| Message ID | 20180709122019eucas1p2340da484acfcc932537e6014f4fd2c29~-sqTPJKij2939229392eucas1p2j@eucas1p2.samsung.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Mon 09-07-18 14:19:55, Marek Szyprowski wrote: > cma_alloc() function doesn't really support gfp flags other than > __GFP_NOWARN, so convert gfp_mask parameter to boolean no_warn parameter. > > This will help to avoid giving false feeling that this function supports > standard gfp flags and callers can pass __GFP_ZERO to get zeroed buffer, > what has already been an issue: see commit dd65a941f6ba ("arm64: > dma-mapping: clear buffers allocated with FORCE_CONTIGUOUS flag"). > > Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Thanks! This makes perfect sense to me. If there is a real need for the gfp_mask then we should start by defining the semantic first. Acked-by: Michal Hocko <mhocko@suse.com> > --- > arch/powerpc/kvm/book3s_hv_builtin.c | 2 +- > drivers/s390/char/vmcp.c | 2 +- > drivers/staging/android/ion/ion_cma_heap.c | 2 +- > include/linux/cma.h | 2 +- > kernel/dma/contiguous.c | 3 ++- > mm/cma.c | 8 ++++---- > mm/cma_debug.c | 2 +- > 7 files changed, 11 insertions(+), 10 deletions(-) > > diff --git a/arch/powerpc/kvm/book3s_hv_builtin.c b/arch/powerpc/kvm/book3s_hv_builtin.c > index d4a3f4da409b..fc6bb9630a9c 100644 > --- a/arch/powerpc/kvm/book3s_hv_builtin.c > +++ b/arch/powerpc/kvm/book3s_hv_builtin.c > @@ -77,7 +77,7 @@ struct page *kvm_alloc_hpt_cma(unsigned long nr_pages) > VM_BUG_ON(order_base_2(nr_pages) < KVM_CMA_CHUNK_ORDER - PAGE_SHIFT); > > return cma_alloc(kvm_cma, nr_pages, order_base_2(HPT_ALIGN_PAGES), > - GFP_KERNEL); > + false); > } > EXPORT_SYMBOL_GPL(kvm_alloc_hpt_cma); > > diff --git a/drivers/s390/char/vmcp.c b/drivers/s390/char/vmcp.c > index 948ce82a7725..0fa1b6b1491a 100644 > --- a/drivers/s390/char/vmcp.c > +++ b/drivers/s390/char/vmcp.c > @@ -68,7 +68,7 @@ static void vmcp_response_alloc(struct vmcp_session *session) > * anymore the system won't work anyway. > */ > if (order > 2) > - page = cma_alloc(vmcp_cma, nr_pages, 0, GFP_KERNEL); > + page = cma_alloc(vmcp_cma, nr_pages, 0, false); > if (page) { > session->response = (char *)page_to_phys(page); > session->cma_alloc = 1; > diff --git a/drivers/staging/android/ion/ion_cma_heap.c b/drivers/staging/android/ion/ion_cma_heap.c > index 49718c96bf9e..3fafd013d80a 100644 > --- a/drivers/staging/android/ion/ion_cma_heap.c > +++ b/drivers/staging/android/ion/ion_cma_heap.c > @@ -39,7 +39,7 @@ static int ion_cma_allocate(struct ion_heap *heap, struct ion_buffer *buffer, > if (align > CONFIG_CMA_ALIGNMENT) > align = CONFIG_CMA_ALIGNMENT; > > - pages = cma_alloc(cma_heap->cma, nr_pages, align, GFP_KERNEL); > + pages = cma_alloc(cma_heap->cma, nr_pages, align, false); > if (!pages) > return -ENOMEM; > > diff --git a/include/linux/cma.h b/include/linux/cma.h > index bf90f0bb42bd..190184b5ff32 100644 > --- a/include/linux/cma.h > +++ b/include/linux/cma.h > @@ -33,7 +33,7 @@ extern int cma_init_reserved_mem(phys_addr_t base, phys_addr_t size, > const char *name, > struct cma **res_cma); > extern struct page *cma_alloc(struct cma *cma, size_t count, unsigned int align, > - gfp_t gfp_mask); > + bool no_warn); > extern bool cma_release(struct cma *cma, const struct page *pages, unsigned int count); > > extern int cma_for_each_area(int (*it)(struct cma *cma, void *data), void *data); > diff --git a/kernel/dma/contiguous.c b/kernel/dma/contiguous.c > index d987dcd1bd56..19ea5d70150c 100644 > --- a/kernel/dma/contiguous.c > +++ b/kernel/dma/contiguous.c > @@ -191,7 +191,8 @@ struct page *dma_alloc_from_contiguous(struct device *dev, size_t count, > if (align > CONFIG_CMA_ALIGNMENT) > align = CONFIG_CMA_ALIGNMENT; > > - return cma_alloc(dev_get_cma_area(dev), count, align, gfp_mask); > + return cma_alloc(dev_get_cma_area(dev), count, align, > + gfp_mask & __GFP_NOWARN); > } > > /** > diff --git a/mm/cma.c b/mm/cma.c > index 5809bbe360d7..4cb76121a3ab 100644 > --- a/mm/cma.c > +++ b/mm/cma.c > @@ -395,13 +395,13 @@ static inline void cma_debug_show_areas(struct cma *cma) { } > * @cma: Contiguous memory region for which the allocation is performed. > * @count: Requested number of pages. > * @align: Requested alignment of pages (in PAGE_SIZE order). > - * @gfp_mask: GFP mask to use during compaction > + * @no_warn: Avoid printing message about failed allocation > * > * This function allocates part of contiguous memory on specific > * contiguous memory area. > */ > struct page *cma_alloc(struct cma *cma, size_t count, unsigned int align, > - gfp_t gfp_mask) > + bool no_warn) > { > unsigned long mask, offset; > unsigned long pfn = -1; > @@ -447,7 +447,7 @@ struct page *cma_alloc(struct cma *cma, size_t count, unsigned int align, > pfn = cma->base_pfn + (bitmap_no << cma->order_per_bit); > mutex_lock(&cma_mutex); > ret = alloc_contig_range(pfn, pfn + count, MIGRATE_CMA, > - gfp_mask); > + GFP_KERNEL | (no_warn ? __GFP_NOWARN : 0)); > mutex_unlock(&cma_mutex); > if (ret == 0) { > page = pfn_to_page(pfn); > @@ -466,7 +466,7 @@ struct page *cma_alloc(struct cma *cma, size_t count, unsigned int align, > > trace_cma_alloc(pfn, page, count, align)> > - if (ret && !(gfp_mask & __GFP_NOWARN)) { > + if (ret && !no_warn) { > pr_err("%s: alloc failed, req-size: %zu pages, ret: %d\n", > __func__, count, ret); > cma_debug_show_areas(cma); > diff --git a/mm/cma_debug.c b/mm/cma_debug.c > index f23467291cfb..ad6723e9d110 100644 > --- a/mm/cma_debug.c > +++ b/mm/cma_debug.c > @@ -139,7 +139,7 @@ static int cma_alloc_mem(struct cma *cma, int count) > if (!mem) > return -ENOMEM; > > - p = cma_alloc(cma, count, 0, GFP_KERNEL); > + p = cma_alloc(cma, count, 0, false); > if (!p) { > kfree(mem); > return -ENOMEM; > -- > 2.17.1 >
On 07/09/2018 05:19 AM, Marek Szyprowski wrote: > cma_alloc() function doesn't really support gfp flags other than > __GFP_NOWARN, so convert gfp_mask parameter to boolean no_warn parameter. > > This will help to avoid giving false feeling that this function supports > standard gfp flags and callers can pass __GFP_ZERO to get zeroed buffer, > what has already been an issue: see commit dd65a941f6ba ("arm64: > dma-mapping: clear buffers allocated with FORCE_CONTIGUOUS flag"). > For Ion, Acked-by: Laura Abbott <labbott@redhat.com> > Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> > --- > arch/powerpc/kvm/book3s_hv_builtin.c | 2 +- > drivers/s390/char/vmcp.c | 2 +- > drivers/staging/android/ion/ion_cma_heap.c | 2 +- > include/linux/cma.h | 2 +- > kernel/dma/contiguous.c | 3 ++- > mm/cma.c | 8 ++++---- > mm/cma_debug.c | 2 +- > 7 files changed, 11 insertions(+), 10 deletions(-) > > diff --git a/arch/powerpc/kvm/book3s_hv_builtin.c b/arch/powerpc/kvm/book3s_hv_builtin.c > index d4a3f4da409b..fc6bb9630a9c 100644 > --- a/arch/powerpc/kvm/book3s_hv_builtin.c > +++ b/arch/powerpc/kvm/book3s_hv_builtin.c > @@ -77,7 +77,7 @@ struct page *kvm_alloc_hpt_cma(unsigned long nr_pages) > VM_BUG_ON(order_base_2(nr_pages) < KVM_CMA_CHUNK_ORDER - PAGE_SHIFT); > > return cma_alloc(kvm_cma, nr_pages, order_base_2(HPT_ALIGN_PAGES), > - GFP_KERNEL); > + false); > } > EXPORT_SYMBOL_GPL(kvm_alloc_hpt_cma); > > diff --git a/drivers/s390/char/vmcp.c b/drivers/s390/char/vmcp.c > index 948ce82a7725..0fa1b6b1491a 100644 > --- a/drivers/s390/char/vmcp.c > +++ b/drivers/s390/char/vmcp.c > @@ -68,7 +68,7 @@ static void vmcp_response_alloc(struct vmcp_session *session) > * anymore the system won't work anyway. > */ > if (order > 2) > - page = cma_alloc(vmcp_cma, nr_pages, 0, GFP_KERNEL); > + page = cma_alloc(vmcp_cma, nr_pages, 0, false); > if (page) { > session->response = (char *)page_to_phys(page); > session->cma_alloc = 1; > diff --git a/drivers/staging/android/ion/ion_cma_heap.c b/drivers/staging/android/ion/ion_cma_heap.c > index 49718c96bf9e..3fafd013d80a 100644 > --- a/drivers/staging/android/ion/ion_cma_heap.c > +++ b/drivers/staging/android/ion/ion_cma_heap.c > @@ -39,7 +39,7 @@ static int ion_cma_allocate(struct ion_heap *heap, struct ion_buffer *buffer, > if (align > CONFIG_CMA_ALIGNMENT) > align = CONFIG_CMA_ALIGNMENT; > > - pages = cma_alloc(cma_heap->cma, nr_pages, align, GFP_KERNEL); > + pages = cma_alloc(cma_heap->cma, nr_pages, align, false); > if (!pages) > return -ENOMEM; > > diff --git a/include/linux/cma.h b/include/linux/cma.h > index bf90f0bb42bd..190184b5ff32 100644 > --- a/include/linux/cma.h > +++ b/include/linux/cma.h > @@ -33,7 +33,7 @@ extern int cma_init_reserved_mem(phys_addr_t base, phys_addr_t size, > const char *name, > struct cma **res_cma); > extern struct page *cma_alloc(struct cma *cma, size_t count, unsigned int align, > - gfp_t gfp_mask); > + bool no_warn); > extern bool cma_release(struct cma *cma, const struct page *pages, unsigned int count); > > extern int cma_for_each_area(int (*it)(struct cma *cma, void *data), void *data); > diff --git a/kernel/dma/contiguous.c b/kernel/dma/contiguous.c > index d987dcd1bd56..19ea5d70150c 100644 > --- a/kernel/dma/contiguous.c > +++ b/kernel/dma/contiguous.c > @@ -191,7 +191,8 @@ struct page *dma_alloc_from_contiguous(struct device *dev, size_t count, > if (align > CONFIG_CMA_ALIGNMENT) > align = CONFIG_CMA_ALIGNMENT; > > - return cma_alloc(dev_get_cma_area(dev), count, align, gfp_mask); > + return cma_alloc(dev_get_cma_area(dev), count, align, > + gfp_mask & __GFP_NOWARN); > } > > /** > diff --git a/mm/cma.c b/mm/cma.c > index 5809bbe360d7..4cb76121a3ab 100644 > --- a/mm/cma.c > +++ b/mm/cma.c > @@ -395,13 +395,13 @@ static inline void cma_debug_show_areas(struct cma *cma) { } > * @cma: Contiguous memory region for which the allocation is performed. > * @count: Requested number of pages. > * @align: Requested alignment of pages (in PAGE_SIZE order). > - * @gfp_mask: GFP mask to use during compaction > + * @no_warn: Avoid printing message about failed allocation > * > * This function allocates part of contiguous memory on specific > * contiguous memory area. > */ > struct page *cma_alloc(struct cma *cma, size_t count, unsigned int align, > - gfp_t gfp_mask) > + bool no_warn) > { > unsigned long mask, offset; > unsigned long pfn = -1; > @@ -447,7 +447,7 @@ struct page *cma_alloc(struct cma *cma, size_t count, unsigned int align, > pfn = cma->base_pfn + (bitmap_no << cma->order_per_bit); > mutex_lock(&cma_mutex); > ret = alloc_contig_range(pfn, pfn + count, MIGRATE_CMA, > - gfp_mask); > + GFP_KERNEL | (no_warn ? __GFP_NOWARN : 0)); > mutex_unlock(&cma_mutex); > if (ret == 0) { > page = pfn_to_page(pfn); > @@ -466,7 +466,7 @@ struct page *cma_alloc(struct cma *cma, size_t count, unsigned int align, > > trace_cma_alloc(pfn, page, count, align); > > - if (ret && !(gfp_mask & __GFP_NOWARN)) { > + if (ret && !no_warn) { > pr_err("%s: alloc failed, req-size: %zu pages, ret: %d\n", > __func__, count, ret); > cma_debug_show_areas(cma); > diff --git a/mm/cma_debug.c b/mm/cma_debug.c > index f23467291cfb..ad6723e9d110 100644 > --- a/mm/cma_debug.c > +++ b/mm/cma_debug.c > @@ -139,7 +139,7 @@ static int cma_alloc_mem(struct cma *cma, int count) > if (!mem) > return -ENOMEM; > > - p = cma_alloc(cma, count, 0, GFP_KERNEL); > + p = cma_alloc(cma, count, 0, false); > if (!p) { > kfree(mem); > return -ENOMEM; >
Hello, Marek. 2018-07-09 21:19 GMT+09:00 Marek Szyprowski <m.szyprowski@samsung.com>: > cma_alloc() function doesn't really support gfp flags other than > __GFP_NOWARN, so convert gfp_mask parameter to boolean no_warn parameter. Although gfp_mask isn't used in cma_alloc() except no_warn, it can be used in alloc_contig_range(). For example, if passed gfp mask has no __GFP_FS, compaction(isolation) would work differently. Do you have considered such a case? Thanks.
On Tue 10-07-18 16:19:32, Joonsoo Kim wrote: > Hello, Marek. > > 2018-07-09 21:19 GMT+09:00 Marek Szyprowski <m.szyprowski@samsung.com>: > > cma_alloc() function doesn't really support gfp flags other than > > __GFP_NOWARN, so convert gfp_mask parameter to boolean no_warn parameter. > > Although gfp_mask isn't used in cma_alloc() except no_warn, it can be used > in alloc_contig_range(). For example, if passed gfp mask has no __GFP_FS, > compaction(isolation) would work differently. Do you have considered > such a case? Does any of cma_alloc users actually care about GFP_NO{FS,IO}?
2018-07-10 18:50 GMT+09:00 Michal Hocko <mhocko@kernel.org>: > On Tue 10-07-18 16:19:32, Joonsoo Kim wrote: >> Hello, Marek. >> >> 2018-07-09 21:19 GMT+09:00 Marek Szyprowski <m.szyprowski@samsung.com>: >> > cma_alloc() function doesn't really support gfp flags other than >> > __GFP_NOWARN, so convert gfp_mask parameter to boolean no_warn parameter. >> >> Although gfp_mask isn't used in cma_alloc() except no_warn, it can be used >> in alloc_contig_range(). For example, if passed gfp mask has no __GFP_FS, >> compaction(isolation) would work differently. Do you have considered >> such a case? > > Does any of cma_alloc users actually care about GFP_NO{FS,IO}? I don't know. My guess is that cma_alloc() is used for DMA allocation so block device would use it, too. If fs/block subsystem initiates the request for the device, it would be possible that cma_alloc() is called with such a flag. Again, I don't know much about those subsystem so I would be wrong. Thanks.
On Wed 11-07-18 16:35:28, Joonsoo Kim wrote: > 2018-07-10 18:50 GMT+09:00 Michal Hocko <mhocko@kernel.org>: > > On Tue 10-07-18 16:19:32, Joonsoo Kim wrote: > >> Hello, Marek. > >> > >> 2018-07-09 21:19 GMT+09:00 Marek Szyprowski <m.szyprowski@samsung.com>: > >> > cma_alloc() function doesn't really support gfp flags other than > >> > __GFP_NOWARN, so convert gfp_mask parameter to boolean no_warn parameter. > >> > >> Although gfp_mask isn't used in cma_alloc() except no_warn, it can be used > >> in alloc_contig_range(). For example, if passed gfp mask has no __GFP_FS, > >> compaction(isolation) would work differently. Do you have considered > >> such a case? > > > > Does any of cma_alloc users actually care about GFP_NO{FS,IO}? > > I don't know. My guess is that cma_alloc() is used for DMA allocation so > block device would use it, too. If fs/block subsystem initiates the > request for the device, > it would be possible that cma_alloc() is called with such a flag. > Again, I don't know > much about those subsystem so I would be wrong. The patch converts existing users and none of them really tries to use anything other than GFP_KERNEL [|__GFP_NOWARN] so this doesn't seem to be the case. Should there be a new user requiring more restricted gfp_mask we should carefuly re-evaluate and think how to support it. Until then I would simply stick with the proposed approach because my experience tells me that a wrong gfp mask usage is way too easy so the simpler the api is the less likely we will see an abuse.
2018-07-11 17:54 GMT+09:00 Michal Hocko <mhocko@kernel.org>: > On Wed 11-07-18 16:35:28, Joonsoo Kim wrote: >> 2018-07-10 18:50 GMT+09:00 Michal Hocko <mhocko@kernel.org>: >> > On Tue 10-07-18 16:19:32, Joonsoo Kim wrote: >> >> Hello, Marek. >> >> >> >> 2018-07-09 21:19 GMT+09:00 Marek Szyprowski <m.szyprowski@samsung.com>: >> >> > cma_alloc() function doesn't really support gfp flags other than >> >> > __GFP_NOWARN, so convert gfp_mask parameter to boolean no_warn parameter. >> >> >> >> Although gfp_mask isn't used in cma_alloc() except no_warn, it can be used >> >> in alloc_contig_range(). For example, if passed gfp mask has no __GFP_FS, >> >> compaction(isolation) would work differently. Do you have considered >> >> such a case? >> > >> > Does any of cma_alloc users actually care about GFP_NO{FS,IO}? >> >> I don't know. My guess is that cma_alloc() is used for DMA allocation so >> block device would use it, too. If fs/block subsystem initiates the >> request for the device, >> it would be possible that cma_alloc() is called with such a flag. >> Again, I don't know >> much about those subsystem so I would be wrong. > > The patch converts existing users and none of them really tries to use > anything other than GFP_KERNEL [|__GFP_NOWARN] so this doesn't seem to > be the case. Should there be a new user requiring more restricted > gfp_mask we should carefuly re-evaluate and think how to support it. One of existing user is general DMA layer and it takes gfp flags that is provided by user. I don't check all the DMA allocation sites but how do you convince that none of them try to use anything other than GFP_KERNEL [|__GFP_NOWARN]? Thanks.
On Thu, Jul 12, 2018 at 11:48:47AM +0900, Joonsoo Kim wrote: > One of existing user is general DMA layer and it takes gfp flags that is > provided by user. I don't check all the DMA allocation sites but how do > you convince that none of them try to use anything other > than GFP_KERNEL [|__GFP_NOWARN]? They use a few others things still like __GFP_COMP, __GPF_DMA or GFP_HUGEPAGE. But all these are bogus as we have various implementations that can't respect them. I plan to get rid of the gfp_t argument in the dma_map_ops alloc method in a few merge windows because of that, but it needs further implementation consolidation first.
2018-07-12 16:15 GMT+09:00 Christoph Hellwig <hch@lst.de>: > On Thu, Jul 12, 2018 at 11:48:47AM +0900, Joonsoo Kim wrote: >> One of existing user is general DMA layer and it takes gfp flags that is >> provided by user. I don't check all the DMA allocation sites but how do >> you convince that none of them try to use anything other >> than GFP_KERNEL [|__GFP_NOWARN]? > > They use a few others things still like __GFP_COMP, __GPF_DMA or > GFP_HUGEPAGE. But all these are bogus as we have various implementations > that can't respect them. I plan to get rid of the gfp_t argument > in the dma_map_ops alloc method in a few merge windows because of that, > but it needs further implementation consolidation first. Okay. If those flags are all, this change would be okay. For the remind of this gfp flag introduction in cma_alloc(), see the following link. https://marc.info/?l=linux-mm&m=148431452118407 Thanks.
On 07/09/2018 02:19 PM, Marek Szyprowski wrote: > cma_alloc() function doesn't really support gfp flags other than > __GFP_NOWARN, so convert gfp_mask parameter to boolean no_warn parameter. > > This will help to avoid giving false feeling that this function supports > standard gfp flags and callers can pass __GFP_ZERO to get zeroed buffer, > what has already been an issue: see commit dd65a941f6ba ("arm64: > dma-mapping: clear buffers allocated with FORCE_CONTIGUOUS flag"). > > Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Acked-by: Vlastimil Babka <vbabka@suse.cz>
Looks good:
Reviewed-by: Christoph Hellwig <hch@lst.de>
diff --git a/arch/powerpc/kvm/book3s_hv_builtin.c b/arch/powerpc/kvm/book3s_hv_builtin.c index d4a3f4da409b..fc6bb9630a9c 100644 --- a/arch/powerpc/kvm/book3s_hv_builtin.c +++ b/arch/powerpc/kvm/book3s_hv_builtin.c @@ -77,7 +77,7 @@ struct page *kvm_alloc_hpt_cma(unsigned long nr_pages) VM_BUG_ON(order_base_2(nr_pages) < KVM_CMA_CHUNK_ORDER - PAGE_SHIFT); return cma_alloc(kvm_cma, nr_pages, order_base_2(HPT_ALIGN_PAGES), - GFP_KERNEL); + false); } EXPORT_SYMBOL_GPL(kvm_alloc_hpt_cma); diff --git a/drivers/s390/char/vmcp.c b/drivers/s390/char/vmcp.c index 948ce82a7725..0fa1b6b1491a 100644 --- a/drivers/s390/char/vmcp.c +++ b/drivers/s390/char/vmcp.c @@ -68,7 +68,7 @@ static void vmcp_response_alloc(struct vmcp_session *session) * anymore the system won't work anyway. */ if (order > 2) - page = cma_alloc(vmcp_cma, nr_pages, 0, GFP_KERNEL); + page = cma_alloc(vmcp_cma, nr_pages, 0, false); if (page) { session->response = (char *)page_to_phys(page); session->cma_alloc = 1; diff --git a/drivers/staging/android/ion/ion_cma_heap.c b/drivers/staging/android/ion/ion_cma_heap.c index 49718c96bf9e..3fafd013d80a 100644 --- a/drivers/staging/android/ion/ion_cma_heap.c +++ b/drivers/staging/android/ion/ion_cma_heap.c @@ -39,7 +39,7 @@ static int ion_cma_allocate(struct ion_heap *heap, struct ion_buffer *buffer, if (align > CONFIG_CMA_ALIGNMENT) align = CONFIG_CMA_ALIGNMENT; - pages = cma_alloc(cma_heap->cma, nr_pages, align, GFP_KERNEL); + pages = cma_alloc(cma_heap->cma, nr_pages, align, false); if (!pages) return -ENOMEM; diff --git a/include/linux/cma.h b/include/linux/cma.h index bf90f0bb42bd..190184b5ff32 100644 --- a/include/linux/cma.h +++ b/include/linux/cma.h @@ -33,7 +33,7 @@ extern int cma_init_reserved_mem(phys_addr_t base, phys_addr_t size, const char *name, struct cma **res_cma); extern struct page *cma_alloc(struct cma *cma, size_t count, unsigned int align, - gfp_t gfp_mask); + bool no_warn); extern bool cma_release(struct cma *cma, const struct page *pages, unsigned int count); extern int cma_for_each_area(int (*it)(struct cma *cma, void *data), void *data); diff --git a/kernel/dma/contiguous.c b/kernel/dma/contiguous.c index d987dcd1bd56..19ea5d70150c 100644 --- a/kernel/dma/contiguous.c +++ b/kernel/dma/contiguous.c @@ -191,7 +191,8 @@ struct page *dma_alloc_from_contiguous(struct device *dev, size_t count, if (align > CONFIG_CMA_ALIGNMENT) align = CONFIG_CMA_ALIGNMENT; - return cma_alloc(dev_get_cma_area(dev), count, align, gfp_mask); + return cma_alloc(dev_get_cma_area(dev), count, align, + gfp_mask & __GFP_NOWARN); } /** diff --git a/mm/cma.c b/mm/cma.c index 5809bbe360d7..4cb76121a3ab 100644 --- a/mm/cma.c +++ b/mm/cma.c @@ -395,13 +395,13 @@ static inline void cma_debug_show_areas(struct cma *cma) { } * @cma: Contiguous memory region for which the allocation is performed. * @count: Requested number of pages. * @align: Requested alignment of pages (in PAGE_SIZE order). - * @gfp_mask: GFP mask to use during compaction + * @no_warn: Avoid printing message about failed allocation * * This function allocates part of contiguous memory on specific * contiguous memory area. */ struct page *cma_alloc(struct cma *cma, size_t count, unsigned int align, - gfp_t gfp_mask) + bool no_warn) { unsigned long mask, offset; unsigned long pfn = -1; @@ -447,7 +447,7 @@ struct page *cma_alloc(struct cma *cma, size_t count, unsigned int align, pfn = cma->base_pfn + (bitmap_no << cma->order_per_bit); mutex_lock(&cma_mutex); ret = alloc_contig_range(pfn, pfn + count, MIGRATE_CMA, - gfp_mask); + GFP_KERNEL | (no_warn ? __GFP_NOWARN : 0)); mutex_unlock(&cma_mutex); if (ret == 0) { page = pfn_to_page(pfn); @@ -466,7 +466,7 @@ struct page *cma_alloc(struct cma *cma, size_t count, unsigned int align, trace_cma_alloc(pfn, page, count, align); - if (ret && !(gfp_mask & __GFP_NOWARN)) { + if (ret && !no_warn) { pr_err("%s: alloc failed, req-size: %zu pages, ret: %d\n", __func__, count, ret); cma_debug_show_areas(cma); diff --git a/mm/cma_debug.c b/mm/cma_debug.c index f23467291cfb..ad6723e9d110 100644 --- a/mm/cma_debug.c +++ b/mm/cma_debug.c @@ -139,7 +139,7 @@ static int cma_alloc_mem(struct cma *cma, int count) if (!mem) return -ENOMEM; - p = cma_alloc(cma, count, 0, GFP_KERNEL); + p = cma_alloc(cma, count, 0, false); if (!p) { kfree(mem); return -ENOMEM;
cma_alloc() function doesn't really support gfp flags other than __GFP_NOWARN, so convert gfp_mask parameter to boolean no_warn parameter. This will help to avoid giving false feeling that this function supports standard gfp flags and callers can pass __GFP_ZERO to get zeroed buffer, what has already been an issue: see commit dd65a941f6ba ("arm64: dma-mapping: clear buffers allocated with FORCE_CONTIGUOUS flag"). Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> --- arch/powerpc/kvm/book3s_hv_builtin.c | 2 +- drivers/s390/char/vmcp.c | 2 +- drivers/staging/android/ion/ion_cma_heap.c | 2 +- include/linux/cma.h | 2 +- kernel/dma/contiguous.c | 3 ++- mm/cma.c | 8 ++++---- mm/cma_debug.c | 2 +- 7 files changed, 11 insertions(+), 10 deletions(-)