return VM_FAULT codes,
> > but some drivers/file systems mistakenly return error
> > numbers. Now that all drivers/file systems have been converted
> > to use the vm_fault_t return type, change the type definition
> > to no longer be compatible with 'int'. By making it an unsigned
> > int, the function prototype becomes incompatible with a function
> > which returns int. Sparse will detect any attempts to return a
> > value which is not a VM_FAULT code.
> >
> > VM_FAULT_SET_HINDEX and VM_FAULT_GET_HINDEX values are changed
> > to avoid conflict with other VM_FAULT codes.
> >
> > Signed-off-by: Souptick Joarder
>
> For the docs part
> Reviewed-by: Mike Rapoport
>
> > ---
> > v2: Updated the change log and corrected the document part.
> > name added to the enum that kernel-doc able to parse it.
> >
> > v3: Corrected the documentation.
If no further comment, can we get this patch in queue for 4.21 ?
> >
> > include/linux/mm.h | 46 --
> > include/linux/mm_types.h | 73
> > +++-
> > 2 files changed, 72 insertions(+), 47 deletions(-)
> >
> > diff --git a/include/linux/mm.h b/include/linux/mm.h
> > index fcf9cc9..511a3ce 100644
> > --- a/include/linux/mm.h
> > +++ b/include/linux/mm.h
> > @@ -1267,52 +1267,6 @@ static inline void clear_page_pfmemalloc(struct page
> > *page)
> > }
> >
> > /*
> > - * Different kinds of faults, as returned by handle_mm_fault().
> > - * Used to decide whether a process gets delivered SIGBUS or
> > - * just gets major/minor fault counters bumped up.
> > - */
> > -
> > -#define VM_FAULT_OOM 0x0001
> > -#define VM_FAULT_SIGBUS 0x0002
> > -#define VM_FAULT_MAJOR 0x0004
> > -#define VM_FAULT_WRITE 0x0008 /* Special case for get_user_pages */
> > -#define VM_FAULT_HWPOISON 0x0010 /* Hit poisoned small page */
> > -#define VM_FAULT_HWPOISON_LARGE 0x0020 /* Hit poisoned large page. Index
> > encoded in upper bits */
> > -#define VM_FAULT_SIGSEGV 0x0040
> > -
> > -#define VM_FAULT_NOPAGE 0x0100 /* ->fault installed the pte, not
> > return page */
> > -#define VM_FAULT_LOCKED 0x0200 /* ->fault locked the returned page */
> > -#define VM_FAULT_RETRY 0x0400 /* ->fault blocked, must retry */
> > -#define VM_FAULT_FALLBACK 0x0800 /* huge page fault failed, fall back
> > to small */
> > -#define VM_FAULT_DONE_COW 0x1000 /* ->fault has fully handled COW */
> > -#define VM_FAULT_NEEDDSYNC 0x2000 /* ->fault did not modify page tables
> > - * and needs fsync() to complete (for
> > - * synchronous page faults in DAX) */
> > -
> > -#define VM_FAULT_ERROR (VM_FAULT_OOM | VM_FAULT_SIGBUS |
> > VM_FAULT_SIGSEGV | \
> > - VM_FAULT_HWPOISON | VM_FAULT_HWPOISON_LARGE | \
> > - VM_FAULT_FALLBACK)
> > -
> > -#define VM_FAULT_RESULT_TRACE \
> > - { VM_FAULT_OOM, "OOM" }, \
> > - { VM_FAULT_SIGBUS, "SIGBUS" }, \
> > - { VM_FAULT_MAJOR, "MAJOR" }, \
> > - { VM_FAULT_WRITE, "WRITE" }, \
> > - { VM_FAULT_HWPOISON,"HWPOISON" }, \
> > - { VM_FAULT_HWPOISON_LARGE, "HWPOISON_LARGE" }, \
> > - { VM_FAULT_SIGSEGV, "SIGSEGV" }, \
> > - { VM_FAULT_NOPAGE, "NOPAGE" }, \
> > - { VM_FAULT_LOCKED, "LOCKED" }, \
> > - { VM_FAULT_RETRY, "RETRY" }, \
> > - { VM_FAULT_FALLBACK,"FALLBACK" }, \
> > - { VM_FAULT_DONE_COW,"DONE_COW" }, \
> > - { VM_FAULT_NEEDDSYNC, "NEEDDSYNC" }
> > -
> > -/* Encode hstate index for a hwpoisoned large page */
> > -#define VM_FAULT_SET_HINDEX(x) ((x) << 12)
> > -#define VM_FAULT_GET_HINDEX(x) (((x) >> 12) & 0xf)
> > -
> > -/*
> > * Can be called by the pagefault handler when it gets a VM_FAULT_OOM.
> > */
> > extern void pagefault_out_of_memory(void);
> > diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
> > index 5ed8f62..cb25016 100644
> > --- a/include/linux/mm_types.h
> > +++ b/include/linux/mm_types.h
> > @@ -22,7 +22,6 @@
> > #endif
> > #define AT_VECTOR_SIZE (2*(AT_VECTOR_SIZE_ARCH + AT_VECTOR_SIZE_BASE + 1))
> >
> > -typedef int vm_fault_t;
> >
> > struct address_space;
> > struct mem_cgroup;
> > @@ -609,6 +608,78 @@ static inline bool mm_tlb_flush_nested(struct
> > mm_struct *mm)
> >
> > struct vm_fault;
> >
> > +/**
> > + * typedef vm_fault_t - Return type for page fault handlers.
> > + *
> > + * Page fault handlers return a bitmask of %VM_FAULT values.
> > + */
> > +typedef __bitwise unsigned int vm_fault_t;
> > +
> > +/**
> > + * enum vm_fault_reason - Page fault handlers return a bitmask of
> > + * these values to tell the core VM
Re: [PATCH v3] mm: Create the new vm_fault_t type
On Thu, Nov 15, 2018 at 7:17 AM Mike Rapoport wrote:
>
> On Tue, Nov 06, 2018 at 05:36:42PM +0530, Souptick Joarder wrote:
> > Page fault handlers are supposed to return VM_FAULT codes,
> > but some drivers/file systems mistakenly return error
> > numbers. Now that all drivers/file systems have been converted
> > to use the vm_fault_t return type, change the type definition
> > to no longer be compatible with 'int'. By making it an unsigned
> > int, the function prototype becomes incompatible with a function
> > which returns int. Sparse will detect any attempts to return a
> > value which is not a VM_FAULT code.
> >
> > VM_FAULT_SET_HINDEX and VM_FAULT_GET_HINDEX values are changed
> > to avoid conflict with other VM_FAULT codes.
> >
> > Signed-off-by: Souptick Joarder
>
> For the docs part
> Reviewed-by: Mike Rapoport
>
> > ---
> > v2: Updated the change log and corrected the document part.
> > name added to the enum that kernel-doc able to parse it.
> >
> > v3: Corrected the documentation.
If no further comment, can we get this patch in queue for 4.21 ?
> >
> > include/linux/mm.h | 46 --
> > include/linux/mm_types.h | 73
> > +++-
> > 2 files changed, 72 insertions(+), 47 deletions(-)
> >
> > diff --git a/include/linux/mm.h b/include/linux/mm.h
> > index fcf9cc9..511a3ce 100644
> > --- a/include/linux/mm.h
> > +++ b/include/linux/mm.h
> > @@ -1267,52 +1267,6 @@ static inline void clear_page_pfmemalloc(struct page
> > *page)
> > }
> >
> > /*
> > - * Different kinds of faults, as returned by handle_mm_fault().
> > - * Used to decide whether a process gets delivered SIGBUS or
> > - * just gets major/minor fault counters bumped up.
> > - */
> > -
> > -#define VM_FAULT_OOM 0x0001
> > -#define VM_FAULT_SIGBUS 0x0002
> > -#define VM_FAULT_MAJOR 0x0004
> > -#define VM_FAULT_WRITE 0x0008 /* Special case for get_user_pages */
> > -#define VM_FAULT_HWPOISON 0x0010 /* Hit poisoned small page */
> > -#define VM_FAULT_HWPOISON_LARGE 0x0020 /* Hit poisoned large page. Index
> > encoded in upper bits */
> > -#define VM_FAULT_SIGSEGV 0x0040
> > -
> > -#define VM_FAULT_NOPAGE 0x0100 /* ->fault installed the pte, not
> > return page */
> > -#define VM_FAULT_LOCKED 0x0200 /* ->fault locked the returned page */
> > -#define VM_FAULT_RETRY 0x0400 /* ->fault blocked, must retry */
> > -#define VM_FAULT_FALLBACK 0x0800 /* huge page fault failed, fall back
> > to small */
> > -#define VM_FAULT_DONE_COW 0x1000 /* ->fault has fully handled COW */
> > -#define VM_FAULT_NEEDDSYNC 0x2000 /* ->fault did not modify page tables
> > - * and needs fsync() to complete (for
> > - * synchronous page faults in DAX) */
> > -
> > -#define VM_FAULT_ERROR (VM_FAULT_OOM | VM_FAULT_SIGBUS |
> > VM_FAULT_SIGSEGV | \
> > - VM_FAULT_HWPOISON | VM_FAULT_HWPOISON_LARGE | \
> > - VM_FAULT_FALLBACK)
> > -
> > -#define VM_FAULT_RESULT_TRACE \
> > - { VM_FAULT_OOM, "OOM" }, \
> > - { VM_FAULT_SIGBUS, "SIGBUS" }, \
> > - { VM_FAULT_MAJOR, "MAJOR" }, \
> > - { VM_FAULT_WRITE, "WRITE" }, \
> > - { VM_FAULT_HWPOISON,"HWPOISON" }, \
> > - { VM_FAULT_HWPOISON_LARGE, "HWPOISON_LARGE" }, \
> > - { VM_FAULT_SIGSEGV, "SIGSEGV" }, \
> > - { VM_FAULT_NOPAGE, "NOPAGE" }, \
> > - { VM_FAULT_LOCKED, "LOCKED" }, \
> > - { VM_FAULT_RETRY, "RETRY" }, \
> > - { VM_FAULT_FALLBACK,"FALLBACK" }, \
> > - { VM_FAULT_DONE_COW,"DONE_COW" }, \
> > - { VM_FAULT_NEEDDSYNC, "NEEDDSYNC" }
> > -
> > -/* Encode hstate index for a hwpoisoned large page */
> > -#define VM_FAULT_SET_HINDEX(x) ((x) << 12)
> > -#define VM_FAULT_GET_HINDEX(x) (((x) >> 12) & 0xf)
> > -
> > -/*
> > * Can be called by the pagefault handler when it gets a VM_FAULT_OOM.
> > */
> > extern void pagefault_out_of_memory(void);
> > diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
> > index 5ed8f62..cb25016 100644
> > --- a/include/linux/mm_types.h
> > +++ b/include/linux/mm_types.h
> > @@ -22,7 +22,6 @@
> > #endif
> > #define AT_VECTOR_SIZE (2*(AT_VECTOR_SIZE_ARCH + AT_VECTOR_SIZE_BASE + 1))
> >
> > -typedef int vm_fault_t;
> >
> > struct address_space;
> > struct mem_cgroup;
> > @@ -609,6 +608,78 @@ static inline bool mm_tlb_flush_nested(struct
> > mm_struct *mm)
> >
> > struct vm_fault;
> >
> > +/**
> > + * typedef vm_fault_t - Return type for page fault handlers.
> > + *
> > + * Page fault handlers return a bitmask of %VM_FAULT values.
> > + */
> > +typedef __bitwise unsigned int vm_fault_t;
> > +
> > +/**
> > + * enum vm_fault_reason - Page fault handlers return a bitmask of
> > + * these values to tell the core VM
Re: [PATCH v3] mm: Create the new vm_fault_t type
On Tue, Nov 06, 2018 at 05:36:42PM +0530, Souptick Joarder wrote:
> Page fault handlers are supposed to return VM_FAULT codes,
> but some drivers/file systems mistakenly return error
> numbers. Now that all drivers/file systems have been converted
> to use the vm_fault_t return type, change the type definition
> to no longer be compatible with 'int'. By making it an unsigned
> int, the function prototype becomes incompatible with a function
> which returns int. Sparse will detect any attempts to return a
> value which is not a VM_FAULT code.
>
> VM_FAULT_SET_HINDEX and VM_FAULT_GET_HINDEX values are changed
> to avoid conflict with other VM_FAULT codes.
>
> Signed-off-by: Souptick Joarder
For the docs part
Reviewed-by: Mike Rapoport
> ---
> v2: Updated the change log and corrected the document part.
> name added to the enum that kernel-doc able to parse it.
>
> v3: Corrected the documentation.
>
> include/linux/mm.h | 46 --
> include/linux/mm_types.h | 73
> +++-
> 2 files changed, 72 insertions(+), 47 deletions(-)
>
> diff --git a/include/linux/mm.h b/include/linux/mm.h
> index fcf9cc9..511a3ce 100644
> --- a/include/linux/mm.h
> +++ b/include/linux/mm.h
> @@ -1267,52 +1267,6 @@ static inline void clear_page_pfmemalloc(struct page
> *page)
> }
>
> /*
> - * Different kinds of faults, as returned by handle_mm_fault().
> - * Used to decide whether a process gets delivered SIGBUS or
> - * just gets major/minor fault counters bumped up.
> - */
> -
> -#define VM_FAULT_OOM 0x0001
> -#define VM_FAULT_SIGBUS 0x0002
> -#define VM_FAULT_MAJOR 0x0004
> -#define VM_FAULT_WRITE 0x0008 /* Special case for get_user_pages */
> -#define VM_FAULT_HWPOISON 0x0010 /* Hit poisoned small page */
> -#define VM_FAULT_HWPOISON_LARGE 0x0020 /* Hit poisoned large page. Index
> encoded in upper bits */
> -#define VM_FAULT_SIGSEGV 0x0040
> -
> -#define VM_FAULT_NOPAGE 0x0100 /* ->fault installed the pte, not
> return page */
> -#define VM_FAULT_LOCKED 0x0200 /* ->fault locked the returned page */
> -#define VM_FAULT_RETRY 0x0400 /* ->fault blocked, must retry */
> -#define VM_FAULT_FALLBACK 0x0800 /* huge page fault failed, fall back to
> small */
> -#define VM_FAULT_DONE_COW 0x1000 /* ->fault has fully handled COW */
> -#define VM_FAULT_NEEDDSYNC 0x2000 /* ->fault did not modify page tables
> - * and needs fsync() to complete (for
> - * synchronous page faults in DAX) */
> -
> -#define VM_FAULT_ERROR (VM_FAULT_OOM | VM_FAULT_SIGBUS |
> VM_FAULT_SIGSEGV | \
> - VM_FAULT_HWPOISON | VM_FAULT_HWPOISON_LARGE | \
> - VM_FAULT_FALLBACK)
> -
> -#define VM_FAULT_RESULT_TRACE \
> - { VM_FAULT_OOM, "OOM" }, \
> - { VM_FAULT_SIGBUS, "SIGBUS" }, \
> - { VM_FAULT_MAJOR, "MAJOR" }, \
> - { VM_FAULT_WRITE, "WRITE" }, \
> - { VM_FAULT_HWPOISON,"HWPOISON" }, \
> - { VM_FAULT_HWPOISON_LARGE, "HWPOISON_LARGE" }, \
> - { VM_FAULT_SIGSEGV, "SIGSEGV" }, \
> - { VM_FAULT_NOPAGE, "NOPAGE" }, \
> - { VM_FAULT_LOCKED, "LOCKED" }, \
> - { VM_FAULT_RETRY, "RETRY" }, \
> - { VM_FAULT_FALLBACK,"FALLBACK" }, \
> - { VM_FAULT_DONE_COW,"DONE_COW" }, \
> - { VM_FAULT_NEEDDSYNC, "NEEDDSYNC" }
> -
> -/* Encode hstate index for a hwpoisoned large page */
> -#define VM_FAULT_SET_HINDEX(x) ((x) << 12)
> -#define VM_FAULT_GET_HINDEX(x) (((x) >> 12) & 0xf)
> -
> -/*
> * Can be called by the pagefault handler when it gets a VM_FAULT_OOM.
> */
> extern void pagefault_out_of_memory(void);
> diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
> index 5ed8f62..cb25016 100644
> --- a/include/linux/mm_types.h
> +++ b/include/linux/mm_types.h
> @@ -22,7 +22,6 @@
> #endif
> #define AT_VECTOR_SIZE (2*(AT_VECTOR_SIZE_ARCH + AT_VECTOR_SIZE_BASE + 1))
>
> -typedef int vm_fault_t;
>
> struct address_space;
> struct mem_cgroup;
> @@ -609,6 +608,78 @@ static inline bool mm_tlb_flush_nested(struct mm_struct
> *mm)
>
> struct vm_fault;
>
> +/**
> + * typedef vm_fault_t - Return type for page fault handlers.
> + *
> + * Page fault handlers return a bitmask of %VM_FAULT values.
> + */
> +typedef __bitwise unsigned int vm_fault_t;
> +
> +/**
> + * enum vm_fault_reason - Page fault handlers return a bitmask of
> + * these values to tell the core VM what happened when handling the
> + * fault. Used to decide whether a process gets delivered SIGBUS or
> + * just gets major/minor fault counters bumped up.
> + *
> + * @VM_FAULT_OOM:Out Of Memory
> + * @VM_FAULT_SIGBUS: Bad access
> + * @VM_FAULT_MAJOR: Page read from storage
> + * @VM_FAULT_WRITE:
Re: [PATCH v3] mm: Create the new vm_fault_t type
On Tue, Nov 06, 2018 at 05:36:42PM +0530, Souptick Joarder wrote:
> Page fault handlers are supposed to return VM_FAULT codes,
> but some drivers/file systems mistakenly return error
> numbers. Now that all drivers/file systems have been converted
> to use the vm_fault_t return type, change the type definition
> to no longer be compatible with 'int'. By making it an unsigned
> int, the function prototype becomes incompatible with a function
> which returns int. Sparse will detect any attempts to return a
> value which is not a VM_FAULT code.
>
> VM_FAULT_SET_HINDEX and VM_FAULT_GET_HINDEX values are changed
> to avoid conflict with other VM_FAULT codes.
>
> Signed-off-by: Souptick Joarder
For the docs part
Reviewed-by: Mike Rapoport
> ---
> v2: Updated the change log and corrected the document part.
> name added to the enum that kernel-doc able to parse it.
>
> v3: Corrected the documentation.
>
> include/linux/mm.h | 46 --
> include/linux/mm_types.h | 73
> +++-
> 2 files changed, 72 insertions(+), 47 deletions(-)
>
> diff --git a/include/linux/mm.h b/include/linux/mm.h
> index fcf9cc9..511a3ce 100644
> --- a/include/linux/mm.h
> +++ b/include/linux/mm.h
> @@ -1267,52 +1267,6 @@ static inline void clear_page_pfmemalloc(struct page
> *page)
> }
>
> /*
> - * Different kinds of faults, as returned by handle_mm_fault().
> - * Used to decide whether a process gets delivered SIGBUS or
> - * just gets major/minor fault counters bumped up.
> - */
> -
> -#define VM_FAULT_OOM 0x0001
> -#define VM_FAULT_SIGBUS 0x0002
> -#define VM_FAULT_MAJOR 0x0004
> -#define VM_FAULT_WRITE 0x0008 /* Special case for get_user_pages */
> -#define VM_FAULT_HWPOISON 0x0010 /* Hit poisoned small page */
> -#define VM_FAULT_HWPOISON_LARGE 0x0020 /* Hit poisoned large page. Index
> encoded in upper bits */
> -#define VM_FAULT_SIGSEGV 0x0040
> -
> -#define VM_FAULT_NOPAGE 0x0100 /* ->fault installed the pte, not
> return page */
> -#define VM_FAULT_LOCKED 0x0200 /* ->fault locked the returned page */
> -#define VM_FAULT_RETRY 0x0400 /* ->fault blocked, must retry */
> -#define VM_FAULT_FALLBACK 0x0800 /* huge page fault failed, fall back to
> small */
> -#define VM_FAULT_DONE_COW 0x1000 /* ->fault has fully handled COW */
> -#define VM_FAULT_NEEDDSYNC 0x2000 /* ->fault did not modify page tables
> - * and needs fsync() to complete (for
> - * synchronous page faults in DAX) */
> -
> -#define VM_FAULT_ERROR (VM_FAULT_OOM | VM_FAULT_SIGBUS |
> VM_FAULT_SIGSEGV | \
> - VM_FAULT_HWPOISON | VM_FAULT_HWPOISON_LARGE | \
> - VM_FAULT_FALLBACK)
> -
> -#define VM_FAULT_RESULT_TRACE \
> - { VM_FAULT_OOM, "OOM" }, \
> - { VM_FAULT_SIGBUS, "SIGBUS" }, \
> - { VM_FAULT_MAJOR, "MAJOR" }, \
> - { VM_FAULT_WRITE, "WRITE" }, \
> - { VM_FAULT_HWPOISON,"HWPOISON" }, \
> - { VM_FAULT_HWPOISON_LARGE, "HWPOISON_LARGE" }, \
> - { VM_FAULT_SIGSEGV, "SIGSEGV" }, \
> - { VM_FAULT_NOPAGE, "NOPAGE" }, \
> - { VM_FAULT_LOCKED, "LOCKED" }, \
> - { VM_FAULT_RETRY, "RETRY" }, \
> - { VM_FAULT_FALLBACK,"FALLBACK" }, \
> - { VM_FAULT_DONE_COW,"DONE_COW" }, \
> - { VM_FAULT_NEEDDSYNC, "NEEDDSYNC" }
> -
> -/* Encode hstate index for a hwpoisoned large page */
> -#define VM_FAULT_SET_HINDEX(x) ((x) << 12)
> -#define VM_FAULT_GET_HINDEX(x) (((x) >> 12) & 0xf)
> -
> -/*
> * Can be called by the pagefault handler when it gets a VM_FAULT_OOM.
> */
> extern void pagefault_out_of_memory(void);
> diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
> index 5ed8f62..cb25016 100644
> --- a/include/linux/mm_types.h
> +++ b/include/linux/mm_types.h
> @@ -22,7 +22,6 @@
> #endif
> #define AT_VECTOR_SIZE (2*(AT_VECTOR_SIZE_ARCH + AT_VECTOR_SIZE_BASE + 1))
>
> -typedef int vm_fault_t;
>
> struct address_space;
> struct mem_cgroup;
> @@ -609,6 +608,78 @@ static inline bool mm_tlb_flush_nested(struct mm_struct
> *mm)
>
> struct vm_fault;
>
> +/**
> + * typedef vm_fault_t - Return type for page fault handlers.
> + *
> + * Page fault handlers return a bitmask of %VM_FAULT values.
> + */
> +typedef __bitwise unsigned int vm_fault_t;
> +
> +/**
> + * enum vm_fault_reason - Page fault handlers return a bitmask of
> + * these values to tell the core VM what happened when handling the
> + * fault. Used to decide whether a process gets delivered SIGBUS or
> + * just gets major/minor fault counters bumped up.
> + *
> + * @VM_FAULT_OOM:Out Of Memory
> + * @VM_FAULT_SIGBUS: Bad access
> + * @VM_FAULT_MAJOR: Page read from storage
> + * @VM_FAULT_WRITE:
Re: [PATCH v3] mm: Create the new vm_fault_t type
> On Nov 13, 2018, at 10:13 PM, Souptick Joarder wrote: > > On Tue, Nov 6, 2018 at 5:33 PM Souptick Joarder wrote: >> >> Page fault handlers are supposed to return VM_FAULT codes, >> but some drivers/file systems mistakenly return error >> numbers. Now that all drivers/file systems have been converted >> to use the vm_fault_t return type, change the type definition >> to no longer be compatible with 'int'. By making it an unsigned >> int, the function prototype becomes incompatible with a function >> which returns int. Sparse will detect any attempts to return a >> value which is not a VM_FAULT code. >> >> VM_FAULT_SET_HINDEX and VM_FAULT_GET_HINDEX values are changed >> to avoid conflict with other VM_FAULT codes. >> >> Signed-off-by: Souptick Joarder > > Any further comment on this patch ? Reviewed-by: William Kucharski
Re: [PATCH v3] mm: Create the new vm_fault_t type
> On Nov 13, 2018, at 10:13 PM, Souptick Joarder wrote: > > On Tue, Nov 6, 2018 at 5:33 PM Souptick Joarder wrote: >> >> Page fault handlers are supposed to return VM_FAULT codes, >> but some drivers/file systems mistakenly return error >> numbers. Now that all drivers/file systems have been converted >> to use the vm_fault_t return type, change the type definition >> to no longer be compatible with 'int'. By making it an unsigned >> int, the function prototype becomes incompatible with a function >> which returns int. Sparse will detect any attempts to return a >> value which is not a VM_FAULT code. >> >> VM_FAULT_SET_HINDEX and VM_FAULT_GET_HINDEX values are changed >> to avoid conflict with other VM_FAULT codes. >> >> Signed-off-by: Souptick Joarder > > Any further comment on this patch ? Reviewed-by: William Kucharski
Re: [PATCH v3] mm: Create the new vm_fault_t type
On Tue, Nov 6, 2018 at 5:33 PM Souptick Joarder wrote:
>
> Page fault handlers are supposed to return VM_FAULT codes,
> but some drivers/file systems mistakenly return error
> numbers. Now that all drivers/file systems have been converted
> to use the vm_fault_t return type, change the type definition
> to no longer be compatible with 'int'. By making it an unsigned
> int, the function prototype becomes incompatible with a function
> which returns int. Sparse will detect any attempts to return a
> value which is not a VM_FAULT code.
>
> VM_FAULT_SET_HINDEX and VM_FAULT_GET_HINDEX values are changed
> to avoid conflict with other VM_FAULT codes.
>
> Signed-off-by: Souptick Joarder
Any further comment on this patch ?
> ---
> v2: Updated the change log and corrected the document part.
> name added to the enum that kernel-doc able to parse it.
>
> v3: Corrected the documentation.
>
> include/linux/mm.h | 46 --
> include/linux/mm_types.h | 73
> +++-
> 2 files changed, 72 insertions(+), 47 deletions(-)
>
> diff --git a/include/linux/mm.h b/include/linux/mm.h
> index fcf9cc9..511a3ce 100644
> --- a/include/linux/mm.h
> +++ b/include/linux/mm.h
> @@ -1267,52 +1267,6 @@ static inline void clear_page_pfmemalloc(struct page
> *page)
> }
>
> /*
> - * Different kinds of faults, as returned by handle_mm_fault().
> - * Used to decide whether a process gets delivered SIGBUS or
> - * just gets major/minor fault counters bumped up.
> - */
> -
> -#define VM_FAULT_OOM 0x0001
> -#define VM_FAULT_SIGBUS0x0002
> -#define VM_FAULT_MAJOR 0x0004
> -#define VM_FAULT_WRITE 0x0008 /* Special case for get_user_pages */
> -#define VM_FAULT_HWPOISON 0x0010 /* Hit poisoned small page */
> -#define VM_FAULT_HWPOISON_LARGE 0x0020 /* Hit poisoned large page. Index
> encoded in upper bits */
> -#define VM_FAULT_SIGSEGV 0x0040
> -
> -#define VM_FAULT_NOPAGE0x0100 /* ->fault installed the pte, not
> return page */
> -#define VM_FAULT_LOCKED0x0200 /* ->fault locked the returned page */
> -#define VM_FAULT_RETRY 0x0400 /* ->fault blocked, must retry */
> -#define VM_FAULT_FALLBACK 0x0800 /* huge page fault failed, fall back
> to small */
> -#define VM_FAULT_DONE_COW 0x1000 /* ->fault has fully handled COW */
> -#define VM_FAULT_NEEDDSYNC 0x2000 /* ->fault did not modify page tables
> -* and needs fsync() to complete (for
> -* synchronous page faults in DAX) */
> -
> -#define VM_FAULT_ERROR (VM_FAULT_OOM | VM_FAULT_SIGBUS | VM_FAULT_SIGSEGV | \
> -VM_FAULT_HWPOISON | VM_FAULT_HWPOISON_LARGE | \
> -VM_FAULT_FALLBACK)
> -
> -#define VM_FAULT_RESULT_TRACE \
> - { VM_FAULT_OOM, "OOM" }, \
> - { VM_FAULT_SIGBUS, "SIGBUS" }, \
> - { VM_FAULT_MAJOR, "MAJOR" }, \
> - { VM_FAULT_WRITE, "WRITE" }, \
> - { VM_FAULT_HWPOISON,"HWPOISON" }, \
> - { VM_FAULT_HWPOISON_LARGE, "HWPOISON_LARGE" }, \
> - { VM_FAULT_SIGSEGV, "SIGSEGV" }, \
> - { VM_FAULT_NOPAGE, "NOPAGE" }, \
> - { VM_FAULT_LOCKED, "LOCKED" }, \
> - { VM_FAULT_RETRY, "RETRY" }, \
> - { VM_FAULT_FALLBACK,"FALLBACK" }, \
> - { VM_FAULT_DONE_COW,"DONE_COW" }, \
> - { VM_FAULT_NEEDDSYNC, "NEEDDSYNC" }
> -
> -/* Encode hstate index for a hwpoisoned large page */
> -#define VM_FAULT_SET_HINDEX(x) ((x) << 12)
> -#define VM_FAULT_GET_HINDEX(x) (((x) >> 12) & 0xf)
> -
> -/*
> * Can be called by the pagefault handler when it gets a VM_FAULT_OOM.
> */
> extern void pagefault_out_of_memory(void);
> diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
> index 5ed8f62..cb25016 100644
> --- a/include/linux/mm_types.h
> +++ b/include/linux/mm_types.h
> @@ -22,7 +22,6 @@
> #endif
> #define AT_VECTOR_SIZE (2*(AT_VECTOR_SIZE_ARCH + AT_VECTOR_SIZE_BASE + 1))
>
> -typedef int vm_fault_t;
>
> struct address_space;
> struct mem_cgroup;
> @@ -609,6 +608,78 @@ static inline bool mm_tlb_flush_nested(struct mm_struct
> *mm)
>
> struct vm_fault;
>
> +/**
> + * typedef vm_fault_t - Return type for page fault handlers.
> + *
> + * Page fault handlers return a bitmask of %VM_FAULT values.
> + */
> +typedef __bitwise unsigned int vm_fault_t;
> +
> +/**
> + * enum vm_fault_reason - Page fault handlers return a bitmask of
> + * these values to tell the core VM what happened when handling the
> + * fault. Used to decide whether a process gets delivered SIGBUS or
> + * just gets major/minor fault counters bumped up.
> + *
> + * @VM_FAULT_OOM: Out Of Memory
> + * @VM_FAULT_SIGBUS: Bad access
> + * @VM_FAULT_MAJOR:Page read from storage
> + * @VM_FAULT_WRITE:
Re: [PATCH v3] mm: Create the new vm_fault_t type
On Tue, Nov 6, 2018 at 5:33 PM Souptick Joarder wrote:
>
> Page fault handlers are supposed to return VM_FAULT codes,
> but some drivers/file systems mistakenly return error
> numbers. Now that all drivers/file systems have been converted
> to use the vm_fault_t return type, change the type definition
> to no longer be compatible with 'int'. By making it an unsigned
> int, the function prototype becomes incompatible with a function
> which returns int. Sparse will detect any attempts to return a
> value which is not a VM_FAULT code.
>
> VM_FAULT_SET_HINDEX and VM_FAULT_GET_HINDEX values are changed
> to avoid conflict with other VM_FAULT codes.
>
> Signed-off-by: Souptick Joarder
Any further comment on this patch ?
> ---
> v2: Updated the change log and corrected the document part.
> name added to the enum that kernel-doc able to parse it.
>
> v3: Corrected the documentation.
>
> include/linux/mm.h | 46 --
> include/linux/mm_types.h | 73
> +++-
> 2 files changed, 72 insertions(+), 47 deletions(-)
>
> diff --git a/include/linux/mm.h b/include/linux/mm.h
> index fcf9cc9..511a3ce 100644
> --- a/include/linux/mm.h
> +++ b/include/linux/mm.h
> @@ -1267,52 +1267,6 @@ static inline void clear_page_pfmemalloc(struct page
> *page)
> }
>
> /*
> - * Different kinds of faults, as returned by handle_mm_fault().
> - * Used to decide whether a process gets delivered SIGBUS or
> - * just gets major/minor fault counters bumped up.
> - */
> -
> -#define VM_FAULT_OOM 0x0001
> -#define VM_FAULT_SIGBUS0x0002
> -#define VM_FAULT_MAJOR 0x0004
> -#define VM_FAULT_WRITE 0x0008 /* Special case for get_user_pages */
> -#define VM_FAULT_HWPOISON 0x0010 /* Hit poisoned small page */
> -#define VM_FAULT_HWPOISON_LARGE 0x0020 /* Hit poisoned large page. Index
> encoded in upper bits */
> -#define VM_FAULT_SIGSEGV 0x0040
> -
> -#define VM_FAULT_NOPAGE0x0100 /* ->fault installed the pte, not
> return page */
> -#define VM_FAULT_LOCKED0x0200 /* ->fault locked the returned page */
> -#define VM_FAULT_RETRY 0x0400 /* ->fault blocked, must retry */
> -#define VM_FAULT_FALLBACK 0x0800 /* huge page fault failed, fall back
> to small */
> -#define VM_FAULT_DONE_COW 0x1000 /* ->fault has fully handled COW */
> -#define VM_FAULT_NEEDDSYNC 0x2000 /* ->fault did not modify page tables
> -* and needs fsync() to complete (for
> -* synchronous page faults in DAX) */
> -
> -#define VM_FAULT_ERROR (VM_FAULT_OOM | VM_FAULT_SIGBUS | VM_FAULT_SIGSEGV | \
> -VM_FAULT_HWPOISON | VM_FAULT_HWPOISON_LARGE | \
> -VM_FAULT_FALLBACK)
> -
> -#define VM_FAULT_RESULT_TRACE \
> - { VM_FAULT_OOM, "OOM" }, \
> - { VM_FAULT_SIGBUS, "SIGBUS" }, \
> - { VM_FAULT_MAJOR, "MAJOR" }, \
> - { VM_FAULT_WRITE, "WRITE" }, \
> - { VM_FAULT_HWPOISON,"HWPOISON" }, \
> - { VM_FAULT_HWPOISON_LARGE, "HWPOISON_LARGE" }, \
> - { VM_FAULT_SIGSEGV, "SIGSEGV" }, \
> - { VM_FAULT_NOPAGE, "NOPAGE" }, \
> - { VM_FAULT_LOCKED, "LOCKED" }, \
> - { VM_FAULT_RETRY, "RETRY" }, \
> - { VM_FAULT_FALLBACK,"FALLBACK" }, \
> - { VM_FAULT_DONE_COW,"DONE_COW" }, \
> - { VM_FAULT_NEEDDSYNC, "NEEDDSYNC" }
> -
> -/* Encode hstate index for a hwpoisoned large page */
> -#define VM_FAULT_SET_HINDEX(x) ((x) << 12)
> -#define VM_FAULT_GET_HINDEX(x) (((x) >> 12) & 0xf)
> -
> -/*
> * Can be called by the pagefault handler when it gets a VM_FAULT_OOM.
> */
> extern void pagefault_out_of_memory(void);
> diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
> index 5ed8f62..cb25016 100644
> --- a/include/linux/mm_types.h
> +++ b/include/linux/mm_types.h
> @@ -22,7 +22,6 @@
> #endif
> #define AT_VECTOR_SIZE (2*(AT_VECTOR_SIZE_ARCH + AT_VECTOR_SIZE_BASE + 1))
>
> -typedef int vm_fault_t;
>
> struct address_space;
> struct mem_cgroup;
> @@ -609,6 +608,78 @@ static inline bool mm_tlb_flush_nested(struct mm_struct
> *mm)
>
> struct vm_fault;
>
> +/**
> + * typedef vm_fault_t - Return type for page fault handlers.
> + *
> + * Page fault handlers return a bitmask of %VM_FAULT values.
> + */
> +typedef __bitwise unsigned int vm_fault_t;
> +
> +/**
> + * enum vm_fault_reason - Page fault handlers return a bitmask of
> + * these values to tell the core VM what happened when handling the
> + * fault. Used to decide whether a process gets delivered SIGBUS or
> + * just gets major/minor fault counters bumped up.
> + *
> + * @VM_FAULT_OOM: Out Of Memory
> + * @VM_FAULT_SIGBUS: Bad access
> + * @VM_FAULT_MAJOR:Page read from storage
> + * @VM_FAULT_WRITE:
Re: [PATCH v3] mm: Create the new vm_fault_t type
[off-list] Please do not submit a new version of the patch just after a minor feedback to the documentation. Wait for some more feedback. Sending 3 versions in about 2 days is just way too much. Thanks! -- Michal Hocko SUSE Labs
Re: [PATCH v3] mm: Create the new vm_fault_t type
[off-list] Please do not submit a new version of the patch just after a minor feedback to the documentation. Wait for some more feedback. Sending 3 versions in about 2 days is just way too much. Thanks! -- Michal Hocko SUSE Labs
[PATCH v3] mm: Create the new vm_fault_t type
Page fault handlers are supposed to return VM_FAULT codes,
but some drivers/file systems mistakenly return error
numbers. Now that all drivers/file systems have been converted
to use the vm_fault_t return type, change the type definition
to no longer be compatible with 'int'. By making it an unsigned
int, the function prototype becomes incompatible with a function
which returns int. Sparse will detect any attempts to return a
value which is not a VM_FAULT code.
VM_FAULT_SET_HINDEX and VM_FAULT_GET_HINDEX values are changed
to avoid conflict with other VM_FAULT codes.
Signed-off-by: Souptick Joarder
---
v2: Updated the change log and corrected the document part.
name added to the enum that kernel-doc able to parse it.
v3: Corrected the documentation.
include/linux/mm.h | 46 --
include/linux/mm_types.h | 73 +++-
2 files changed, 72 insertions(+), 47 deletions(-)
diff --git a/include/linux/mm.h b/include/linux/mm.h
index fcf9cc9..511a3ce 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1267,52 +1267,6 @@ static inline void clear_page_pfmemalloc(struct page
*page)
}
/*
- * Different kinds of faults, as returned by handle_mm_fault().
- * Used to decide whether a process gets delivered SIGBUS or
- * just gets major/minor fault counters bumped up.
- */
-
-#define VM_FAULT_OOM 0x0001
-#define VM_FAULT_SIGBUS0x0002
-#define VM_FAULT_MAJOR 0x0004
-#define VM_FAULT_WRITE 0x0008 /* Special case for get_user_pages */
-#define VM_FAULT_HWPOISON 0x0010 /* Hit poisoned small page */
-#define VM_FAULT_HWPOISON_LARGE 0x0020 /* Hit poisoned large page. Index
encoded in upper bits */
-#define VM_FAULT_SIGSEGV 0x0040
-
-#define VM_FAULT_NOPAGE0x0100 /* ->fault installed the pte, not
return page */
-#define VM_FAULT_LOCKED0x0200 /* ->fault locked the returned page */
-#define VM_FAULT_RETRY 0x0400 /* ->fault blocked, must retry */
-#define VM_FAULT_FALLBACK 0x0800 /* huge page fault failed, fall back to
small */
-#define VM_FAULT_DONE_COW 0x1000 /* ->fault has fully handled COW */
-#define VM_FAULT_NEEDDSYNC 0x2000 /* ->fault did not modify page tables
-* and needs fsync() to complete (for
-* synchronous page faults in DAX) */
-
-#define VM_FAULT_ERROR (VM_FAULT_OOM | VM_FAULT_SIGBUS | VM_FAULT_SIGSEGV | \
-VM_FAULT_HWPOISON | VM_FAULT_HWPOISON_LARGE | \
-VM_FAULT_FALLBACK)
-
-#define VM_FAULT_RESULT_TRACE \
- { VM_FAULT_OOM, "OOM" }, \
- { VM_FAULT_SIGBUS, "SIGBUS" }, \
- { VM_FAULT_MAJOR, "MAJOR" }, \
- { VM_FAULT_WRITE, "WRITE" }, \
- { VM_FAULT_HWPOISON,"HWPOISON" }, \
- { VM_FAULT_HWPOISON_LARGE, "HWPOISON_LARGE" }, \
- { VM_FAULT_SIGSEGV, "SIGSEGV" }, \
- { VM_FAULT_NOPAGE, "NOPAGE" }, \
- { VM_FAULT_LOCKED, "LOCKED" }, \
- { VM_FAULT_RETRY, "RETRY" }, \
- { VM_FAULT_FALLBACK,"FALLBACK" }, \
- { VM_FAULT_DONE_COW,"DONE_COW" }, \
- { VM_FAULT_NEEDDSYNC, "NEEDDSYNC" }
-
-/* Encode hstate index for a hwpoisoned large page */
-#define VM_FAULT_SET_HINDEX(x) ((x) << 12)
-#define VM_FAULT_GET_HINDEX(x) (((x) >> 12) & 0xf)
-
-/*
* Can be called by the pagefault handler when it gets a VM_FAULT_OOM.
*/
extern void pagefault_out_of_memory(void);
diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index 5ed8f62..cb25016 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -22,7 +22,6 @@
#endif
#define AT_VECTOR_SIZE (2*(AT_VECTOR_SIZE_ARCH + AT_VECTOR_SIZE_BASE + 1))
-typedef int vm_fault_t;
struct address_space;
struct mem_cgroup;
@@ -609,6 +608,78 @@ static inline bool mm_tlb_flush_nested(struct mm_struct
*mm)
struct vm_fault;
+/**
+ * typedef vm_fault_t - Return type for page fault handlers.
+ *
+ * Page fault handlers return a bitmask of %VM_FAULT values.
+ */
+typedef __bitwise unsigned int vm_fault_t;
+
+/**
+ * enum vm_fault_reason - Page fault handlers return a bitmask of
+ * these values to tell the core VM what happened when handling the
+ * fault. Used to decide whether a process gets delivered SIGBUS or
+ * just gets major/minor fault counters bumped up.
+ *
+ * @VM_FAULT_OOM: Out Of Memory
+ * @VM_FAULT_SIGBUS: Bad access
+ * @VM_FAULT_MAJOR:Page read from storage
+ * @VM_FAULT_WRITE:Special case for get_user_pages
+ * @VM_FAULT_HWPOISON: Hit poisoned small page
+ * @VM_FAULT_HWPOISON_LARGE: Hit poisoned large page. Index encoded
+ * in upper bits
+ * @VM_FAULT_SIGSEGV: segmentation fault
+ * @VM_FAULT_NOPAGE: ->fault installed the pte, not
[PATCH v3] mm: Create the new vm_fault_t type
Page fault handlers are supposed to return VM_FAULT codes,
but some drivers/file systems mistakenly return error
numbers. Now that all drivers/file systems have been converted
to use the vm_fault_t return type, change the type definition
to no longer be compatible with 'int'. By making it an unsigned
int, the function prototype becomes incompatible with a function
which returns int. Sparse will detect any attempts to return a
value which is not a VM_FAULT code.
VM_FAULT_SET_HINDEX and VM_FAULT_GET_HINDEX values are changed
to avoid conflict with other VM_FAULT codes.
Signed-off-by: Souptick Joarder
---
v2: Updated the change log and corrected the document part.
name added to the enum that kernel-doc able to parse it.
v3: Corrected the documentation.
include/linux/mm.h | 46 --
include/linux/mm_types.h | 73 +++-
2 files changed, 72 insertions(+), 47 deletions(-)
diff --git a/include/linux/mm.h b/include/linux/mm.h
index fcf9cc9..511a3ce 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1267,52 +1267,6 @@ static inline void clear_page_pfmemalloc(struct page
*page)
}
/*
- * Different kinds of faults, as returned by handle_mm_fault().
- * Used to decide whether a process gets delivered SIGBUS or
- * just gets major/minor fault counters bumped up.
- */
-
-#define VM_FAULT_OOM 0x0001
-#define VM_FAULT_SIGBUS0x0002
-#define VM_FAULT_MAJOR 0x0004
-#define VM_FAULT_WRITE 0x0008 /* Special case for get_user_pages */
-#define VM_FAULT_HWPOISON 0x0010 /* Hit poisoned small page */
-#define VM_FAULT_HWPOISON_LARGE 0x0020 /* Hit poisoned large page. Index
encoded in upper bits */
-#define VM_FAULT_SIGSEGV 0x0040
-
-#define VM_FAULT_NOPAGE0x0100 /* ->fault installed the pte, not
return page */
-#define VM_FAULT_LOCKED0x0200 /* ->fault locked the returned page */
-#define VM_FAULT_RETRY 0x0400 /* ->fault blocked, must retry */
-#define VM_FAULT_FALLBACK 0x0800 /* huge page fault failed, fall back to
small */
-#define VM_FAULT_DONE_COW 0x1000 /* ->fault has fully handled COW */
-#define VM_FAULT_NEEDDSYNC 0x2000 /* ->fault did not modify page tables
-* and needs fsync() to complete (for
-* synchronous page faults in DAX) */
-
-#define VM_FAULT_ERROR (VM_FAULT_OOM | VM_FAULT_SIGBUS | VM_FAULT_SIGSEGV | \
-VM_FAULT_HWPOISON | VM_FAULT_HWPOISON_LARGE | \
-VM_FAULT_FALLBACK)
-
-#define VM_FAULT_RESULT_TRACE \
- { VM_FAULT_OOM, "OOM" }, \
- { VM_FAULT_SIGBUS, "SIGBUS" }, \
- { VM_FAULT_MAJOR, "MAJOR" }, \
- { VM_FAULT_WRITE, "WRITE" }, \
- { VM_FAULT_HWPOISON,"HWPOISON" }, \
- { VM_FAULT_HWPOISON_LARGE, "HWPOISON_LARGE" }, \
- { VM_FAULT_SIGSEGV, "SIGSEGV" }, \
- { VM_FAULT_NOPAGE, "NOPAGE" }, \
- { VM_FAULT_LOCKED, "LOCKED" }, \
- { VM_FAULT_RETRY, "RETRY" }, \
- { VM_FAULT_FALLBACK,"FALLBACK" }, \
- { VM_FAULT_DONE_COW,"DONE_COW" }, \
- { VM_FAULT_NEEDDSYNC, "NEEDDSYNC" }
-
-/* Encode hstate index for a hwpoisoned large page */
-#define VM_FAULT_SET_HINDEX(x) ((x) << 12)
-#define VM_FAULT_GET_HINDEX(x) (((x) >> 12) & 0xf)
-
-/*
* Can be called by the pagefault handler when it gets a VM_FAULT_OOM.
*/
extern void pagefault_out_of_memory(void);
diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index 5ed8f62..cb25016 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -22,7 +22,6 @@
#endif
#define AT_VECTOR_SIZE (2*(AT_VECTOR_SIZE_ARCH + AT_VECTOR_SIZE_BASE + 1))
-typedef int vm_fault_t;
struct address_space;
struct mem_cgroup;
@@ -609,6 +608,78 @@ static inline bool mm_tlb_flush_nested(struct mm_struct
*mm)
struct vm_fault;
+/**
+ * typedef vm_fault_t - Return type for page fault handlers.
+ *
+ * Page fault handlers return a bitmask of %VM_FAULT values.
+ */
+typedef __bitwise unsigned int vm_fault_t;
+
+/**
+ * enum vm_fault_reason - Page fault handlers return a bitmask of
+ * these values to tell the core VM what happened when handling the
+ * fault. Used to decide whether a process gets delivered SIGBUS or
+ * just gets major/minor fault counters bumped up.
+ *
+ * @VM_FAULT_OOM: Out Of Memory
+ * @VM_FAULT_SIGBUS: Bad access
+ * @VM_FAULT_MAJOR:Page read from storage
+ * @VM_FAULT_WRITE:Special case for get_user_pages
+ * @VM_FAULT_HWPOISON: Hit poisoned small page
+ * @VM_FAULT_HWPOISON_LARGE: Hit poisoned large page. Index encoded
+ * in upper bits
+ * @VM_FAULT_SIGSEGV: segmentation fault
+ * @VM_FAULT_NOPAGE: ->fault installed the pte, not
