[PATCH net-next 1/2] afs: Make afs_fs_fetch_data() take a list of pages
From: David Howells
Date: Fri Jan 06 2017 - 12:09:29 EST
Make afs_fs_fetch_data() take a list of pages for bulk data transfer. This
will allow afs_readpages() to be made more efficient.
Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
---
fs/afs/file.c | 37 ++++++++++++++---
fs/afs/fsclient.c | 117 ++++++++++++++++++++++++++++++++++-------------------
fs/afs/internal.h | 21 +++++++++-
fs/afs/vnode.c | 6 +--
fs/afs/write.c | 19 +++++++--
5 files changed, 145 insertions(+), 55 deletions(-)
diff --git a/fs/afs/file.c b/fs/afs/file.c
index 6344aee4ac4b..6c262ceef32d 100644
--- a/fs/afs/file.c
+++ b/fs/afs/file.c
@@ -101,6 +101,21 @@ int afs_release(struct inode *inode, struct file *file)
return 0;
}
+/*
+ * Dispose of a ref to a read record.
+ */
+void afs_put_read(struct afs_read *req)
+{
+ int i;
+
+ if (atomic_dec_and_test(&req->usage)) {
+ for (i = 0; i < req->nr_pages; i++)
+ if (req->pages[i])
+ put_page(req->pages[i]);
+ kfree(req);
+ }
+}
+
#ifdef CONFIG_AFS_FSCACHE
/*
* deal with notification that a page was read from the cache
@@ -126,9 +141,8 @@ int afs_page_filler(void *data, struct page *page)
{
struct inode *inode = page->mapping->host;
struct afs_vnode *vnode = AFS_FS_I(inode);
+ struct afs_read *req;
struct key *key = data;
- size_t len;
- off_t offset;
int ret;
_enter("{%x},{%lu},{%lu}", key_serial(key), inode->i_ino, page->index);
@@ -164,12 +178,23 @@ int afs_page_filler(void *data, struct page *page)
_debug("cache said ENOBUFS");
default:
go_on:
- offset = page->index << PAGE_SHIFT;
- len = min_t(size_t, i_size_read(inode) - offset, PAGE_SIZE);
+ req = kzalloc(sizeof(struct afs_read) + sizeof(struct page *),
+ GFP_KERNEL);
+ if (!req)
+ goto enomem;
+
+ atomic_set(&req->usage, 1);
+ req->pos = (loff_t)page->index << PAGE_SHIFT;
+ req->len = min_t(size_t, i_size_read(inode) - req->pos,
+ PAGE_SIZE);
+ req->nr_pages = 1;
+ req->pages[0] = page;
+ get_page(page);
/* read the contents of the file from the server into the
* page */
- ret = afs_vnode_fetch_data(vnode, key, offset, len, page);
+ ret = afs_vnode_fetch_data(vnode, key, req);
+ afs_put_read(req);
if (ret < 0) {
if (ret == -ENOENT) {
_debug("got NOENT from server"
@@ -201,6 +226,8 @@ int afs_page_filler(void *data, struct page *page)
_leave(" = 0");
return 0;
+enomem:
+ ret = -ENOMEM;
error:
SetPageError(page);
unlock_page(page);
diff --git a/fs/afs/fsclient.c b/fs/afs/fsclient.c
index 31c616ab9b40..7dc1f6fb3661 100644
--- a/fs/afs/fsclient.c
+++ b/fs/afs/fsclient.c
@@ -309,15 +309,19 @@ int afs_fs_fetch_file_status(struct afs_server *server,
static int afs_deliver_fs_fetch_data(struct afs_call *call)
{
struct afs_vnode *vnode = call->reply;
+ struct afs_read *req = call->reply3;
const __be32 *bp;
- struct page *page;
+ unsigned int size;
void *buffer;
int ret;
- _enter("{%u}", call->unmarshall);
+ _enter("{%u,%zu/%u;%u/%llu}",
+ call->unmarshall, call->offset, call->count,
+ req->remain, req->actual_len);
switch (call->unmarshall) {
case 0:
+ req->actual_len = 0;
call->offset = 0;
call->unmarshall++;
if (call->operation_ID != FSFETCHDATA64) {
@@ -334,10 +338,8 @@ static int afs_deliver_fs_fetch_data(struct afs_call *call)
if (ret < 0)
return ret;
- call->count = ntohl(call->tmp);
- _debug("DATA length MSW: %u", call->count);
- if (call->count > 0)
- return -EBADMSG;
+ req->actual_len = ntohl(call->tmp);
+ req->actual_len <<= 32;
call->offset = 0;
call->unmarshall++;
@@ -349,26 +351,52 @@ static int afs_deliver_fs_fetch_data(struct afs_call *call)
if (ret < 0)
return ret;
- call->count = ntohl(call->tmp);
- _debug("DATA length: %u", call->count);
- if (call->count > PAGE_SIZE)
+ req->actual_len |= ntohl(call->tmp);
+ _debug("DATA length: %llu", req->actual_len);
+ /* Check that the server didn't want to send us extra. We
+ * might want to just discard instead, but that requires
+ * cooperation from AF_RXRPC.
+ */
+ if (req->actual_len > req->len)
return -EBADMSG;
- call->offset = 0;
+
+ req->remain = req->actual_len;
+ call->offset = req->pos & (PAGE_SIZE - 1);
+ req->index = 0;
+ if (req->actual_len == 0)
+ goto no_more_data;
call->unmarshall++;
+ begin_page:
+ if (req->remain > PAGE_SIZE - call->offset)
+ size = PAGE_SIZE - call->offset;
+ else
+ size = req->remain;
+ call->count = call->offset + size;
+ ASSERTCMP(call->count, <=, PAGE_SIZE);
+ req->remain -= size;
+
/* extract the returned data */
case 3:
- _debug("extract data");
- if (call->count > 0) {
- page = call->reply3;
- buffer = kmap(page);
- ret = afs_extract_data(call, buffer,
- call->count, true);
- kunmap(page);
- if (ret < 0)
- return ret;
+ _debug("extract data %u/%llu %zu/%u",
+ req->remain, req->actual_len, call->offset, call->count);
+
+ buffer = kmap(req->pages[req->index]);
+ ret = afs_extract_data(call, buffer, call->count, true);
+ kunmap(req->pages[req->index]);
+ if (ret < 0)
+ return ret;
+ if (call->offset == PAGE_SIZE) {
+ if (req->page_done)
+ req->page_done(call, req);
+ if (req->remain > 0) {
+ req->index++;
+ call->offset = 0;
+ goto begin_page;
+ }
}
+ no_more_data:
call->offset = 0;
call->unmarshall++;
@@ -393,17 +421,25 @@ static int afs_deliver_fs_fetch_data(struct afs_call *call)
}
if (call->count < PAGE_SIZE) {
- _debug("clear");
- page = call->reply3;
- buffer = kmap(page);
+ buffer = kmap(req->pages[req->index]);
memset(buffer + call->count, 0, PAGE_SIZE - call->count);
- kunmap(page);
+ kunmap(req->pages[req->index]);
+ if (req->page_done)
+ req->page_done(call, req);
}
_leave(" = 0 [done]");
return 0;
}
+static void afs_fetch_data_destructor(struct afs_call *call)
+{
+ struct afs_read *req = call->reply3;
+
+ afs_put_read(req);
+ afs_flat_call_destructor(call);
+}
+
/*
* FS.FetchData operation type
*/
@@ -411,14 +447,14 @@ static const struct afs_call_type afs_RXFSFetchData = {
.name = "FS.FetchData",
.deliver = afs_deliver_fs_fetch_data,
.abort_to_error = afs_abort_to_error,
- .destructor = afs_flat_call_destructor,
+ .destructor = afs_fetch_data_destructor,
};
static const struct afs_call_type afs_RXFSFetchData64 = {
.name = "FS.FetchData64",
.deliver = afs_deliver_fs_fetch_data,
.abort_to_error = afs_abort_to_error,
- .destructor = afs_flat_call_destructor,
+ .destructor = afs_fetch_data_destructor,
};
/*
@@ -427,8 +463,7 @@ static const struct afs_call_type afs_RXFSFetchData64 = {
static int afs_fs_fetch_data64(struct afs_server *server,
struct key *key,
struct afs_vnode *vnode,
- off_t offset, size_t length,
- struct page *buffer,
+ struct afs_read *req,
const struct afs_wait_mode *wait_mode)
{
struct afs_call *call;
@@ -436,8 +471,6 @@ static int afs_fs_fetch_data64(struct afs_server *server,
_enter("");
- ASSERTCMP(length, <, ULONG_MAX);
-
call = afs_alloc_flat_call(&afs_RXFSFetchData64, 32, (21 + 3 + 6) * 4);
if (!call)
return -ENOMEM;
@@ -445,7 +478,7 @@ static int afs_fs_fetch_data64(struct afs_server *server,
call->key = key;
call->reply = vnode;
call->reply2 = NULL; /* volsync */
- call->reply3 = buffer;
+ call->reply3 = req;
call->service_id = FS_SERVICE;
call->port = htons(AFS_FS_PORT);
call->operation_ID = FSFETCHDATA64;
@@ -456,11 +489,12 @@ static int afs_fs_fetch_data64(struct afs_server *server,
bp[1] = htonl(vnode->fid.vid);
bp[2] = htonl(vnode->fid.vnode);
bp[3] = htonl(vnode->fid.unique);
- bp[4] = htonl(upper_32_bits(offset));
- bp[5] = htonl((u32) offset);
+ bp[4] = htonl(upper_32_bits(req->pos));
+ bp[5] = htonl(lower_32_bits(req->pos));
bp[6] = 0;
- bp[7] = htonl((u32) length);
+ bp[7] = htonl(lower_32_bits(req->len));
+ atomic_inc(&req->usage);
return afs_make_call(&server->addr, call, GFP_NOFS, wait_mode);
}
@@ -470,16 +504,16 @@ static int afs_fs_fetch_data64(struct afs_server *server,
int afs_fs_fetch_data(struct afs_server *server,
struct key *key,
struct afs_vnode *vnode,
- off_t offset, size_t length,
- struct page *buffer,
+ struct afs_read *req,
const struct afs_wait_mode *wait_mode)
{
struct afs_call *call;
__be32 *bp;
- if (upper_32_bits(offset) || upper_32_bits(offset + length))
- return afs_fs_fetch_data64(server, key, vnode, offset, length,
- buffer, wait_mode);
+ if (upper_32_bits(req->pos) ||
+ upper_32_bits(req->len) ||
+ upper_32_bits(req->pos + req->len))
+ return afs_fs_fetch_data64(server, key, vnode, req, wait_mode);
_enter("");
@@ -490,7 +524,7 @@ int afs_fs_fetch_data(struct afs_server *server,
call->key = key;
call->reply = vnode;
call->reply2 = NULL; /* volsync */
- call->reply3 = buffer;
+ call->reply3 = req;
call->service_id = FS_SERVICE;
call->port = htons(AFS_FS_PORT);
call->operation_ID = FSFETCHDATA;
@@ -501,9 +535,10 @@ int afs_fs_fetch_data(struct afs_server *server,
bp[1] = htonl(vnode->fid.vid);
bp[2] = htonl(vnode->fid.vnode);
bp[3] = htonl(vnode->fid.unique);
- bp[4] = htonl(offset);
- bp[5] = htonl(length);
+ bp[4] = htonl(lower_32_bits(req->pos));
+ bp[5] = htonl(lower_32_bits(req->len));
+ atomic_inc(&req->usage);
return afs_make_call(&server->addr, call, GFP_NOFS, wait_mode);
}
diff --git a/fs/afs/internal.h b/fs/afs/internal.h
index 535a38d2c1d0..6f7a9638ba1a 100644
--- a/fs/afs/internal.h
+++ b/fs/afs/internal.h
@@ -134,6 +134,22 @@ struct afs_call_type {
};
/*
+ * Record of an outstanding read operation on a vnode.
+ */
+struct afs_read {
+ loff_t pos; /* Where to start reading */
+ loff_t len; /* How much to read */
+ loff_t actual_len; /* How much we're actually getting */
+ atomic_t usage;
+ unsigned int remain; /* Amount remaining */
+ unsigned int index; /* Which page we're reading into */
+ unsigned int pg_offset; /* Offset in page we're at */
+ unsigned int nr_pages;
+ void (*page_done)(struct afs_call *, struct afs_read *);
+ struct page *pages[];
+};
+
+/*
* record of an outstanding writeback on a vnode
*/
struct afs_writeback {
@@ -494,6 +510,7 @@ extern const struct file_operations afs_file_operations;
extern int afs_open(struct inode *, struct file *);
extern int afs_release(struct inode *, struct file *);
extern int afs_page_filler(void *, struct page *);
+extern void afs_put_read(struct afs_read *);
/*
* flock.c
@@ -513,7 +530,7 @@ extern int afs_fs_fetch_file_status(struct afs_server *, struct key *,
extern int afs_fs_give_up_callbacks(struct afs_server *,
const struct afs_wait_mode *);
extern int afs_fs_fetch_data(struct afs_server *, struct key *,
- struct afs_vnode *, off_t, size_t, struct page *,
+ struct afs_vnode *, struct afs_read *,
const struct afs_wait_mode *);
extern int afs_fs_create(struct afs_server *, struct key *,
struct afs_vnode *, const char *, umode_t,
@@ -699,7 +716,7 @@ extern void afs_vnode_finalise_status_update(struct afs_vnode *,
extern int afs_vnode_fetch_status(struct afs_vnode *, struct afs_vnode *,
struct key *);
extern int afs_vnode_fetch_data(struct afs_vnode *, struct key *,
- off_t, size_t, struct page *);
+ struct afs_read *);
extern int afs_vnode_create(struct afs_vnode *, struct key *, const char *,
umode_t, struct afs_fid *, struct afs_file_status *,
struct afs_callback *, struct afs_server **);
diff --git a/fs/afs/vnode.c b/fs/afs/vnode.c
index 25cf4c3f4ff7..45aa874f5d32 100644
--- a/fs/afs/vnode.c
+++ b/fs/afs/vnode.c
@@ -393,7 +393,7 @@ int afs_vnode_fetch_status(struct afs_vnode *vnode,
* - TODO implement caching
*/
int afs_vnode_fetch_data(struct afs_vnode *vnode, struct key *key,
- off_t offset, size_t length, struct page *page)
+ struct afs_read *desc)
{
struct afs_server *server;
int ret;
@@ -420,8 +420,8 @@ int afs_vnode_fetch_data(struct afs_vnode *vnode, struct key *key,
_debug("USING SERVER: %08x\n", ntohl(server->addr.s_addr));
- ret = afs_fs_fetch_data(server, key, vnode, offset, length,
- page, &afs_sync_call);
+ ret = afs_fs_fetch_data(server, key, vnode, desc,
+ &afs_sync_call);
} while (!afs_volume_release_fileserver(vnode, server, ret));
diff --git a/fs/afs/write.c b/fs/afs/write.c
index f865c3f05bea..c83c1a0e851f 100644
--- a/fs/afs/write.c
+++ b/fs/afs/write.c
@@ -86,19 +86,30 @@ void afs_put_writeback(struct afs_writeback *wb)
static int afs_fill_page(struct afs_vnode *vnode, struct key *key,
loff_t pos, struct page *page)
{
+ struct afs_read *req;
loff_t i_size;
int ret;
- int len;
_enter(",,%llu", (unsigned long long)pos);
+ req = kzalloc(sizeof(struct afs_read) + sizeof(struct page *),
+ GFP_KERNEL);
+ if (!req)
+ return -ENOMEM;
+
+ atomic_set(&req->usage, 1);
+ req->pos = pos;
+ req->nr_pages = 1;
+ req->pages[0] = page;
+
i_size = i_size_read(&vnode->vfs_inode);
if (pos + PAGE_SIZE > i_size)
- len = i_size - pos;
+ req->len = i_size - pos;
else
- len = PAGE_SIZE;
+ req->len = PAGE_SIZE;
- ret = afs_vnode_fetch_data(vnode, key, pos, len, page);
+ ret = afs_vnode_fetch_data(vnode, key, req);
+ afs_put_read(req);
if (ret < 0) {
if (ret == -ENOENT) {
_debug("got NOENT from server"