X-Git-Url: http://git.agner.ch/gitweb/?p=linux.git;a=blobdiff_plain;f=fs%2Fcifs%2Ffile.c;h=5bac2763c450514c0fcb887cce0c5fe36bce1fec;hp=53c15074bb3622b9a251bef0eafeed866a24ce0b;hb=19dfc1f5f2ef03a52aa30c8257c5745edef23f55;hpb=fe9ea91cde29125a3417890678f4d886cec4a71e diff --git a/fs/cifs/file.c b/fs/cifs/file.c index 53c15074bb36..5bac2763c450 100644 --- a/fs/cifs/file.c +++ b/fs/cifs/file.c @@ -2579,31 +2579,32 @@ cifs_writev(struct kiocb *iocb, const struct iovec *iov, struct cifsInodeInfo *cinode = CIFS_I(inode); struct TCP_Server_Info *server = tlink_tcon(cfile->tlink)->ses->server; ssize_t rc = -EACCES; - - BUG_ON(iocb->ki_pos != pos); + loff_t lock_pos = iocb->ki_pos; /* * We need to hold the sem to be sure nobody modifies lock list * with a brlock that prevents writing. */ down_read(&cinode->lock_sem); - if (!cifs_find_lock_conflict(cfile, pos, iov_length(iov, nr_segs), + mutex_lock(&inode->i_mutex); + if (file->f_flags & O_APPEND) + lock_pos = i_size_read(inode); + if (!cifs_find_lock_conflict(cfile, lock_pos, iov_length(iov, nr_segs), server->vals->exclusive_lock_type, NULL, CIFS_WRITE_OP)) { - mutex_lock(&inode->i_mutex); - rc = __generic_file_aio_write(iocb, iov, nr_segs, - &iocb->ki_pos); + rc = __generic_file_aio_write(iocb, iov, nr_segs); mutex_unlock(&inode->i_mutex); - } - if (rc > 0) { - ssize_t err; + if (rc > 0) { + ssize_t err; - err = generic_write_sync(file, iocb->ki_pos - rc, rc); - if (err < 0) - rc = err; + err = generic_write_sync(file, iocb->ki_pos - rc, rc); + if (rc < 0) + rc = err; + } + } else { + mutex_unlock(&inode->i_mutex); } - up_read(&cinode->lock_sem); return rc; } @@ -2739,56 +2740,27 @@ cifs_retry_async_readv(struct cifs_readdata *rdata) /** * cifs_readdata_to_iov - copy data from pages in response to an iovec * @rdata: the readdata response with list of pages holding data - * @iov: vector in which we should copy the data - * @nr_segs: number of segments in vector - * @offset: offset into file of the first iovec - * @copied: used to return the amount of data copied to the iov + * @iter: destination for our data * * This function copies data from a list of pages in a readdata response into * an array of iovecs. It will first calculate where the data should go * based on the info in the readdata and then copy the data into that spot. */ -static ssize_t -cifs_readdata_to_iov(struct cifs_readdata *rdata, const struct iovec *iov, - unsigned long nr_segs, loff_t offset, ssize_t *copied) +static int +cifs_readdata_to_iov(struct cifs_readdata *rdata, struct iov_iter *iter) { - int rc = 0; - struct iov_iter ii; - size_t pos = rdata->offset - offset; - ssize_t remaining = rdata->bytes; - unsigned char *pdata; + size_t remaining = rdata->bytes; unsigned int i; - /* set up iov_iter and advance to the correct offset */ - iov_iter_init(&ii, iov, nr_segs, iov_length(iov, nr_segs), 0); - iov_iter_advance(&ii, pos); - - *copied = 0; for (i = 0; i < rdata->nr_pages; i++) { - ssize_t copy; struct page *page = rdata->pages[i]; - - /* copy a whole page or whatever's left */ - copy = min_t(ssize_t, remaining, PAGE_SIZE); - - /* ...but limit it to whatever space is left in the iov */ - copy = min_t(ssize_t, copy, iov_iter_count(&ii)); - - /* go while there's data to be copied and no errors */ - if (copy && !rc) { - pdata = kmap(page); - rc = memcpy_toiovecend(ii.iov, pdata, ii.iov_offset, - (int)copy); - kunmap(page); - if (!rc) { - *copied += copy; - remaining -= copy; - iov_iter_advance(&ii, copy); - } - } + size_t copy = min(remaining, PAGE_SIZE); + size_t written = copy_page_to_iter(page, 0, copy, iter); + remaining -= written; + if (written < copy && iov_iter_count(iter) > 0) + break; } - - return rc; + return remaining ? -EFAULT : 0; } static void @@ -2849,20 +2821,21 @@ cifs_uncached_read_into_pages(struct TCP_Server_Info *server, return total_read > 0 ? total_read : result; } -static ssize_t -cifs_iovec_read(struct file *file, const struct iovec *iov, - unsigned long nr_segs, loff_t *poffset) +ssize_t cifs_user_readv(struct kiocb *iocb, const struct iovec *iov, + unsigned long nr_segs, loff_t pos) { + struct file *file = iocb->ki_filp; ssize_t rc; size_t len, cur_len; ssize_t total_read = 0; - loff_t offset = *poffset; + loff_t offset = pos; unsigned int npages; struct cifs_sb_info *cifs_sb; struct cifs_tcon *tcon; struct cifsFileInfo *open_file; struct cifs_readdata *rdata, *tmp; struct list_head rdata_list; + struct iov_iter to; pid_t pid; if (!nr_segs) @@ -2872,6 +2845,8 @@ cifs_iovec_read(struct file *file, const struct iovec *iov, if (!len) return 0; + iov_iter_init(&to, iov, nr_segs, len, 0); + INIT_LIST_HEAD(&rdata_list); cifs_sb = CIFS_SB(file->f_path.dentry->d_sb); open_file = file->private_data; @@ -2929,55 +2904,44 @@ error: if (!list_empty(&rdata_list)) rc = 0; + len = iov_iter_count(&to); /* the loop below should proceed in the order of increasing offsets */ -restart_loop: list_for_each_entry_safe(rdata, tmp, &rdata_list, list) { + again: if (!rc) { - ssize_t copied; - /* FIXME: freezable sleep too? */ rc = wait_for_completion_killable(&rdata->done); if (rc) rc = -EINTR; - else if (rdata->result) + else if (rdata->result) { rc = rdata->result; - else { - rc = cifs_readdata_to_iov(rdata, iov, - nr_segs, *poffset, - &copied); - total_read += copied; + /* resend call if it's a retryable error */ + if (rc == -EAGAIN) { + rc = cifs_retry_async_readv(rdata); + goto again; + } + } else { + rc = cifs_readdata_to_iov(rdata, &to); } - /* resend call if it's a retryable error */ - if (rc == -EAGAIN) { - rc = cifs_retry_async_readv(rdata); - goto restart_loop; - } } list_del_init(&rdata->list); kref_put(&rdata->refcount, cifs_uncached_readdata_release); } + total_read = len - iov_iter_count(&to); + cifs_stats_bytes_read(tcon, total_read); - *poffset += total_read; /* mask nodata case */ if (rc == -ENODATA) rc = 0; - return total_read ? total_read : rc; -} - -ssize_t cifs_user_readv(struct kiocb *iocb, const struct iovec *iov, - unsigned long nr_segs, loff_t pos) -{ - ssize_t read; - - read = cifs_iovec_read(iocb->ki_filp, iov, nr_segs, &pos); - if (read > 0) - iocb->ki_pos = pos; - - return read; + if (total_read) { + iocb->ki_pos = pos + total_read; + return total_read; + } + return rc; } ssize_t