Hi Steve,
Here's a rough, but incomplete, conversion of cifs to use the revised fscache
I/O API and the netfs helper lib, but I've about hit the limit of what I can
manage to do. It's built on top of my fscache-netfs-lib branch:
https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git/log/?h=fscache-netfs-lib
Notes:
(*) I've replaced some code to discard data by reading into a big buffer with
code that uses the ITER_DISCARD iterator instead. See
cifs_discard_from_socket().
(*) I've tried to make the ordinary read use an ITER_XARRAY iterator and read
into that directly from the socket, rather than looping through a bunch
of pages. This will handle THPs and partial pages for you. However,
under some circumstances, readpages_fill_pages() would then be reading
from an iterator to an iterator, it appears. Possibly the source
iterator can be got rid of, but the code is quite complex.
(*) There's a new function, cifs_req_issue_op(), which the netfs helpers use
to issue a read on part of a request. This looks at current->tgid, but
might be running on a workqueue, so needs to get the tgid from somewhere
else if not CIFS_MOUNT_RWPIDFORWARD.
(*) cifs_readpage(), cifs_readahead() and cifs_write_begin() now go through
the helpers. cifs_readpages() is obsolete and is removed.
(*) At the completion of a read, netfs_subreq_terminated() is called. As a
future optimisation, we can add a function to do incremental advancement
of the pages, unlocking them as we go. The issue is, however, that we
have to coordinate with writing larger page lumps to the cache.
(*) The clause in cifs_write_begin() about optimising away a read when we
have an oplock needs dealing with, but I'm not sure how to fit it in.
David
---
diff --git a/fs/cifs/Kconfig b/fs/cifs/Kconfig
index fe03cbdae959..ad296c3dbd04 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_MD4
diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index 50fcb65920e8..fe5fd4bcb866 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -1283,6 +1283,7 @@ struct cifs_readdata;
/* asynchronous read support */
struct cifs_readdata {
+ struct netfs_read_subrequest *subreq;
struct kref refcount;
struct list_head list;
struct completion done;
@@ -1301,6 +1302,7 @@ 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 340ff81ee87b..f5ac4a7c1cfc 100644
--- a/fs/cifs/cifsproto.h
+++ b/fs/cifs/cifsproto.h
@@ -230,11 +230,16 @@ extern unsigned int setup_special_user_owner_ACE(struct
cifs_ace *pace);
extern void dequeue_mid(struct mid_q_entry *mid, bool malformed);
extern int cifs_read_from_socket(struct TCP_Server_Info *server, char *buf,
unsigned int to_read);
+extern ssize_t cifs_discard_from_socket(struct TCP_Server_Info *server,
+ size_t to_read);
extern int cifs_read_page_from_socket(struct TCP_Server_Info *server,
struct page *page,
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 0496934feecb..671afc822afc 100644
--- a/fs/cifs/cifssmb.c
+++ b/fs/cifs/cifssmb.c
@@ -36,6 +36,7 @@
#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"
@@ -1445,15 +1446,15 @@ 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_read_from_socket(server, server->bigbuf,
- min_t(unsigned int, remaining,
- CIFSMaxBufSize + MAX_HEADER_SIZE(server)));
+ length = cifs_discard_from_socket(server,
+ min_t(size_t, remaining,
+ CIFSMaxBufSize +
MAX_HEADER_SIZE(server)));
if (length < 0)
return length;
server->total_read += length;
@@ -1664,7 +1665,14 @@ 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);
+ kref_put(&rdata->refcount, cifs_readdata_release);
+ } else {
+ queue_work(cifsiod_wq, &rdata->work);
+ }
DeleteMidQEntry(mid);
add_credits(server, &credits, 0);
}
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 5d39129406ea..28c13602ed43 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -564,6 +564,15 @@ cifs_read_from_socket(struct TCP_Server_Info *server, char
*buf,
return cifs_readv_from_socket(server, &smb_msg);
}
+ssize_t
+cifs_discard_from_socket(struct TCP_Server_Info *server, size_t to_read)
+{
+ struct msghdr smb_msg;
+ iov_iter_discard(&smb_msg.msg_iter, READ, to_read);
+
+ return cifs_readv_from_socket(server, &smb_msg);
+}
+
int
cifs_read_page_from_socket(struct TCP_Server_Info *server, struct page *page,
unsigned int page_offset, unsigned int to_read)
@@ -575,6 +584,22 @@ 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 6d001905c8e5..c1f7ad4dbcb9 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -34,6 +34,7 @@
#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"
@@ -4006,98 +4007,6 @@ 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.
@@ -4107,7 +4016,21 @@ cifs_page_mkwrite(struct vm_fault *vmf)
{
struct page *page = vmf->page;
- lock_page(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_bit_killable(page, PG_fscache) < 0)
+ return VM_FAULT_RETRY;
+#endif
+
+ if (PageWriteback(page) &&
+ wait_on_page_bit_killable(page, PG_writeback) < 0)
+ return VM_FAULT_RETRY;
+
+ if (lock_page_killable(page) < 0)
+ return VM_FAULT_RETRY;
return VM_FAULT_LOCKED;
}
@@ -4154,39 +4077,6 @@ 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);
- }
-
- 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,
@@ -4261,8 +4151,7 @@ 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;
@@ -4288,292 +4177,179 @@ cifs_readpages_copy_into_pages(struct TCP_Server_Info
*server,
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;
+ 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;
+#warning current might 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);
-
- /*
- * 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;
+ 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);
- 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) {
+ rc = -ENOMEM;
+ add_credits_and_wake_if(server, credits, 0);
+ 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);
}
- /* Any pages that have been shown to fscache but didn't get added to
- * the pagecache must be uncached before they get returned to the
- * allocator.
- */
- cifs_fscache_readpages_cancel(mapping->host, page_list);
+ kref_put(&rdata->refcount, cifs_readdata_release);
+
+out:
free_xid(xid);
- return rc;
+ if (rc < 0)
+ netfs_subreq_terminated(subreq, rc);
}
-/*
- * cifs_readpage_worker must be called with the page pinned
- */
-static int cifs_readpage_worker(struct file *file, struct page *page,
- loff_t *poffset)
+static void cifs_init_rreq(struct netfs_read_request *rreq, struct file *file)
{
- char *read_data;
- int rc;
-
- /* Is the page cached? */
- rc = cifs_readpage_from_fscache(file_inode(file), page);
- if (rc == 0)
- goto read_complete;
+ rreq->netfs_priv = file->private_data;
+}
- read_data = kmap(page);
- /* for reads over a certain size could initiate async read ahead */
+static bool cifs_is_cache_enabled(struct inode *inode)
+{
+ struct fscache_cookie *cookie = cifs_inode_cookie(inode);
- rc = cifs_read(file, read_data, PAGE_SIZE, poffset);
+ return fscache_cookie_enabled(cookie) &&
!hlist_empty(&cookie->backing_objects);
+}
- if (rc < 0)
- goto io_error;
- else
- cifs_dbg(FYI, "Bytes read %d\n", rc);
+static int cifs_begin_cache_operation(struct netfs_read_request *rreq)
+{
+ return fscache_begin_read_operation(rreq,
cifs_inode_cookie(rreq->inode));
+}
- /* 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;
- else
- file_inode(file)->i_atime = current_time(file_inode(file));
+/*
+ * 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. The caller will then clamp it to i_size.
+ */
+static void cifs_expand_readahead(struct netfs_read_request *rreq)
+{
+ struct cifs_sb_info *cifs_sb = CIFS_SB(rreq->inode->i_sb);
+ unsigned int rsize = cifs_sb->ctx->rsize;
+ loff_t misalignment;
- if (PAGE_SIZE > rc)
- memset(read_data + rc, 0, PAGE_SIZE - rc);
+ if (rsize < PAGE_SIZE)
+ return;
- flush_dcache_page(page);
- SetPageUptodate(page);
+ if (rsize < INT_MAX)
+ rsize = roundup_pow_of_two(rsize);
+ else
+ rsize = ((unsigned int)INT_MAX + 1) / 2;
- /* send this page to the cache */
- cifs_readpage_to_fscache(file_inode(file), page);
+ misalignment = rreq->start & (rsize - 1);
+ if (misalignment) {
+ rreq->start -= misalignment;
+ rreq->len += misalignment;
+ }
- rc = 0;
+ rreq->len = round_up(rreq->len, rsize);
+}
-io_error:
- kunmap(page);
- unlock_page(page);
+static void cifs_rreq_done(struct netfs_read_request *rreq)
+{
+ struct inode *inode = rreq->inode;
-read_complete:
- return rc;
+ /* 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);
}
+const struct netfs_read_request_ops cifs_req_ops = {
+ .init_rreq = cifs_init_rreq,
+ .is_cache_enabled = cifs_is_cache_enabled,
+ .begin_cache_operation = cifs_begin_cache_operation,
+ .expand_readahead = cifs_expand_readahead,
+ .issue_op = cifs_req_issue_op,
+ .done = cifs_rreq_done,
+};
+
static int cifs_readpage(struct file *file, struct page *page)
{
loff_t offset = (loff_t)page->index << PAGE_SHIFT;
- int rc = -EACCES;
- unsigned int xid;
-
- xid = get_xid();
- if (file->private_data == NULL) {
- rc = -EBADF;
- free_xid(xid);
- return rc;
- }
+ if (!file->private_data)
+ return -EBADF;
- cifs_dbg(FYI, "readpage %p at offset %d 0x%x\n",
- page, (int)offset, (int)offset);
+ cifs_dbg(FYI, "readpage %p at offset %u 0x%x\n",
+ page, (unsigned int)offset, (int)offset);
- rc = cifs_readpage_worker(file, page, &offset);
+ return netfs_readpage(file, page, &cifs_req_ops, NULL);
+}
- free_xid(xid);
- return rc;
+static void cifs_readahead(struct readahead_control *ractl)
+{
+ netfs_readahead(ractl, &cifs_req_ops, NULL);
}
static int is_inode_writable(struct cifsInodeInfo *cifs_inode)
@@ -4625,34 +4401,21 @@ 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;
+ 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, &page, 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
@@ -4676,25 +4439,8 @@ static int cifs_write_begin(struct file *file, struct
address_space *mapping,
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 = find_subpage(page, pos / PAGE_SIZE);
return rc;
}
@@ -4703,16 +4449,23 @@ static int cifs_release_page(struct page *page, gfp_t
gfp)
if (PagePrivate(page))
return 0;
- return cifs_fscache_release_page(page, gfp);
+ /* deny if page is being written to the cache and the caller hasn't
+ * elected to wait */
+#ifdef CONFIG_CIFS_FSCACHE
+ if (PageFsCache(page)) {
+ if (!(gfp & __GFP_DIRECT_RECLAIM) || !(gfp & __GFP_FS))
+ return 0;
+ wait_on_page_fscache(page);
+ }
+#endif
+
+ return 1;
}
static void cifs_invalidate_page(struct page *page, unsigned int offset,
unsigned int length)
{
- struct cifsInodeInfo *cifsi = CIFS_I(page->mapping->host);
-
- if (offset == 0 && length == PAGE_SIZE)
- cifs_fscache_invalidate_page(page, &cifsi->vfs_inode);
+ wait_on_page_fscache(page);
}
static int cifs_launder_page(struct page *page)
@@ -4732,7 +4485,7 @@ static int cifs_launder_page(struct page *page)
if (clear_page_dirty_for_io(page))
rc = cifs_writepage_locked(page, &wbc);
- cifs_fscache_invalidate_page(page, page->mapping->host);
+ wait_on_page_fscache(page);
return rc;
}
@@ -4872,7 +4625,7 @@ static void cifs_swap_deactivate(struct file *file)
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 20d24af33ee2..4acd599d91d9 100644
--- a/fs/cifs/fscache.c
+++ b/fs/cifs/fscache.c
@@ -199,7 +199,6 @@ static void cifs_fscache_disable_inode_cookie(struct inode
*inode)
if (cifsi->fscache) {
cifs_dbg(FYI, "%s: (0x%p)\n", __func__, cifsi->fscache);
- fscache_uncache_all_inode_pages(cifsi->fscache, inode);
fscache_relinquish_cookie(cifsi->fscache, NULL, true);
cifsi->fscache = NULL;
}
@@ -229,120 +228,3 @@ void cifs_fscache_reset_inode_cookie(struct inode *inode)
__func__, cifsi->fscache, old);
}
}
-
-int cifs_fscache_release_page(struct page *page, gfp_t gfp)
-{
- if (PageFsCache(page)) {
- struct inode *inode = page->mapping->host;
- struct cifsInodeInfo *cifsi = CIFS_I(inode);
-
- cifs_dbg(FYI, "%s: (0x%p/0x%p)\n",
- __func__, page, cifsi->fscache);
- if (!fscache_maybe_release_page(cifsi->fscache, page, gfp))
- return 0;
- }
-
- return 1;
-}
-
-static void cifs_readpage_from_fscache_complete(struct page *page, void *ctx,
- int error)
-{
- cifs_dbg(FYI, "%s: (0x%p/%d)\n", __func__, page, error);
- if (!error)
- SetPageUptodate(page);
- unlock_page(page);
-}
-
-/*
- * Retrieve a page from FS-Cache
- */
-int __cifs_readpage_from_fscache(struct inode *inode, struct page *page)
-{
- int ret;
-
- cifs_dbg(FYI, "%s: (fsc:%p, p:%p, i:0x%p\n",
- __func__, CIFS_I(inode)->fscache, page, inode);
- ret = fscache_read_or_alloc_page(CIFS_I(inode)->fscache, page,
- cifs_readpage_from_fscache_complete,
- NULL,
- GFP_KERNEL);
- switch (ret) {
-
- case 0: /* page found in fscache, read submitted */
- cifs_dbg(FYI, "%s: submitted\n", __func__);
- return ret;
- case -ENOBUFS: /* page won't be cached */
- case -ENODATA: /* page not in cache */
- cifs_dbg(FYI, "%s: %d\n", __func__, ret);
- return 1;
-
- default:
- cifs_dbg(VFS, "unknown error ret = %d\n", ret);
- }
- return ret;
-}
-
-/*
- * 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)
-{
- int ret;
-
- cifs_dbg(FYI, "%s: (0x%p/%u/0x%p)\n",
- __func__, CIFS_I(inode)->fscache, *nr_pages, inode);
- ret = fscache_read_or_alloc_pages(CIFS_I(inode)->fscache, mapping,
- pages, nr_pages,
- cifs_readpage_from_fscache_complete,
- NULL,
- mapping_gfp_mask(mapping));
- switch (ret) {
- case 0: /* read submitted to the cache for all pages */
- cifs_dbg(FYI, "%s: submitted\n", __func__);
- return ret;
-
- case -ENOBUFS: /* some pages are not cached and can't be */
- case -ENODATA: /* some pages are not cached */
- cifs_dbg(FYI, "%s: no page\n", __func__);
- return 1;
-
- default:
- cifs_dbg(FYI, "unknown error ret = %d\n", ret);
- }
-
- return ret;
-}
-
-void __cifs_readpage_to_fscache(struct inode *inode, struct page *page)
-{
- struct cifsInodeInfo *cifsi = CIFS_I(inode);
- int ret;
-
- cifs_dbg(FYI, "%s: (fsc: %p, p: %p, i: %p)\n",
- __func__, cifsi->fscache, page, inode);
- ret = fscache_write_page(cifsi->fscache, page,
- cifsi->vfs_inode.i_size, GFP_KERNEL);
- if (ret != 0)
- fscache_uncache_page(cifsi->fscache, page);
-}
-
-void __cifs_fscache_readpages_cancel(struct inode *inode, struct list_head
*pages)
-{
- cifs_dbg(FYI, "%s: (fsc: %p, i: %p)\n",
- __func__, CIFS_I(inode)->fscache, inode);
- fscache_readpages_cancel(CIFS_I(inode)->fscache, pages);
-}
-
-void __cifs_fscache_invalidate_page(struct page *page, struct inode *inode)
-{
- struct cifsInodeInfo *cifsi = CIFS_I(inode);
- struct fscache_cookie *cookie = cifsi->fscache;
-
- cifs_dbg(FYI, "%s: (0x%p/0x%p)\n", __func__, page, cookie);
- fscache_wait_on_page_write(cookie, page);
- fscache_uncache_page(cookie, page);
-}
diff --git a/fs/cifs/fscache.h b/fs/cifs/fscache.h
index e811f2dd7619..b86ef0fcf676 100644
--- a/fs/cifs/fscache.h
+++ b/fs/cifs/fscache.h
@@ -21,6 +21,7 @@
#ifndef _CIFS_FSCACHE_H
#define _CIFS_FSCACHE_H
+#define FSCACHE_USE_NEW_IO_API
#include <linux/fscache.h>
#include "cifsglob.h"
@@ -70,56 +71,9 @@ extern void cifs_fscache_release_inode_cookie(struct inode
*);
extern void cifs_fscache_set_inode_cookie(struct inode *, struct file *);
extern void cifs_fscache_reset_inode_cookie(struct inode *);
-extern void __cifs_fscache_invalidate_page(struct page *, struct 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_fscache_readpages_cancel(struct inode *, struct list_head
*);
-
-extern void __cifs_readpage_to_fscache(struct inode *, struct page *);
-
-static inline void cifs_fscache_invalidate_page(struct page *page,
- struct inode *inode)
-{
- if (PageFsCache(page))
- __cifs_fscache_invalidate_page(page, inode);
-}
-
-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);
-}
-
-static inline void cifs_fscache_readpages_cancel(struct inode *inode,
- struct list_head *pages)
+static inline struct fscache_cookie *cifs_inode_cookie(struct inode *inode)
{
- if (CIFS_I(inode)->fscache)
- return __cifs_fscache_readpages_cancel(inode, pages);
+ return CIFS_I(inode)->fscache;
}
#else /* CONFIG_CIFS_FSCACHE */
@@ -138,34 +92,8 @@ static inline void cifs_fscache_release_inode_cookie(struct
inode *inode) {}
static inline void cifs_fscache_set_inode_cookie(struct inode *inode,
struct file *filp) {}
static inline void cifs_fscache_reset_inode_cookie(struct inode *inode) {}
-static inline int cifs_fscache_release_page(struct page *page, gfp_t gfp)
-{
- return 1; /* May release page */
-}
-
-static inline void cifs_fscache_invalidate_page(struct page *page,
- struct inode *inode) {}
-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) {}
-
-static inline void cifs_fscache_readpages_cancel(struct inode *inode,
- struct list_head *pages)
-{
-}
+static inline struct fscache_cookie *cifs_inode_cookie(struct inode *inode) {
return NULL; }
#endif /* CONFIG_CIFS_FSCACHE */
diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index 794fc3b68b4f..788b5a364365 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -36,6 +36,7 @@
#include <linux/uuid.h>
#include <linux/pagemap.h>
#include <linux/xattr.h>
+#include <linux/netfs.h>
#include "smb2pdu.h"
#include "cifsglob.h"
#include "cifsacl.h"
@@ -3984,7 +3985,14 @@ 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);
+ kref_put(&rdata->refcount, cifs_readdata_release);
+ } else {
+ queue_work(cifsiod_wq, &rdata->work);
+ }
DeleteMidQEntry(mid);
add_credits(server, &credits, 0);
}
--
Linux-cachefs mailing list
[email protected]
https://www.redhat.com/mailman/listinfo/linux-cachefs
