From ca6eb14d6453bea85ac66fa4c6ab75dfe93eaf45 Mon Sep 17 00:00:00 2001 From: Peter Xu Date: Fri, 12 Mar 2021 21:07:30 -0800 Subject: mm: use is_cow_mapping() across tree where proper After is_cow_mapping() is exported in mm.h, replace some manual checks elsewhere throughout the tree but start to use the new helper. Link: https://lkml.kernel.org/r/20210217233547.93892-5-peterx@redhat.com Signed-off-by: Peter Xu Reviewed-by: Jason Gunthorpe Cc: VMware Graphics Cc: Roland Scheidegger Cc: David Airlie Cc: Daniel Vetter Cc: Mike Kravetz Cc: Alexey Dobriyan Cc: Andrea Arcangeli Cc: Christoph Hellwig Cc: David Gibson Cc: Gal Pressman Cc: Jan Kara Cc: Jann Horn Cc: Kirill Shutemov Cc: Kirill Tkhai Cc: Matthew Wilcox Cc: Miaohe Lin Cc: Mike Rapoport Cc: Wei Zhang Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/gpu/drm/vmwgfx/vmwgfx_page_dirty.c | 4 +--- drivers/gpu/drm/vmwgfx/vmwgfx_ttm_glue.c | 2 +- 2 files changed, 2 insertions(+), 4 deletions(-) (limited to 'drivers') diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_page_dirty.c b/drivers/gpu/drm/vmwgfx/vmwgfx_page_dirty.c index 0a900afc66ff..45c9c6a7f1d6 100644 --- a/drivers/gpu/drm/vmwgfx/vmwgfx_page_dirty.c +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_page_dirty.c @@ -500,8 +500,6 @@ vm_fault_t vmw_bo_vm_huge_fault(struct vm_fault *vmf, vm_fault_t ret; pgoff_t fault_page_size; bool write = vmf->flags & FAULT_FLAG_WRITE; - bool is_cow_mapping = - (vma->vm_flags & (VM_SHARED | VM_MAYWRITE)) == VM_MAYWRITE; switch (pe_size) { case PE_SIZE_PMD: @@ -518,7 +516,7 @@ vm_fault_t vmw_bo_vm_huge_fault(struct vm_fault *vmf, } /* Always do write dirty-tracking and COW on PTE level. */ - if (write && (READ_ONCE(vbo->dirty) || is_cow_mapping)) + if (write && (READ_ONCE(vbo->dirty) || is_cow_mapping(vma->vm_flags))) return VM_FAULT_FALLBACK; ret = ttm_bo_vm_reserve(bo, vmf); diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_ttm_glue.c b/drivers/gpu/drm/vmwgfx/vmwgfx_ttm_glue.c index 3c03b1746661..cb9975889e2f 100644 --- a/drivers/gpu/drm/vmwgfx/vmwgfx_ttm_glue.c +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_ttm_glue.c @@ -49,7 +49,7 @@ int vmw_mmap(struct file *filp, struct vm_area_struct *vma) vma->vm_ops = &vmw_vm_ops; /* Use VM_PFNMAP rather than VM_MIXEDMAP if not a COW mapping */ - if ((vma->vm_flags & (VM_SHARED | VM_MAYWRITE)) != VM_MAYWRITE) + if (!is_cow_mapping(vma->vm_flags)) vma->vm_flags = (vma->vm_flags & ~VM_MIXEDMAP) | VM_PFNMAP; return 0; -- cgit v1.2.3 From 57e0076e6575a7b7cef620a0bd2ee2549ef77818 Mon Sep 17 00:00:00 2001 From: Minchan Kim Date: Fri, 12 Mar 2021 21:08:38 -0800 Subject: zram: fix return value on writeback_store writeback_store's return value is overwritten by submit_bio_wait's return value. Thus, writeback_store will return zero since there was no IO error. In the end, write syscall from userspace will see the zero as return value, which could make the process stall to keep trying the write until it will succeed. Link: https://lkml.kernel.org/r/20210312173949.2197662-1-minchan@kernel.org Fixes: 3b82a051c101("drivers/block/zram/zram_drv.c: fix error return codes not being returned in writeback_store") Signed-off-by: Minchan Kim Cc: Sergey Senozhatsky Cc: Colin Ian King Cc: John Dias Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/block/zram/zram_drv.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) (limited to 'drivers') diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c index a711a2e2a794..63bbefdffc81 100644 --- a/drivers/block/zram/zram_drv.c +++ b/drivers/block/zram/zram_drv.c @@ -627,7 +627,7 @@ static ssize_t writeback_store(struct device *dev, struct bio_vec bio_vec; struct page *page; ssize_t ret = len; - int mode; + int mode, err; unsigned long blk_idx = 0; if (sysfs_streq(buf, "idle")) @@ -728,12 +728,17 @@ static ssize_t writeback_store(struct device *dev, * XXX: A single page IO would be inefficient for write * but it would be not bad as starter. */ - ret = submit_bio_wait(&bio); - if (ret) { + err = submit_bio_wait(&bio); + if (err) { zram_slot_lock(zram, index); zram_clear_flag(zram, index, ZRAM_UNDER_WB); zram_clear_flag(zram, index, ZRAM_IDLE); zram_slot_unlock(zram, index); + /* + * Return last IO error unless every IO were + * not suceeded. + */ + ret = err; continue; } -- cgit v1.2.3 From 2766f1821600cc7562bae2128ad0b163f744c5d9 Mon Sep 17 00:00:00 2001 From: Minchan Kim Date: Fri, 12 Mar 2021 21:08:41 -0800 Subject: zram: fix broken page writeback commit 0d8359620d9b ("zram: support page writeback") introduced two problems. It overwrites writeback_store's return value as kstrtol's return value, which makes return value zero so user could see zero as return value of write syscall even though it wrote data successfully. It also breaks index value in the loop in that it doesn't increase the index any longer. It means it can write only first starting block index so user couldn't write all idle pages in the zram so lose memory saving chance. This patch fixes those issues. Link: https://lkml.kernel.org/r/20210312173949.2197662-2-minchan@kernel.org Fixes: 0d8359620d9b("zram: support page writeback") Signed-off-by: Minchan Kim Reported-by: Amos Bianchi Cc: Sergey Senozhatsky Cc: John Dias Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/block/zram/zram_drv.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'drivers') diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c index 63bbefdffc81..cf8deecc39ef 100644 --- a/drivers/block/zram/zram_drv.c +++ b/drivers/block/zram/zram_drv.c @@ -638,8 +638,8 @@ static ssize_t writeback_store(struct device *dev, if (strncmp(buf, PAGE_WB_SIG, sizeof(PAGE_WB_SIG) - 1)) return -EINVAL; - ret = kstrtol(buf + sizeof(PAGE_WB_SIG) - 1, 10, &index); - if (ret || index >= nr_pages) + if (kstrtol(buf + sizeof(PAGE_WB_SIG) - 1, 10, &index) || + index >= nr_pages) return -EINVAL; nr_pages = 1; @@ -663,7 +663,7 @@ static ssize_t writeback_store(struct device *dev, goto release_init_lock; } - while (nr_pages--) { + for (; nr_pages != 0; index++, nr_pages--) { struct bio_vec bvec; bvec.bv_page = page; -- cgit v1.2.3