fuse: make request allocations for background processing explicit
There are two types of processing requests in FUSE: synchronous (via
fuse_request_send()) and asynchronous (via adding to fc->bg_queue).
Fortunately, the type of processing is always known in advance, at the time
of request allocation. This preparatory patch utilizes this fact making
fuse_get_req() aware about the type. Next patches will use it.
Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
diff --git a/fs/fuse/cuse.c b/fs/fuse/cuse.c
index 6f96a8d..b7c7f30 100644
--- a/fs/fuse/cuse.c
+++ b/fs/fuse/cuse.c
@@ -422,7 +422,7 @@
BUILD_BUG_ON(CUSE_INIT_INFO_MAX > PAGE_SIZE);
- req = fuse_get_req(fc, 1);
+ req = fuse_get_req_for_background(fc, 1);
if (IS_ERR(req)) {
rc = PTR_ERR(req);
goto err;
diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
index 11dfa0c..3b8301f 100644
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -130,7 +130,8 @@
req->in.h.pid = current->pid;
}
-struct fuse_req *fuse_get_req(struct fuse_conn *fc, unsigned npages)
+static struct fuse_req *__fuse_get_req(struct fuse_conn *fc, unsigned npages,
+ bool for_background)
{
struct fuse_req *req;
sigset_t oldset;
@@ -156,14 +157,27 @@
fuse_req_init_context(req);
req->waiting = 1;
+ req->background = for_background;
return req;
out:
atomic_dec(&fc->num_waiting);
return ERR_PTR(err);
}
+
+struct fuse_req *fuse_get_req(struct fuse_conn *fc, unsigned npages)
+{
+ return __fuse_get_req(fc, npages, false);
+}
EXPORT_SYMBOL_GPL(fuse_get_req);
+struct fuse_req *fuse_get_req_for_background(struct fuse_conn *fc,
+ unsigned npages)
+{
+ return __fuse_get_req(fc, npages, true);
+}
+EXPORT_SYMBOL_GPL(fuse_get_req_for_background);
+
/*
* Return request in fuse_file->reserved_req. However that may
* currently be in use. If that is the case, wait for it to become
@@ -232,6 +246,7 @@
fuse_req_init_context(req);
req->waiting = 1;
+ req->background = 0;
return req;
}
@@ -442,6 +457,7 @@
static void __fuse_request_send(struct fuse_conn *fc, struct fuse_req *req)
{
+ BUG_ON(req->background);
spin_lock(&fc->lock);
if (!fc->connected)
req->out.h.error = -ENOTCONN;
@@ -469,7 +485,7 @@
static void fuse_request_send_nowait_locked(struct fuse_conn *fc,
struct fuse_req *req)
{
- req->background = 1;
+ BUG_ON(!req->background);
fc->num_background++;
if (fc->num_background == fc->max_background)
fc->blocked = 1;
diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index 34b80ba..4884790 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -126,11 +126,13 @@
struct fuse_req *req = ff->reserved_req;
if (sync) {
+ req->background = 0;
fuse_request_send(ff->fc, req);
path_put(&req->misc.release.path);
fuse_put_request(ff->fc, req);
} else {
req->end = fuse_release_end;
+ req->background = 1;
fuse_request_send_background(ff->fc, req);
}
kfree(ff);
@@ -282,6 +284,7 @@
WARN_ON(atomic_read(&ff->count) > 1);
fuse_prepare_release(ff, flags, FUSE_RELEASE);
ff->reserved_req->force = 1;
+ ff->reserved_req->background = 0;
fuse_request_send(ff->fc, ff->reserved_req);
fuse_put_request(ff->fc, ff->reserved_req);
kfree(ff);
@@ -661,7 +664,12 @@
int nr_alloc = min_t(unsigned, data->nr_pages,
FUSE_MAX_PAGES_PER_REQ);
fuse_send_readpages(req, data->file);
- data->req = req = fuse_get_req(fc, nr_alloc);
+ if (fc->async_read)
+ req = fuse_get_req_for_background(fc, nr_alloc);
+ else
+ req = fuse_get_req(fc, nr_alloc);
+
+ data->req = req;
if (IS_ERR(req)) {
unlock_page(page);
return PTR_ERR(req);
@@ -696,7 +704,10 @@
data.file = file;
data.inode = inode;
- data.req = fuse_get_req(fc, nr_alloc);
+ if (fc->async_read)
+ data.req = fuse_get_req_for_background(fc, nr_alloc);
+ else
+ data.req = fuse_get_req(fc, nr_alloc);
data.nr_pages = nr_pages;
err = PTR_ERR(data.req);
if (IS_ERR(data.req))
@@ -1375,6 +1386,7 @@
if (!req)
goto err;
+ req->background = 1; /* writeback always goes to bg_queue */
tmp_page = alloc_page(GFP_NOFS | __GFP_HIGHMEM);
if (!tmp_page)
goto err_free;
diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h
index 6aeba86..47c94d2 100644
--- a/fs/fuse/fuse_i.h
+++ b/fs/fuse/fuse_i.h
@@ -708,6 +708,8 @@
* caller should specify # elements in req->pages[] explicitly
*/
struct fuse_req *fuse_get_req(struct fuse_conn *fc, unsigned npages);
+struct fuse_req *fuse_get_req_for_background(struct fuse_conn *fc,
+ unsigned npages);
/**
* Get a request, may fail with -ENOMEM,
diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c
index 137185c..e26607d 100644
--- a/fs/fuse/inode.c
+++ b/fs/fuse/inode.c
@@ -346,6 +346,7 @@
fc->destroy_req = NULL;
req->in.h.opcode = FUSE_DESTROY;
req->force = 1;
+ req->background = 0;
fuse_request_send(fc, req);
fuse_put_request(fc, req);
}
@@ -1043,6 +1044,7 @@
init_req = fuse_request_alloc(0);
if (!init_req)
goto err_put_root;
+ init_req->background = 1;
if (is_bdev) {
fc->destroy_req = fuse_request_alloc(0);