* Set the byte-range lock (mandatory style). Returns:
* 1) 0, if we set the lock and don't need to request to the server;
* 2) 1, if no locks prevent us but we need to request to the server;
- * 3) -EACCESS, if there is a lock that prevents us and wait is false.
+ * 3) -EACCES, if there is a lock that prevents us and wait is false.
*/
static int
cifs_lock_add_if(struct cifsFileInfo *cfile, struct cifsLockInfo *lock,
return 0;
}
+static int
+cifs_resend_wdata(struct cifs_writedata *wdata, struct list_head *wdata_list,
+ struct cifs_aio_ctx *ctx)
+{
+ int wait_retry = 0;
+ unsigned int wsize, credits;
+ int rc;
+ struct TCP_Server_Info *server =
+ tlink_tcon(wdata->cfile->tlink)->ses->server;
+
+ /*
+ * Try to resend this wdata, waiting for credits up to 3 seconds.
+ * Note: we are attempting to resend the whole wdata not in segments
+ */
+ do {
+ rc = server->ops->wait_mtu_credits(
+ server, wdata->bytes, &wsize, &credits);
+
+ if (rc)
+ break;
+
+ if (wsize < wdata->bytes) {
+ add_credits_and_wake_if(server, credits, 0);
+ msleep(1000);
+ wait_retry++;
+ }
+ } while (wsize < wdata->bytes && wait_retry < 3);
+
+ if (wsize < wdata->bytes) {
+ rc = -EBUSY;
+ goto out;
+ }
+
+ rc = -EAGAIN;
+ while (rc == -EAGAIN) {
+ rc = 0;
+ if (wdata->cfile->invalidHandle)
+ rc = cifs_reopen_file(wdata->cfile, false);
+ if (!rc)
+ rc = server->ops->async_writev(wdata,
+ cifs_uncached_writedata_release);
+ }
+
+ if (!rc) {
+ list_add_tail(&wdata->list, wdata_list);
+ return 0;
+ }
+
+ add_credits_and_wake_if(server, wdata->credits, 0);
+out:
+ kref_put(&wdata->refcount, cifs_uncached_writedata_release);
+
+ return rc;
+}
+
static int
cifs_write_from_iter(loff_t offset, size_t len, struct iov_iter *from,
struct cifsFileInfo *open_file,
loff_t saved_offset = offset;
pid_t pid;
struct TCP_Server_Info *server;
+ struct page **pagevec;
+ size_t start;
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
pid = open_file->pid;
if (rc)
break;
- nr_pages = get_numpages(wsize, len, &cur_len);
- wdata = cifs_writedata_alloc(nr_pages,
+ if (ctx->direct_io) {
+ ssize_t result;
+
+ result = iov_iter_get_pages_alloc(
+ from, &pagevec, wsize, &start);
+ if (result < 0) {
+ cifs_dbg(VFS,
+ "direct_writev couldn't get user pages "
+ "(rc=%zd) iter type %d iov_offset %zd "
+ "count %zd\n",
+ result, from->type,
+ from->iov_offset, from->count);
+ dump_stack();
+ break;
+ }
+ cur_len = (size_t)result;
+ iov_iter_advance(from, cur_len);
+
+ nr_pages =
+ (cur_len + start + PAGE_SIZE - 1) / PAGE_SIZE;
+
+ wdata = cifs_writedata_direct_alloc(pagevec,
cifs_uncached_writev_complete);
- if (!wdata) {
- rc = -ENOMEM;
- add_credits_and_wake_if(server, credits, 0);
- break;
- }
+ if (!wdata) {
+ rc = -ENOMEM;
+ add_credits_and_wake_if(server, credits, 0);
+ break;
+ }
- rc = cifs_write_allocate_pages(wdata->pages, nr_pages);
- if (rc) {
- kfree(wdata);
- add_credits_and_wake_if(server, credits, 0);
- break;
- }
- num_pages = nr_pages;
- rc = wdata_fill_from_iovec(wdata, from, &cur_len, &num_pages);
- if (rc) {
- for (i = 0; i < nr_pages; i++)
- put_page(wdata->pages[i]);
- kfree(wdata);
- add_credits_and_wake_if(server, credits, 0);
- break;
- }
+ wdata->page_offset = start;
+ wdata->tailsz =
+ nr_pages > 1 ?
+ cur_len - (PAGE_SIZE - start) -
+ (nr_pages - 2) * PAGE_SIZE :
+ cur_len;
+ } else {
+ nr_pages = get_numpages(wsize, len, &cur_len);
+ wdata = cifs_writedata_alloc(nr_pages,
+ cifs_uncached_writev_complete);
+ if (!wdata) {
+ rc = -ENOMEM;
+ add_credits_and_wake_if(server, credits, 0);
+ break;
+ }
- /*
- * Bring nr_pages down to the number of pages we actually used,
- * and free any pages that we didn't use.
- */
- for ( ; nr_pages > num_pages; nr_pages--)
- put_page(wdata->pages[nr_pages - 1]);
+ rc = cifs_write_allocate_pages(wdata->pages, nr_pages);
+ if (rc) {
+ kfree(wdata);
+ add_credits_and_wake_if(server, credits, 0);
+ break;
+ }
+
+ num_pages = nr_pages;
+ rc = wdata_fill_from_iovec(
+ wdata, from, &cur_len, &num_pages);
+ if (rc) {
+ for (i = 0; i < nr_pages; i++)
+ put_page(wdata->pages[i]);
+ kfree(wdata);
+ add_credits_and_wake_if(server, credits, 0);
+ break;
+ }
+
+ /*
+ * Bring nr_pages down to the number of pages we
+ * actually used, and free any pages that we didn't use.
+ */
+ for ( ; nr_pages > num_pages; nr_pages--)
+ put_page(wdata->pages[nr_pages - 1]);
+
+ wdata->tailsz = cur_len - ((nr_pages - 1) * PAGE_SIZE);
+ }
wdata->sync_mode = WB_SYNC_ALL;
wdata->nr_pages = nr_pages;
wdata->pid = pid;
wdata->bytes = cur_len;
wdata->pagesz = PAGE_SIZE;
- wdata->tailsz = cur_len - ((nr_pages - 1) * PAGE_SIZE);
wdata->credits = credits;
wdata->ctx = ctx;
kref_get(&ctx->refcount);
INIT_LIST_HEAD(&tmp_list);
list_del_init(&wdata->list);
- iov_iter_advance(&tmp_from,
+ if (ctx->direct_io)
+ rc = cifs_resend_wdata(
+ wdata, &tmp_list, ctx);
+ else {
+ iov_iter_advance(&tmp_from,
wdata->offset - ctx->pos);
- rc = cifs_write_from_iter(wdata->offset,
+ rc = cifs_write_from_iter(wdata->offset,
wdata->bytes, &tmp_from,
ctx->cfile, cifs_sb, &tmp_list,
ctx);
+ }
list_splice(&tmp_list, &ctx->list);
kref_put(&wdata->refcount, cifs_uncached_writedata_release);
}
- for (i = 0; i < ctx->npages; i++)
- put_page(ctx->bv[i].bv_page);
+ if (!ctx->direct_io)
+ for (i = 0; i < ctx->npages; i++)
+ put_page(ctx->bv[i].bv_page);
cifs_stats_bytes_written(tcon, ctx->total_len);
set_bit(CIFS_INO_INVALID_MAPPING, &CIFS_I(dentry->d_inode)->flags);
complete(&ctx->done);
}
-ssize_t cifs_user_writev(struct kiocb *iocb, struct iov_iter *from)
+static ssize_t __cifs_writev(
+ struct kiocb *iocb, struct iov_iter *from, bool direct)
{
struct file *file = iocb->ki_filp;
ssize_t total_written = 0;
struct cifs_sb_info *cifs_sb;
struct cifs_aio_ctx *ctx;
struct iov_iter saved_from = *from;
+ size_t len = iov_iter_count(from);
int rc;
/*
- * BB - optimize the way when signing is disabled. We can drop this
- * extra memory-to-memory copying and use iovec buffers for constructing
- * write request.
+ * iov_iter_get_pages_alloc doesn't work with ITER_KVEC.
+ * In this case, fall back to non-direct write function.
+ * this could be improved by getting pages directly in ITER_KVEC
*/
+ if (direct && from->type & ITER_KVEC) {
+ cifs_dbg(FYI, "use non-direct cifs_writev for kvec I/O\n");
+ direct = false;
+ }
rc = generic_write_checks(iocb, from);
if (rc <= 0)
ctx->pos = iocb->ki_pos;
- rc = setup_aio_ctx_iter(ctx, from, WRITE);
- if (rc) {
- kref_put(&ctx->refcount, cifs_aio_ctx_release);
- return rc;
+ if (direct) {
+ ctx->direct_io = true;
+ ctx->iter = *from;
+ ctx->len = len;
+ } else {
+ rc = setup_aio_ctx_iter(ctx, from, WRITE);
+ if (rc) {
+ kref_put(&ctx->refcount, cifs_aio_ctx_release);
+ return rc;
+ }
}
/* grab a lock here due to read response handlers can access ctx */
return total_written;
}
+ssize_t cifs_direct_writev(struct kiocb *iocb, struct iov_iter *from)
+{
+ return __cifs_writev(iocb, from, true);
+}
+
+ssize_t cifs_user_writev(struct kiocb *iocb, struct iov_iter *from)
+{
+ return __cifs_writev(iocb, from, false);
+}
+
static ssize_t
cifs_writev(struct kiocb *iocb, struct iov_iter *from)
{
kref_put(&rdata->ctx->refcount, cifs_aio_ctx_release);
for (i = 0; i < rdata->nr_pages; i++) {
put_page(rdata->pages[i]);
- rdata->pages[i] = NULL;
}
cifs_readdata_release(refcount);
}
return uncached_fill_pages(server, rdata, iter, iter->count);
}
+static int cifs_resend_rdata(struct cifs_readdata *rdata,
+ struct list_head *rdata_list,
+ struct cifs_aio_ctx *ctx)
+{
+ int wait_retry = 0;
+ unsigned int rsize, credits;
+ int rc;
+ struct TCP_Server_Info *server =
+ tlink_tcon(rdata->cfile->tlink)->ses->server;
+
+ /*
+ * Try to resend this rdata, waiting for credits up to 3 seconds.
+ * Note: we are attempting to resend the whole rdata not in segments
+ */
+ do {
+ rc = server->ops->wait_mtu_credits(server, rdata->bytes,
+ &rsize, &credits);
+
+ if (rc)
+ break;
+
+ if (rsize < rdata->bytes) {
+ add_credits_and_wake_if(server, credits, 0);
+ msleep(1000);
+ wait_retry++;
+ }
+ } while (rsize < rdata->bytes && wait_retry < 3);
+
+ /*
+ * If we can't find enough credits to send this rdata
+ * release the rdata and return failure, this will pass
+ * whatever I/O amount we have finished to VFS.
+ */
+ if (rsize < rdata->bytes) {
+ rc = -EBUSY;
+ goto out;
+ }
+
+ rc = -EAGAIN;
+ while (rc == -EAGAIN) {
+ rc = 0;
+ if (rdata->cfile->invalidHandle)
+ rc = cifs_reopen_file(rdata->cfile, true);
+ if (!rc)
+ rc = server->ops->async_readv(rdata);
+ }
+
+ if (!rc) {
+ /* Add to aio pending list */
+ list_add_tail(&rdata->list, rdata_list);
+ return 0;
+ }
+
+ add_credits_and_wake_if(server, rdata->credits, 0);
+out:
+ kref_put(&rdata->refcount,
+ cifs_uncached_readdata_release);
+
+ return rc;
+}
+
static int
cifs_send_async_read(loff_t offset, size_t len, struct cifsFileInfo *open_file,
struct cifs_sb_info *cifs_sb, struct list_head *rdata_list,
int rc;
pid_t pid;
struct TCP_Server_Info *server;
+ struct page **pagevec;
+ size_t start;
+ struct iov_iter direct_iov = ctx->iter;
server = tlink_tcon(open_file->tlink)->ses->server;
else
pid = current->tgid;
+ if (ctx->direct_io)
+ iov_iter_advance(&direct_iov, offset - ctx->pos);
+
do {
rc = server->ops->wait_mtu_credits(server, cifs_sb->rsize,
&rsize, &credits);
break;
cur_len = min_t(const size_t, len, rsize);
- npages = DIV_ROUND_UP(cur_len, PAGE_SIZE);
- /* allocate a readdata struct */
- rdata = cifs_readdata_alloc(npages,
+ if (ctx->direct_io) {
+ ssize_t result;
+
+ result = iov_iter_get_pages_alloc(
+ &direct_iov, &pagevec,
+ cur_len, &start);
+ if (result < 0) {
+ cifs_dbg(VFS,
+ "couldn't get user pages (cur_len=%zd)"
+ " iter type %d"
+ " iov_offset %zd count %zd\n",
+ result, direct_iov.type,
+ direct_iov.iov_offset,
+ direct_iov.count);
+ dump_stack();
+ break;
+ }
+ cur_len = (size_t)result;
+ iov_iter_advance(&direct_iov, cur_len);
+
+ rdata = cifs_readdata_direct_alloc(
+ pagevec, cifs_uncached_readv_complete);
+ if (!rdata) {
+ add_credits_and_wake_if(server, credits, 0);
+ rc = -ENOMEM;
+ break;
+ }
+
+ npages = (cur_len + start + PAGE_SIZE-1) / PAGE_SIZE;
+ rdata->page_offset = start;
+ rdata->tailsz = npages > 1 ?
+ cur_len-(PAGE_SIZE-start)-(npages-2)*PAGE_SIZE :
+ cur_len;
+
+ } else {
+
+ npages = DIV_ROUND_UP(cur_len, PAGE_SIZE);
+ /* allocate a readdata struct */
+ rdata = cifs_readdata_alloc(npages,
cifs_uncached_readv_complete);
- if (!rdata) {
- add_credits_and_wake_if(server, credits, 0);
- rc = -ENOMEM;
- break;
- }
+ if (!rdata) {
+ add_credits_and_wake_if(server, credits, 0);
+ rc = -ENOMEM;
+ break;
+ }
- rc = cifs_read_allocate_pages(rdata, npages);
- if (rc)
- goto error;
+ rc = cifs_read_allocate_pages(rdata, npages);
+ if (rc)
+ goto error;
+
+ rdata->tailsz = PAGE_SIZE;
+ }
rdata->cfile = cifsFileInfo_get(open_file);
rdata->nr_pages = npages;
rdata->bytes = cur_len;
rdata->pid = pid;
rdata->pagesz = PAGE_SIZE;
- rdata->tailsz = PAGE_SIZE;
rdata->read_into_pages = cifs_uncached_read_into_pages;
rdata->copy_into_pages = cifs_uncached_copy_into_pages;
rdata->credits = credits;
if (rc) {
add_credits_and_wake_if(server, rdata->credits, 0);
kref_put(&rdata->refcount,
- cifs_uncached_readdata_release);
- if (rc == -EAGAIN)
+ cifs_uncached_readdata_release);
+ if (rc == -EAGAIN) {
+ iov_iter_revert(&direct_iov, cur_len);
continue;
+ }
break;
}
* reading.
*/
if (got_bytes && got_bytes < rdata->bytes) {
- rc = cifs_readdata_to_iov(rdata, to);
+ rc = 0;
+ if (!ctx->direct_io)
+ rc = cifs_readdata_to_iov(rdata, to);
if (rc) {
kref_put(&rdata->refcount,
- cifs_uncached_readdata_release);
+ cifs_uncached_readdata_release);
continue;
}
}
- rc = cifs_send_async_read(
+ if (ctx->direct_io) {
+ /*
+ * Re-use rdata as this is a
+ * direct I/O
+ */
+ rc = cifs_resend_rdata(
+ rdata,
+ &tmp_list, ctx);
+ } else {
+ rc = cifs_send_async_read(
rdata->offset + got_bytes,
rdata->bytes - got_bytes,
rdata->cfile, cifs_sb,
&tmp_list, ctx);
+ kref_put(&rdata->refcount,
+ cifs_uncached_readdata_release);
+ }
+
list_splice(&tmp_list, &ctx->list);
- kref_put(&rdata->refcount,
- cifs_uncached_readdata_release);
goto again;
} else if (rdata->result)
rc = rdata->result;
- else
+ else if (!ctx->direct_io)
rc = cifs_readdata_to_iov(rdata, to);
/* if there was a short read -- discard anything left */
if (rdata->got_bytes && rdata->got_bytes < rdata->bytes)
rc = -ENODATA;
+
+ ctx->total_len += rdata->got_bytes;
}
list_del_init(&rdata->list);
kref_put(&rdata->refcount, cifs_uncached_readdata_release);
}
- for (i = 0; i < ctx->npages; i++) {
- if (ctx->should_dirty)
- set_page_dirty(ctx->bv[i].bv_page);
- put_page(ctx->bv[i].bv_page);
- }
+ if (!ctx->direct_io) {
+ for (i = 0; i < ctx->npages; i++) {
+ if (ctx->should_dirty)
+ set_page_dirty(ctx->bv[i].bv_page);
+ put_page(ctx->bv[i].bv_page);
+ }
- ctx->total_len = ctx->len - iov_iter_count(to);
+ ctx->total_len = ctx->len - iov_iter_count(to);
+ }
cifs_stats_bytes_read(tcon, ctx->total_len);
complete(&ctx->done);
}
-ssize_t cifs_user_readv(struct kiocb *iocb, struct iov_iter *to)
+static ssize_t __cifs_readv(
+ struct kiocb *iocb, struct iov_iter *to, bool direct)
{
- struct file *file = iocb->ki_filp;
- ssize_t rc;
size_t len;
- ssize_t total_read = 0;
- loff_t offset = iocb->ki_pos;
+ struct file *file = iocb->ki_filp;
struct cifs_sb_info *cifs_sb;
- struct cifs_tcon *tcon;
struct cifsFileInfo *cfile;
+ struct cifs_tcon *tcon;
+ ssize_t rc, total_read = 0;
+ loff_t offset = iocb->ki_pos;
struct cifs_aio_ctx *ctx;
+ /*
+ * iov_iter_get_pages_alloc() doesn't work with ITER_KVEC,
+ * fall back to data copy read path
+ * this could be improved by getting pages directly in ITER_KVEC
+ */
+ if (direct && to->type & ITER_KVEC) {
+ cifs_dbg(FYI, "use non-direct cifs_user_readv for kvec I/O\n");
+ direct = false;
+ }
+
len = iov_iter_count(to);
if (!len)
return 0;
if (iter_is_iovec(to))
ctx->should_dirty = true;
- rc = setup_aio_ctx_iter(ctx, to, READ);
- if (rc) {
- kref_put(&ctx->refcount, cifs_aio_ctx_release);
- return rc;
+ if (direct) {
+ ctx->pos = offset;
+ ctx->direct_io = true;
+ ctx->iter = *to;
+ ctx->len = len;
+ } else {
+ rc = setup_aio_ctx_iter(ctx, to, READ);
+ if (rc) {
+ kref_put(&ctx->refcount, cifs_aio_ctx_release);
+ return rc;
+ }
+ len = ctx->len;
}
- len = ctx->len;
-
/* grab a lock here due to read response handlers can access ctx */
mutex_lock(&ctx->aio_mutex);
return rc;
}
+ssize_t cifs_direct_readv(struct kiocb *iocb, struct iov_iter *to)
+{
+ return __cifs_readv(iocb, to, true);
+}
+
+ssize_t cifs_user_readv(struct kiocb *iocb, struct iov_iter *to)
+{
+ return __cifs_readv(iocb, to, false);
+}
+
ssize_t
cifs_strict_readv(struct kiocb *iocb, struct iov_iter *to)
{
git.samba.org / sfrench / cifs-2.6.git / blobdiff