2012/2/3 Jeff Layton <jlayton@xxxxxxxxxx>:
> Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>
> ---
> fs/cifs/cifsproto.h | 2 +
> fs/cifs/cifssmb.c | 4 +-
> fs/cifs/file.c | 191 ++++++++++++++++++++++++++++++++-------------------
> 3 files changed, 126 insertions(+), 71 deletions(-)
>
> diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h
> index bceadc5..a131ded 100644
> --- a/fs/cifs/cifsproto.h
> +++ b/fs/cifs/cifsproto.h
> @@ -473,6 +473,8 @@ int cifs_async_readv(struct cifs_readdata *rdata);
> /* asynchronous write support */
> struct cifs_writedata {
> struct kref refcount;
> + struct list_head list;
> + struct completion done;
> enum writeback_sync_modes sync_mode;
> struct work_struct work;
> struct cifsFileInfo *cfile;
> diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
> index 113b5af..6e93c9e 100644
> --- a/fs/cifs/cifssmb.c
> +++ b/fs/cifs/cifssmb.c
> @@ -2034,8 +2034,10 @@ cifs_writedata_alloc(unsigned int nr_pages, work_func_t complete)
> wdata = kzalloc(sizeof(*wdata) +
> sizeof(struct page *) * (nr_pages - 1), GFP_NOFS);
> if (wdata != NULL) {
> - INIT_WORK(&wdata->work, complete);
> kref_init(&wdata->refcount);
> + INIT_LIST_HEAD(&wdata->list);
> + init_completion(&wdata->done);
> + INIT_WORK(&wdata->work, complete);
> }
> return wdata;
> }
> diff --git a/fs/cifs/file.c b/fs/cifs/file.c
> index c7e47a2..ef25fc5 100644
> --- a/fs/cifs/file.c
> +++ b/fs/cifs/file.c
> @@ -2057,23 +2057,55 @@ size_t get_numpages(const size_t wsize, const size_t len, size_t *cur_len)
> return num_pages;
> }
>
> +static void
> +cifs_uncached_marshal_iov(struct kvec *iov, struct cifs_writedata *wdata)
> +{
> + int i;
> + size_t bytes = wdata->bytes;
> +
> + /* marshal up the pages into iov array */
> + for (i = 0; i < wdata->nr_pages; i++) {
> + iov[i + 1].iov_len = min(bytes, PAGE_SIZE);
> + iov[i + 1].iov_base = kmap(wdata->pages[i]);
> + bytes -= iov[i + 1].iov_len;
> + }
> +}
> +
> +static void
> +cifs_uncached_writev_complete(struct work_struct *work)
> +{
> + int i;
> + struct cifs_writedata *wdata = container_of(work,
> + struct cifs_writedata, work);
> +
> + complete(&wdata->done);
> +
> + if (wdata->result != -EAGAIN) {
> + for (i = 0; i < wdata->nr_pages; i++)
> + put_page(wdata->pages[i]);
> + }
> +
> + kref_put(&wdata->refcount, cifs_writedata_release);
> +}
> +
> static ssize_t
> cifs_iovec_write(struct file *file, const struct iovec *iov,
> unsigned long nr_segs, loff_t *poffset)
> {
> - unsigned int written;
> - unsigned long num_pages, npages, i;
> + unsigned long nr_pages, i;
> size_t copied, len, cur_len;
> ssize_t total_written = 0;
> - struct kvec *to_send;
> - struct page **pages;
> + loff_t offset = *poffset;
> struct iov_iter it;
> - struct inode *inode;
> + struct inode *inode = file->f_path.dentry->d_inode;
> + struct cifsInodeInfo *cifsi = CIFS_I(inode);
> struct cifsFileInfo *open_file;
> struct cifs_tcon *tcon;
> struct cifs_sb_info *cifs_sb;
> - int xid, rc;
> - __u32 pid;
> + struct cifs_writedata *wdata, *tmp;
> + struct list_head wdata_list;
> + int rc;
> + pid_t pid;
>
> len = iov_length(iov, nr_segs);
> if (!len)
> @@ -2083,103 +2115,122 @@ cifs_iovec_write(struct file *file, const struct iovec *iov,
> if (rc)
> return rc;
>
> + INIT_LIST_HEAD(&wdata_list);
> cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
> - num_pages = get_numpages(cifs_sb->wsize, len, &cur_len);
> -
> - pages = kmalloc(sizeof(struct pages *)*num_pages, GFP_KERNEL);
> - if (!pages)
> - return -ENOMEM;
> -
> - to_send = kmalloc(sizeof(struct kvec)*(num_pages + 1), GFP_KERNEL);
> - if (!to_send) {
> - kfree(pages);
> - return -ENOMEM;
> - }
> -
> - rc = cifs_write_allocate_pages(pages, num_pages);
> - if (rc) {
> - kfree(pages);
> - kfree(to_send);
> - return rc;
> - }
> -
> - xid = GetXid();
> open_file = file->private_data;
> + tcon = tlink_tcon(open_file->tlink);
>
> if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
> pid = open_file->pid;
> else
> pid = current->tgid;
>
> - tcon = tlink_tcon(open_file->tlink);
> - inode = file->f_path.dentry->d_inode;
> -
> iov_iter_init(&it, iov, nr_segs, len, 0);
> - npages = num_pages;
> -
> do {
> - size_t save_len = cur_len;
> - for (i = 0; i < npages; i++) {
> - copied = min_t(const size_t, cur_len, PAGE_CACHE_SIZE);
> - copied = iov_iter_copy_from_user(pages[i], &it, 0,
> - copied);
> + size_t save_len;
> +
> + nr_pages = get_numpages(cifs_sb->wsize, len, &cur_len);
> + wdata = cifs_writedata_alloc(nr_pages,
> + cifs_uncached_writev_complete);
> + if (!wdata) {
> + rc = -ENOMEM;
> + break;
> + }
> +
> + rc = cifs_write_allocate_pages(wdata->pages, nr_pages);
> + if (rc) {
> + kfree(wdata);
> + break;
> + }
> +
> + save_len = cur_len;
> + for (i = 0; i < nr_pages; i++) {
> + copied = min_t(const size_t, cur_len, PAGE_SIZE);
> + copied = iov_iter_copy_from_user(wdata->pages[i], &it,
> + 0, copied);
> cur_len -= copied;
> iov_iter_advance(&it, copied);
> - to_send[i+1].iov_base = kmap(pages[i]);
> - to_send[i+1].iov_len = copied;
> }
> -
> cur_len = save_len - cur_len;
>
> + wdata->sync_mode = WB_SYNC_ALL;
> + wdata->nr_pages = nr_pages;
> + wdata->offset = (__u64)offset;
> + wdata->cfile = cifsFileInfo_get(open_file);
> + wdata->pid = pid;
> + wdata->bytes = cur_len;
> + wdata->marshal_iov = cifs_uncached_marshal_iov;
> do {
> if (open_file->invalidHandle) {
> rc = cifs_reopen_file(open_file, false);
> if (rc != 0)
> break;
> }
When we reopen a file, we do it with the current pid, but in
cfile->pid leaves with the old value (and pid variable too).Should we
do reopen with cfile->pid to save the original state of the file (now
we don't restore locks, if we do it - it will be the problem)?
> - io_parms.netfid = open_file->netfid;
> - io_parms.pid = pid;
> - io_parms.tcon = tcon;
> - io_parms.offset = *poffset;
> - io_parms.length = cur_len;
> - rc = CIFSSMBWrite2(xid, &io_parms, &written, to_send,
> - npages, 0);
> + rc = cifs_async_writev(wdata);
> } while (rc == -EAGAIN);
>
> - for (i = 0; i < npages; i++)
> - kunmap(pages[i]);
> -
> - if (written) {
> - len -= written;
> - total_written += written;
> - cifs_update_eof(CIFS_I(inode), *poffset, written);
> - *poffset += written;
> - } else if (rc < 0) {
> - if (!total_written)
> - total_written = rc;
> + if (rc) {
> + kref_put(&wdata->refcount, cifs_writedata_release);
> break;
> }
>
> - /* get length and number of kvecs of the next write */
> - npages = get_numpages(cifs_sb->wsize, len, &cur_len);
> + list_add_tail(&wdata->list, &wdata_list);
> + offset += cur_len;
> + len -= cur_len;
> } while (len > 0);
>
> + /*
> + * If at least one write was successfully sent, then discard any rc
> + * value from the later writes. If the other write succeeds, then
> + * we'll end up returning whatever was written. If it fails, then
> + * we'll get a new rc value from that.
> + */
> + if (!list_empty(&wdata_list))
> + rc = 0;
> +
> + /*
> + * Wait for and collect replies for any successful sends in order of
> + * increasing offset. Once an error is hit or we get a fatal signal
> + * while waiting, then return without waiting for any more replies.
> + */
> +restart_loop:
> + list_for_each_entry_safe(wdata, tmp, &wdata_list, list) {
> + if (!rc) {
> + /* FIXME: freezable too? */
> + rc = wait_for_completion_killable(&wdata->done);
> + if (!rc) {
> + if (wdata->result)
> + rc = wdata->result;
> + else
> + total_written += wdata->bytes;
> + } else if (rc == -EAGAIN) {
> + do {
> + if (open_file->invalidHandle) {
> + rc = cifs_reopen_file(open_file,
> + false);
> + if (rc != 0)
> + break;
> + }
> + rc = cifs_async_writev(wdata);
> + } while (rc == -EAGAIN);
> + goto restart_loop;
> + }
> + }
> + list_del_init(&wdata->list);
> + kref_put(&wdata->refcount, cifs_writedata_release);
> + }
> +
> if (total_written > 0) {
> + cifs_update_eof(cifsi, *poffset, total_written);
> + *poffset += total_written;
> spin_lock(&inode->i_lock);
> - if (*poffset > inode->i_size)
> - i_size_write(inode, *poffset);
> + if (offset > inode->i_size)
> + i_size_write(inode, cifsi->server_eof);
> spin_unlock(&inode->i_lock);
> }
>
> cifs_stats_bytes_written(tcon, total_written);
> - mark_inode_dirty_sync(inode);
> -
> - for (i = 0; i < num_pages; i++)
> - put_page(pages[i]);
> - kfree(to_send);
> - kfree(pages);
> - FreeXid(xid);
> - return total_written;
> + return total_written ? total_written : (ssize_t)rc;
> }
>
> ssize_t cifs_user_writev(struct kiocb *iocb, const struct iovec *iov,
> --
> 1.7.7.6
>
The patch itself looks correct.
Reviewed-by: Pavel Shilovsky <piastry@xxxxxxxxxxx>
--
Best regards,
Pavel Shilovsky.
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