Commit 4250c066 authored by Maxim Patlasov's avatar Maxim Patlasov Committed by Miklos Szeredi
Browse files

fuse: general infrastructure for pages[] of variable size 



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.

Signed-off-by: default avatarMaxim Patlasov <mpatlasov@parallels.com>
Signed-off-by: default avatarMiklos Szeredi <mszeredi@suse.cz>
parent 0b05b183

fs/fuse/dev.c

+34 −13
Original line number Diff line number Diff line
@@ -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);

fs/fuse/file.c

+2 −2
Original line number Diff line number Diff line
@@ -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;

fs/fuse/fuse_i.h

+12 −3
Original line number Diff line number Diff line
@@ -44,6 +44,9 @@ 
    doing the mount will be allowed to access the filesystem */

#define FUSE_ALLOW_OTHER         (1 << 1)



/** Number of page pointers embedded in fuse_req */

#define FUSE_REQ_INLINE_PAGES 1



/** List of active connections */

extern struct list_head fuse_conn_list;
@@ -291,7 +294,13 @@ struct fuse_req { 
	} misc;



	/** page vector */

	struct page *pages[FUSE_MAX_PAGES_PER_REQ];

	struct page **pages;



	/** size of the 'pages' array */

	unsigned max_pages;



	/** inline page vector */

	struct page *inline_pages[FUSE_REQ_INLINE_PAGES];



	/** number of pages in vector */

	unsigned num_pages;
@@ -664,9 +673,9 @@ void fuse_ctl_cleanup(void); 
/**

 * Allocate a request

 */

struct fuse_req *fuse_request_alloc(void);

struct fuse_req *fuse_request_alloc(unsigned npages);



struct fuse_req *fuse_request_alloc_nofs(void);

struct fuse_req *fuse_request_alloc_nofs(unsigned npages);



/**

 * Free a request

fs/fuse/inode.c

+2 −2
Original line number Diff line number Diff line
@@ -1037,12 +1037,12 @@ 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;

	}

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