[PATCH v6 02/15] cifs: Replace cifs_writedata with a wrapper around netfs_io_subrequest

From: David Howells
Date: Thu Mar 28 2024 - 12:59:58 EST

Replace the cifs_writedata struct with the same wrapper around
netfs_io_subrequest that was used to replace cifs_readdata.

Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
cc: Steve French <sfrench@xxxxxxxxx>
cc: Shyam Prasad N <nspmangalore@xxxxxxxxx>
cc: Rohith Surabattula <rohiths.msft@xxxxxxxxx>
cc: Jeff Layton <jlayton@xxxxxxxxxx>
cc: linux-cifs@xxxxxxxxxxxxxxx
cc: netfs@xxxxxxxxxxxxxxx
cc: linux-fsdevel@xxxxxxxxxxxxxxx
cc: linux-mm@xxxxxxxxx
---
fs/smb/client/cifsglob.h | 32 +++-------------
fs/smb/client/cifsproto.h | 16 ++++++--
fs/smb/client/cifssmb.c | 9 ++---
fs/smb/client/file.c | 79 ++++++++++++++++-----------------------
fs/smb/client/smb2pdu.c | 9 ++---
fs/smb/client/smb2proto.h | 3 +-
6 files changed, 59 insertions(+), 89 deletions(-)

diff --git a/fs/smb/client/cifsglob.h b/fs/smb/client/cifsglob.h
index 930b2879383a..99c235bac554 100644
--- a/fs/smb/client/cifsglob.h
+++ b/fs/smb/client/cifsglob.h
@@ -269,7 +269,6 @@ struct cifs_fattr;
struct smb3_fs_context;
struct cifs_fid;
struct cifs_io_subrequest;
-struct cifs_writedata;
struct cifs_io_parms;
struct cifs_search_info;
struct cifsInodeInfo;
@@ -452,8 +451,7 @@ struct smb_version_operations {
/* async read from the server */
int (*async_readv)(struct cifs_io_subrequest *);
/* async write to the server */
- int (*async_writev)(struct cifs_writedata *,
- void (*release)(struct kref *));
+ int (*async_writev)(struct cifs_io_subrequest *);
/* sync read from the server */
int (*sync_read)(const unsigned int, struct cifs_fid *,
struct cifs_io_parms *, unsigned int *, char **,
@@ -1503,36 +1501,18 @@ struct cifs_io_subrequest {
#endif
struct cifs_credits credits;

- // TODO: Remove following elements
- struct list_head list;
- struct completion done;
- struct work_struct work;
- struct iov_iter iter;
- __u64 offset;
- unsigned int bytes;
-};
+ enum writeback_sync_modes sync_mode;
+ bool uncached;
+ bool replay;
+ struct bio_vec *bv;

-/* asynchronous write support */
-struct cifs_writedata {
- struct kref refcount;
+ // TODO: Remove following elements
struct list_head list;
struct completion done;
- enum writeback_sync_modes sync_mode;
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;
- int result;
- struct TCP_Server_Info *server;
-#ifdef CONFIG_CIFS_SMB_DIRECT
- struct smbd_mr *mr;
-#endif
- struct cifs_credits credits;
- bool replay;
};

/*
diff --git a/fs/smb/client/cifsproto.h b/fs/smb/client/cifsproto.h
index ccb6999dd26f..010601a89fe5 100644
--- a/fs/smb/client/cifsproto.h
+++ b/fs/smb/client/cifsproto.h
@@ -611,11 +611,19 @@ static inline void cifs_put_readdata(struct cifs_io_subrequest *rdata)
int cifs_async_readv(struct cifs_io_subrequest *rdata);
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));
+int cifs_async_writev(struct cifs_io_subrequest *wdata);
void cifs_writev_complete(struct work_struct *work);
-struct cifs_writedata *cifs_writedata_alloc(work_func_t complete);
-void cifs_writedata_release(struct kref *refcount);
+struct cifs_io_subrequest *cifs_writedata_alloc(work_func_t complete);
+void cifs_writedata_release(struct cifs_io_subrequest *rdata);
+static inline void cifs_get_writedata(struct cifs_io_subrequest *wdata)
+{
+ refcount_inc(&wdata->subreq.ref);
+}
+static inline void cifs_put_writedata(struct cifs_io_subrequest *wdata)
+{
+ if (refcount_dec_and_test(&wdata->subreq.ref))
+ cifs_writedata_release(wdata);
+}
int cifs_query_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
struct cifs_sb_info *cifs_sb,
const unsigned char *path, char *pbuf,
diff --git a/fs/smb/client/cifssmb.c b/fs/smb/client/cifssmb.c
index 014171cc5cf7..c84f2991c93a 100644
--- a/fs/smb/client/cifssmb.c
+++ b/fs/smb/client/cifssmb.c
@@ -1612,7 +1612,7 @@ CIFSSMBWrite(const unsigned int xid, struct cifs_io_parms *io_parms,
static void
cifs_writev_callback(struct mid_q_entry *mid)
{
- struct cifs_writedata *wdata = mid->callback_data;
+ struct cifs_io_subrequest *wdata = mid->callback_data;
struct cifs_tcon *tcon = tlink_tcon(wdata->cfile->tlink);
unsigned int written;
WRITE_RSP *smb = (WRITE_RSP *)mid->resp_buf;
@@ -1657,8 +1657,7 @@ cifs_writev_callback(struct mid_q_entry *mid)

/* cifs_async_writev - send an async write, and set up mid to handle result */
int
-cifs_async_writev(struct cifs_writedata *wdata,
- void (*release)(struct kref *kref))
+cifs_async_writev(struct cifs_io_subrequest *wdata)
{
int rc = -EACCES;
WRITE_REQ *smb = NULL;
@@ -1725,14 +1724,14 @@ cifs_async_writev(struct cifs_writedata *wdata,
iov[1].iov_len += 4; /* pad bigger by four bytes */
}

- kref_get(&wdata->refcount);
+ cifs_get_writedata(wdata);
rc = cifs_call_async(tcon->ses->server, &rqst, NULL,
cifs_writev_callback, NULL, wdata, 0, NULL);

if (rc == 0)
cifs_stats_inc(&tcon->stats.cifs_stats.num_writes);
else
- kref_put(&wdata->refcount, release);
+ cifs_put_writedata(wdata);

async_writev_out:
cifs_small_buf_release(smb);
diff --git a/fs/smb/client/file.c b/fs/smb/client/file.c
index d70d3c12bb70..32c36947c515 100644
--- a/fs/smb/client/file.c
+++ b/fs/smb/client/file.c
@@ -2431,10 +2431,10 @@ cifs_get_readable_path(struct cifs_tcon *tcon, const char *name,
}

void
-cifs_writedata_release(struct kref *refcount)
+cifs_writedata_release(struct cifs_io_subrequest *wdata)
{
- struct cifs_writedata *wdata = container_of(refcount,
- struct cifs_writedata, refcount);
+ if (wdata->uncached)
+ kref_put(&wdata->ctx->refcount, cifs_aio_ctx_release);
#ifdef CONFIG_CIFS_SMB_DIRECT
if (wdata->mr) {
smbd_deregister_mr(wdata->mr);
@@ -2453,7 +2453,7 @@ cifs_writedata_release(struct kref *refcount)
* possible that the page was redirtied so re-clean the page.
*/
static void
-cifs_writev_requeue(struct cifs_writedata *wdata)
+cifs_writev_requeue(struct cifs_io_subrequest *wdata)
{
int rc = 0;
struct inode *inode = d_inode(wdata->cfile->dentry);
@@ -2463,7 +2463,7 @@ cifs_writev_requeue(struct cifs_writedata *wdata)

server = tlink_tcon(wdata->cfile->tlink)->ses->server;
do {
- struct cifs_writedata *wdata2;
+ struct cifs_io_subrequest *wdata2;
unsigned int wsize, cur_len;

wsize = server->ops->wp_retry_size(inode);
@@ -2486,7 +2486,7 @@ cifs_writev_requeue(struct cifs_writedata *wdata)
wdata2->sync_mode = wdata->sync_mode;
wdata2->offset = fpos;
wdata2->bytes = cur_len;
- wdata2->iter = wdata->iter;
+ wdata2->iter = wdata->iter;

iov_iter_advance(&wdata2->iter, fpos - wdata->offset);
iov_iter_truncate(&wdata2->iter, wdata2->bytes);
@@ -2508,11 +2508,10 @@ cifs_writev_requeue(struct cifs_writedata *wdata)
rc = -EBADF;
} else {
wdata2->pid = wdata2->cfile->pid;
- rc = server->ops->async_writev(wdata2,
- cifs_writedata_release);
+ rc = server->ops->async_writev(wdata2);
}

- kref_put(&wdata2->refcount, cifs_writedata_release);
+ cifs_put_writedata(wdata2);
if (rc) {
if (is_retryable_error(rc))
continue;
@@ -2531,14 +2530,14 @@ cifs_writev_requeue(struct cifs_writedata *wdata)

if (rc != 0 && !is_retryable_error(rc))
mapping_set_error(inode->i_mapping, rc);
- kref_put(&wdata->refcount, cifs_writedata_release);
+ cifs_put_writedata(wdata);
}

void
cifs_writev_complete(struct work_struct *work)
{
- struct cifs_writedata *wdata = container_of(work,
- struct cifs_writedata, work);
+ struct cifs_io_subrequest *wdata = container_of(work,
+ struct cifs_io_subrequest, work);
struct inode *inode = d_inode(wdata->cfile->dentry);

if (wdata->result == 0) {
@@ -2559,16 +2558,16 @@ cifs_writev_complete(struct work_struct *work)

if (wdata->result != -EAGAIN)
mapping_set_error(inode->i_mapping, wdata->result);
- kref_put(&wdata->refcount, cifs_writedata_release);
+ cifs_put_writedata(wdata);
}

-struct cifs_writedata *cifs_writedata_alloc(work_func_t complete)
+struct cifs_io_subrequest *cifs_writedata_alloc(work_func_t complete)
{
- struct cifs_writedata *wdata;
+ struct cifs_io_subrequest *wdata;

wdata = kzalloc(sizeof(*wdata), GFP_NOFS);
if (wdata != NULL) {
- kref_init(&wdata->refcount);
+ refcount_set(&wdata->subreq.ref, 1);
INIT_LIST_HEAD(&wdata->list);
init_completion(&wdata->done);
INIT_WORK(&wdata->work, complete);
@@ -2699,7 +2698,7 @@ static ssize_t cifs_write_back_from_locked_folio(struct address_space *mapping,
{
struct inode *inode = mapping->host;
struct TCP_Server_Info *server;
- struct cifs_writedata *wdata;
+ struct cifs_io_subrequest *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;
@@ -2792,10 +2791,9 @@ static ssize_t cifs_write_back_from_locked_folio(struct address_space *mapping,
if (wdata->cfile->invalidHandle)
rc = -EAGAIN;
else
- rc = wdata->server->ops->async_writev(wdata,
- cifs_writedata_release);
+ rc = wdata->server->ops->async_writev(wdata);
if (rc >= 0) {
- kref_put(&wdata->refcount, cifs_writedata_release);
+ cifs_put_writedata(wdata);
goto err_close;
}
} else {
@@ -2805,7 +2803,7 @@ static ssize_t cifs_write_back_from_locked_folio(struct address_space *mapping,
}

err_wdata:
- kref_put(&wdata->refcount, cifs_writedata_release);
+ cifs_put_writedata(wdata);
err_uncredit:
add_credits_and_wake_if(server, credits, 0);
err_close:
@@ -3182,23 +3180,13 @@ int cifs_flush(struct file *file, fl_owner_t id)
return rc;
}

-static void
-cifs_uncached_writedata_release(struct kref *refcount)
-{
- struct cifs_writedata *wdata = container_of(refcount,
- struct cifs_writedata, refcount);
-
- kref_put(&wdata->ctx->refcount, cifs_aio_ctx_release);
- cifs_writedata_release(refcount);
-}
-
static void collect_uncached_write_data(struct cifs_aio_ctx *ctx);

static void
cifs_uncached_writev_complete(struct work_struct *work)
{
- struct cifs_writedata *wdata = container_of(work,
- struct cifs_writedata, work);
+ struct cifs_io_subrequest *wdata = container_of(work,
+ struct cifs_io_subrequest, work);
struct inode *inode = d_inode(wdata->cfile->dentry);
struct cifsInodeInfo *cifsi = CIFS_I(inode);

@@ -3211,11 +3199,11 @@ cifs_uncached_writev_complete(struct work_struct *work)
complete(&wdata->done);
collect_uncached_write_data(wdata->ctx);
/* the below call can possibly free the last ref to aio ctx */
- kref_put(&wdata->refcount, cifs_uncached_writedata_release);
+ cifs_put_writedata(wdata);
}

static int
-cifs_resend_wdata(struct cifs_writedata *wdata, struct list_head *wdata_list,
+cifs_resend_wdata(struct cifs_io_subrequest *wdata, struct list_head *wdata_list,
struct cifs_aio_ctx *ctx)
{
unsigned int wsize;
@@ -3265,8 +3253,7 @@ cifs_resend_wdata(struct cifs_writedata *wdata, struct list_head *wdata_list,
wdata->mr = NULL;
}
#endif
- rc = server->ops->async_writev(wdata,
- cifs_uncached_writedata_release);
+ rc = server->ops->async_writev(wdata);
}
}

@@ -3281,7 +3268,7 @@ cifs_resend_wdata(struct cifs_writedata *wdata, struct list_head *wdata_list,
} while (rc == -EAGAIN);

fail:
- kref_put(&wdata->refcount, cifs_uncached_writedata_release);
+ cifs_put_writedata(wdata);
return rc;
}

@@ -3333,7 +3320,7 @@ cifs_write_from_iter(loff_t fpos, size_t len, struct iov_iter *from,
{
int rc = 0;
size_t cur_len, max_len;
- struct cifs_writedata *wdata;
+ struct cifs_io_subrequest *wdata;
pid_t pid;
struct TCP_Server_Info *server;
unsigned int xid, max_segs = INT_MAX;
@@ -3397,6 +3384,7 @@ cifs_write_from_iter(loff_t fpos, size_t len, struct iov_iter *from,
break;
}

+ wdata->uncached = true;
wdata->sync_mode = WB_SYNC_ALL;
wdata->offset = (__u64)fpos;
wdata->cfile = cifsFileInfo_get(open_file);
@@ -3416,14 +3404,12 @@ cifs_write_from_iter(loff_t fpos, size_t len, struct iov_iter *from,
if (wdata->cfile->invalidHandle)
rc = -EAGAIN;
else
- rc = server->ops->async_writev(wdata,
- cifs_uncached_writedata_release);
+ rc = server->ops->async_writev(wdata);
}

if (rc) {
add_credits_and_wake_if(server, &wdata->credits, 0);
- kref_put(&wdata->refcount,
- cifs_uncached_writedata_release);
+ cifs_put_writedata(wdata);
if (rc == -EAGAIN)
continue;
break;
@@ -3441,7 +3427,7 @@ cifs_write_from_iter(loff_t fpos, size_t len, struct iov_iter *from,

static void collect_uncached_write_data(struct cifs_aio_ctx *ctx)
{
- struct cifs_writedata *wdata, *tmp;
+ struct cifs_io_subrequest *wdata, *tmp;
struct cifs_tcon *tcon;
struct cifs_sb_info *cifs_sb;
struct dentry *dentry = ctx->cfile->dentry;
@@ -3496,8 +3482,7 @@ static void collect_uncached_write_data(struct cifs_aio_ctx *ctx)
ctx->cfile, cifs_sb, &tmp_list,
ctx);

- kref_put(&wdata->refcount,
- cifs_uncached_writedata_release);
+ cifs_put_writedata(wdata);
}

list_splice(&tmp_list, &ctx->list);
@@ -3505,7 +3490,7 @@ static void collect_uncached_write_data(struct cifs_aio_ctx *ctx)
}
}
list_del_init(&wdata->list);
- kref_put(&wdata->refcount, cifs_uncached_writedata_release);
+ cifs_put_writedata(wdata);
}

cifs_stats_bytes_written(tcon, ctx->total_len);
diff --git a/fs/smb/client/smb2pdu.c b/fs/smb/client/smb2pdu.c
index 33a7ad4f16bb..f2f7e107fab4 100644
--- a/fs/smb/client/smb2pdu.c
+++ b/fs/smb/client/smb2pdu.c
@@ -4724,7 +4724,7 @@ SMB2_read(const unsigned int xid, struct cifs_io_parms *io_parms,
static void
smb2_writev_callback(struct mid_q_entry *mid)
{
- struct cifs_writedata *wdata = mid->callback_data;
+ struct cifs_io_subrequest *wdata = mid->callback_data;
struct cifs_tcon *tcon = tlink_tcon(wdata->cfile->tlink);
struct TCP_Server_Info *server = wdata->server;
unsigned int written;
@@ -4805,8 +4805,7 @@ smb2_writev_callback(struct mid_q_entry *mid)

/* smb2_async_writev - send an async write, and set up mid to handle result */
int
-smb2_async_writev(struct cifs_writedata *wdata,
- void (*release)(struct kref *kref))
+smb2_async_writev(struct cifs_io_subrequest *wdata)
{
int rc = -EACCES, flags = 0;
struct smb2_write_req *req = NULL;
@@ -4940,7 +4939,7 @@ smb2_async_writev(struct cifs_writedata *wdata,
flags |= CIFS_HAS_CREDITS;
}

- kref_get(&wdata->refcount);
+ cifs_get_writedata(wdata);
rc = cifs_call_async(server, &rqst, NULL, smb2_writev_callback, NULL,
wdata, flags, &wdata->credits);

@@ -4952,7 +4951,7 @@ smb2_async_writev(struct cifs_writedata *wdata,
io_parms->offset,
io_parms->length,
rc);
- kref_put(&wdata->refcount, release);
+ cifs_put_writedata(wdata);
cifs_stats_fail_inc(tcon, SMB2_WRITE_HE);
}

diff --git a/fs/smb/client/smb2proto.h b/fs/smb/client/smb2proto.h
index 740053c0118e..c781eaa0cba8 100644
--- a/fs/smb/client/smb2proto.h
+++ b/fs/smb/client/smb2proto.h
@@ -213,8 +213,7 @@ extern int SMB2_get_srv_num(const unsigned int xid, struct cifs_tcon *tcon,
extern int smb2_async_readv(struct cifs_io_subrequest *rdata);
extern int SMB2_read(const unsigned int xid, struct cifs_io_parms *io_parms,
unsigned int *nbytes, char **buf, int *buf_type);
-extern int smb2_async_writev(struct cifs_writedata *wdata,
- void (*release)(struct kref *kref));
+extern int smb2_async_writev(struct cifs_io_subrequest *wdata);
extern int SMB2_write(const unsigned int xid, struct cifs_io_parms *io_parms,
unsigned int *nbytes, struct kvec *iov, int n_vec);
extern int SMB2_echo(struct TCP_Server_Info *server);