From: Christoph Hellwig Subject: [PATCH 05/14] ceph: untangle ceph_filemap_fault Date: Wed, 16 May 2018 07:43:39 +0200 Message-ID: <20180516054348.15950-6-hch@lst.de> References: <20180516054348.15950-1-hch@lst.de> Cc: linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, devel@lists.orangefs.org, ceph-devel@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-ext4@vger.kernel.org, ocfs2-devel@oss.oracle.com, linux-mtd@lists.infradead.org, dri-devel@lists.freedesktop.org, lustre-devel@lists.lustre.org, linux-arm-kernel@lists.infradead.org, linux-s390@vger.kernel.org To: Souptick Joarder , Matthew Wilcox Return-path: In-Reply-To: <20180516054348.15950-1-hch@lst.de> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org Streamline the code to have a somewhat natural flow, and separate the errno values from the VM_FAULT_* values. Signed-off-by: Christoph Hellwig --- fs/ceph/addr.c | 100 +++++++++++++++++++++++++------------------------ 1 file changed, 51 insertions(+), 49 deletions(-) diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c index 5f7ad3d0df2e..6e80894ca073 100644 --- a/fs/ceph/addr.c +++ b/fs/ceph/addr.c @@ -1428,15 +1428,18 @@ static void ceph_restore_sigs(sigset_t *oldset) /* * vm ops */ -static int ceph_filemap_fault(struct vm_fault *vmf) +static vm_fault_t ceph_filemap_fault(struct vm_fault *vmf) { struct vm_area_struct *vma = vmf->vma; struct inode *inode = file_inode(vma->vm_file); + struct address_space *mapping = inode->i_mapping; struct ceph_inode_info *ci = ceph_inode(inode); struct ceph_file_info *fi = vma->vm_file->private_data; - struct page *pinned_page = NULL; + struct page *pinned_page = NULL, *page; loff_t off = vmf->pgoff << PAGE_SHIFT; - int want, got, ret; + int want, got, err = 0; + vm_fault_t ret = 0; + bool did_fault = false; sigset_t oldset; ceph_block_sigs(&oldset); @@ -1449,9 +1452,9 @@ static int ceph_filemap_fault(struct vm_fault *vmf) want = CEPH_CAP_FILE_CACHE; got = 0; - ret = ceph_get_caps(ci, CEPH_CAP_FILE_RD, want, -1, &got, &pinned_page); - if (ret < 0) - goto out_restore; + err = ceph_get_caps(ci, CEPH_CAP_FILE_RD, want, -1, &got, &pinned_page); + if (err < 0) + goto out_errno; dout("filemap_fault %p %llu~%zd got cap refs on %s\n", inode, off, (size_t)PAGE_SIZE, ceph_cap_string(got)); @@ -1462,8 +1465,8 @@ static int ceph_filemap_fault(struct vm_fault *vmf) ceph_add_rw_context(fi, &rw_ctx); ret = filemap_fault(vmf); ceph_del_rw_context(fi, &rw_ctx); - } else - ret = -EAGAIN; + did_fault = true; + } dout("filemap_fault %p %llu~%zd dropping cap refs on %s ret %d\n", inode, off, (size_t)PAGE_SIZE, ceph_cap_string(got), ret); @@ -1471,57 +1474,55 @@ static int ceph_filemap_fault(struct vm_fault *vmf) put_page(pinned_page); ceph_put_cap_refs(ci, got); - if (ret != -EAGAIN) + if (did_fault) goto out_restore; /* read inline data */ if (off >= PAGE_SIZE) { /* does not support inline data > PAGE_SIZE */ ret = VM_FAULT_SIGBUS; + goto out_restore; + } + + page = find_or_create_page(mapping, 0, + mapping_gfp_constraint(mapping, ~__GFP_FS)); + if (!page) { + ret = VM_FAULT_OOM; + goto out_inline; + } + + err = __ceph_do_getattr(inode, page, CEPH_STAT_CAP_INLINE_DATA, true); + if (err < 0 || off >= i_size_read(inode)) { + unlock_page(page); + put_page(page); + if (err < 0) + goto out_errno; + ret = VM_FAULT_SIGBUS; } else { - int ret1; - struct address_space *mapping = inode->i_mapping; - struct page *page = find_or_create_page(mapping, 0, - mapping_gfp_constraint(mapping, - ~__GFP_FS)); - if (!page) { - ret = VM_FAULT_OOM; - goto out_inline; - } - ret1 = __ceph_do_getattr(inode, page, - CEPH_STAT_CAP_INLINE_DATA, true); - if (ret1 < 0 || off >= i_size_read(inode)) { - unlock_page(page); - put_page(page); - if (ret1 < 0) - ret = ret1; - else - ret = VM_FAULT_SIGBUS; - goto out_inline; - } - if (ret1 < PAGE_SIZE) - zero_user_segment(page, ret1, PAGE_SIZE); + if (err < PAGE_SIZE) + zero_user_segment(page, err, PAGE_SIZE); else flush_dcache_page(page); SetPageUptodate(page); vmf->page = page; ret = VM_FAULT_MAJOR | VM_FAULT_LOCKED; -out_inline: - dout("filemap_fault %p %llu~%zd read inline data ret %d\n", - inode, off, (size_t)PAGE_SIZE, ret); } + +out_inline: + dout("filemap_fault %p %llu~%zd read inline data ret %d\n", + inode, off, (size_t)PAGE_SIZE, ret); out_restore: ceph_restore_sigs(&oldset); - if (ret < 0) - ret = (ret == -ENOMEM) ? VM_FAULT_OOM : VM_FAULT_SIGBUS; - return ret; +out_errno: + ret = (err == -ENOMEM) ? VM_FAULT_OOM : VM_FAULT_SIGBUS; + goto out_restore; } /* * Reuse write_begin here for simplicity. */ -static int ceph_page_mkwrite(struct vm_fault *vmf) +static vm_fault_t ceph_page_mkwrite(struct vm_fault *vmf) { struct vm_area_struct *vma = vmf->vma; struct inode *inode = file_inode(vma->vm_file); @@ -1532,7 +1533,8 @@ static int ceph_page_mkwrite(struct vm_fault *vmf) loff_t off = page_offset(page); loff_t size = i_size_read(inode); size_t len; - int want, got, ret; + int want, got, err = 0; + vm_fault_t ret = 0; sigset_t oldset; prealloc_cf = ceph_alloc_cap_flush(); @@ -1547,10 +1549,10 @@ static int ceph_page_mkwrite(struct vm_fault *vmf) lock_page(page); locked_page = page; } - ret = ceph_uninline_data(vma->vm_file, locked_page); + err = ceph_uninline_data(vma->vm_file, locked_page); if (locked_page) unlock_page(locked_page); - if (ret < 0) + if (err < 0) goto out_free; } @@ -1567,9 +1569,9 @@ static int ceph_page_mkwrite(struct vm_fault *vmf) want = CEPH_CAP_FILE_BUFFER; got = 0; - ret = ceph_get_caps(ci, CEPH_CAP_FILE_WR, want, off + len, + err = ceph_get_caps(ci, CEPH_CAP_FILE_WR, want, off + len, &got, NULL); - if (ret < 0) + if (err < 0) goto out_free; dout("page_mkwrite %p %llu~%zd got cap refs on %s\n", @@ -1587,13 +1589,13 @@ static int ceph_page_mkwrite(struct vm_fault *vmf) break; } - ret = ceph_update_writeable_page(vma->vm_file, off, len, page); - if (ret >= 0) { + err = ceph_update_writeable_page(vma->vm_file, off, len, page); + if (err >= 0) { /* success. we'll keep the page locked. */ set_page_dirty(page); ret = VM_FAULT_LOCKED; } - } while (ret == -EAGAIN); + } while (err == -EAGAIN); if (ret == VM_FAULT_LOCKED || ci->i_inline_version != CEPH_INLINE_NONE) { @@ -1608,13 +1610,13 @@ static int ceph_page_mkwrite(struct vm_fault *vmf) } dout("page_mkwrite %p %llu~%zd dropping cap refs on %s ret %d\n", - inode, off, len, ceph_cap_string(got), ret); + inode, off, len, ceph_cap_string(got), err); ceph_put_cap_refs(ci, got); out_free: ceph_restore_sigs(&oldset); ceph_free_cap_flush(prealloc_cf); - if (ret < 0) - ret = (ret == -ENOMEM) ? VM_FAULT_OOM : VM_FAULT_SIGBUS; + if (err < 0) + ret = (err == -ENOMEM) ? VM_FAULT_OOM : VM_FAULT_SIGBUS; return ret; } -- 2.17.0