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Diffstat (limited to 'fs/nfs/direct.c')
-rw-r--r--fs/nfs/direct.c127
1 files changed, 60 insertions, 67 deletions
diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c
index 9cff8709c80a..1707f46b1335 100644
--- a/fs/nfs/direct.c
+++ b/fs/nfs/direct.c
@@ -59,44 +59,13 @@
#include "internal.h"
#include "iostat.h"
#include "pnfs.h"
+#include "fscache.h"
+#include "nfstrace.h"
#define NFSDBG_FACILITY NFSDBG_VFS
static struct kmem_cache *nfs_direct_cachep;
-struct nfs_direct_req {
- struct kref kref; /* release manager */
-
- /* I/O parameters */
- struct nfs_open_context *ctx; /* file open context info */
- struct nfs_lock_context *l_ctx; /* Lock context info */
- struct kiocb * iocb; /* controlling i/o request */
- struct inode * inode; /* target file of i/o */
-
- /* completion state */
- atomic_t io_count; /* i/os we're waiting for */
- spinlock_t lock; /* protect completion state */
-
- loff_t io_start; /* Start offset for I/O */
- ssize_t count, /* bytes actually processed */
- max_count, /* max expected count */
- bytes_left, /* bytes left to be sent */
- error; /* any reported error */
- struct completion completion; /* wait for i/o completion */
-
- /* commit state */
- struct nfs_mds_commit_info mds_cinfo; /* Storage for cinfo */
- struct pnfs_ds_commit_info ds_cinfo; /* Storage for cinfo */
- struct work_struct work;
- int flags;
- /* for write */
-#define NFS_ODIRECT_DO_COMMIT (1) /* an unstable reply was received */
-#define NFS_ODIRECT_RESCHED_WRITES (2) /* write verification failed */
- /* for read */
-#define NFS_ODIRECT_SHOULD_DIRTY (3) /* dirty user-space page after read */
-#define NFS_ODIRECT_DONE INT_MAX /* write verification failed */
-};
-
static const struct nfs_pgio_completion_ops nfs_direct_write_completion_ops;
static const struct nfs_commit_completion_ops nfs_direct_commit_completion_ops;
static void nfs_direct_write_complete(struct nfs_direct_req *dreq);
@@ -152,28 +121,25 @@ nfs_direct_count_bytes(struct nfs_direct_req *dreq,
}
/**
- * nfs_direct_IO - NFS address space operation for direct I/O
+ * nfs_swap_rw - NFS address space operation for swap I/O
* @iocb: target I/O control block
* @iter: I/O buffer
*
- * The presence of this routine in the address space ops vector means
- * the NFS client supports direct I/O. However, for most direct IO, we
- * shunt off direct read and write requests before the VFS gets them,
- * so this method is only ever called for swap.
+ * Perform IO to the swap-file. This is much like direct IO.
*/
-ssize_t nfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
+int nfs_swap_rw(struct kiocb *iocb, struct iov_iter *iter)
{
- struct inode *inode = iocb->ki_filp->f_mapping->host;
-
- /* we only support swap file calling nfs_direct_IO */
- if (!IS_SWAPFILE(inode))
- return 0;
+ ssize_t ret;
VM_BUG_ON(iov_iter_count(iter) != PAGE_SIZE);
if (iov_iter_rw(iter) == READ)
- return nfs_file_direct_read(iocb, iter);
- return nfs_file_direct_write(iocb, iter);
+ ret = nfs_file_direct_read(iocb, iter, true);
+ else
+ ret = nfs_file_direct_write(iocb, iter, true);
+ if (ret < 0)
+ return ret;
+ return 0;
}
static void nfs_direct_release_pages(struct page **pages, unsigned int npages)
@@ -366,13 +332,12 @@ static ssize_t nfs_direct_read_schedule_iovec(struct nfs_direct_req *dreq,
size_t pgbase;
unsigned npages, i;
- result = iov_iter_get_pages_alloc(iter, &pagevec,
+ result = iov_iter_get_pages_alloc2(iter, &pagevec,
rsize, &pgbase);
if (result < 0)
break;
bytes = result;
- iov_iter_advance(iter, bytes);
npages = (result + pgbase + PAGE_SIZE - 1) / PAGE_SIZE;
for (i = 0; i < npages; i++) {
struct nfs_page *req;
@@ -424,6 +389,7 @@ static ssize_t nfs_direct_read_schedule_iovec(struct nfs_direct_req *dreq,
* nfs_file_direct_read - file direct read operation for NFS files
* @iocb: target I/O control block
* @iter: vector of user buffers into which to read data
+ * @swap: flag indicating this is swap IO, not O_DIRECT IO
*
* We use this function for direct reads instead of calling
* generic_file_aio_read() in order to avoid gfar's check to see if
@@ -439,7 +405,8 @@ static ssize_t nfs_direct_read_schedule_iovec(struct nfs_direct_req *dreq,
* client must read the updated atime from the server back into its
* cache.
*/
-ssize_t nfs_file_direct_read(struct kiocb *iocb, struct iov_iter *iter)
+ssize_t nfs_file_direct_read(struct kiocb *iocb, struct iov_iter *iter,
+ bool swap)
{
struct file *file = iocb->ki_filp;
struct address_space *mapping = file->f_mapping;
@@ -478,15 +445,17 @@ ssize_t nfs_file_direct_read(struct kiocb *iocb, struct iov_iter *iter)
if (!is_sync_kiocb(iocb))
dreq->iocb = iocb;
- if (iter_is_iovec(iter))
+ if (user_backed_iter(iter))
dreq->flags = NFS_ODIRECT_SHOULD_DIRTY;
- nfs_start_io_direct(inode);
+ if (!swap)
+ nfs_start_io_direct(inode);
NFS_I(inode)->read_io += count;
requested = nfs_direct_read_schedule_iovec(dreq, iter, iocb->ki_pos);
- nfs_end_io_direct(inode);
+ if (!swap)
+ nfs_end_io_direct(inode);
if (requested > 0) {
result = nfs_direct_wait(dreq);
@@ -593,14 +562,17 @@ static void nfs_direct_commit_complete(struct nfs_commit_data *data)
struct nfs_page *req;
int status = data->task.tk_status;
+ trace_nfs_direct_commit_complete(dreq);
+
if (status < 0) {
/* Errors in commit are fatal */
dreq->error = status;
dreq->max_count = 0;
dreq->count = 0;
dreq->flags = NFS_ODIRECT_DONE;
- } else if (dreq->flags == NFS_ODIRECT_DONE)
+ } else {
status = dreq->error;
+ }
nfs_init_cinfo_from_dreq(&cinfo, dreq);
@@ -629,6 +601,8 @@ static void nfs_direct_resched_write(struct nfs_commit_info *cinfo,
{
struct nfs_direct_req *dreq = cinfo->dreq;
+ trace_nfs_direct_resched_write(dreq);
+
spin_lock(&dreq->lock);
if (dreq->flags != NFS_ODIRECT_DONE)
dreq->flags = NFS_ODIRECT_RESCHED_WRITES;
@@ -693,6 +667,7 @@ static void nfs_direct_write_schedule_work(struct work_struct *work)
static void nfs_direct_write_complete(struct nfs_direct_req *dreq)
{
+ trace_nfs_direct_write_complete(dreq);
queue_work(nfsiod_workqueue, &dreq->work); /* Calls nfs_direct_write_schedule_work */
}
@@ -703,6 +678,8 @@ static void nfs_direct_write_completion(struct nfs_pgio_header *hdr)
struct nfs_page *req = nfs_list_entry(hdr->pages.next);
int flags = NFS_ODIRECT_DONE;
+ trace_nfs_direct_write_completion(dreq);
+
nfs_init_cinfo_from_dreq(&cinfo, dreq);
spin_lock(&dreq->lock);
@@ -712,7 +689,7 @@ static void nfs_direct_write_completion(struct nfs_pgio_header *hdr)
}
nfs_direct_count_bytes(dreq, hdr);
- if (hdr->good_bytes != 0 && nfs_write_need_commit(hdr)) {
+ if (test_bit(NFS_IOHDR_UNSTABLE_WRITES, &hdr->flags)) {
if (!dreq->flags)
dreq->flags = NFS_ODIRECT_DO_COMMIT;
flags = dreq->flags;
@@ -757,6 +734,8 @@ static void nfs_direct_write_reschedule_io(struct nfs_pgio_header *hdr)
{
struct nfs_direct_req *dreq = hdr->dreq;
+ trace_nfs_direct_write_reschedule_io(dreq);
+
spin_lock(&dreq->lock);
if (dreq->error == 0) {
dreq->flags = NFS_ODIRECT_RESCHED_WRITES;
@@ -789,7 +768,7 @@ static const struct nfs_pgio_completion_ops nfs_direct_write_completion_ops = {
*/
static ssize_t nfs_direct_write_schedule_iovec(struct nfs_direct_req *dreq,
struct iov_iter *iter,
- loff_t pos)
+ loff_t pos, int ioflags)
{
struct nfs_pageio_descriptor desc;
struct inode *inode = dreq->inode;
@@ -797,7 +776,9 @@ static ssize_t nfs_direct_write_schedule_iovec(struct nfs_direct_req *dreq,
size_t requested_bytes = 0;
size_t wsize = max_t(size_t, NFS_SERVER(inode)->wsize, PAGE_SIZE);
- nfs_pageio_init_write(&desc, inode, FLUSH_COND_STABLE, false,
+ trace_nfs_direct_write_schedule_iovec(dreq);
+
+ nfs_pageio_init_write(&desc, inode, ioflags, false,
&nfs_direct_write_completion_ops);
desc.pg_dreq = dreq;
get_dreq(dreq);
@@ -810,13 +791,12 @@ static ssize_t nfs_direct_write_schedule_iovec(struct nfs_direct_req *dreq,
size_t pgbase;
unsigned npages, i;
- result = iov_iter_get_pages_alloc(iter, &pagevec,
+ result = iov_iter_get_pages_alloc2(iter, &pagevec,
wsize, &pgbase);
if (result < 0)
break;
bytes = result;
- iov_iter_advance(iter, bytes);
npages = (result + pgbase + PAGE_SIZE - 1) / PAGE_SIZE;
for (i = 0; i < npages; i++) {
struct nfs_page *req;
@@ -875,6 +855,7 @@ static ssize_t nfs_direct_write_schedule_iovec(struct nfs_direct_req *dreq,
* nfs_file_direct_write - file direct write operation for NFS files
* @iocb: target I/O control block
* @iter: vector of user buffers from which to write data
+ * @swap: flag indicating this is swap IO, not O_DIRECT IO
*
* We use this function for direct writes instead of calling
* generic_file_aio_write() in order to avoid taking the inode
@@ -891,7 +872,8 @@ static ssize_t nfs_direct_write_schedule_iovec(struct nfs_direct_req *dreq,
* Note that O_APPEND is not supported for NFS direct writes, as there
* is no atomic O_APPEND write facility in the NFS protocol.
*/
-ssize_t nfs_file_direct_write(struct kiocb *iocb, struct iov_iter *iter)
+ssize_t nfs_file_direct_write(struct kiocb *iocb, struct iov_iter *iter,
+ bool swap)
{
ssize_t result, requested;
size_t count;
@@ -905,7 +887,11 @@ ssize_t nfs_file_direct_write(struct kiocb *iocb, struct iov_iter *iter)
dfprintk(FILE, "NFS: direct write(%pD2, %zd@%Ld)\n",
file, iov_iter_count(iter), (long long) iocb->ki_pos);
- result = generic_write_checks(iocb, iter);
+ if (swap)
+ /* bypass generic checks */
+ result = iov_iter_count(iter);
+ else
+ result = generic_write_checks(iocb, iter);
if (result <= 0)
return result;
count = result;
@@ -936,16 +922,22 @@ ssize_t nfs_file_direct_write(struct kiocb *iocb, struct iov_iter *iter)
dreq->iocb = iocb;
pnfs_init_ds_commit_info_ops(&dreq->ds_cinfo, inode);
- nfs_start_io_direct(inode);
+ if (swap) {
+ requested = nfs_direct_write_schedule_iovec(dreq, iter, pos,
+ FLUSH_STABLE);
+ } else {
+ nfs_start_io_direct(inode);
- requested = nfs_direct_write_schedule_iovec(dreq, iter, pos);
+ requested = nfs_direct_write_schedule_iovec(dreq, iter, pos,
+ FLUSH_COND_STABLE);
- if (mapping->nrpages) {
- invalidate_inode_pages2_range(mapping,
- pos >> PAGE_SHIFT, end);
- }
+ if (mapping->nrpages) {
+ invalidate_inode_pages2_range(mapping,
+ pos >> PAGE_SHIFT, end);
+ }
- nfs_end_io_direct(inode);
+ nfs_end_io_direct(inode);
+ }
if (requested > 0) {
result = nfs_direct_wait(dreq);
@@ -959,6 +951,7 @@ ssize_t nfs_file_direct_write(struct kiocb *iocb, struct iov_iter *iter)
} else {
result = requested;
}
+ nfs_fscache_invalidate(inode, FSCACHE_INVAL_DIO_WRITE);
out_release:
nfs_direct_req_release(dreq);
out: