* [PATCH v2 1/3] cifs: Use netfslib
2022-01-06 21:31 [RFC][PATCH v2 0/3] cifs: In-progress conversion to use iov_iters instead of page lists David Howells
@ 2022-01-06 21:32 ` David Howells
2022-01-06 21:32 ` [PATCH v2 2/3] cifs: Reverse the way iov_iters are used in reading David Howells
2022-01-06 21:32 ` [PATCH v2 3/3] cifs: Eliminate pages list from cifs_readdata, cifs_writedata and smb_rqst David Howells
2 siblings, 0 replies; 8+ messages in thread
From: David Howells @ 2022-01-06 21:32 UTC (permalink / raw)
To: smfrench; +Cc: nspmangalore, dhowells, jlayton, linux-cifs, linux-cachefs
---
fs/cifs/Kconfig | 1
fs/cifs/cifsglob.h | 2
fs/cifs/cifsproto.h | 3
fs/cifs/cifssmb.c | 16 +
fs/cifs/connect.c | 18 +-
fs/cifs/file.c | 582 ++++++++++++++-------------------------------------
fs/cifs/fscache.c | 35 ---
fs/cifs/fscache.h | 52 -----
fs/cifs/smb2pdu.c | 10 +
9 files changed, 201 insertions(+), 518 deletions(-)
diff --git a/fs/cifs/Kconfig b/fs/cifs/Kconfig
index 3b7e3b9e4fd2..c47e2d3a101f 100644
--- a/fs/cifs/Kconfig
+++ b/fs/cifs/Kconfig
@@ -2,6 +2,7 @@
config CIFS
tristate "SMB3 and CIFS support (advanced network filesystem)"
depends on INET
+ select NETFS_SUPPORT
select NLS
select CRYPTO
select CRYPTO_MD5
diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index ba6fbb1ad8f3..a5edae959f60 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -1320,6 +1320,7 @@ struct cifs_aio_ctx {
/* asynchronous read support */
struct cifs_readdata {
+ struct netfs_read_subrequest *subreq;
struct kref refcount;
struct list_head list;
struct completion done;
@@ -1338,6 +1339,7 @@ struct cifs_readdata {
int (*copy_into_pages)(struct TCP_Server_Info *server,
struct cifs_readdata *rdata,
struct iov_iter *iter);
+ struct iov_iter iter;
struct kvec iov[2];
struct TCP_Server_Info *server;
#ifdef CONFIG_CIFS_SMB_DIRECT
diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h
index 4f5a3e857df4..99c239dca807 100644
--- a/fs/cifs/cifsproto.h
+++ b/fs/cifs/cifsproto.h
@@ -237,6 +237,9 @@ extern int cifs_read_page_from_socket(struct TCP_Server_Info *server,
unsigned int page_offset,
unsigned int to_read);
extern int cifs_setup_cifs_sb(struct cifs_sb_info *cifs_sb);
+extern int cifs_read_iter_from_socket(struct TCP_Server_Info *server,
+ struct iov_iter *iter,
+ unsigned int to_read);
extern int cifs_match_super(struct super_block *, void *);
extern int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx);
extern void cifs_umount(struct cifs_sb_info *);
diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
index 243d17696f06..e068e3bda304 100644
--- a/fs/cifs/cifssmb.c
+++ b/fs/cifs/cifssmb.c
@@ -23,6 +23,7 @@
#include <linux/swap.h>
#include <linux/task_io_accounting_ops.h>
#include <linux/uaccess.h>
+#include <linux/netfs.h>
#include "cifspdu.h"
#include "cifsglob.h"
#include "cifsacl.h"
@@ -1332,11 +1333,11 @@ int
cifs_discard_remaining_data(struct TCP_Server_Info *server)
{
unsigned int rfclen = server->pdu_size;
- int remaining = rfclen + server->vals->header_preamble_size -
+ size_t remaining = rfclen + server->vals->header_preamble_size -
server->total_read;
while (remaining > 0) {
- int length;
+ ssize_t length;
length = cifs_discard_from_socket(server,
min_t(size_t, remaining,
@@ -1551,7 +1552,15 @@ cifs_readv_callback(struct mid_q_entry *mid)
rdata->result = -EIO;
}
- queue_work(cifsiod_wq, &rdata->work);
+ if (rdata->subreq) {
+ netfs_subreq_terminated(rdata->subreq,
+ (rdata->result == 0 || rdata->result == -EAGAIN) ?
+ rdata->got_bytes : rdata->result,
+ false);
+ kref_put(&rdata->refcount, cifs_readdata_release);
+ } else {
+ queue_work(cifsiod_wq, &rdata->work);
+ }
DeleteMidQEntry(mid);
add_credits(server, &credits, 0);
}
@@ -1996,7 +2005,6 @@ cifs_writev_complete(struct work_struct *work)
else if (wdata->result < 0)
SetPageError(page);
end_page_writeback(page);
- cifs_readpage_to_fscache(inode, page);
put_page(page);
}
if (wdata->result != -EAGAIN)
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index a52fd3a30c88..f6a145301e34 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -162,7 +162,7 @@ static void cifs_resolve_server(struct work_struct *work)
mutex_unlock(&server->srv_mutex);
}
-/**
+/*
* Mark all sessions and tcons for reconnect.
*
* @server needs to be previously set to CifsNeedReconnect.
@@ -656,6 +656,22 @@ cifs_read_page_from_socket(struct TCP_Server_Info *server, struct page *page,
return cifs_readv_from_socket(server, &smb_msg);
}
+int
+cifs_read_iter_from_socket(struct TCP_Server_Info *server, struct iov_iter *iter,
+ unsigned int to_read)
+{
+ struct msghdr smb_msg;
+ int ret;
+
+ smb_msg.msg_iter = *iter;
+ if (smb_msg.msg_iter.count > to_read)
+ smb_msg.msg_iter.count = to_read;
+ ret = cifs_readv_from_socket(server, &smb_msg);
+ if (ret > 0)
+ iov_iter_advance(iter, ret);
+ return ret;
+}
+
static bool
is_smb_response(struct TCP_Server_Info *server, unsigned char type)
{
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index d872f6fe8e7d..a3b9c0ecf02c 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -21,6 +21,7 @@
#include <linux/slab.h>
#include <linux/swap.h>
#include <linux/mm.h>
+#include <linux/netfs.h>
#include <asm/div64.h>
#include "cifsfs.h"
#include "cifspdu.h"
@@ -2614,6 +2615,7 @@ static int cifs_write_end(struct file *file, struct address_space *mapping,
struct inode *inode = mapping->host;
struct cifsFileInfo *cfile = file->private_data;
struct cifs_sb_info *cifs_sb = CIFS_SB(cfile->dentry->d_sb);
+ struct folio *folio = page_folio(page);
__u32 pid;
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
@@ -2624,14 +2626,14 @@ static int cifs_write_end(struct file *file, struct address_space *mapping,
cifs_dbg(FYI, "write_end for page %p from pos %lld with %d bytes\n",
page, pos, copied);
- if (PageChecked(page)) {
+ if (folio_test_checked(folio)) {
if (copied == len)
- SetPageUptodate(page);
- ClearPageChecked(page);
- } else if (!PageUptodate(page) && copied == PAGE_SIZE)
- SetPageUptodate(page);
+ folio_mark_uptodate(folio);
+ folio_clear_checked(folio);
+ } else if (!folio_test_uptodate(folio) && copied == PAGE_SIZE)
+ folio_mark_uptodate(folio);
- if (!PageUptodate(page)) {
+ if (!folio_test_uptodate(folio)) {
char *page_data;
unsigned offset = pos & (PAGE_SIZE - 1);
unsigned int xid;
@@ -4110,98 +4112,6 @@ cifs_strict_readv(struct kiocb *iocb, struct iov_iter *to)
return rc;
}
-static ssize_t
-cifs_read(struct file *file, char *read_data, size_t read_size, loff_t *offset)
-{
- int rc = -EACCES;
- unsigned int bytes_read = 0;
- unsigned int total_read;
- unsigned int current_read_size;
- unsigned int rsize;
- struct cifs_sb_info *cifs_sb;
- struct cifs_tcon *tcon;
- struct TCP_Server_Info *server;
- unsigned int xid;
- char *cur_offset;
- struct cifsFileInfo *open_file;
- struct cifs_io_parms io_parms = {0};
- int buf_type = CIFS_NO_BUFFER;
- __u32 pid;
-
- xid = get_xid();
- cifs_sb = CIFS_FILE_SB(file);
-
- /* FIXME: set up handlers for larger reads and/or convert to async */
- rsize = min_t(unsigned int, cifs_sb->ctx->rsize, CIFSMaxBufSize);
-
- if (file->private_data == NULL) {
- rc = -EBADF;
- free_xid(xid);
- return rc;
- }
- open_file = file->private_data;
- tcon = tlink_tcon(open_file->tlink);
- server = cifs_pick_channel(tcon->ses);
-
- if (!server->ops->sync_read) {
- free_xid(xid);
- return -ENOSYS;
- }
-
- if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
- pid = open_file->pid;
- else
- pid = current->tgid;
-
- if ((file->f_flags & O_ACCMODE) == O_WRONLY)
- cifs_dbg(FYI, "attempting read on write only file instance\n");
-
- for (total_read = 0, cur_offset = read_data; read_size > total_read;
- total_read += bytes_read, cur_offset += bytes_read) {
- do {
- current_read_size = min_t(uint, read_size - total_read,
- rsize);
- /*
- * For windows me and 9x we do not want to request more
- * than it negotiated since it will refuse the read
- * then.
- */
- if (!(tcon->ses->capabilities &
- tcon->ses->server->vals->cap_large_files)) {
- current_read_size = min_t(uint,
- current_read_size, CIFSMaxBufSize);
- }
- if (open_file->invalidHandle) {
- rc = cifs_reopen_file(open_file, true);
- if (rc != 0)
- break;
- }
- io_parms.pid = pid;
- io_parms.tcon = tcon;
- io_parms.offset = *offset;
- io_parms.length = current_read_size;
- io_parms.server = server;
- rc = server->ops->sync_read(xid, &open_file->fid, &io_parms,
- &bytes_read, &cur_offset,
- &buf_type);
- } while (rc == -EAGAIN);
-
- if (rc || (bytes_read == 0)) {
- if (total_read) {
- break;
- } else {
- free_xid(xid);
- return rc;
- }
- } else {
- cifs_stats_bytes_read(tcon, total_read);
- *offset += bytes_read;
- }
- }
- free_xid(xid);
- return total_read;
-}
-
/*
* If the page is mmap'ed into a process' page tables, then we need to make
* sure that it doesn't change while being written back.
@@ -4211,13 +4121,19 @@ cifs_page_mkwrite(struct vm_fault *vmf)
{
struct page *page = vmf->page;
+ /* Wait for the page to be written to the cache before we allow it to
+ * be modified. We then assume the entire page will need writing back.
+ */
#ifdef CONFIG_CIFS_FSCACHE
if (PageFsCache(page) &&
wait_on_page_fscache_killable(page) < 0)
return VM_FAULT_RETRY;
#endif
- lock_page(page);
+ wait_on_page_writeback(page);
+
+ if (lock_page_killable(page) < 0)
+ return VM_FAULT_RETRY;
return VM_FAULT_LOCKED;
}
@@ -4264,40 +4180,6 @@ int cifs_file_mmap(struct file *file, struct vm_area_struct *vma)
return rc;
}
-static void
-cifs_readv_complete(struct work_struct *work)
-{
- unsigned int i, got_bytes;
- struct cifs_readdata *rdata = container_of(work,
- struct cifs_readdata, work);
-
- got_bytes = rdata->got_bytes;
- for (i = 0; i < rdata->nr_pages; i++) {
- struct page *page = rdata->pages[i];
-
- lru_cache_add(page);
-
- if (rdata->result == 0 ||
- (rdata->result == -EAGAIN && got_bytes)) {
- flush_dcache_page(page);
- SetPageUptodate(page);
- } else
- SetPageError(page);
-
- unlock_page(page);
-
- if (rdata->result == 0 ||
- (rdata->result == -EAGAIN && got_bytes))
- cifs_readpage_to_fscache(rdata->mapping->host, page);
-
- got_bytes -= min_t(unsigned int, PAGE_SIZE, got_bytes);
-
- put_page(page);
- rdata->pages[i] = NULL;
- }
- kref_put(&rdata->refcount, cifs_readdata_release);
-}
-
static int
readpages_fill_pages(struct TCP_Server_Info *server,
struct cifs_readdata *rdata, struct iov_iter *iter,
@@ -4372,8 +4254,7 @@ readpages_fill_pages(struct TCP_Server_Info *server,
result = n;
#endif
else
- result = cifs_read_page_from_socket(
- server, page, page_offset, n);
+ result = cifs_read_iter_from_socket(server, &rdata->iter, n);
if (result < 0)
break;
@@ -4388,7 +4269,12 @@ static int
cifs_readpages_read_into_pages(struct TCP_Server_Info *server,
struct cifs_readdata *rdata, unsigned int len)
{
- return readpages_fill_pages(server, rdata, NULL, len);
+ int rc;
+
+ rc = cifs_read_iter_from_socket(server, &rdata->iter, len);
+ if (rc > 0)
+ rdata->got_bytes += rc;
+ return rc;
}
static int
@@ -4396,292 +4282,158 @@ cifs_readpages_copy_into_pages(struct TCP_Server_Info *server,
struct cifs_readdata *rdata,
struct iov_iter *iter)
{
+ printk("cifs_readpages_copy_into_pages\n");
return readpages_fill_pages(server, rdata, iter, iter->count);
}
-static int
-readpages_get_pages(struct address_space *mapping, struct list_head *page_list,
- unsigned int rsize, struct list_head *tmplist,
- unsigned int *nr_pages, loff_t *offset, unsigned int *bytes)
-{
- struct page *page, *tpage;
- unsigned int expected_index;
- int rc;
- gfp_t gfp = readahead_gfp_mask(mapping);
-
- INIT_LIST_HEAD(tmplist);
-
- page = lru_to_page(page_list);
-
- /*
- * Lock the page and put it in the cache. Since no one else
- * should have access to this page, we're safe to simply set
- * PG_locked without checking it first.
- */
- __SetPageLocked(page);
- rc = add_to_page_cache_locked(page, mapping,
- page->index, gfp);
-
- /* give up if we can't stick it in the cache */
- if (rc) {
- __ClearPageLocked(page);
- return rc;
- }
-
- /* move first page to the tmplist */
- *offset = (loff_t)page->index << PAGE_SHIFT;
- *bytes = PAGE_SIZE;
- *nr_pages = 1;
- list_move_tail(&page->lru, tmplist);
-
- /* now try and add more pages onto the request */
- expected_index = page->index + 1;
- list_for_each_entry_safe_reverse(page, tpage, page_list, lru) {
- /* discontinuity ? */
- if (page->index != expected_index)
- break;
-
- /* would this page push the read over the rsize? */
- if (*bytes + PAGE_SIZE > rsize)
- break;
-
- __SetPageLocked(page);
- rc = add_to_page_cache_locked(page, mapping, page->index, gfp);
- if (rc) {
- __ClearPageLocked(page);
- break;
- }
- list_move_tail(&page->lru, tmplist);
- (*bytes) += PAGE_SIZE;
- expected_index++;
- (*nr_pages)++;
- }
- return rc;
-}
-
-static int cifs_readpages(struct file *file, struct address_space *mapping,
- struct list_head *page_list, unsigned num_pages)
+/*
+ * Issue a read operation on behalf of the netfs helper functions. We're asked
+ * to make a read of a certain size at a point in the file. We are permitted
+ * to only read a portion of that, but as long as we read something, the netfs
+ * helper will call us again so that we can issue another read.
+ */
+static void cifs_req_issue_op(struct netfs_read_subrequest *subreq)
{
- int rc;
- int err = 0;
- struct list_head tmplist;
- struct cifsFileInfo *open_file = file->private_data;
- struct cifs_sb_info *cifs_sb = CIFS_FILE_SB(file);
+ struct netfs_read_request *rreq = subreq->rreq;
struct TCP_Server_Info *server;
- pid_t pid;
+ struct cifs_readdata *rdata;
+ struct cifsFileInfo *open_file = rreq->netfs_priv;
+ struct cifs_sb_info *cifs_sb = CIFS_SB(rreq->inode->i_sb);
+ struct cifs_credits credits_on_stack, *credits = &credits_on_stack;
unsigned int xid;
+ pid_t pid;
+ int rc = 0;
+ unsigned int rsize;
xid = get_xid();
- /*
- * Reads as many pages as possible from fscache. Returns -ENOBUFS
- * immediately if the cookie is negative
- *
- * After this point, every page in the list might have PG_fscache set,
- * so we will need to clean that up off of every page we don't use.
- */
- rc = cifs_readpages_from_fscache(mapping->host, mapping, page_list,
- &num_pages);
- if (rc == 0) {
- free_xid(xid);
- return rc;
- }
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
pid = open_file->pid;
else
- pid = current->tgid;
+ pid = current->tgid; // Ummm... This may be a workqueue
- rc = 0;
server = cifs_pick_channel(tlink_tcon(open_file->tlink)->ses);
- cifs_dbg(FYI, "%s: file=%p mapping=%p num_pages=%u\n",
- __func__, file, mapping, num_pages);
+ cifs_dbg(FYI, "%s: op=%08x[%x] mapping=%p len=%zu/%zu\n",
+ __func__, rreq->debug_id, subreq->debug_index, rreq->mapping,
+ subreq->transferred, subreq->len);
- /*
- * Start with the page at end of list and move it to private
- * list. Do the same with any following pages until we hit
- * the rsize limit, hit an index discontinuity, or run out of
- * pages. Issue the async read and then start the loop again
- * until the list is empty.
- *
- * Note that list order is important. The page_list is in
- * the order of declining indexes. When we put the pages in
- * the rdata->pages, then we want them in increasing order.
- */
- while (!list_empty(page_list) && !err) {
- unsigned int i, nr_pages, bytes, rsize;
- loff_t offset;
- struct page *page, *tpage;
- struct cifs_readdata *rdata;
- struct cifs_credits credits_on_stack;
- struct cifs_credits *credits = &credits_on_stack;
-
- if (open_file->invalidHandle) {
+ if (open_file->invalidHandle) {
+ do {
rc = cifs_reopen_file(open_file, true);
- if (rc == -EAGAIN)
- continue;
- else if (rc)
- break;
- }
-
- rc = server->ops->wait_mtu_credits(server, cifs_sb->ctx->rsize,
- &rsize, credits);
+ } while (rc == -EAGAIN);
if (rc)
- break;
-
- /*
- * Give up immediately if rsize is too small to read an entire
- * page. The VFS will fall back to readpage. We should never
- * reach this point however since we set ra_pages to 0 when the
- * rsize is smaller than a cache page.
- */
- if (unlikely(rsize < PAGE_SIZE)) {
- add_credits_and_wake_if(server, credits, 0);
- free_xid(xid);
- return 0;
- }
-
- nr_pages = 0;
- err = readpages_get_pages(mapping, page_list, rsize, &tmplist,
- &nr_pages, &offset, &bytes);
- if (!nr_pages) {
- add_credits_and_wake_if(server, credits, 0);
- break;
- }
-
- rdata = cifs_readdata_alloc(nr_pages, cifs_readv_complete);
- if (!rdata) {
- /* best to give up if we're out of mem */
- list_for_each_entry_safe(page, tpage, &tmplist, lru) {
- list_del(&page->lru);
- lru_cache_add(page);
- unlock_page(page);
- put_page(page);
- }
- rc = -ENOMEM;
- add_credits_and_wake_if(server, credits, 0);
- break;
- }
+ goto out;
+ }
- rdata->cfile = cifsFileInfo_get(open_file);
- rdata->server = server;
- rdata->mapping = mapping;
- rdata->offset = offset;
- rdata->bytes = bytes;
- rdata->pid = pid;
- rdata->pagesz = PAGE_SIZE;
- rdata->tailsz = PAGE_SIZE;
- rdata->read_into_pages = cifs_readpages_read_into_pages;
- rdata->copy_into_pages = cifs_readpages_copy_into_pages;
- rdata->credits = credits_on_stack;
+ rc = server->ops->wait_mtu_credits(server, cifs_sb->ctx->rsize, &rsize, credits);
+ if (rc)
+ goto out;
- list_for_each_entry_safe(page, tpage, &tmplist, lru) {
- list_del(&page->lru);
- rdata->pages[rdata->nr_pages++] = page;
- }
+ rdata = cifs_readdata_alloc(0, NULL);
+ if (!rdata) {
+ add_credits_and_wake_if(server, credits, 0);
+ rc = -ENOMEM;
+ goto out;
+ }
- rc = adjust_credits(server, &rdata->credits, rdata->bytes);
+ rdata->subreq = subreq;
+ rdata->cfile = cifsFileInfo_get(open_file);
+ rdata->server = server;
+ rdata->mapping = rreq->mapping;
+ rdata->offset = subreq->start + subreq->transferred;
+ rdata->bytes = subreq->len - subreq->transferred;
+ rdata->pid = pid;
+ rdata->pagesz = PAGE_SIZE;
+ rdata->tailsz = PAGE_SIZE;
+ rdata->read_into_pages = cifs_readpages_read_into_pages;
+ rdata->copy_into_pages = cifs_readpages_copy_into_pages;
+ rdata->credits = credits_on_stack;
- if (!rc) {
- if (rdata->cfile->invalidHandle)
- rc = -EAGAIN;
- else
- rc = server->ops->async_readv(rdata);
- }
+ iov_iter_xarray(&rdata->iter, READ, &rreq->mapping->i_pages,
+ rdata->offset, rdata->bytes);
- if (rc) {
- add_credits_and_wake_if(server, &rdata->credits, 0);
- for (i = 0; i < rdata->nr_pages; i++) {
- page = rdata->pages[i];
- lru_cache_add(page);
- unlock_page(page);
- put_page(page);
- }
- /* Fallback to the readpage in error/reconnect cases */
- kref_put(&rdata->refcount, cifs_readdata_release);
- break;
- }
+ rc = adjust_credits(server, &rdata->credits, rdata->bytes);
+ if (!rc) {
+ if (rdata->cfile->invalidHandle)
+ rc = -EAGAIN;
+ else
+ rc = server->ops->async_readv(rdata);
+ }
+ if (rc) {
+ add_credits_and_wake_if(server, &rdata->credits, 0);
+ /* Fallback to the readpage in error/reconnect cases */
kref_put(&rdata->refcount, cifs_readdata_release);
}
+ kref_put(&rdata->refcount, cifs_readdata_release);
+
+out:
free_xid(xid);
- return rc;
+ if (rc)
+ netfs_subreq_terminated(subreq, rc, false);
+}
+
+static void cifs_init_rreq(struct netfs_read_request *rreq, struct file *file)
+{
+ rreq->netfs_priv = file->private_data;
}
/*
- * cifs_readpage_worker must be called with the page pinned
+ * Expand the size of a readahead to the size of the rsize, if at least as
+ * large as a page, allowing for the possibility that rsize is not pow-2
+ * aligned.
*/
-static int cifs_readpage_worker(struct file *file, struct page *page,
- loff_t *poffset)
+static void cifs_expand_readahead(struct netfs_read_request *rreq)
{
- char *read_data;
- int rc;
-
- /* Is the page cached? */
- rc = cifs_readpage_from_fscache(file_inode(file), page);
- if (rc == 0)
- goto read_complete;
-
- read_data = kmap(page);
- /* for reads over a certain size could initiate async read ahead */
-
- rc = cifs_read(file, read_data, PAGE_SIZE, poffset);
+ struct cifs_sb_info *cifs_sb = CIFS_SB(rreq->inode->i_sb);
+ unsigned int rsize = cifs_sb->ctx->rsize;
+ loff_t misalignment, i_size = i_size_read(rreq->inode);
- if (rc < 0)
- goto io_error;
- else
- cifs_dbg(FYI, "Bytes read %d\n", rc);
+ if (rsize < PAGE_SIZE)
+ return;
- /* we do not want atime to be less than mtime, it broke some apps */
- file_inode(file)->i_atime = current_time(file_inode(file));
- if (timespec64_compare(&(file_inode(file)->i_atime), &(file_inode(file)->i_mtime)))
- file_inode(file)->i_atime = file_inode(file)->i_mtime;
+ if (rsize < INT_MAX)
+ rsize = roundup_pow_of_two(rsize);
else
- file_inode(file)->i_atime = current_time(file_inode(file));
-
- if (PAGE_SIZE > rc)
- memset(read_data + rc, 0, PAGE_SIZE - rc);
-
- flush_dcache_page(page);
- SetPageUptodate(page);
-
- /* send this page to the cache */
- cifs_readpage_to_fscache(file_inode(file), page);
-
- rc = 0;
+ rsize = ((unsigned int)INT_MAX + 1) / 2;
-io_error:
- kunmap(page);
- unlock_page(page);
+ misalignment = rreq->start & (rsize - 1);
+ if (misalignment) {
+ rreq->start -= misalignment;
+ rreq->len += misalignment;
+ }
-read_complete:
- return rc;
+ rreq->len = round_up(rreq->len, rsize);
+ if (rreq->start < i_size && rreq->len > i_size - rreq->start)
+ rreq->len = i_size - rreq->start;
}
-static int cifs_readpage(struct file *file, struct page *page)
+static void cifs_rreq_done(struct netfs_read_request *rreq)
{
- loff_t offset = page_file_offset(page);
- int rc = -EACCES;
- unsigned int xid;
-
- xid = get_xid();
-
- if (file->private_data == NULL) {
- rc = -EBADF;
- free_xid(xid);
- return rc;
- }
-
- cifs_dbg(FYI, "readpage %p at offset %d 0x%x\n",
- page, (int)offset, (int)offset);
+ struct inode *inode = rreq->inode;
- rc = cifs_readpage_worker(file, page, &offset);
+ /* we do not want atime to be less than mtime, it broke some apps */
+ inode->i_atime = current_time(inode);
+ if (timespec64_compare(&inode->i_atime, &inode->i_mtime))
+ inode->i_atime = inode->i_mtime;
+ else
+ inode->i_atime = current_time(inode);
+}
- free_xid(xid);
- return rc;
+static void cifs_req_cleanup(struct address_space *mapping, void *netfs_priv)
+{
}
+const struct netfs_read_request_ops cifs_req_ops = {
+ .init_rreq = cifs_init_rreq,
+ .expand_readahead = cifs_expand_readahead,
+ .issue_op = cifs_req_issue_op,
+ .done = cifs_rreq_done,
+ .cleanup = cifs_req_cleanup,
+};
+
static int is_inode_writable(struct cifsInodeInfo *cifs_inode)
{
struct cifsFileInfo *open_file;
@@ -4731,34 +4483,21 @@ static int cifs_write_begin(struct file *file, struct address_space *mapping,
loff_t pos, unsigned len, unsigned flags,
struct page **pagep, void **fsdata)
{
- int oncethru = 0;
- pgoff_t index = pos >> PAGE_SHIFT;
- loff_t offset = pos & (PAGE_SIZE - 1);
- loff_t page_start = pos & PAGE_MASK;
- loff_t i_size;
- struct page *page;
- int rc = 0;
+ struct folio *folio;
+ int rc;
cifs_dbg(FYI, "write_begin from %lld len %d\n", (long long)pos, len);
-start:
- page = grab_cache_page_write_begin(mapping, index, flags);
- if (!page) {
- rc = -ENOMEM;
- goto out;
- }
-
- if (PageUptodate(page))
- goto out;
-
- /*
- * If we write a full page it will be up to date, no need to read from
- * the server. If the write is short, we'll end up doing a sync write
- * instead.
+ /* Prefetch area to be written into the cache if we're caching this
+ * file. We need to do this before we get a lock on the page in case
+ * there's more than one writer competing for the same cache block.
*/
- if (len == PAGE_SIZE)
- goto out;
+ rc = netfs_write_begin(file, mapping, pos, len, flags, &folio, fsdata,
+ &cifs_req_ops, NULL);
+ if (rc < 0)
+ return rc;
+#if 0
/*
* optimize away the read when we have an oplock, and we're not
* expecting to use any of the data we'd be reading in. That
@@ -4773,34 +4512,17 @@ static int cifs_write_begin(struct file *file, struct address_space *mapping,
offset + len,
PAGE_SIZE);
/*
- * PageChecked means that the parts of the page
- * to which we're not writing are considered up
- * to date. Once the data is copied to the
- * page, it can be set uptodate.
+ * Marking a folio checked means that the parts of the
+ * page to which we're not writing are considered up to
+ * date. Once the data is copied to the page, it can be
+ * set uptodate.
*/
- SetPageChecked(page);
+ folio_set_checked(folio);
goto out;
}
}
-
- if ((file->f_flags & O_ACCMODE) != O_WRONLY && !oncethru) {
- /*
- * might as well read a page, it is fast enough. If we get
- * an error, we don't need to return it. cifs_write_end will
- * do a sync write instead since PG_uptodate isn't set.
- */
- cifs_readpage_worker(file, page, &page_start);
- put_page(page);
- oncethru = 1;
- goto start;
- } else {
- /* we could try using another file handle if there is one -
- but how would we lock it to prevent close of that handle
- racing with this read? In any case
- this will be written out by write_end so is fine */
- }
-out:
- *pagep = page;
+#endif
+ *pagep = folio_page(folio, pos / PAGE_SIZE);
return rc;
}
@@ -5010,9 +4732,19 @@ static int cifs_set_page_dirty(struct page *page)
#define cifs_set_page_dirty __set_page_dirty_nobuffers
#endif
+static int cifs_readpage(struct file *file, struct page *page)
+{
+ return netfs_readpage(file, page_folio(page), &cifs_req_ops, NULL);
+}
+
+static void cifs_readahead(struct readahead_control *ractl)
+{
+ netfs_readahead(ractl, &cifs_req_ops, NULL);
+}
+
const struct address_space_operations cifs_addr_ops = {
.readpage = cifs_readpage,
- .readpages = cifs_readpages,
+ .readahead = cifs_readahead,
.writepage = cifs_writepage,
.writepages = cifs_writepages,
.write_begin = cifs_write_begin,
diff --git a/fs/cifs/fscache.c b/fs/cifs/fscache.c
index efaac4d5ff55..76e1edc99aec 100644
--- a/fs/cifs/fscache.c
+++ b/fs/cifs/fscache.c
@@ -133,38 +133,3 @@ void cifs_fscache_release_inode_cookie(struct inode *inode)
cifsi->fscache = NULL;
}
}
-
-/*
- * Retrieve a page from FS-Cache
- */
-int __cifs_readpage_from_fscache(struct inode *inode, struct page *page)
-{
- cifs_dbg(FYI, "%s: (fsc:%p, p:%p, i:0x%p\n",
- __func__, CIFS_I(inode)->fscache, page, inode);
- return -ENOBUFS; // Needs conversion to using netfslib
-}
-
-/*
- * Retrieve a set of pages from FS-Cache
- */
-int __cifs_readpages_from_fscache(struct inode *inode,
- struct address_space *mapping,
- struct list_head *pages,
- unsigned *nr_pages)
-{
- cifs_dbg(FYI, "%s: (0x%p/%u/0x%p)\n",
- __func__, CIFS_I(inode)->fscache, *nr_pages, inode);
- return -ENOBUFS; // Needs conversion to using netfslib
-}
-
-void __cifs_readpage_to_fscache(struct inode *inode, struct page *page)
-{
- struct cifsInodeInfo *cifsi = CIFS_I(inode);
-
- WARN_ON(!cifsi->fscache);
-
- cifs_dbg(FYI, "%s: (fsc: %p, p: %p, i: %p)\n",
- __func__, cifsi->fscache, page, inode);
-
- // Needs conversion to using netfslib
-}
diff --git a/fs/cifs/fscache.h b/fs/cifs/fscache.h
index 0fc3f9252c84..9718feac1d68 100644
--- a/fs/cifs/fscache.h
+++ b/fs/cifs/fscache.h
@@ -58,46 +58,11 @@ void cifs_fscache_fill_coherency(struct inode *inode,
}
-extern int cifs_fscache_release_page(struct page *page, gfp_t gfp);
-extern int __cifs_readpage_from_fscache(struct inode *, struct page *);
-extern int __cifs_readpages_from_fscache(struct inode *,
- struct address_space *,
- struct list_head *,
- unsigned *);
-extern void __cifs_readpage_to_fscache(struct inode *, struct page *);
-
static inline struct fscache_cookie *cifs_inode_cookie(struct inode *inode)
{
return CIFS_I(inode)->fscache;
}
-static inline int cifs_readpage_from_fscache(struct inode *inode,
- struct page *page)
-{
- if (CIFS_I(inode)->fscache)
- return __cifs_readpage_from_fscache(inode, page);
-
- return -ENOBUFS;
-}
-
-static inline int cifs_readpages_from_fscache(struct inode *inode,
- struct address_space *mapping,
- struct list_head *pages,
- unsigned *nr_pages)
-{
- if (CIFS_I(inode)->fscache)
- return __cifs_readpages_from_fscache(inode, mapping, pages,
- nr_pages);
- return -ENOBUFS;
-}
-
-static inline void cifs_readpage_to_fscache(struct inode *inode,
- struct page *page)
-{
- if (PageFsCache(page))
- __cifs_readpage_to_fscache(inode, page);
-}
-
#else /* CONFIG_CIFS_FSCACHE */
static inline
void cifs_fscache_fill_coherency(struct inode *inode,
@@ -113,23 +78,6 @@ static inline void cifs_fscache_release_inode_cookie(struct inode *inode) {}
static inline void cifs_fscache_unuse_inode_cookie(struct inode *inode, bool update) {}
static inline struct fscache_cookie *cifs_inode_cookie(struct inode *inode) { return NULL; }
-static inline int
-cifs_readpage_from_fscache(struct inode *inode, struct page *page)
-{
- return -ENOBUFS;
-}
-
-static inline int cifs_readpages_from_fscache(struct inode *inode,
- struct address_space *mapping,
- struct list_head *pages,
- unsigned *nr_pages)
-{
- return -ENOBUFS;
-}
-
-static inline void cifs_readpage_to_fscache(struct inode *inode,
- struct page *page) {}
-
#endif /* CONFIG_CIFS_FSCACHE */
#endif /* _CIFS_FSCACHE_H */
diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index 8b3670388cda..ea2f8a2d9e57 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -23,6 +23,7 @@
#include <linux/uuid.h>
#include <linux/pagemap.h>
#include <linux/xattr.h>
+#include <linux/netfs.h>
#include "cifsglob.h"
#include "cifsacl.h"
#include "cifsproto.h"
@@ -4084,7 +4085,14 @@ smb2_readv_callback(struct mid_q_entry *mid)
tcon->tid, tcon->ses->Suid,
rdata->offset, rdata->got_bytes);
- queue_work(cifsiod_wq, &rdata->work);
+ if (rdata->subreq) {
+ netfs_subreq_terminated(rdata->subreq,
+ (rdata->result == 0 || rdata->result == -EAGAIN) ?
+ rdata->got_bytes : rdata->result, false);
+ kref_put(&rdata->refcount, cifs_readdata_release);
+ } else {
+ queue_work(cifsiod_wq, &rdata->work);
+ }
DeleteMidQEntry(mid);
add_credits(server, &credits, 0);
}
^ permalink raw reply related [flat|nested] 8+ messages in thread* [PATCH v2 2/3] cifs: Reverse the way iov_iters are used in reading
2022-01-06 21:31 [RFC][PATCH v2 0/3] cifs: In-progress conversion to use iov_iters instead of page lists David Howells
2022-01-06 21:32 ` [PATCH v2 1/3] cifs: Use netfslib David Howells
@ 2022-01-06 21:32 ` David Howells
2022-01-07 14:35 ` kernel test robot
2022-01-06 21:32 ` [PATCH v2 3/3] cifs: Eliminate pages list from cifs_readdata, cifs_writedata and smb_rqst David Howells
2 siblings, 1 reply; 8+ messages in thread
From: David Howells @ 2022-01-06 21:32 UTC (permalink / raw)
To: smfrench; +Cc: nspmangalore, dhowells, jlayton, linux-cifs, linux-cachefs
Reverse the way iov_iters are used in reading such that the top layer
passes down an iterator for data to be copied into inside
handle_read_data() and cifs_readv_receive().
Get rid of ->read_into_pages() and ->copy_into_pages() and have the callers
just write directly into the iterator instead.
Generalise setup_aio_ctx_iter() and move it to lib/iov_iter.c as
extract_iter_to_iter(). Other filesystems want to take the iterator passed
to ->read_iter() or ->write_iter() and copy the buffer list too.
Note that extract_iter_to_iter() doesn't actually need to make a separate
allocation for the page array. It can place the page array at the end of
the bvec array storage, provided it traverses both arrays from the 0th
element forwards.
Signed-off-by: David Howells <dhowells@redhat.com>
---
fs/cifs/cifsglob.h | 6 -
fs/cifs/cifsproto.h | 1
fs/cifs/cifssmb.c | 13 ++-
fs/cifs/file.c | 239 ++++-----------------------------------------------
fs/cifs/misc.c | 90 -------------------
fs/cifs/smb2ops.c | 54 ++++--------
include/linux/uio.h | 3 +
lib/iov_iter.c | 94 ++++++++++++++++++++
8 files changed, 146 insertions(+), 354 deletions(-)
diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index a5edae959f60..c1665ef5b946 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -1333,12 +1333,6 @@ struct cifs_readdata {
pid_t pid;
int result;
struct work_struct work;
- int (*read_into_pages)(struct TCP_Server_Info *server,
- struct cifs_readdata *rdata,
- unsigned int len);
- int (*copy_into_pages)(struct TCP_Server_Info *server,
- struct cifs_readdata *rdata,
- struct iov_iter *iter);
struct iov_iter iter;
struct kvec iov[2];
struct TCP_Server_Info *server;
diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h
index 99c239dca807..9cfc160897e9 100644
--- a/fs/cifs/cifsproto.h
+++ b/fs/cifs/cifsproto.h
@@ -587,7 +587,6 @@ enum securityEnum cifs_select_sectype(struct TCP_Server_Info *,
enum securityEnum);
struct cifs_aio_ctx *cifs_aio_ctx_alloc(void);
void cifs_aio_ctx_release(struct kref *refcount);
-int setup_aio_ctx_iter(struct cifs_aio_ctx *ctx, struct iov_iter *iter, int rw);
void smb2_cached_lease_break(struct work_struct *work);
int cifs_alloc_hash(const char *name, struct crypto_shash **shash,
diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
index e068e3bda304..96c901ed1524 100644
--- a/fs/cifs/cifssmb.c
+++ b/fs/cifs/cifssmb.c
@@ -1484,10 +1484,15 @@ cifs_readv_receive(struct TCP_Server_Info *server, struct mid_q_entry *mid)
return cifs_readv_discard(server, mid);
}
- length = rdata->read_into_pages(server, rdata, data_len);
- if (length < 0)
- return length;
-
+#ifdef CONFIG_CIFS_SMB_DIRECT
+ if (rdata->mr)
+ length = data_len; /* An RDMA read is already done. */
+ else
+#endif
+ length = cifs_read_iter_from_socket(server, &rdata->iter,
+ data_len);
+ if (length > 0)
+ rdata->got_bytes += length;
server->total_read += length;
cifs_dbg(FYI, "total_read=%u buflen=%u remaining=%u\n",
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index a3b9c0ecf02c..a12feb3ffdc4 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -3276,11 +3276,13 @@ static ssize_t __cifs_writev(
ctx->iter = *from;
ctx->len = len;
} else {
- rc = setup_aio_ctx_iter(ctx, from, WRITE);
- if (rc) {
+ rc = extract_iter_to_iter(from, &ctx->iter, &ctx->bv);
+ if (rc < 0) {
kref_put(&ctx->refcount, cifs_aio_ctx_release);
return rc;
}
+ ctx->npages = rc;
+ ctx->len = iov_iter_count(&ctx->iter);
}
/* grab a lock here due to read response handlers can access ctx */
@@ -3566,80 +3568,6 @@ cifs_uncached_readv_complete(struct work_struct *work)
kref_put(&rdata->refcount, cifs_uncached_readdata_release);
}
-static int
-uncached_fill_pages(struct TCP_Server_Info *server,
- struct cifs_readdata *rdata, struct iov_iter *iter,
- unsigned int len)
-{
- int result = 0;
- unsigned int i;
- unsigned int nr_pages = rdata->nr_pages;
- unsigned int page_offset = rdata->page_offset;
-
- rdata->got_bytes = 0;
- rdata->tailsz = PAGE_SIZE;
- for (i = 0; i < nr_pages; i++) {
- struct page *page = rdata->pages[i];
- size_t n;
- unsigned int segment_size = rdata->pagesz;
-
- if (i == 0)
- segment_size -= page_offset;
- else
- page_offset = 0;
-
-
- if (len <= 0) {
- /* no need to hold page hostage */
- rdata->pages[i] = NULL;
- rdata->nr_pages--;
- put_page(page);
- continue;
- }
-
- n = len;
- if (len >= segment_size)
- /* enough data to fill the page */
- n = segment_size;
- else
- rdata->tailsz = len;
- len -= n;
-
- if (iter)
- result = copy_page_from_iter(
- page, page_offset, n, iter);
-#ifdef CONFIG_CIFS_SMB_DIRECT
- else if (rdata->mr)
- result = n;
-#endif
- else
- result = cifs_read_page_from_socket(
- server, page, page_offset, n);
- if (result < 0)
- break;
-
- rdata->got_bytes += result;
- }
-
- return rdata->got_bytes > 0 && result != -ECONNABORTED ?
- rdata->got_bytes : result;
-}
-
-static int
-cifs_uncached_read_into_pages(struct TCP_Server_Info *server,
- struct cifs_readdata *rdata, unsigned int len)
-{
- return uncached_fill_pages(server, rdata, NULL, len);
-}
-
-static int
-cifs_uncached_copy_into_pages(struct TCP_Server_Info *server,
- struct cifs_readdata *rdata,
- struct iov_iter *iter)
-{
- 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)
@@ -3725,7 +3653,6 @@ cifs_send_async_read(loff_t offset, size_t len, struct cifsFileInfo *open_file,
int rc;
pid_t pid;
struct TCP_Server_Info *server;
- struct page **pagevec;
size_t start;
struct iov_iter direct_iov = ctx->iter;
@@ -3756,23 +3683,6 @@ cifs_send_async_read(loff_t offset, size_t len, struct cifsFileInfo *open_file,
cur_len = min_t(const size_t, len, rsize);
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 (rc=%zd) iter type %d iov_offset %zd count %zd\n",
- result, iov_iter_type(&direct_iov),
- direct_iov.iov_offset,
- direct_iov.count);
- dump_stack();
-
- rc = result;
- add_credits_and_wake_if(server, credits, 0);
- break;
- }
cur_len = (size_t)result;
iov_iter_advance(&direct_iov, cur_len);
@@ -3815,15 +3725,14 @@ cifs_send_async_read(loff_t offset, size_t len, struct cifsFileInfo *open_file,
rdata->server = server;
rdata->cfile = cifsFileInfo_get(open_file);
- rdata->nr_pages = npages;
+ rdata->nr_pages = ctx->npages;
rdata->offset = offset;
rdata->bytes = cur_len;
rdata->pid = pid;
rdata->pagesz = PAGE_SIZE;
- rdata->read_into_pages = cifs_uncached_read_into_pages;
- rdata->copy_into_pages = cifs_uncached_copy_into_pages;
rdata->credits = credits_on_stack;
rdata->ctx = ctx;
+ rdata->iter = ctx->iter;
kref_get(&ctx->refcount);
rc = adjust_credits(server, &rdata->credits, rdata->bytes);
@@ -4013,11 +3922,13 @@ static ssize_t __cifs_readv(
ctx->iter = *to;
ctx->len = len;
} else {
- rc = setup_aio_ctx_iter(ctx, to, READ);
- if (rc) {
+ rc = extract_iter_to_iter(to, &ctx->iter, &ctx->bv);
+ if (rc < 0) {
kref_put(&ctx->refcount, cifs_aio_ctx_release);
return rc;
}
+ ctx->npages = rc;
+ ctx->len = iov_iter_count(&ctx->iter);
len = ctx->len;
}
@@ -4180,112 +4091,6 @@ int cifs_file_mmap(struct file *file, struct vm_area_struct *vma)
return rc;
}
-static int
-readpages_fill_pages(struct TCP_Server_Info *server,
- struct cifs_readdata *rdata, struct iov_iter *iter,
- unsigned int len)
-{
- int result = 0;
- unsigned int i;
- u64 eof;
- pgoff_t eof_index;
- unsigned int nr_pages = rdata->nr_pages;
- unsigned int page_offset = rdata->page_offset;
-
- /* determine the eof that the server (probably) has */
- eof = CIFS_I(rdata->mapping->host)->server_eof;
- eof_index = eof ? (eof - 1) >> PAGE_SHIFT : 0;
- cifs_dbg(FYI, "eof=%llu eof_index=%lu\n", eof, eof_index);
-
- rdata->got_bytes = 0;
- rdata->tailsz = PAGE_SIZE;
- for (i = 0; i < nr_pages; i++) {
- struct page *page = rdata->pages[i];
- unsigned int to_read = rdata->pagesz;
- size_t n;
-
- if (i == 0)
- to_read -= page_offset;
- else
- page_offset = 0;
-
- n = to_read;
-
- if (len >= to_read) {
- len -= to_read;
- } else if (len > 0) {
- /* enough for partial page, fill and zero the rest */
- zero_user(page, len + page_offset, to_read - len);
- n = rdata->tailsz = len;
- len = 0;
- } else if (page->index > eof_index) {
- /*
- * The VFS will not try to do readahead past the
- * i_size, but it's possible that we have outstanding
- * writes with gaps in the middle and the i_size hasn't
- * caught up yet. Populate those with zeroed out pages
- * to prevent the VFS from repeatedly attempting to
- * fill them until the writes are flushed.
- */
- zero_user(page, 0, PAGE_SIZE);
- lru_cache_add(page);
- flush_dcache_page(page);
- SetPageUptodate(page);
- unlock_page(page);
- put_page(page);
- rdata->pages[i] = NULL;
- rdata->nr_pages--;
- continue;
- } else {
- /* no need to hold page hostage */
- lru_cache_add(page);
- unlock_page(page);
- put_page(page);
- rdata->pages[i] = NULL;
- rdata->nr_pages--;
- continue;
- }
-
- if (iter)
- result = copy_page_from_iter(
- page, page_offset, n, iter);
-#ifdef CONFIG_CIFS_SMB_DIRECT
- else if (rdata->mr)
- result = n;
-#endif
- else
- result = cifs_read_iter_from_socket(server, &rdata->iter, n);
- if (result < 0)
- break;
-
- rdata->got_bytes += result;
- }
-
- return rdata->got_bytes > 0 && result != -ECONNABORTED ?
- rdata->got_bytes : result;
-}
-
-static int
-cifs_readpages_read_into_pages(struct TCP_Server_Info *server,
- struct cifs_readdata *rdata, unsigned int len)
-{
- int rc;
-
- rc = cifs_read_iter_from_socket(server, &rdata->iter, len);
- if (rc > 0)
- rdata->got_bytes += rc;
- return rc;
-}
-
-static int
-cifs_readpages_copy_into_pages(struct TCP_Server_Info *server,
- struct cifs_readdata *rdata,
- struct iov_iter *iter)
-{
- printk("cifs_readpages_copy_into_pages\n");
- return readpages_fill_pages(server, rdata, iter, iter->count);
-}
-
/*
* Issue a read operation on behalf of the netfs helper functions. We're asked
* to make a read of a certain size at a point in the file. We are permitted
@@ -4337,18 +4142,16 @@ static void cifs_req_issue_op(struct netfs_read_subrequest *subreq)
goto out;
}
- rdata->subreq = subreq;
- rdata->cfile = cifsFileInfo_get(open_file);
- rdata->server = server;
- rdata->mapping = rreq->mapping;
- rdata->offset = subreq->start + subreq->transferred;
- rdata->bytes = subreq->len - subreq->transferred;
- rdata->pid = pid;
- rdata->pagesz = PAGE_SIZE;
- rdata->tailsz = PAGE_SIZE;
- rdata->read_into_pages = cifs_readpages_read_into_pages;
- rdata->copy_into_pages = cifs_readpages_copy_into_pages;
- rdata->credits = credits_on_stack;
+ rdata->subreq = subreq;
+ rdata->cfile = cifsFileInfo_get(open_file);
+ rdata->server = server;
+ rdata->mapping = rreq->mapping;
+ rdata->offset = subreq->start + subreq->transferred;
+ rdata->bytes = subreq->len - subreq->transferred;
+ rdata->pid = pid;
+ rdata->pagesz = PAGE_SIZE;
+ rdata->tailsz = PAGE_SIZE;
+ rdata->credits = credits_on_stack;
iov_iter_xarray(&rdata->iter, READ, &rreq->mapping->i_pages,
rdata->offset, rdata->bytes);
@@ -4652,7 +4455,7 @@ void cifs_oplock_break(struct work_struct *work)
* In the non-cached mode (mount with cache=none), we shunt off direct read and write requests
* so this method should never be called.
*
- * Direct IO is not yet supported in the cached mode.
+ * Direct IO is not yet supported in the cached mode.
*/
static ssize_t
cifs_direct_io(struct kiocb *iocb, struct iov_iter *iter)
diff --git a/fs/cifs/misc.c b/fs/cifs/misc.c
index 5148d48d6a35..ece7fc8a7740 100644
--- a/fs/cifs/misc.c
+++ b/fs/cifs/misc.c
@@ -974,96 +974,6 @@ cifs_aio_ctx_release(struct kref *refcount)
kfree(ctx);
}
-#define CIFS_AIO_KMALLOC_LIMIT (1024 * 1024)
-
-int
-setup_aio_ctx_iter(struct cifs_aio_ctx *ctx, struct iov_iter *iter, int rw)
-{
- ssize_t rc;
- unsigned int cur_npages;
- unsigned int npages = 0;
- unsigned int i;
- size_t len;
- size_t count = iov_iter_count(iter);
- unsigned int saved_len;
- size_t start;
- unsigned int max_pages = iov_iter_npages(iter, INT_MAX);
- struct page **pages = NULL;
- struct bio_vec *bv = NULL;
-
- if (iov_iter_is_kvec(iter)) {
- memcpy(&ctx->iter, iter, sizeof(*iter));
- ctx->len = count;
- iov_iter_advance(iter, count);
- return 0;
- }
-
- if (array_size(max_pages, sizeof(*bv)) <= CIFS_AIO_KMALLOC_LIMIT)
- bv = kmalloc_array(max_pages, sizeof(*bv), GFP_KERNEL);
-
- if (!bv) {
- bv = vmalloc(array_size(max_pages, sizeof(*bv)));
- if (!bv)
- return -ENOMEM;
- }
-
- if (array_size(max_pages, sizeof(*pages)) <= CIFS_AIO_KMALLOC_LIMIT)
- pages = kmalloc_array(max_pages, sizeof(*pages), GFP_KERNEL);
-
- if (!pages) {
- pages = vmalloc(array_size(max_pages, sizeof(*pages)));
- if (!pages) {
- kvfree(bv);
- return -ENOMEM;
- }
- }
-
- saved_len = count;
-
- while (count && npages < max_pages) {
- rc = iov_iter_get_pages(iter, pages, count, max_pages, &start);
- if (rc < 0) {
- cifs_dbg(VFS, "Couldn't get user pages (rc=%zd)\n", rc);
- break;
- }
-
- if (rc > count) {
- cifs_dbg(VFS, "get pages rc=%zd more than %zu\n", rc,
- count);
- break;
- }
-
- iov_iter_advance(iter, rc);
- count -= rc;
- rc += start;
- cur_npages = DIV_ROUND_UP(rc, PAGE_SIZE);
-
- if (npages + cur_npages > max_pages) {
- cifs_dbg(VFS, "out of vec array capacity (%u vs %u)\n",
- npages + cur_npages, max_pages);
- break;
- }
-
- for (i = 0; i < cur_npages; i++) {
- len = rc > PAGE_SIZE ? PAGE_SIZE : rc;
- bv[npages + i].bv_page = pages[i];
- bv[npages + i].bv_offset = start;
- bv[npages + i].bv_len = len - start;
- rc -= len;
- start = 0;
- }
-
- npages += cur_npages;
- }
-
- kvfree(pages);
- ctx->bv = bv;
- ctx->len = saved_len - count;
- ctx->npages = npages;
- iov_iter_bvec(&ctx->iter, rw, ctx->bv, npages, ctx->len);
- return 0;
-}
-
/**
* cifs_alloc_hash - allocate hash and hash context together
* @name: The name of the crypto hash algo
diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index c5b1dea54ebc..a5ce04331613 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -4754,30 +4754,24 @@ read_data_into_pages(struct TCP_Server_Info *server, struct page **pages,
}
static int
-init_read_bvec(struct page **pages, unsigned int npages, unsigned int data_size,
- unsigned int cur_off, struct bio_vec **page_vec)
+cifs_copy_pages_to_iter(struct page **pages, unsigned int npages, unsigned int data_size,
+ unsigned int cur_off, struct iov_iter *iter)
{
- struct bio_vec *bvec;
- int i;
-
- bvec = kcalloc(npages, sizeof(struct bio_vec), GFP_KERNEL);
- if (!bvec)
- return -ENOMEM;
+ unsigned int i;
for (i = 0; i < npages; i++) {
- bvec[i].bv_page = pages[i];
- bvec[i].bv_offset = (i == 0) ? cur_off : 0;
- bvec[i].bv_len = min_t(unsigned int, PAGE_SIZE, data_size);
- data_size -= bvec[i].bv_len;
- }
-
- if (data_size != 0) {
- cifs_dbg(VFS, "%s: something went wrong\n", __func__);
- kfree(bvec);
- return -EIO;
+ size_t n, len = min_t(unsigned int, PAGE_SIZE, data_size);
+
+ n = copy_page_to_iter(pages[i],
+ (i == 0) ? cur_off : 0,
+ len, iter);
+ if (n != len) {
+ cifs_dbg(VFS, "%s: something went wrong\n", __func__);
+ return -EIO;
+ }
+ data_size -= n;
}
- *page_vec = bvec;
return 0;
}
@@ -4794,9 +4788,6 @@ handle_read_data(struct TCP_Server_Info *server, struct mid_q_entry *mid,
unsigned int pad_len;
struct cifs_readdata *rdata = mid->callback_data;
struct smb2_hdr *shdr = (struct smb2_hdr *)buf;
- struct bio_vec *bvec = NULL;
- struct iov_iter iter;
- struct kvec iov;
int length;
bool use_rdma_mr = false;
@@ -4895,8 +4886,9 @@ handle_read_data(struct TCP_Server_Info *server, struct mid_q_entry *mid,
return 0;
}
- rdata->result = init_read_bvec(pages, npages, page_data_size,
- cur_off, &bvec);
+ /* Copy the data to the output I/O iterator. */
+ rdata->result = cifs_copy_pages_to_iter(pages, npages, page_data_size,
+ cur_off, &rdata->iter);
if (rdata->result != 0) {
if (is_offloaded)
mid->mid_state = MID_RESPONSE_MALFORMED;
@@ -4905,13 +4897,12 @@ handle_read_data(struct TCP_Server_Info *server, struct mid_q_entry *mid,
return 0;
}
- iov_iter_bvec(&iter, WRITE, bvec, npages, data_len);
} else if (buf_len >= data_offset + data_len) {
/* read response payload is in buf */
WARN_ONCE(npages > 0, "read data can be either in buf or in pages");
- iov.iov_base = buf + data_offset;
- iov.iov_len = data_len;
- iov_iter_kvec(&iter, WRITE, &iov, 1, data_len);
+ length = copy_to_iter(buf + data_offset, data_len, &rdata->iter);
+ if (length < 0)
+ return length;
} else {
/* read response payload cannot be in both buf and pages */
WARN_ONCE(1, "buf can not contain only a part of read data");
@@ -4923,13 +4914,6 @@ handle_read_data(struct TCP_Server_Info *server, struct mid_q_entry *mid,
return 0;
}
- length = rdata->copy_into_pages(server, rdata, &iter);
-
- kfree(bvec);
-
- if (length < 0)
- return length;
-
if (is_offloaded)
mid->mid_state = MID_RESPONSE_RECEIVED;
else
diff --git a/include/linux/uio.h b/include/linux/uio.h
index 6350354f97e9..931528bc2eab 100644
--- a/include/linux/uio.h
+++ b/include/linux/uio.h
@@ -247,6 +247,9 @@ ssize_t iov_iter_get_pages(struct iov_iter *i, struct page **pages,
size_t maxsize, unsigned maxpages, size_t *start);
ssize_t iov_iter_get_pages_alloc(struct iov_iter *i, struct page ***pages,
size_t maxsize, size_t *start);
+ssize_t extract_iter_to_iter(struct iov_iter *orig,
+ struct iov_iter *new,
+ struct bio_vec **_bv);
int iov_iter_npages(const struct iov_iter *i, int maxpages);
void iov_iter_restore(struct iov_iter *i, struct iov_iter_state *state);
diff --git a/lib/iov_iter.c b/lib/iov_iter.c
index 66a740e6e153..cebfdb617fd8 100644
--- a/lib/iov_iter.c
+++ b/lib/iov_iter.c
@@ -1696,6 +1696,100 @@ ssize_t iov_iter_get_pages_alloc(struct iov_iter *i,
}
EXPORT_SYMBOL(iov_iter_get_pages_alloc);
+/**
+ * extract_iter_to_iter - Extract the pages from one iterator into another
+ * @orig: The original iterator
+ * @new: The iterator to be set up
+ * @_bv: Where to store the allocated bvec table pointer, if allocated
+ *
+ * Extract the page fragments from an iterator and build up a second iterator
+ * that refers to all of those bits so that the original iterator can be
+ * disposed of.
+ *
+ * If a bvec array is created, the number of pages in the array is returned and
+ * a pointer to the array is saved into *@_bv;
+ */
+ssize_t extract_iter_to_iter(struct iov_iter *orig,
+ struct iov_iter *new,
+ struct bio_vec **_bv)
+{
+ struct bio_vec *bv = NULL;
+ struct page **pages;
+ unsigned int cur_npages;
+ unsigned int max_pages = iov_iter_npages(orig, INT_MAX);
+ unsigned int saved_len;
+ unsigned int npages = 0;
+ unsigned int i;
+ ssize_t ret;
+ size_t bv_size, pg_size;
+ size_t count = iov_iter_count(orig);
+ size_t start;
+ size_t len;
+
+ *_bv = NULL;
+
+ if (iov_iter_is_kvec(orig) || iov_iter_is_discard(orig)) {
+ memcpy(new, orig, sizeof(*new));
+ iov_iter_advance(orig, count);
+ return 0;
+ }
+
+ bv_size = array_size(max_pages, sizeof(*bv));
+ bv = kvmalloc(bv_size, GFP_KERNEL);
+ if (!bv)
+ return -ENOMEM;
+
+ /* Put the page list at the end of the bvec list storage. bvec
+ * elements are larger than page pointers, so as long as we work
+ * 0->last, we should be fine.
+ */
+ pg_size = array_size(max_pages, sizeof(*pages));
+ pages = (void *)bv + bv_size - pg_size;
+
+ saved_len = count;
+
+ while (count && npages < max_pages) {
+ ret = iov_iter_get_pages(orig, pages, count, max_pages - npages,
+ &start);
+ if (ret < 0) {
+ pr_err("Couldn't get user pages (rc=%zd)\n", ret);
+ break;
+ }
+
+ if (ret > count) {
+ pr_err("get_pages rc=%zd more than %zu\n", ret, count);
+ break;
+ }
+
+ iov_iter_advance(orig, ret);
+ count -= ret;
+ ret += start;
+ cur_npages = DIV_ROUND_UP(ret, PAGE_SIZE);
+
+ if (npages + cur_npages > max_pages) {
+ pr_err("Out of bvec array capacity (%u vs %u)\n",
+ npages + cur_npages, max_pages);
+ break;
+ }
+
+ for (i = 0; i < cur_npages; i++) {
+ len = ret > PAGE_SIZE ? PAGE_SIZE : ret;
+ bv[npages + i].bv_page = *pages++;
+ bv[npages + i].bv_offset = start;
+ bv[npages + i].bv_len = len - start;
+ ret -= len;
+ start = 0;
+ }
+
+ npages += cur_npages;
+ }
+
+ *_bv = bv;
+ iov_iter_bvec(new, iov_iter_rw(orig), bv, npages, saved_len - count);
+ return npages;
+}
+EXPORT_SYMBOL(extract_iter_to_iter);
+
size_t csum_and_copy_from_iter(void *addr, size_t bytes, __wsum *csum,
struct iov_iter *i)
{
^ permalink raw reply related [flat|nested] 8+ messages in thread* [PATCH v2 3/3] cifs: Eliminate pages list from cifs_readdata, cifs_writedata and smb_rqst
2022-01-06 21:31 [RFC][PATCH v2 0/3] cifs: In-progress conversion to use iov_iters instead of page lists David Howells
2022-01-06 21:32 ` [PATCH v2 1/3] cifs: Use netfslib David Howells
2022-01-06 21:32 ` [PATCH v2 2/3] cifs: Reverse the way iov_iters are used in reading David Howells
@ 2022-01-06 21:32 ` David Howells
2022-01-07 17:32 ` kernel test robot
2 siblings, 1 reply; 8+ messages in thread
From: David Howells @ 2022-01-06 21:32 UTC (permalink / raw)
To: smfrench; +Cc: nspmangalore, dhowells, jlayton, linux-cifs, linux-cachefs
Replace the list of pages in the cifs_readdata, cifs_writedata and smb_rqst
structs with iterators.
---
fs/cifs/cifsencrypt.c | 40 +-
fs/cifs/cifsfs.h | 3
fs/cifs/cifsglob.h | 22 -
fs/cifs/cifsproto.h | 7
fs/cifs/cifssmb.c | 206 ++++++++----
fs/cifs/file.c | 808 +++++++++++++++++++------------------------------
fs/cifs/misc.c | 19 -
fs/cifs/smb2ops.c | 134 ++++----
fs/cifs/smb2pdu.c | 12 -
fs/cifs/transport.c | 41 --
include/linux/uio.h | 4
lib/iov_iter.c | 42 +++
12 files changed, 603 insertions(+), 735 deletions(-)
diff --git a/fs/cifs/cifsencrypt.c b/fs/cifs/cifsencrypt.c
index d118282071b3..1b83c72462d2 100644
--- a/fs/cifs/cifsencrypt.c
+++ b/fs/cifs/cifsencrypt.c
@@ -24,12 +24,27 @@
#include "../smbfs_common/arc4.h"
#include <crypto/aead.h>
+static ssize_t cifs_signature_scan(struct iov_iter *i, const void *p,
+ size_t len, size_t off, void *priv)
+{
+ struct shash_desc *shash = priv;
+ int rc;
+
+ rc = crypto_shash_update(shash, p, len);
+ if (rc) {
+ cifs_dbg(VFS, "%s: Could not update with payload\n", __func__);
+ return rc;
+ }
+
+ return len;
+}
+
int __cifs_calc_signature(struct smb_rqst *rqst,
struct TCP_Server_Info *server, char *signature,
struct shash_desc *shash)
{
int i;
- int rc;
+ ssize_t rc;
struct kvec *iov = rqst->rq_iov;
int n_vec = rqst->rq_nvec;
int is_smb2 = server->vals->header_preamble_size == 0;
@@ -62,25 +77,10 @@ int __cifs_calc_signature(struct smb_rqst *rqst,
}
}
- /* now hash over the rq_pages array */
- for (i = 0; i < rqst->rq_npages; i++) {
- void *kaddr;
- unsigned int len, offset;
-
- rqst_page_get_length(rqst, i, &len, &offset);
-
- kaddr = (char *) kmap(rqst->rq_pages[i]) + offset;
-
- rc = crypto_shash_update(shash, kaddr, len);
- if (rc) {
- cifs_dbg(VFS, "%s: Could not update with payload\n",
- __func__);
- kunmap(rqst->rq_pages[i]);
- return rc;
- }
-
- kunmap(rqst->rq_pages[i]);
- }
+ rc = iov_iter_scan(&rqst->rq_iter, iov_iter_count(&rqst->rq_iter),
+ cifs_signature_scan, shash);
+ if (rc < 0)
+ return rc;
rc = crypto_shash_final(shash, signature);
if (rc)
diff --git a/fs/cifs/cifsfs.h b/fs/cifs/cifsfs.h
index 9e5d9e192ef0..c4b679dd6d5e 100644
--- a/fs/cifs/cifsfs.h
+++ b/fs/cifs/cifsfs.h
@@ -110,6 +110,9 @@ extern int cifs_file_strict_mmap(struct file * , struct vm_area_struct *);
extern const struct file_operations cifs_dir_ops;
extern int cifs_dir_open(struct inode *inode, struct file *file);
extern int cifs_readdir(struct file *file, struct dir_context *ctx);
+extern void cifs_pages_written_back(struct inode *inode, loff_t start, unsigned int len);
+extern void cifs_pages_write_failed(struct inode *inode, loff_t start, unsigned int len);
+extern void cifs_pages_write_redirty(struct inode *inode, loff_t start, unsigned int len);
/* Functions related to dir entries */
extern const struct dentry_operations cifs_dentry_ops;
diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index c1665ef5b946..c33803141712 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -185,11 +185,8 @@ struct cifs_cred {
struct smb_rqst {
struct kvec *rq_iov; /* array of kvecs */
unsigned int rq_nvec; /* number of kvecs in array */
- struct page **rq_pages; /* pointer to array of page ptrs */
- unsigned int rq_offset; /* the offset to the 1st page */
- unsigned int rq_npages; /* number pages in array */
- unsigned int rq_pagesz; /* page size to use */
- unsigned int rq_tailsz; /* length of last page */
+ struct iov_iter rq_iter; /* Data iterator */
+ struct xarray rq_buffer; /* Page buffer for encryption */
};
struct mid_q_entry;
@@ -1330,21 +1327,18 @@ struct cifs_readdata {
__u64 offset;
unsigned int bytes;
unsigned int got_bytes;
+ unsigned int bv_count;
pid_t pid;
int result;
struct work_struct work;
struct iov_iter iter;
+ struct bio_vec *bv;
struct kvec iov[2];
struct TCP_Server_Info *server;
#ifdef CONFIG_CIFS_SMB_DIRECT
struct smbd_mr *mr;
#endif
- unsigned int pagesz;
- unsigned int page_offset;
- unsigned int tailsz;
struct cifs_credits credits;
- unsigned int nr_pages;
- struct page **pages;
};
/* asynchronous write support */
@@ -1356,20 +1350,18 @@ struct cifs_writedata {
struct work_struct work;
struct cifsFileInfo *cfile;
struct cifs_aio_ctx *ctx;
+ struct iov_iter iter;
+ struct bio_vec *bv;
__u64 offset;
pid_t pid;
unsigned int bytes;
+ unsigned int bv_count;
int result;
struct TCP_Server_Info *server;
#ifdef CONFIG_CIFS_SMB_DIRECT
struct smbd_mr *mr;
#endif
- unsigned int pagesz;
- unsigned int page_offset;
- unsigned int tailsz;
struct cifs_credits credits;
- unsigned int nr_pages;
- struct page **pages;
};
/*
diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h
index 9cfc160897e9..799c28f90bf1 100644
--- a/fs/cifs/cifsproto.h
+++ b/fs/cifs/cifsproto.h
@@ -567,10 +567,7 @@ int cifs_readv_receive(struct TCP_Server_Info *server, struct mid_q_entry *mid);
int cifs_async_writev(struct cifs_writedata *wdata,
void (*release)(struct kref *kref));
void cifs_writev_complete(struct work_struct *work);
-struct cifs_writedata *cifs_writedata_alloc(unsigned int nr_pages,
- work_func_t complete);
-struct cifs_writedata *cifs_writedata_direct_alloc(struct page **pages,
- work_func_t complete);
+struct cifs_writedata *cifs_writedata_alloc(work_func_t complete);
void cifs_writedata_release(struct kref *refcount);
int cifs_query_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
struct cifs_sb_info *cifs_sb,
@@ -593,8 +590,6 @@ int cifs_alloc_hash(const char *name, struct crypto_shash **shash,
struct sdesc **sdesc);
void cifs_free_hash(struct crypto_shash **shash, struct sdesc **sdesc);
-extern void rqst_page_get_length(struct smb_rqst *rqst, unsigned int page,
- unsigned int *len, unsigned int *offset);
struct cifs_chan *
cifs_ses_find_chan(struct cifs_ses *ses, struct TCP_Server_Info *server);
int cifs_try_adding_channels(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses);
diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
index 96c901ed1524..11a6cf44a88f 100644
--- a/fs/cifs/cifssmb.c
+++ b/fs/cifs/cifssmb.c
@@ -25,6 +25,7 @@
#include <linux/uaccess.h>
#include <linux/netfs.h>
#include "cifspdu.h"
+#include "cifsfs.h"
#include "cifsglob.h"
#include "cifsacl.h"
#include "cifsproto.h"
@@ -1516,11 +1517,7 @@ cifs_readv_callback(struct mid_q_entry *mid)
struct TCP_Server_Info *server = tcon->ses->server;
struct smb_rqst rqst = { .rq_iov = rdata->iov,
.rq_nvec = 2,
- .rq_pages = rdata->pages,
- .rq_offset = rdata->page_offset,
- .rq_npages = rdata->nr_pages,
- .rq_pagesz = rdata->pagesz,
- .rq_tailsz = rdata->tailsz };
+ .rq_iter = rdata->iter };
struct cifs_credits credits = { .value = 1, .instance = 0 };
cifs_dbg(FYI, "%s: mid=%llu state=%d result=%d bytes=%u\n",
@@ -1883,10 +1880,93 @@ cifs_writedata_release(struct kref *refcount)
if (wdata->cfile)
cifsFileInfo_put(wdata->cfile);
- kvfree(wdata->pages);
kfree(wdata);
}
+/*
+ * Completion of write to server.
+ */
+void cifs_pages_written_back(struct inode *inode, loff_t start, unsigned int len)
+{
+ struct address_space *mapping = inode->i_mapping;
+ struct folio *folio;
+ pgoff_t end;
+
+ XA_STATE(xas, &mapping->i_pages, start / PAGE_SIZE);
+
+ rcu_read_lock();
+
+ end = (start + len - 1) / PAGE_SIZE;
+ xas_for_each(&xas, folio, end) {
+ if (!folio_test_writeback(folio)) {
+ pr_err("bad %x @%llx page %lx %lx\n",
+ len, start, folio_index(folio), end);
+ BUG();
+ }
+
+ folio_detach_private(folio);
+ folio_end_writeback(folio);
+ }
+
+ rcu_read_unlock();
+}
+
+/*
+ * Failure of write to server.
+ */
+void cifs_pages_write_failed(struct inode *inode, loff_t start, unsigned int len)
+{
+ struct address_space *mapping = inode->i_mapping;
+ struct folio *folio;
+ pgoff_t end;
+
+ XA_STATE(xas, &mapping->i_pages, start / PAGE_SIZE);
+
+ rcu_read_lock();
+
+ end = (start + len - 1) / PAGE_SIZE;
+ xas_for_each(&xas, folio, end) {
+ if (!folio_test_writeback(folio)) {
+ pr_err("bad %x @%llx page %lx %lx\n",
+ len, start, folio_index(folio), end);
+ BUG();
+ }
+
+ folio_set_error(folio);
+ folio_end_writeback(folio);
+ }
+
+ rcu_read_unlock();
+}
+
+/*
+ * Redirty pages after a temporary failure.
+ */
+void cifs_pages_write_redirty(struct inode *inode, loff_t start, unsigned int len)
+{
+ struct address_space *mapping = inode->i_mapping;
+ struct folio *folio;
+ pgoff_t end;
+
+ XA_STATE(xas, &mapping->i_pages, start / PAGE_SIZE);
+
+ rcu_read_lock();
+
+ end = (start + len - 1) / PAGE_SIZE;
+ xas_for_each(&xas, folio, end) {
+ if (!folio_test_writeback(folio)) {
+ pr_err("bad %x @%llx page %lx %lx\n",
+ len, start, folio_index(folio), end);
+ BUG();
+ }
+
+ filemap_dirty_folio(folio->mapping, folio);
+ folio_end_writeback(folio);
+ }
+
+ rcu_read_unlock();
+}
+
/*
* Write failed with a retryable error. Resend the write request. It's also
* possible that the page was redirtied so re-clean the page.
@@ -1894,51 +1974,56 @@ cifs_writedata_release(struct kref *refcount)
static void
cifs_writev_requeue(struct cifs_writedata *wdata)
{
- int i, rc = 0;
+ int rc = 0;
struct inode *inode = d_inode(wdata->cfile->dentry);
struct TCP_Server_Info *server;
- unsigned int rest_len;
+ unsigned int rest_len = wdata->bytes;
+ loff_t fpos = wdata->offset;
server = tlink_tcon(wdata->cfile->tlink)->ses->server;
- i = 0;
- rest_len = wdata->bytes;
do {
struct cifs_writedata *wdata2;
- unsigned int j, nr_pages, wsize, tailsz, cur_len;
+ unsigned int wsize, cur_len;
wsize = server->ops->wp_retry_size(inode);
if (wsize < rest_len) {
- nr_pages = wsize / PAGE_SIZE;
- if (!nr_pages) {
+ if (wsize < PAGE_SIZE) {
rc = -ENOTSUPP;
break;
}
- cur_len = nr_pages * PAGE_SIZE;
- tailsz = PAGE_SIZE;
+ cur_len = min(round_down(wsize, PAGE_SIZE), rest_len);
} else {
- nr_pages = DIV_ROUND_UP(rest_len, PAGE_SIZE);
cur_len = rest_len;
- tailsz = rest_len - (nr_pages - 1) * PAGE_SIZE;
}
- wdata2 = cifs_writedata_alloc(nr_pages, cifs_writev_complete);
+ wdata2 = cifs_writedata_alloc(cifs_writev_complete);
if (!wdata2) {
rc = -ENOMEM;
break;
}
- for (j = 0; j < nr_pages; j++) {
- wdata2->pages[j] = wdata->pages[i + j];
- lock_page(wdata2->pages[j]);
- clear_page_dirty_for_io(wdata2->pages[j]);
- }
-
wdata2->sync_mode = wdata->sync_mode;
- wdata2->nr_pages = nr_pages;
- wdata2->offset = page_offset(wdata2->pages[0]);
- wdata2->pagesz = PAGE_SIZE;
- wdata2->tailsz = tailsz;
- wdata2->bytes = cur_len;
+ wdata2->offset = fpos;
+ wdata2->bytes = cur_len;
+ wdata2->iter = wdata->iter;
+
+ iov_iter_advance(&wdata2->iter, fpos - wdata->offset);
+ iov_iter_truncate(&wdata2->iter, wdata2->bytes);
+
+#if 0
+ if (iov_iter_is_xarray(&wdata2->iter)) {
+ /* TODO: Check for pages having been redirtied and
+ * clean them. We can do this by walking the xarray.
+ * If it's not an xarray, then it's a DIO and we
+ * shouldn't be mucking around with the page bits.
+ */
+ for (j = 0; j < nr_pages; j++) {
+ wdata2->pages[j] = wdata->pages[i + j];
+ lock_page(wdata2->pages[j]);
+ clear_page_dirty_for_io(wdata2->pages[j]);
+ }
+ }
+#endif
rc = cifs_get_writable_file(CIFS_I(inode), FIND_WR_ANY,
&wdata2->cfile);
@@ -1953,33 +2038,25 @@ cifs_writev_requeue(struct cifs_writedata *wdata)
cifs_writedata_release);
}
- for (j = 0; j < nr_pages; j++) {
- unlock_page(wdata2->pages[j]);
- if (rc != 0 && !is_retryable_error(rc)) {
- SetPageError(wdata2->pages[j]);
- end_page_writeback(wdata2->pages[j]);
- put_page(wdata2->pages[j]);
- }
- }
+ if (iov_iter_is_xarray(&wdata2->iter))
+ cifs_pages_written_back(inode, wdata2->offset, wdata2->bytes);
kref_put(&wdata2->refcount, cifs_writedata_release);
if (rc) {
if (is_retryable_error(rc))
continue;
- i += nr_pages;
+ fpos += cur_len;
+ rest_len -= cur_len;
break;
}
+ fpos += cur_len;
rest_len -= cur_len;
- i += nr_pages;
- } while (i < wdata->nr_pages);
+ } while (rest_len > 0);
- /* cleanup remaining pages from the original wdata */
- for (; i < wdata->nr_pages; i++) {
- SetPageError(wdata->pages[i]);
- end_page_writeback(wdata->pages[i]);
- put_page(wdata->pages[i]);
- }
+ /* Clean up remaining pages from the original wdata */
+ if (iov_iter_is_xarray(&wdata->iter))
+ cifs_pages_written_back(inode, fpos, rest_len);
if (rc != 0 && !is_retryable_error(rc))
mapping_set_error(inode->i_mapping, rc);
@@ -1992,7 +2069,6 @@ cifs_writev_complete(struct work_struct *work)
struct cifs_writedata *wdata = container_of(work,
struct cifs_writedata, work);
struct inode *inode = d_inode(wdata->cfile->dentry);
- int i = 0;
if (wdata->result == 0) {
spin_lock(&inode->i_lock);
@@ -2003,39 +2079,25 @@ cifs_writev_complete(struct work_struct *work)
} else if (wdata->sync_mode == WB_SYNC_ALL && wdata->result == -EAGAIN)
return cifs_writev_requeue(wdata);
- for (i = 0; i < wdata->nr_pages; i++) {
- struct page *page = wdata->pages[i];
- if (wdata->result == -EAGAIN)
- __set_page_dirty_nobuffers(page);
- else if (wdata->result < 0)
- SetPageError(page);
- end_page_writeback(page);
- put_page(page);
- }
+ if (wdata->result == -EAGAIN)
+ cifs_pages_write_redirty(inode, wdata->offset, wdata->bytes);
+ else if (wdata->result < 0)
+ cifs_pages_write_failed(inode, wdata->offset, wdata->bytes);
+ else
+ cifs_pages_written_back(inode, wdata->offset, wdata->bytes);
+
if (wdata->result != -EAGAIN)
mapping_set_error(inode->i_mapping, wdata->result);
kref_put(&wdata->refcount, cifs_writedata_release);
}
struct cifs_writedata *
-cifs_writedata_alloc(unsigned int nr_pages, work_func_t complete)
-{
- struct page **pages =
- kcalloc(nr_pages, sizeof(struct page *), GFP_NOFS);
- if (pages)
- return cifs_writedata_direct_alloc(pages, complete);
-
- return NULL;
-}
-
-struct cifs_writedata *
-cifs_writedata_direct_alloc(struct page **pages, work_func_t complete)
+cifs_writedata_alloc(work_func_t complete)
{
struct cifs_writedata *wdata;
wdata = kzalloc(sizeof(*wdata), GFP_NOFS);
if (wdata != NULL) {
- wdata->pages = pages;
kref_init(&wdata->refcount);
INIT_LIST_HEAD(&wdata->list);
init_completion(&wdata->done);
@@ -2143,11 +2205,7 @@ cifs_async_writev(struct cifs_writedata *wdata,
rqst.rq_iov = iov;
rqst.rq_nvec = 2;
- rqst.rq_pages = wdata->pages;
- rqst.rq_offset = wdata->page_offset;
- rqst.rq_npages = wdata->nr_pages;
- rqst.rq_pagesz = wdata->pagesz;
- rqst.rq_tailsz = wdata->tailsz;
+ rqst.rq_iter = wdata->iter;
cifs_dbg(FYI, "async write at %llu %u bytes\n",
wdata->offset, wdata->bytes);
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index a12feb3ffdc4..e53df5398dc4 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -2269,294 +2269,333 @@ static int cifs_partialpagewrite(struct page *page, unsigned from, unsigned to)
return rc;
}
-static struct cifs_writedata *
-wdata_alloc_and_fillpages(pgoff_t tofind, struct address_space *mapping,
- pgoff_t end, pgoff_t *index,
- unsigned int *found_pages)
+/*
+ * Extend the region to be written back to include subsequent contiguously
+ * dirty pages if possible, but don't sleep while doing so.
+ */
+static void cifs_extend_writeback(struct address_space *mapping,
+ long *_count,
+ loff_t start,
+ loff_t max_len,
+ unsigned int *_len)
{
- struct cifs_writedata *wdata;
-
- wdata = cifs_writedata_alloc((unsigned int)tofind,
- cifs_writev_complete);
- if (!wdata)
- return NULL;
-
- *found_pages = find_get_pages_range_tag(mapping, index, end,
- PAGECACHE_TAG_DIRTY, tofind, wdata->pages);
- return wdata;
-}
+ struct pagevec pvec;
+ struct folio *folio;
+ unsigned int psize;
+ loff_t len = *_len;
+ pgoff_t index = (start + len) / PAGE_SIZE;
+ bool stop = true;
+ unsigned int i;
-static unsigned int
-wdata_prepare_pages(struct cifs_writedata *wdata, unsigned int found_pages,
- struct address_space *mapping,
- struct writeback_control *wbc,
- pgoff_t end, pgoff_t *index, pgoff_t *next, bool *done)
-{
- unsigned int nr_pages = 0, i;
- struct page *page;
+ XA_STATE(xas, &mapping->i_pages, index);
+ pagevec_init(&pvec);
- for (i = 0; i < found_pages; i++) {
- page = wdata->pages[i];
- /*
- * At this point we hold neither the i_pages lock nor the
- * page lock: the page may be truncated or invalidated
- * (changing page->mapping to NULL), or even swizzled
- * back from swapper_space to tmpfs file mapping
+ do {
+ /* Firstly, we gather up a batch of contiguous dirty pages
+ * under the RCU read lock - but we can't clear the dirty flags
+ * there if any of those pages are mapped.
*/
+ rcu_read_lock();
- if (nr_pages == 0)
- lock_page(page);
- else if (!trylock_page(page))
- break;
+ xas_for_each(&xas, folio, ULONG_MAX) {
+ stop = true;
+ if (xas_retry(&xas, folio))
+ continue;
+ if (xa_is_value(folio))
+ break;
+ if (folio_index(folio) != index)
+ break;
- if (unlikely(page->mapping != mapping)) {
- unlock_page(page);
- break;
- }
+ if (!folio_try_get_rcu(folio)) {
+ xas_reset(&xas);
+ continue;
+ }
- if (!wbc->range_cyclic && page->index > end) {
- *done = true;
- unlock_page(page);
- break;
- }
+ /* Has the page moved or been split? */
+ if (unlikely(folio != xas_reload(&xas))) {
+ folio_put(folio);
+ break;
+ }
- if (*next && (page->index != *next)) {
- /* Not next consecutive page */
- unlock_page(page);
- break;
- }
+ if (!folio_trylock(folio)) {
+ folio_put(folio);
+ break;
+ }
+ if (!folio_test_dirty(folio) || folio_test_writeback(folio)) {
+ folio_unlock(folio);
+ folio_put(folio);
+ break;
+ }
- if (wbc->sync_mode != WB_SYNC_NONE)
- wait_on_page_writeback(page);
+ psize = folio_size(folio);
+ len += psize;
+ if (len >= max_len || *_count <= 0)
+ stop = true;
- if (PageWriteback(page) ||
- !clear_page_dirty_for_io(page)) {
- unlock_page(page);
- break;
+ index += folio_nr_pages(folio);
+ if (!pagevec_add(&pvec, &folio->page))
+ break;
+ if (stop)
+ break;
}
- /*
- * This actually clears the dirty bit in the radix tree.
- * See cifs_writepage() for more commentary.
+ if (!stop)
+ xas_pause(&xas);
+ rcu_read_unlock();
+
+ /* Now, if we obtained any pages, we can shift them to being
+ * writable and mark them for caching.
*/
- set_page_writeback(page);
- if (page_offset(page) >= i_size_read(mapping->host)) {
- *done = true;
- unlock_page(page);
- end_page_writeback(page);
+ if (!pagevec_count(&pvec))
break;
- }
-
- wdata->pages[i] = page;
- *next = page->index + 1;
- ++nr_pages;
- }
-
- /* reset index to refind any pages skipped */
- if (nr_pages == 0)
- *index = wdata->pages[0]->index + 1;
-
- /* put any pages we aren't going to use */
- for (i = nr_pages; i < found_pages; i++) {
- put_page(wdata->pages[i]);
- wdata->pages[i] = NULL;
- }
-
- return nr_pages;
-}
-static int
-wdata_send_pages(struct cifs_writedata *wdata, unsigned int nr_pages,
- struct address_space *mapping, struct writeback_control *wbc)
-{
- int rc;
+ for (i = 0; i < pagevec_count(&pvec); i++) {
+ folio = page_folio(pvec.pages[i]);
+ if (!folio_clear_dirty_for_io(folio))
+ BUG();
+ if (folio_start_writeback(folio))
+ BUG();
- wdata->sync_mode = wbc->sync_mode;
- wdata->nr_pages = nr_pages;
- wdata->offset = page_offset(wdata->pages[0]);
- wdata->pagesz = PAGE_SIZE;
- wdata->tailsz = min(i_size_read(mapping->host) -
- page_offset(wdata->pages[nr_pages - 1]),
- (loff_t)PAGE_SIZE);
- wdata->bytes = ((nr_pages - 1) * PAGE_SIZE) + wdata->tailsz;
- wdata->pid = wdata->cfile->pid;
-
- rc = adjust_credits(wdata->server, &wdata->credits, wdata->bytes);
- if (rc)
- return rc;
+ *_count -= folio_nr_pages(folio);
+ folio_unlock(folio);
+ }
- if (wdata->cfile->invalidHandle)
- rc = -EAGAIN;
- else
- rc = wdata->server->ops->async_writev(wdata,
- cifs_writedata_release);
+ pagevec_release(&pvec);
+ cond_resched();
+ } while (!stop);
- return rc;
+ *_len = len;
}
-static int cifs_writepages(struct address_space *mapping,
- struct writeback_control *wbc)
+/*
+ * Write back the locked page and any subsequent non-locked dirty pages.
+ */
+static ssize_t cifs_write_back_from_locked_folio(struct address_space *mapping,
+ struct writeback_control *wbc,
+ struct folio *folio,
+ loff_t start, loff_t end)
{
struct inode *inode = mapping->host;
- struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
struct TCP_Server_Info *server;
- bool done = false, scanned = false, range_whole = false;
- pgoff_t end, index;
struct cifs_writedata *wdata;
+ struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
+ struct cifs_credits credits_on_stack;
+ struct cifs_credits *credits = &credits_on_stack;
struct cifsFileInfo *cfile = NULL;
- int rc = 0;
- int saved_rc = 0;
- unsigned int xid;
+ unsigned int xid, wsize, len, max_len;
+ loff_t i_size = i_size_read(inode);
+ long count = wbc->nr_to_write;
+ int rc;
- /*
- * If wsize is smaller than the page cache size, default to writing
- * one page at a time via cifs_writepage
- */
- if (cifs_sb->ctx->wsize < PAGE_SIZE)
- return generic_writepages(mapping, wbc);
+ if (folio_start_writeback(folio))
+ BUG();
+
+ count -= folio_nr_pages(folio);
xid = get_xid();
- if (wbc->range_cyclic) {
- index = mapping->writeback_index; /* Start from prev offset */
- end = -1;
- } else {
- index = wbc->range_start >> PAGE_SHIFT;
- end = wbc->range_end >> PAGE_SHIFT;
- if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
- range_whole = true;
- scanned = true;
- }
server = cifs_pick_channel(cifs_sb_master_tcon(cifs_sb)->ses);
-retry:
- while (!done && index <= end) {
- unsigned int i, nr_pages, found_pages, wsize;
- pgoff_t next = 0, tofind, saved_index = index;
- struct cifs_credits credits_on_stack;
- struct cifs_credits *credits = &credits_on_stack;
- int get_file_rc = 0;
+ rc = cifs_get_writable_file(CIFS_I(inode), FIND_WR_ANY, &cfile);
+ if (rc) {
+ cifs_dbg(VFS, "No writable handle in writepages rc=%d\n", rc);
+ goto err_xid;
+ }
- if (cfile)
- cifsFileInfo_put(cfile);
+ rc = server->ops->wait_mtu_credits(server, cifs_sb->ctx->wsize,
+ &wsize, credits);
+ if (rc != 0)
+ goto err_close;
- rc = cifs_get_writable_file(CIFS_I(inode), FIND_WR_ANY, &cfile);
+ wdata = cifs_writedata_alloc(cifs_writev_complete);
+ if (!wdata) {
+ rc = -ENOMEM;
+ goto err_uncredit;
+ }
- /* in case of an error store it to return later */
- if (rc)
- get_file_rc = rc;
+ wdata->sync_mode = wbc->sync_mode;
+ wdata->offset = folio_pos(folio);
+ wdata->pid = wdata->cfile->pid;
+ wdata->credits = credits_on_stack;
+ wdata->cfile = cfile;
+ wdata->server = server;
+ cfile = NULL;
+
+ /* Find all consecutive lockable dirty pages, stopping when we find a
+ * page that is not immediately lockable, is not dirty or is missing,
+ * or we reach the end of the range.
+ */
+ if (start < i_size) {
+ /* Trim the write to the EOF; the extra data is ignored. Also
+ * put an upper limit on the size of a single storedata op.
+ */
+ max_len = wsize;
+ max_len = min_t(unsigned long long, max_len, end - start + 1);
+ max_len = min_t(unsigned long long, max_len, i_size - start);
+
+ if (len < max_len)
+ cifs_extend_writeback(mapping, &count, start,
+ max_len, &len);
+ len = min_t(loff_t, len, max_len);
+ }
- rc = server->ops->wait_mtu_credits(server, cifs_sb->ctx->wsize,
- &wsize, credits);
- if (rc != 0) {
- done = true;
- break;
- }
+ wdata->bytes = len;
- tofind = min((wsize / PAGE_SIZE) - 1, end - index) + 1;
+ /* We now have a contiguous set of dirty pages, each with writeback
+ * set; the first page is still locked at this point, but all the rest
+ * have been unlocked.
+ */
+ folio_unlock(folio);
- wdata = wdata_alloc_and_fillpages(tofind, mapping, end, &index,
- &found_pages);
- if (!wdata) {
- rc = -ENOMEM;
- done = true;
- add_credits_and_wake_if(server, credits, 0);
- break;
- }
+ if (start < i_size) {
+ iov_iter_xarray(&wdata->iter, WRITE, &mapping->i_pages, start, len);
- if (found_pages == 0) {
- kref_put(&wdata->refcount, cifs_writedata_release);
- add_credits_and_wake_if(server, credits, 0);
- break;
- }
+ rc = adjust_credits(wdata->server, &wdata->credits, wdata->bytes);
+ if (rc)
+ goto err_wdata;
- nr_pages = wdata_prepare_pages(wdata, found_pages, mapping, wbc,
- end, &index, &next, &done);
+ if (wdata->cfile->invalidHandle)
+ rc = -EAGAIN;
+ else
+ rc = wdata->server->ops->async_writev(wdata,
+ cifs_writedata_release);
+ } else {
+ /* The dirty region was entirely beyond the EOF. */
+ rc = 0;
+ }
- /* nothing to write? */
- if (nr_pages == 0) {
- kref_put(&wdata->refcount, cifs_writedata_release);
- add_credits_and_wake_if(server, credits, 0);
- continue;
- }
+err_wdata:
+ kref_put(&wdata->refcount, cifs_writedata_release);
+err_uncredit:
+ add_credits_and_wake_if(server, credits, 0);
+err_close:
+ if (cfile)
+ cifsFileInfo_put(cfile);
+err_xid:
+ free_xid(xid);
+ if (rc == 0) {
+ cifs_pages_written_back(inode, start, len);
+ wbc->nr_to_write = count;
+ } else if (is_retryable_error(rc)) {
+ cifs_pages_write_redirty(inode, start, len);
+ } else {
+ cifs_pages_write_failed(inode, start, len);
+ mapping_set_error(mapping, rc);
+ }
+ /* Indication to update ctime and mtime as close is deferred */
+ set_bit(CIFS_INO_MODIFIED_ATTR, &CIFS_I(inode)->flags);
+ return rc;
+}
- wdata->credits = credits_on_stack;
- wdata->cfile = cfile;
- wdata->server = server;
- cfile = NULL;
+/*
+ * write a region of pages back to the server
+ */
+static int cifs_writepages_region(struct address_space *mapping,
+ struct writeback_control *wbc,
+ loff_t start, loff_t end, loff_t *_next)
+{
+ struct folio *folio;
+ struct page *head_page;
+ ssize_t ret;
+ int n;
- if (!wdata->cfile) {
- cifs_dbg(VFS, "No writable handle in writepages rc=%d\n",
- get_file_rc);
- if (is_retryable_error(get_file_rc))
- rc = get_file_rc;
- else
- rc = -EBADF;
- } else
- rc = wdata_send_pages(wdata, nr_pages, mapping, wbc);
+ do {
+ pgoff_t index = start / PAGE_SIZE;
- for (i = 0; i < nr_pages; ++i)
- unlock_page(wdata->pages[i]);
+ n = find_get_pages_range_tag(mapping, &index, end / PAGE_SIZE,
+ PAGECACHE_TAG_DIRTY, 1, &head_page);
+ if (!n)
+ break;
- /* send failure -- clean up the mess */
- if (rc != 0) {
- add_credits_and_wake_if(server, &wdata->credits, 0);
- for (i = 0; i < nr_pages; ++i) {
- if (is_retryable_error(rc))
- redirty_page_for_writepage(wbc,
- wdata->pages[i]);
- else
- SetPageError(wdata->pages[i]);
- end_page_writeback(wdata->pages[i]);
- put_page(wdata->pages[i]);
+ folio = page_folio(head_page);
+ start = folio_pos(folio); /* May regress with THPs */
+
+ /* At this point we hold neither the i_pages lock nor the
+ * page lock: the page may be truncated or invalidated
+ * (changing page->mapping to NULL), or even swizzled
+ * back from swapper_space to tmpfs file mapping
+ */
+ if (wbc->sync_mode != WB_SYNC_NONE) {
+ ret = folio_lock_killable(folio);
+ if (ret < 0) {
+ folio_put(folio);
+ return ret;
+ }
+ } else {
+ if (!folio_trylock(folio)) {
+ folio_put(folio);
+ return 0;
}
- if (!is_retryable_error(rc))
- mapping_set_error(mapping, rc);
}
- kref_put(&wdata->refcount, cifs_writedata_release);
- if (wbc->sync_mode == WB_SYNC_ALL && rc == -EAGAIN) {
- index = saved_index;
+ if (folio_mapping(folio) != mapping ||
+ !folio_test_dirty(folio)) {
+ start += folio_size(folio);
+ folio_unlock(folio);
+ folio_put(folio);
continue;
}
- /* Return immediately if we received a signal during writing */
- if (is_interrupt_error(rc)) {
- done = true;
- break;
+ if (folio_test_writeback(folio)) {
+ folio_unlock(folio);
+ if (wbc->sync_mode != WB_SYNC_NONE)
+ folio_wait_writeback(folio);
+ folio_put(folio);
+ continue;
}
- if (rc != 0 && saved_rc == 0)
- saved_rc = rc;
+ if (!folio_clear_dirty_for_io(folio))
+ BUG();
- wbc->nr_to_write -= nr_pages;
- if (wbc->nr_to_write <= 0)
- done = true;
+ ret = cifs_write_back_from_locked_folio(mapping, wbc, folio, start, end);
+ folio_put(folio);
+ if (ret < 0)
+ return ret;
- index = next;
- }
+ start += ret;
+ cond_resched();
+ } while (wbc->nr_to_write > 0);
- if (!scanned && !done) {
- /*
- * We hit the last page and there is more work to be done: wrap
- * back to the start of the file
- */
- scanned = true;
- index = 0;
- goto retry;
- }
+ *_next = start;
+ return 0;
+}
- if (saved_rc != 0)
- rc = saved_rc;
+/*
+ * Write some of the pending data back to the server
+ */
+static int cifs_writepages(struct address_space *mapping,
+ struct writeback_control *wbc)
+{
+ loff_t start, next;
+ int ret;
- if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
- mapping->writeback_index = index;
+ /* We have to be careful as we can end up racing with setattr()
+ * truncating the pagecache since the caller doesn't take a lock here
+ * to prevent it.
+ */
- if (cfile)
- cifsFileInfo_put(cfile);
- free_xid(xid);
- /* Indication to update ctime and mtime as close is deferred */
- set_bit(CIFS_INO_MODIFIED_ATTR, &CIFS_I(inode)->flags);
- return rc;
+ if (wbc->range_cyclic) {
+ start = mapping->writeback_index * PAGE_SIZE;
+ ret = cifs_writepages_region(mapping, wbc, start, LLONG_MAX, &next);
+ if (ret == 0) {
+ mapping->writeback_index = next / PAGE_SIZE;
+ if (start > 0 && wbc->nr_to_write > 0) {
+ ret = cifs_writepages_region(mapping, wbc, 0,
+ start, &next);
+ if (ret == 0)
+ mapping->writeback_index =
+ next / PAGE_SIZE;
+ }
+ }
+ } else if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX) {
+ ret = cifs_writepages_region(mapping, wbc, 0, LLONG_MAX, &next);
+ if (wbc->nr_to_write > 0 && ret == 0)
+ mapping->writeback_index = next / PAGE_SIZE;
+ } else {
+ ret = cifs_writepages_region(mapping, wbc,
+ wbc->range_start, wbc->range_end, &next);
+ }
+
+ return ret;
}
static int
@@ -2790,47 +2829,6 @@ int cifs_flush(struct file *file, fl_owner_t id)
return rc;
}
-static int
-cifs_write_allocate_pages(struct page **pages, unsigned long num_pages)
-{
- int rc = 0;
- unsigned long i;
-
- for (i = 0; i < num_pages; i++) {
- pages[i] = alloc_page(GFP_KERNEL|__GFP_HIGHMEM);
- if (!pages[i]) {
- /*
- * save number of pages we have already allocated and
- * return with ENOMEM error
- */
- num_pages = i;
- rc = -ENOMEM;
- break;
- }
- }
-
- if (rc) {
- for (i = 0; i < num_pages; i++)
- put_page(pages[i]);
- }
- return rc;
-}
-
-static inline
-size_t get_numpages(const size_t wsize, const size_t len, size_t *cur_len)
-{
- size_t num_pages;
- size_t clen;
-
- clen = min_t(const size_t, len, wsize);
- num_pages = DIV_ROUND_UP(clen, PAGE_SIZE);
-
- if (cur_len)
- *cur_len = clen;
-
- return num_pages;
-}
-
static void
cifs_uncached_writedata_release(struct kref *refcount)
{
@@ -2839,8 +2837,11 @@ cifs_uncached_writedata_release(struct kref *refcount)
struct cifs_writedata, refcount);
kref_put(&wdata->ctx->refcount, cifs_aio_ctx_release);
- for (i = 0; i < wdata->nr_pages; i++)
- put_page(wdata->pages[i]);
+ if (wdata->bv) {
+ for (i = 0; i < wdata->bv_count; i++)
+ if (wdata->bv[i].bv_page)
+ put_page(wdata->bv[i].bv_page);
+ }
cifs_writedata_release(refcount);
}
@@ -2866,48 +2867,6 @@ cifs_uncached_writev_complete(struct work_struct *work)
kref_put(&wdata->refcount, cifs_uncached_writedata_release);
}
-static int
-wdata_fill_from_iovec(struct cifs_writedata *wdata, struct iov_iter *from,
- size_t *len, unsigned long *num_pages)
-{
- size_t save_len, copied, bytes, cur_len = *len;
- unsigned long i, nr_pages = *num_pages;
-
- save_len = cur_len;
- for (i = 0; i < nr_pages; i++) {
- bytes = min_t(const size_t, cur_len, PAGE_SIZE);
- copied = copy_page_from_iter(wdata->pages[i], 0, bytes, from);
- cur_len -= copied;
- /*
- * If we didn't copy as much as we expected, then that
- * may mean we trod into an unmapped area. Stop copying
- * at that point. On the next pass through the big
- * loop, we'll likely end up getting a zero-length
- * write and bailing out of it.
- */
- if (copied < bytes)
- break;
- }
- cur_len = save_len - cur_len;
- *len = cur_len;
-
- /*
- * If we have no data to send, then that probably means that
- * the copy above failed altogether. That's most likely because
- * the address in the iovec was bogus. Return -EFAULT and let
- * the caller free anything we allocated and bail out.
- */
- if (!cur_len)
- return -EFAULT;
-
- /*
- * i + 1 now represents the number of pages we actually used in
- * the copy phase above.
- */
- *num_pages = i + 1;
- return 0;
-}
-
static int
cifs_resend_wdata(struct cifs_writedata *wdata, struct list_head *wdata_list,
struct cifs_aio_ctx *ctx)
@@ -2986,14 +2945,11 @@ cifs_write_from_iter(loff_t offset, size_t len, struct iov_iter *from,
{
int rc = 0;
size_t cur_len;
- unsigned long nr_pages, num_pages, i;
struct cifs_writedata *wdata;
struct iov_iter saved_from = *from;
loff_t saved_offset = offset;
pid_t pid;
struct TCP_Server_Info *server;
- struct page **pagevec;
- size_t start;
unsigned int xid;
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
@@ -3024,95 +2980,30 @@ cifs_write_from_iter(loff_t offset, size_t len, struct iov_iter *from,
cur_len = min_t(const size_t, len, wsize);
- if (ctx->direct_io) {
- ssize_t result;
-
- result = iov_iter_get_pages_alloc(
- from, &pagevec, cur_len, &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, iov_iter_type(from),
- from->iov_offset, from->count);
- dump_stack();
-
- rc = result;
- add_credits_and_wake_if(server, credits, 0);
- 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;
- }
-
-
- 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;
- }
-
- rc = cifs_write_allocate_pages(wdata->pages, nr_pages);
- if (rc) {
- kvfree(wdata->pages);
- 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]);
- kvfree(wdata->pages);
- 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 = cifs_writedata_alloc(cifs_uncached_writev_complete);
+ if (!wdata) {
+ rc = -ENOMEM;
+ add_credits_and_wake_if(server, credits, 0);
+ break;
}
wdata->sync_mode = WB_SYNC_ALL;
- wdata->nr_pages = nr_pages;
wdata->offset = (__u64)offset;
wdata->cfile = cifsFileInfo_get(open_file);
wdata->server = server;
wdata->pid = pid;
wdata->bytes = cur_len;
- wdata->pagesz = PAGE_SIZE;
wdata->credits = credits_on_stack;
wdata->ctx = ctx;
kref_get(&ctx->refcount);
+ if (ctx->direct_io) {
+ wdata->bv_count = extract_iter_to_iter(&ctx->iter, &wdata->iter,
+ &wdata->bv);
+ cur_len = iov_iter_count(&wdata->iter);
+ iov_iter_advance(&ctx->iter, cur_len);
+ }
+
rc = adjust_credits(server, &wdata->credits, wdata->bytes);
if (!rc) {
@@ -3429,13 +3320,12 @@ cifs_strict_writev(struct kiocb *iocb, struct iov_iter *from)
}
static struct cifs_readdata *
-cifs_readdata_direct_alloc(struct page **pages, work_func_t complete)
+cifs_readdata_alloc(work_func_t complete)
{
struct cifs_readdata *rdata;
rdata = kzalloc(sizeof(*rdata), GFP_KERNEL);
if (rdata != NULL) {
- rdata->pages = pages;
kref_init(&rdata->refcount);
INIT_LIST_HEAD(&rdata->list);
init_completion(&rdata->done);
@@ -3445,22 +3335,6 @@ cifs_readdata_direct_alloc(struct page **pages, work_func_t complete)
return rdata;
}
-static struct cifs_readdata *
-cifs_readdata_alloc(unsigned int nr_pages, work_func_t complete)
-{
- struct page **pages =
- kcalloc(nr_pages, sizeof(struct page *), GFP_KERNEL);
- struct cifs_readdata *ret = NULL;
-
- if (pages) {
- ret = cifs_readdata_direct_alloc(pages, complete);
- if (!ret)
- kfree(pages);
- }
-
- return ret;
-}
-
void
cifs_readdata_release(struct kref *refcount)
{
@@ -3475,37 +3349,9 @@ cifs_readdata_release(struct kref *refcount)
if (rdata->cfile)
cifsFileInfo_put(rdata->cfile);
- kvfree(rdata->pages);
kfree(rdata);
}
-static int
-cifs_read_allocate_pages(struct cifs_readdata *rdata, unsigned int nr_pages)
-{
- int rc = 0;
- struct page *page;
- unsigned int i;
-
- for (i = 0; i < nr_pages; i++) {
- page = alloc_page(GFP_KERNEL|__GFP_HIGHMEM);
- if (!page) {
- rc = -ENOMEM;
- break;
- }
- rdata->pages[i] = page;
- }
-
- if (rc) {
- unsigned int nr_page_failed = i;
-
- for (i = 0; i < nr_page_failed; i++) {
- put_page(rdata->pages[i]);
- rdata->pages[i] = NULL;
- }
- }
- return rc;
-}
-
static void
cifs_uncached_readdata_release(struct kref *refcount)
{
@@ -3514,12 +3360,15 @@ cifs_uncached_readdata_release(struct kref *refcount)
unsigned int i;
kref_put(&rdata->ctx->refcount, cifs_aio_ctx_release);
- for (i = 0; i < rdata->nr_pages; i++) {
- put_page(rdata->pages[i]);
+ if (rdata->bv) {
+ for (i = 0; i < rdata->bv_count; i++)
+ if (rdata->bv[i].bv_page)
+ put_page(rdata->bv[i].bv_page);
}
cifs_readdata_release(refcount);
}
+#if 0
/**
* cifs_readdata_to_iov - copy data from pages in response to an iovec
* @rdata: the readdata response with list of pages holding data
@@ -3553,6 +3402,7 @@ cifs_readdata_to_iov(struct cifs_readdata *rdata, struct iov_iter *iter)
}
return remaining ? -EFAULT : 0;
}
+#endif
static void collect_uncached_read_data(struct cifs_aio_ctx *ctx);
@@ -3568,6 +3418,7 @@ cifs_uncached_readv_complete(struct work_struct *work)
kref_put(&rdata->refcount, cifs_uncached_readdata_release);
}
+#if 0
static int cifs_resend_rdata(struct cifs_readdata *rdata,
struct list_head *rdata_list,
struct cifs_aio_ctx *ctx)
@@ -3639,6 +3490,7 @@ static int cifs_resend_rdata(struct cifs_readdata *rdata,
kref_put(&rdata->refcount, cifs_uncached_readdata_release);
return rc;
}
+#endif
static int
cifs_send_async_read(loff_t offset, size_t len, struct cifsFileInfo *open_file,
@@ -3646,14 +3498,13 @@ cifs_send_async_read(loff_t offset, size_t len, struct cifsFileInfo *open_file,
struct cifs_aio_ctx *ctx)
{
struct cifs_readdata *rdata;
- unsigned int npages, rsize;
+ unsigned int rsize;
struct cifs_credits credits_on_stack;
struct cifs_credits *credits = &credits_on_stack;
size_t cur_len;
int rc;
pid_t pid;
struct TCP_Server_Info *server;
- size_t start;
struct iov_iter direct_iov = ctx->iter;
server = cifs_pick_channel(tlink_tcon(open_file->tlink)->ses);
@@ -3682,59 +3533,28 @@ cifs_send_async_read(loff_t offset, size_t len, struct cifsFileInfo *open_file,
cur_len = min_t(const size_t, len, rsize);
- if (ctx->direct_io) {
- 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;
- }
-
- rc = cifs_read_allocate_pages(rdata, npages);
- if (rc) {
- kvfree(rdata->pages);
- kfree(rdata);
- add_credits_and_wake_if(server, credits, 0);
- break;
- }
-
- rdata->tailsz = PAGE_SIZE;
+ rdata = cifs_readdata_alloc(cifs_uncached_readv_complete);
+ if (!rdata) {
+ add_credits_and_wake_if(server, credits, 0);
+ rc = -ENOMEM;
+ break;
}
rdata->server = server;
rdata->cfile = cifsFileInfo_get(open_file);
- rdata->nr_pages = ctx->npages;
rdata->offset = offset;
rdata->bytes = cur_len;
rdata->pid = pid;
- rdata->pagesz = PAGE_SIZE;
rdata->credits = credits_on_stack;
rdata->ctx = ctx;
rdata->iter = ctx->iter;
kref_get(&ctx->refcount);
+ if (ctx->direct_io) {
+ cur_len = iov_iter_count(&ctx->iter);
+ iov_iter_advance(&direct_iov, cur_len);
+ }
+
rc = adjust_credits(server, &rdata->credits, rdata->bytes);
if (!rc) {
@@ -3768,11 +3588,9 @@ collect_uncached_read_data(struct cifs_aio_ctx *ctx)
{
struct cifs_readdata *rdata, *tmp;
struct iov_iter *to = &ctx->iter;
- struct cifs_sb_info *cifs_sb;
+ //struct cifs_sb_info *cifs_sb = CIFS_SB(ctx->cfile->dentry->d_sb);
int rc;
- cifs_sb = CIFS_SB(ctx->cfile->dentry->d_sb);
-
mutex_lock(&ctx->aio_mutex);
if (list_empty(&ctx->list)) {
@@ -3782,7 +3600,7 @@ collect_uncached_read_data(struct cifs_aio_ctx *ctx)
rc = ctx->rc;
/* the loop below should proceed in the order of increasing offsets */
-again:
+//again:
list_for_each_entry_safe(rdata, tmp, &ctx->list, list) {
if (!rc) {
if (!try_wait_for_completion(&rdata->done)) {
@@ -3790,6 +3608,7 @@ collect_uncached_read_data(struct cifs_aio_ctx *ctx)
return;
}
+#if 0 // TODO
if (rdata->result == -EAGAIN) {
/* resend call if it's a retryable error */
struct list_head tmp_list;
@@ -3840,6 +3659,9 @@ collect_uncached_read_data(struct cifs_aio_ctx *ctx)
rc = rdata->result;
else if (!ctx->direct_io)
rc = cifs_readdata_to_iov(rdata, to);
+#else
+ rc = rdata->result;
+#endif
/* if there was a short read -- discard anything left */
if (rdata->got_bytes && rdata->got_bytes < rdata->bytes)
@@ -4135,7 +3957,7 @@ static void cifs_req_issue_op(struct netfs_read_subrequest *subreq)
if (rc)
goto out;
- rdata = cifs_readdata_alloc(0, NULL);
+ rdata = cifs_readdata_alloc(NULL);
if (!rdata) {
add_credits_and_wake_if(server, credits, 0);
rc = -ENOMEM;
@@ -4149,8 +3971,6 @@ static void cifs_req_issue_op(struct netfs_read_subrequest *subreq)
rdata->offset = subreq->start + subreq->transferred;
rdata->bytes = subreq->len - subreq->transferred;
rdata->pid = pid;
- rdata->pagesz = PAGE_SIZE;
- rdata->tailsz = PAGE_SIZE;
rdata->credits = credits_on_stack;
iov_iter_xarray(&rdata->iter, READ, &rreq->mapping->i_pages,
diff --git a/fs/cifs/misc.c b/fs/cifs/misc.c
index ece7fc8a7740..2c012fef9da8 100644
--- a/fs/cifs/misc.c
+++ b/fs/cifs/misc.c
@@ -1032,25 +1032,6 @@ cifs_free_hash(struct crypto_shash **shash, struct sdesc **sdesc)
*shash = NULL;
}
-/**
- * rqst_page_get_length - obtain the length and offset for a page in smb_rqst
- * @rqst: The request descriptor
- * @page: The index of the page to query
- * @len: Where to store the length for this page:
- * @offset: Where to store the offset for this page
- */
-void rqst_page_get_length(struct smb_rqst *rqst, unsigned int page,
- unsigned int *len, unsigned int *offset)
-{
- *len = rqst->rq_pagesz;
- *offset = (page == 0) ? rqst->rq_offset : 0;
-
- if (rqst->rq_npages == 1 || page == rqst->rq_npages-1)
- *len = rqst->rq_tailsz;
- else if (page == 0)
- *len = rqst->rq_pagesz - rqst->rq_offset;
-}
-
void extract_unc_hostname(const char *unc, const char **h, size_t *len)
{
const char *end;
diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index a5ce04331613..fc07cd353b81 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -4406,6 +4406,20 @@ static inline void smb2_sg_set_buf(struct scatterlist *sg, const void *buf,
sg_set_page(sg, addr, buflen, offset_in_page(buf));
}
+struct cifs_init_sg_priv {
+ struct scatterlist *sg;
+ unsigned int idx;
+};
+
+static ssize_t cifs_init_sg_scan(struct iov_iter *i, const void *p,
+ size_t len, size_t off, void *_priv)
+{
+ struct cifs_init_sg_priv *priv = _priv;
+
+ smb2_sg_set_buf(&priv->sg[priv->idx++], p, len);
+ return 0;
+}
+
/* Assumes the first rqst has a transform header as the first iov.
* I.e.
* rqst[0].rq_iov[0] is transform header
@@ -4415,43 +4429,44 @@ static inline void smb2_sg_set_buf(struct scatterlist *sg, const void *buf,
static struct scatterlist *
init_sg(int num_rqst, struct smb_rqst *rqst, u8 *sign)
{
+ struct cifs_init_sg_priv priv;
unsigned int sg_len;
- struct scatterlist *sg;
unsigned int i;
unsigned int j;
- unsigned int idx = 0;
+ ssize_t rc;
int skip;
sg_len = 1;
- for (i = 0; i < num_rqst; i++)
- sg_len += rqst[i].rq_nvec + rqst[i].rq_npages;
+ for (i = 0; i < num_rqst; i++) {
+ sg_len += rqst[i].rq_nvec;
+ sg_len += iov_iter_npages(&rqst[i].rq_iter, INT_MAX);
+ }
- sg = kmalloc_array(sg_len, sizeof(struct scatterlist), GFP_KERNEL);
- if (!sg)
+ priv.sg = kmalloc_array(sg_len, sizeof(struct scatterlist), GFP_KERNEL);
+ if (!priv.sg)
return NULL;
- sg_init_table(sg, sg_len);
+ sg_init_table(priv.sg, sg_len);
for (i = 0; i < num_rqst; i++) {
+ struct iov_iter *iter = &rqst[i].rq_iter;
+
for (j = 0; j < rqst[i].rq_nvec; j++) {
/*
* The first rqst has a transform header where the
* first 20 bytes are not part of the encrypted blob
*/
skip = (i == 0) && (j == 0) ? 20 : 0;
- smb2_sg_set_buf(&sg[idx++],
+ smb2_sg_set_buf(&priv.sg[priv.idx++],
rqst[i].rq_iov[j].iov_base + skip,
rqst[i].rq_iov[j].iov_len - skip);
- }
-
- for (j = 0; j < rqst[i].rq_npages; j++) {
- unsigned int len, offset;
-
- rqst_page_get_length(&rqst[i], j, &len, &offset);
- sg_set_page(&sg[idx++], rqst[i].rq_pages[j], len, offset);
}
+
+ rc = iov_iter_scan(iter, iov_iter_count(iter),
+ cifs_init_sg_scan, &priv);
+ WARN_ON(rc < 0);
}
- smb2_sg_set_buf(&sg[idx], sign, SMB2_SIGNATURE_SIZE);
- return sg;
+ smb2_sg_set_buf(&priv.sg[priv.idx], sign, SMB2_SIGNATURE_SIZE);
+ return priv.sg;
}
static int
@@ -4588,18 +4603,30 @@ crypt_message(struct TCP_Server_Info *server, int num_rqst,
return rc;
}
+/*
+ * Clear a read buffer, discarding the folios which have XA_MARK_0 set.
+ */
+static void netfs_clear_buffer(struct xarray *buffer)
+{
+ struct folio *folio;
+ XA_STATE(xas, buffer, 0);
+
+ rcu_read_lock();
+ xas_for_each_marked(&xas, folio, ULONG_MAX, XA_MARK_0) {
+ folio_put(folio);
+ }
+ rcu_read_unlock();
+ xa_destroy(buffer);
+}
+
void
smb3_free_compound_rqst(int num_rqst, struct smb_rqst *rqst)
{
- int i, j;
+ int i;
- for (i = 0; i < num_rqst; i++) {
- if (rqst[i].rq_pages) {
- for (j = rqst[i].rq_npages - 1; j >= 0; j--)
- put_page(rqst[i].rq_pages[j]);
- kfree(rqst[i].rq_pages);
- }
- }
+ for (i = 0; i < num_rqst; i++)
+ if (!xa_empty(&rqst[i].rq_buffer))
+ netfs_clear_buffer(&rqst[i].rq_buffer);
}
/*
@@ -4619,50 +4646,37 @@ static int
smb3_init_transform_rq(struct TCP_Server_Info *server, int num_rqst,
struct smb_rqst *new_rq, struct smb_rqst *old_rq)
{
- struct page **pages;
struct smb2_transform_hdr *tr_hdr = new_rq[0].rq_iov[0].iov_base;
- unsigned int npages;
+ struct page *page;
unsigned int orig_len = 0;
int i, j;
int rc = -ENOMEM;
for (i = 1; i < num_rqst; i++) {
- npages = old_rq[i - 1].rq_npages;
- pages = kmalloc_array(npages, sizeof(struct page *),
- GFP_KERNEL);
- if (!pages)
- goto err_free;
-
- new_rq[i].rq_pages = pages;
- new_rq[i].rq_npages = npages;
- new_rq[i].rq_offset = old_rq[i - 1].rq_offset;
- new_rq[i].rq_pagesz = old_rq[i - 1].rq_pagesz;
- new_rq[i].rq_tailsz = old_rq[i - 1].rq_tailsz;
- new_rq[i].rq_iov = old_rq[i - 1].rq_iov;
- new_rq[i].rq_nvec = old_rq[i - 1].rq_nvec;
-
- orig_len += smb_rqst_len(server, &old_rq[i - 1]);
+ struct smb_rqst *old = &old_rq[i - 1];
+ struct smb_rqst *new = &new_rq[i];
+ struct xarray *buffer = &new->rq_buffer;
+ unsigned int npages;
+ size_t size = iov_iter_count(&old->rq_iter), seg;
- for (j = 0; j < npages; j++) {
- pages[j] = alloc_page(GFP_KERNEL|__GFP_HIGHMEM);
- if (!pages[j])
- goto err_free;
- }
+ orig_len += size;
+ xa_init(buffer);
- /* copy pages form the old */
+ npages = DIV_ROUND_UP(size, PAGE_SIZE);
for (j = 0; j < npages; j++) {
- char *dst, *src;
- unsigned int offset, len;
-
- rqst_page_get_length(&new_rq[i], j, &len, &offset);
-
- dst = (char *) kmap(new_rq[i].rq_pages[j]) + offset;
- src = (char *) kmap(old_rq[i - 1].rq_pages[j]) + offset;
+ page = alloc_page(GFP_KERNEL|__GFP_HIGHMEM);
+ if (!xa_store(buffer, j, page, GFP_KERNEL))
+ goto err_free;
- memcpy(dst, src, len);
- kunmap(new_rq[i].rq_pages[j]);
- kunmap(old_rq[i - 1].rq_pages[j]);
+ seg = min(size, PAGE_SIZE);
+ if (copy_page_from_iter(page, 0, seg, &old->rq_iter) != seg) {
+ rc = -EFAULT;
+ goto err_free;
+ }
}
+
+ new->rq_iov = old->rq_iov;
+ new->rq_nvec = old->rq_nvec;
}
/* fill the 1st iov with a transform header */
@@ -4705,10 +4719,6 @@ decrypt_raw_data(struct TCP_Server_Info *server, char *buf,
rqst.rq_iov = iov;
rqst.rq_nvec = 2;
- rqst.rq_pages = pages;
- rqst.rq_npages = npages;
- rqst.rq_pagesz = PAGE_SIZE;
- rqst.rq_tailsz = (page_data_size % PAGE_SIZE) ? : PAGE_SIZE;
rc = crypt_message(server, 1, &rqst, 0);
cifs_dbg(FYI, "Decrypt message returned %d\n", rc);
diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index ea2f8a2d9e57..4d43e06c5a32 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -4014,11 +4014,7 @@ smb2_readv_callback(struct mid_q_entry *mid)
struct cifs_credits credits = { .value = 0, .instance = 0 };
struct smb_rqst rqst = { .rq_iov = &rdata->iov[1],
.rq_nvec = 1,
- .rq_pages = rdata->pages,
- .rq_offset = rdata->page_offset,
- .rq_npages = rdata->nr_pages,
- .rq_pagesz = rdata->pagesz,
- .rq_tailsz = rdata->tailsz };
+ .rq_iter = rdata->iter };
WARN_ONCE(rdata->server != mid->server,
"rdata server %p != mid server %p",
@@ -4425,11 +4421,7 @@ smb2_async_writev(struct cifs_writedata *wdata,
rqst.rq_iov = iov;
rqst.rq_nvec = 1;
- rqst.rq_pages = wdata->pages;
- rqst.rq_offset = wdata->page_offset;
- rqst.rq_npages = wdata->nr_pages;
- rqst.rq_pagesz = wdata->pagesz;
- rqst.rq_tailsz = wdata->tailsz;
+ rqst.rq_iter = wdata->iter;
#ifdef CONFIG_CIFS_SMB_DIRECT
if (wdata->mr) {
iov[0].iov_len += sizeof(struct smbd_buffer_descriptor_v1);
diff --git a/fs/cifs/transport.c b/fs/cifs/transport.c
index 61ea3d3f95b4..2c4574ae832e 100644
--- a/fs/cifs/transport.c
+++ b/fs/cifs/transport.c
@@ -276,26 +276,7 @@ smb_rqst_len(struct TCP_Server_Info *server, struct smb_rqst *rqst)
for (i = 0; i < nvec; i++)
buflen += iov[i].iov_len;
- /*
- * Add in the page array if there is one. The caller needs to make
- * sure rq_offset and rq_tailsz are set correctly. If a buffer of
- * multiple pages ends at page boundary, rq_tailsz needs to be set to
- * PAGE_SIZE.
- */
- if (rqst->rq_npages) {
- if (rqst->rq_npages == 1)
- buflen += rqst->rq_tailsz;
- else {
- /*
- * If there is more than one page, calculate the
- * buffer length based on rq_offset and rq_tailsz
- */
- buflen += rqst->rq_pagesz * (rqst->rq_npages - 1) -
- rqst->rq_offset;
- buflen += rqst->rq_tailsz;
- }
- }
-
+ buflen += iov_iter_count(&rqst->rq_iter);
return buflen;
}
@@ -382,22 +363,12 @@ __smb_send_rqst(struct TCP_Server_Info *server, int num_rqst,
total_len += sent;
- /* now walk the page array and send each page in it */
- for (i = 0; i < rqst[j].rq_npages; i++) {
- struct bio_vec bvec;
-
- bvec.bv_page = rqst[j].rq_pages[i];
- rqst_page_get_length(&rqst[j], i, &bvec.bv_len,
- &bvec.bv_offset);
-
- iov_iter_bvec(&smb_msg.msg_iter, WRITE,
- &bvec, 1, bvec.bv_len);
- rc = smb_send_kvec(server, &smb_msg, &sent);
- if (rc < 0)
- break;
+ smb_msg.msg_iter = rqst[j].rq_iter;
+ rc = smb_send_kvec(server, &smb_msg, &sent);
+ if (rc < 0)
+ break;
- total_len += sent;
- }
+ total_len += sent;
}
unmask:
diff --git a/include/linux/uio.h b/include/linux/uio.h
index 931528bc2eab..c6f84416425e 100644
--- a/include/linux/uio.h
+++ b/include/linux/uio.h
@@ -254,6 +254,10 @@ int iov_iter_npages(const struct iov_iter *i, int maxpages);
void iov_iter_restore(struct iov_iter *i, struct iov_iter_state *state);
const void *dup_iter(struct iov_iter *new, struct iov_iter *old, gfp_t flags);
+ssize_t iov_iter_scan(struct iov_iter *i, size_t bytes,
+ ssize_t (*scanner)(struct iov_iter *i, const void *p,
+ size_t len, size_t off, void *priv),
+ void *priv);
static inline size_t iov_iter_count(const struct iov_iter *i)
{
diff --git a/lib/iov_iter.c b/lib/iov_iter.c
index cebfdb617fd8..3cd53e7ed5b9 100644
--- a/lib/iov_iter.c
+++ b/lib/iov_iter.c
@@ -1790,6 +1790,48 @@ ssize_t extract_iter_to_iter(struct iov_iter *orig,
}
EXPORT_SYMBOL(extract_iter_to_iter);
+/**
+ * iov_iter_scan - Scan a source iter
+ * @i: The iterator to scan
+ * @bytes: The amount of data to scan
+ * @scanner: The function to call for each bit
+ * @priv: Private data to pass to the scanner function
+ *
+ * Scan a source iterator (WRITE-type), passing each segment to the scanner
+ * function. If the scanner returns an error at any time, scanning stops and
+ * the error is returned, otherwise the sum of the scanner results is returned.
+ */
+ssize_t iov_iter_scan(struct iov_iter *i, size_t bytes,
+ ssize_t (*scanner)(struct iov_iter *i, const void *p,
+ size_t len, size_t off, void *priv),
+ void *priv)
+{
+ ssize_t ret = 0, scanned = 0;
+
+ if (!bytes)
+ return 0;
+ if (WARN_ON(iov_iter_rw(i) != WRITE))
+ return 0;
+ if (iter_is_iovec(i))
+ might_fault();
+
+ iterate_and_advance(
+ i, bytes, base, len, off, ({
+ ret = scanner(i, base, len, off, priv);
+ if (ret < 0)
+ break;
+ scanned += ret;
+ }), ({
+ ret = scanner(i, base, len, off, priv);
+ if (ret < 0)
+ break;
+ scanned += ret;
+ })
+ );
+ return ret < 0 ? ret : scanned;
+}
+EXPORT_SYMBOL(iov_iter_scan);
+
size_t csum_and_copy_from_iter(void *addr, size_t bytes, __wsum *csum,
struct iov_iter *i)
{
^ permalink raw reply related [flat|nested] 8+ messages in thread