Commit d333fc8d authored by Linus Torvalds's avatar Linus Torvalds

Merge branch 'fixes' of git://git.linux-nfs.org/pub/linux/nfs-2.6

* 'fixes' of git://git.linux-nfs.org/pub/linux/nfs-2.6:
  NFS: Fix nfs_direct_dirty_pages()
  NFS: Fix handful of compiler warnings in direct.c
  NFS: Avoid a deadlock situation on write
parents 1a93fa86 d4a8f367
......@@ -122,19 +122,25 @@ ssize_t nfs_direct_IO(int rw, struct kiocb *iocb, const struct iovec *iov, loff_
return -EINVAL;
}
static void nfs_direct_dirty_pages(struct page **pages, int npages)
static void nfs_direct_dirty_pages(struct page **pages, unsigned int pgbase, size_t count)
{
int i;
unsigned int npages;
unsigned int i;
if (count == 0)
return;
pages += (pgbase >> PAGE_SHIFT);
npages = (count + (pgbase & ~PAGE_MASK) + PAGE_SIZE - 1) >> PAGE_SHIFT;
for (i = 0; i < npages; i++) {
struct page *page = pages[i];
if (!PageCompound(page))
set_page_dirty_lock(page);
set_page_dirty(page);
}
}
static void nfs_direct_release_pages(struct page **pages, int npages)
static void nfs_direct_release_pages(struct page **pages, unsigned int npages)
{
int i;
unsigned int i;
for (i = 0; i < npages; i++)
page_cache_release(pages[i]);
}
......@@ -224,17 +230,18 @@ static void nfs_direct_read_result(struct rpc_task *task, void *calldata)
if (nfs_readpage_result(task, data) != 0)
return;
nfs_direct_dirty_pages(data->pagevec, data->npages);
nfs_direct_release_pages(data->pagevec, data->npages);
spin_lock(&dreq->lock);
if (likely(task->tk_status >= 0))
dreq->count += data->res.count;
else
if (unlikely(task->tk_status < 0)) {
dreq->error = task->tk_status;
spin_unlock(&dreq->lock);
spin_unlock(&dreq->lock);
} else {
dreq->count += data->res.count;
spin_unlock(&dreq->lock);
nfs_direct_dirty_pages(data->pagevec,
data->args.pgbase,
data->res.count);
}
nfs_direct_release_pages(data->pagevec, data->npages);
if (put_dreq(dreq))
nfs_direct_complete(dreq);
......@@ -279,9 +286,12 @@ static ssize_t nfs_direct_read_schedule(struct nfs_direct_req *dreq, unsigned lo
result = get_user_pages(current, current->mm, user_addr,
data->npages, 1, 0, data->pagevec, NULL);
up_read(&current->mm->mmap_sem);
if (unlikely(result < data->npages)) {
if (result > 0)
nfs_direct_release_pages(data->pagevec, result);
if (result < 0) {
nfs_readdata_release(data);
break;
}
if ((unsigned)result < data->npages) {
nfs_direct_release_pages(data->pagevec, result);
nfs_readdata_release(data);
break;
}
......@@ -610,9 +620,12 @@ static ssize_t nfs_direct_write_schedule(struct nfs_direct_req *dreq, unsigned l
result = get_user_pages(current, current->mm, user_addr,
data->npages, 0, 0, data->pagevec, NULL);
up_read(&current->mm->mmap_sem);
if (unlikely(result < data->npages)) {
if (result > 0)
nfs_direct_release_pages(data->pagevec, result);
if (result < 0) {
nfs_writedata_release(data);
break;
}
if ((unsigned)result < data->npages) {
nfs_direct_release_pages(data->pagevec, result);
nfs_writedata_release(data);
break;
}
......
......@@ -355,6 +355,26 @@ void nfs_pageio_complete(struct nfs_pageio_descriptor *desc)
nfs_pageio_doio(desc);
}
/**
* nfs_pageio_cond_complete - Conditional I/O completion
* @desc: pointer to io descriptor
* @index: page index
*
* It is important to ensure that processes don't try to take locks
* on non-contiguous ranges of pages as that might deadlock. This
* function should be called before attempting to wait on a locked
* nfs_page. It will complete the I/O if the page index 'index'
* is not contiguous with the existing list of pages in 'desc'.
*/
void nfs_pageio_cond_complete(struct nfs_pageio_descriptor *desc, pgoff_t index)
{
if (!list_empty(&desc->pg_list)) {
struct nfs_page *prev = nfs_list_entry(desc->pg_list.prev);
if (index != prev->wb_index + 1)
nfs_pageio_doio(desc);
}
}
#define NFS_SCAN_MAXENTRIES 16
/**
* nfs_scan_list - Scan a list for matching requests
......
......@@ -273,8 +273,6 @@ static int nfs_page_async_flush(struct nfs_pageio_descriptor *pgio,
* request as dirty (in which case we don't care).
*/
spin_unlock(req_lock);
/* Prevent deadlock! */
nfs_pageio_complete(pgio);
ret = nfs_wait_on_request(req);
nfs_release_request(req);
if (ret != 0)
......@@ -321,6 +319,8 @@ static int nfs_writepage_locked(struct page *page, struct writeback_control *wbc
pgio = &mypgio;
}
nfs_pageio_cond_complete(pgio, page->index);
err = nfs_page_async_flush(pgio, page);
if (err <= 0)
goto out;
......@@ -329,6 +329,8 @@ static int nfs_writepage_locked(struct page *page, struct writeback_control *wbc
if (!offset)
goto out;
nfs_pageio_cond_complete(pgio, page->index);
ctx = nfs_find_open_context(inode, NULL, FMODE_WRITE);
if (ctx == NULL) {
err = -EBADF;
......
......@@ -81,6 +81,7 @@ extern void nfs_pageio_init(struct nfs_pageio_descriptor *desc,
extern int nfs_pageio_add_request(struct nfs_pageio_descriptor *,
struct nfs_page *);
extern void nfs_pageio_complete(struct nfs_pageio_descriptor *desc);
extern void nfs_pageio_cond_complete(struct nfs_pageio_descriptor *, pgoff_t);
extern int nfs_wait_on_request(struct nfs_page *);
extern void nfs_unlock_request(struct nfs_page *req);
extern int nfs_set_page_writeback_locked(struct nfs_page *req);
......
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