struct kref kref; /* release manager */
/* I/O parameters */
- struct list_head list, /* nfs_read/write_data structs */
- rewrite_list; /* saved nfs_write_data structs */
struct nfs_open_context *ctx; /* file open context info */
struct kiocb * iocb; /* controlling i/o request */
struct inode * inode; /* target file of i/o */
struct completion completion; /* wait for i/o completion */
/* commit state */
+ struct list_head rewrite_list; /* saved nfs_write_data structs */
struct nfs_write_data * commit_data; /* special write_data for commits */
int flags;
#define NFS_ODIRECT_DO_COMMIT (1) /* an unstable reply was received */
return page_count;
}
+static inline unsigned int nfs_max_pages(unsigned int size)
+{
+ return (size + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
+}
+
/**
* nfs_direct_IO - NFS address space operation for direct I/O
* @rw: direction (read or write)
return NULL;
kref_init(&dreq->kref);
+ kref_get(&dreq->kref);
init_completion(&dreq->completion);
- INIT_LIST_HEAD(&dreq->list);
INIT_LIST_HEAD(&dreq->rewrite_list);
dreq->iocb = NULL;
dreq->ctx = NULL;
kref_put(&dreq->kref, nfs_direct_req_release);
}
-/*
- * Note we also set the number of requests we have in the dreq when we are
- * done. This prevents races with I/O completion so we will always wait
- * until all requests have been dispatched and completed.
- */
-static struct nfs_direct_req *nfs_direct_read_alloc(size_t nbytes, size_t rsize)
-{
- struct list_head *list;
- struct nfs_direct_req *dreq;
- unsigned int rpages = (rsize + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
-
- dreq = nfs_direct_req_alloc();
- if (!dreq)
- return NULL;
-
- list = &dreq->list;
- for(;;) {
- struct nfs_read_data *data = nfs_readdata_alloc(rpages);
-
- if (unlikely(!data)) {
- while (!list_empty(list)) {
- data = list_entry(list->next,
- struct nfs_read_data, pages);
- list_del(&data->pages);
- nfs_readdata_free(data);
- }
- kref_put(&dreq->kref, nfs_direct_req_release);
- return NULL;
- }
-
- INIT_LIST_HEAD(&data->pages);
- list_add(&data->pages, list);
-
- data->req = (struct nfs_page *) dreq;
- get_dreq(dreq);
- if (nbytes <= rsize)
- break;
- nbytes -= rsize;
- }
- kref_get(&dreq->kref);
- return dreq;
-}
-
/*
* We must hold a reference to all the pages in this direct read request
* until the RPCs complete. This could be long *after* we are woken up in
};
/*
- * For each nfs_read_data struct that was allocated on the list, dispatch
- * an NFS READ operation. If get_user_pages() fails, we stop sending reads.
- * Read length accounting is handled by nfs_direct_read_result().
- * Otherwise, if no requests have been sent, just return an error.
+ * For each rsize'd chunk of the user's buffer, dispatch an NFS READ
+ * operation. If nfs_readdata_alloc() or get_user_pages() fails,
+ * bail and stop sending more reads. Read length accounting is
+ * handled automatically by nfs_direct_read_result(). Otherwise, if
+ * no requests have been sent, just return an error.
*/
static ssize_t nfs_direct_read_schedule(struct nfs_direct_req *dreq, unsigned long user_addr, size_t count, loff_t pos)
{
struct nfs_open_context *ctx = dreq->ctx;
struct inode *inode = ctx->dentry->d_inode;
- struct list_head *list = &dreq->list;
size_t rsize = NFS_SERVER(inode)->rsize;
+ unsigned int rpages = nfs_max_pages(rsize);
unsigned int pgbase;
int result;
ssize_t started = 0;
- struct nfs_read_data *data;
+
+ get_dreq(dreq);
pgbase = user_addr & ~PAGE_MASK;
do {
+ struct nfs_read_data *data;
size_t bytes;
+ result = -ENOMEM;
+ data = nfs_readdata_alloc(rpages);
+ if (unlikely(!data))
+ break;
+
bytes = rsize;
if (count < rsize)
bytes = count;
- BUG_ON(list_empty(list));
- data = list_entry(list->next, struct nfs_read_data, pages);
- list_del_init(&data->pages);
-
data->npages = nfs_direct_count_pages(user_addr, bytes);
down_read(¤t->mm->mmap_sem);
result = get_user_pages(current, current->mm, user_addr,
data->npages, 1, 0, data->pagevec, NULL);
up_read(¤t->mm->mmap_sem);
- if (unlikely(result < data->npages))
- goto out_err;
+ if (unlikely(result < data->npages)) {
+ if (result > 0)
+ nfs_direct_release_pages(data->pagevec, result);
+ nfs_readdata_release(data);
+ break;
+ }
+ get_dreq(dreq);
+
+ data->req = (struct nfs_page *) dreq;
data->inode = inode;
data->cred = ctx->cred;
data->args.fh = NFS_FH(inode);
count -= bytes;
} while (count != 0);
- BUG_ON(!list_empty(list));
- return 0;
-out_err:
- if (result > 0)
- nfs_direct_release_pages(data->pagevec, result);
-
- list_add(&data->pages, list);
- while (!list_empty(list)) {
- data = list_entry(list->next, struct nfs_read_data, pages);
- list_del(&data->pages);
- nfs_readdata_free(data);
- if (put_dreq(dreq))
- nfs_direct_complete(dreq);
- }
+ if (put_dreq(dreq))
+ nfs_direct_complete(dreq);
if (started)
return 0;
static ssize_t nfs_direct_read(struct kiocb *iocb, unsigned long user_addr, size_t count, loff_t pos)
{
- ssize_t result;
+ ssize_t result = 0;
sigset_t oldset;
struct inode *inode = iocb->ki_filp->f_mapping->host;
struct rpc_clnt *clnt = NFS_CLIENT(inode);
struct nfs_direct_req *dreq;
- dreq = nfs_direct_read_alloc(count, NFS_SERVER(inode)->rsize);
+ dreq = nfs_direct_req_alloc();
if (!dreq)
return -ENOMEM;
static void nfs_direct_free_writedata(struct nfs_direct_req *dreq)
{
- list_splice_init(&dreq->rewrite_list, &dreq->list);
- while (!list_empty(&dreq->list)) {
- struct nfs_write_data *data = list_entry(dreq->list.next, struct nfs_write_data, pages);
+ while (!list_empty(&dreq->rewrite_list)) {
+ struct nfs_write_data *data = list_entry(dreq->rewrite_list.next, struct nfs_write_data, pages);
list_del(&data->pages);
nfs_direct_release_pages(data->pagevec, data->npages);
nfs_writedata_release(data);
}
#endif
-static struct nfs_direct_req *nfs_direct_write_alloc(size_t nbytes, size_t wsize)
-{
- struct list_head *list;
- struct nfs_direct_req *dreq;
- unsigned int wpages = (wsize + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
-
- dreq = nfs_direct_req_alloc();
- if (!dreq)
- return NULL;
-
- list = &dreq->list;
- for(;;) {
- struct nfs_write_data *data = nfs_writedata_alloc(wpages);
-
- if (unlikely(!data)) {
- while (!list_empty(list)) {
- data = list_entry(list->next,
- struct nfs_write_data, pages);
- list_del(&data->pages);
- nfs_writedata_free(data);
- }
- kref_put(&dreq->kref, nfs_direct_req_release);
- return NULL;
- }
-
- INIT_LIST_HEAD(&data->pages);
- list_add(&data->pages, list);
-
- data->req = (struct nfs_page *) dreq;
- get_dreq(dreq);
- if (nbytes <= wsize)
- break;
- nbytes -= wsize;
- }
-
- nfs_alloc_commit_data(dreq);
-
- kref_get(&dreq->kref);
- return dreq;
-}
-
static void nfs_direct_write_result(struct rpc_task *task, void *calldata)
{
struct nfs_write_data *data = calldata;
};
/*
- * For each nfs_write_data struct that was allocated on the list, dispatch
- * an NFS WRITE operation. If get_user_pages() fails, we stop sending writes.
- * Write length accounting is handled by nfs_direct_write_result().
- * Otherwise, if no requests have been sent, just return an error.
+ * For each wsize'd chunk of the user's buffer, dispatch an NFS WRITE
+ * operation. If nfs_writedata_alloc() or get_user_pages() fails,
+ * bail and stop sending more writes. Write length accounting is
+ * handled automatically by nfs_direct_write_result(). Otherwise, if
+ * no requests have been sent, just return an error.
*/
static ssize_t nfs_direct_write_schedule(struct nfs_direct_req *dreq, unsigned long user_addr, size_t count, loff_t pos, int sync)
{
struct nfs_open_context *ctx = dreq->ctx;
struct inode *inode = ctx->dentry->d_inode;
- struct list_head *list = &dreq->list;
size_t wsize = NFS_SERVER(inode)->wsize;
+ unsigned int wpages = nfs_max_pages(wsize);
unsigned int pgbase;
int result;
ssize_t started = 0;
- struct nfs_write_data *data;
+
+ get_dreq(dreq);
pgbase = user_addr & ~PAGE_MASK;
do {
+ struct nfs_write_data *data;
size_t bytes;
+ result = -ENOMEM;
+ data = nfs_writedata_alloc(wpages);
+ if (unlikely(!data))
+ break;
+
bytes = wsize;
if (count < wsize)
bytes = count;
- BUG_ON(list_empty(list));
- data = list_entry(list->next, struct nfs_write_data, pages);
-
data->npages = nfs_direct_count_pages(user_addr, bytes);
down_read(¤t->mm->mmap_sem);
result = get_user_pages(current, current->mm, user_addr,
data->npages, 0, 0, data->pagevec, NULL);
up_read(¤t->mm->mmap_sem);
- if (unlikely(result < data->npages))
- goto out_err;
+ if (unlikely(result < data->npages)) {
+ if (result > 0)
+ nfs_direct_release_pages(data->pagevec, result);
+ nfs_writedata_release(data);
+ break;
+ }
+
+ get_dreq(dreq);
list_move_tail(&data->pages, &dreq->rewrite_list);
+ data->req = (struct nfs_page *) dreq;
data->inode = inode;
data->cred = ctx->cred;
data->args.fh = NFS_FH(inode);
count -= bytes;
} while (count != 0);
- BUG_ON(!list_empty(list));
- return 0;
-
-out_err:
- if (result > 0)
- nfs_direct_release_pages(data->pagevec, result);
- list_add(&data->pages, list);
- while (!list_empty(list)) {
- data = list_entry(list->next, struct nfs_write_data, pages);
- list_del(&data->pages);
- nfs_writedata_free(data);
- if (put_dreq(dreq))
- nfs_direct_write_complete(dreq, inode);
- }
+ if (put_dreq(dreq))
+ nfs_direct_write_complete(dreq, inode);
if (started)
return 0;
static ssize_t nfs_direct_write(struct kiocb *iocb, unsigned long user_addr, size_t count, loff_t pos)
{
- ssize_t result;
+ ssize_t result = 0;
sigset_t oldset;
struct inode *inode = iocb->ki_filp->f_mapping->host;
struct rpc_clnt *clnt = NFS_CLIENT(inode);
size_t wsize = NFS_SERVER(inode)->wsize;
int sync = 0;
- dreq = nfs_direct_write_alloc(count, wsize);
+ dreq = nfs_direct_req_alloc();
if (!dreq)
return -ENOMEM;
+ nfs_alloc_commit_data(dreq);
+
if (dreq->commit_data == NULL || count < wsize)
sync = FLUSH_STABLE;
projects / linux-2.6 / commitdiff