The patch removes inline array of FUSE_MAX_PAGES_PER_REQ page pointers from
fuse_req. Instead of that, req->pages may now point either to small inline
array or to an array allocated dynamically.

This essentially means that all callers of fuse_request_alloc[_nofs] should
pass the number of pages needed explicitly.

The patch doesn't make any logic changes.
---
 fs/fuse/dev.c    |   40 ++++++++++++++++++++++++++++++----------
 fs/fuse/file.c   |    4 ++--
 fs/fuse/fuse_i.h |    9 ++++++---
 fs/fuse/inode.c  |    4 ++--
 4 files changed, 40 insertions(+), 17 deletions(-)

diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
index 7df2b5e..c0283a1 100644
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -36,32 +36,52 @@ static struct fuse_conn *fuse_get_conn(struct file *file)
 
 static void fuse_request_init(struct fuse_req *req)
 {
+       struct page **pages = req->pages;
+
        memset(req, 0, sizeof(*req));
        INIT_LIST_HEAD(&req->list);
        INIT_LIST_HEAD(&req->intr_entry);
        init_waitqueue_head(&req->waitq);
        atomic_set(&req->count, 1);
+
+       req->pages = pages;
 }
 
-struct fuse_req *fuse_request_alloc(void)
+static struct fuse_req *__fuse_request_alloc(int npages, gfp_t flags)
 {
-       struct fuse_req *req = kmem_cache_alloc(fuse_req_cachep, GFP_KERNEL);
-       if (req)
+       struct fuse_req *req = kmem_cache_alloc(fuse_req_cachep, flags);
+       if (req) {
+               if (npages <= 1)
+                       req->pages = req->inline_pages;
+               else
+                       req->pages = kmalloc(sizeof(struct page *) * npages,
+                                            flags);
+
+               if (!req->pages) {
+                       kmem_cache_free(fuse_req_cachep, req);
+                       return NULL;
+               }
+
                fuse_request_init(req);
+       }
        return req;
 }
+
+struct fuse_req *fuse_request_alloc(int 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(int 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 +136,7 @@ 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;
@@ -193,7 +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);
 
diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index aba15f1..7423ea4 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -57,7 +57,7 @@ struct fuse_file *fuse_file_alloc(struct fuse_conn *fc)
                return NULL;
 
        ff->fc = fc;
-       ff->reserved_req = fuse_request_alloc();
+       ff->reserved_req = fuse_request_alloc(0);
        if (unlikely(!ff->reserved_req)) {
                kfree(ff);
                return NULL;
@@ -1272,7 +1272,7 @@ static int fuse_writepage_locked(struct page *page)
 
        set_page_writeback(page);
 
-       req = fuse_request_alloc_nofs();
+       req = fuse_request_alloc_nofs(1);
        if (!req)
                goto err;
 
diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h
index e24dd74..5e78840 100644
--- a/fs/fuse/fuse_i.h
+++ b/fs/fuse/fuse_i.h
@@ -291,7 +291,10 @@ struct fuse_req {
        } misc;
 
        /** page vector */
-       struct page *pages[FUSE_MAX_PAGES_PER_REQ];
+       struct page **pages;
+
+       /** inline page vector */
+       struct page *inline_pages[1];
 
        /** number of pages in vector */
        unsigned num_pages;
@@ -658,9 +661,9 @@ void fuse_ctl_cleanup(void);
 /**
  * Allocate a request
  */
-struct fuse_req *fuse_request_alloc(void);
+struct fuse_req *fuse_request_alloc(int npages);
 
-struct fuse_req *fuse_request_alloc_nofs(void);
+struct fuse_req *fuse_request_alloc_nofs(int npages);
 
 /**
  * Free a request
diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c
index ce0a283..3f399ba 100644
--- a/fs/fuse/inode.c
+++ b/fs/fuse/inode.c
@@ -1027,12 +1027,12 @@ static int fuse_fill_super(struct super_block *sb, void 
*data, int silent)
        /* only now - we want root dentry with NULL ->d_op */
        sb->s_d_op = &fuse_dentry_operations;
 
-       init_req = fuse_request_alloc();
+       init_req = fuse_request_alloc(0);
        if (!init_req)
                goto err_put_root;
 
        if (is_bdev) {
-               fc->destroy_req = fuse_request_alloc();
+               fc->destroy_req = fuse_request_alloc(0);
                if (!fc->destroy_req)
                        goto err_free_init_req;
        }

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to