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
......@@ -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);
......
......@@ -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;
......
......@@ -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
......
......@@ -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;
}
......
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment