From ab226e21ad34f6ef52e00d2ab399d2364b4cdfee Mon Sep 17 00:00:00 2001 From: Henry C Chang Date: Wed, 15 Dec 2010 20:41:54 -0800 Subject: ceph: fix direct-io on non-page-aligned buffers The user buffer may be 512-byte aligned, not page-aligned. We were assuming the buffer was page-aligned and only accounting for non-page-aligned io offsets. Signed-off-by: Henry C Chang Signed-off-by: Sage Weil --- fs/ceph/file.c | 31 +++++++++++++++++++------------ 1 file changed, 19 insertions(+), 12 deletions(-) (limited to 'fs') diff --git a/fs/ceph/file.c b/fs/ceph/file.c index 8d79b8912e31..e860d8f1bb45 100644 --- a/fs/ceph/file.c +++ b/fs/ceph/file.c @@ -282,7 +282,8 @@ int ceph_release(struct inode *inode, struct file *file) static int striped_read(struct inode *inode, u64 off, u64 len, struct page **pages, int num_pages, - int *checkeof, bool align_to_pages) + int *checkeof, bool align_to_pages, + unsigned long buf_align) { struct ceph_fs_client *fsc = ceph_inode_to_client(inode); struct ceph_inode_info *ci = ceph_inode(inode); @@ -307,7 +308,7 @@ static int striped_read(struct inode *inode, more: if (align_to_pages) - page_align = (pos - io_align) & ~PAGE_MASK; + page_align = (pos - io_align + buf_align) & ~PAGE_MASK; else page_align = pos & ~PAGE_MASK; this_len = left; @@ -376,16 +377,18 @@ static ssize_t ceph_sync_read(struct file *file, char __user *data, struct inode *inode = file->f_dentry->d_inode; struct page **pages; u64 off = *poff; - int num_pages = calc_pages_for(off, len); - int ret; + int num_pages, ret; dout("sync_read on file %p %llu~%u %s\n", file, off, len, (file->f_flags & O_DIRECT) ? "O_DIRECT" : ""); - if (file->f_flags & O_DIRECT) + if (file->f_flags & O_DIRECT) { + num_pages = calc_pages_for((unsigned long)data, len); pages = ceph_get_direct_page_vector(data, num_pages); - else + } else { + num_pages = calc_pages_for(off, len); pages = ceph_alloc_page_vector(num_pages, GFP_NOFS); + } if (IS_ERR(pages)) return PTR_ERR(pages); @@ -400,7 +403,8 @@ static ssize_t ceph_sync_read(struct file *file, char __user *data, goto done; ret = striped_read(inode, off, len, pages, num_pages, checkeof, - file->f_flags & O_DIRECT); + file->f_flags & O_DIRECT, + (unsigned long)data & ~PAGE_MASK); if (ret >= 0 && (file->f_flags & O_DIRECT) == 0) ret = ceph_copy_page_vector_to_user(pages, data, off, ret); @@ -456,6 +460,7 @@ static ssize_t ceph_sync_write(struct file *file, const char __user *data, int do_sync = 0; int check_caps = 0; int page_align, io_align; + unsigned long buf_align; int ret; struct timespec mtime = CURRENT_TIME; @@ -471,6 +476,7 @@ static ssize_t ceph_sync_write(struct file *file, const char __user *data, pos = *offset; io_align = pos & ~PAGE_MASK; + buf_align = (unsigned long)data & ~PAGE_MASK; ret = filemap_write_and_wait_range(inode->i_mapping, pos, pos + left); if (ret < 0) @@ -496,12 +502,15 @@ static ssize_t ceph_sync_write(struct file *file, const char __user *data, */ more: len = left; - if (file->f_flags & O_DIRECT) + if (file->f_flags & O_DIRECT) { /* write from beginning of first page, regardless of io alignment */ - page_align = (pos - io_align) & ~PAGE_MASK; - else + page_align = (pos - io_align + buf_align) & ~PAGE_MASK; + num_pages = calc_pages_for((unsigned long)data, len); + } else { page_align = pos & ~PAGE_MASK; + num_pages = calc_pages_for(pos, len); + } req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout, ceph_vino(inode), pos, &len, CEPH_OSD_OP_WRITE, flags, @@ -512,8 +521,6 @@ more: if (!req) return -ENOMEM; - num_pages = calc_pages_for(pos, len); - if (file->f_flags & O_DIRECT) { pages = ceph_get_direct_page_vector(data, num_pages); if (IS_ERR(pages)) { -- cgit v1.2.3