fuse: general infrastructure for pages[] of variable size

[karo-tx-linux.git] / fs / fuse / dev.c

diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
index 05c3eec298f2e5f6d74df583340923bfce4d8247..af37ae138252acaa8892ce6d598adab10534f9cf 100644 (file)
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -34,34 +34,55 @@ static struct fuse_conn *fuse_get_conn(struct file *file)
        return file->private_data;
 }
 
-static void fuse_request_init(struct fuse_req *req)
+static void fuse_request_init(struct fuse_req *req, struct page **pages,
+                             unsigned npages)
 {
        memset(req, 0, sizeof(*req));
+       memset(pages, 0, sizeof(*pages) * npages);
        INIT_LIST_HEAD(&req->list);
        INIT_LIST_HEAD(&req->intr_entry);
        init_waitqueue_head(&req->waitq);
        atomic_set(&req->count, 1);
+       req->pages = pages;
+       req->max_pages = npages;
 }
 
-struct fuse_req *fuse_request_alloc(void)
+static struct fuse_req *__fuse_request_alloc(unsigned npages, gfp_t flags)
 {
-       struct fuse_req *req = kmem_cache_alloc(fuse_req_cachep, GFP_KERNEL);
-       if (req)
-               fuse_request_init(req);
+       struct fuse_req *req = kmem_cache_alloc(fuse_req_cachep, flags);
+       if (req) {
+               struct page **pages;
+
+               if (npages <= FUSE_REQ_INLINE_PAGES)
+                       pages = req->inline_pages;
+               else
+                       pages = kmalloc(sizeof(struct page *) * npages, flags);
+
+               if (!pages) {
+                       kmem_cache_free(fuse_req_cachep, req);
+                       return NULL;
+               }
+
+               fuse_request_init(req, pages, npages);
+       }
        return req;
 }
+
+struct fuse_req *fuse_request_alloc(unsigned npages)
+{
+       return __fuse_request_alloc(npages, GFP_KERNEL);
+}
 EXPORT_SYMBOL_GPL(fuse_request_alloc);
 
-struct fuse_req *fuse_request_alloc_nofs(void)
+struct fuse_req *fuse_request_alloc_nofs(unsigned npages)
 {
-       struct fuse_req *req = kmem_cache_alloc(fuse_req_cachep, GFP_NOFS);
-       if (req)
-               fuse_request_init(req);
-       return req;
+       return __fuse_request_alloc(npages, GFP_NOFS);
 }
 
 void fuse_request_free(struct fuse_req *req)
 {
+       if (req->pages != req->inline_pages)
+               kfree(req->pages);
        kmem_cache_free(fuse_req_cachep, req);
 }
 
@@ -116,7 +137,7 @@ struct fuse_req *fuse_get_req(struct fuse_conn *fc)
        if (!fc->connected)
                goto out;
 
-       req = fuse_request_alloc();
+       req = fuse_request_alloc(FUSE_MAX_PAGES_PER_REQ);
        err = -ENOMEM;
        if (!req)
                goto out;
@@ -165,7 +186,7 @@ static void put_reserved_req(struct fuse_conn *fc, struct fuse_req *req)
        struct fuse_file *ff = file->private_data;
 
        spin_lock(&fc->lock);
-       fuse_request_init(req);
+       fuse_request_init(req, req->pages, req->max_pages);
        BUG_ON(ff->reserved_req);
        ff->reserved_req = req;
        wake_up_all(&fc->reserved_req_waitq);
@@ -192,7 +213,7 @@ struct fuse_req *fuse_get_req_nofail(struct fuse_conn *fc, struct file *file)
 
        atomic_inc(&fc->num_waiting);
        wait_event(fc->blocked_waitq, !fc->blocked);
-       req = fuse_request_alloc();
+       req = fuse_request_alloc(FUSE_MAX_PAGES_PER_REQ);
        if (!req)
                req = get_reserved_req(fc, file);