/*
* Local function declarations
*/
-static struct nfs_page * nfs_update_request(struct nfs_open_context*,
- struct page *,
- unsigned int, unsigned int);
static void nfs_pageio_init_write(struct nfs_pageio_descriptor *desc,
struct inode *inode, int ioflags);
static void nfs_redirty_request(struct nfs_page *req);
static void nfs_grow_file(struct page *page, unsigned int offset, unsigned int count)
{
struct inode *inode = page->mapping->host;
- loff_t end, i_size = i_size_read(inode);
- pgoff_t end_index = (i_size - 1) >> PAGE_CACHE_SHIFT;
+ loff_t end, i_size;
+ pgoff_t end_index;
+ spin_lock(&inode->i_lock);
+ i_size = i_size_read(inode);
+ end_index = (i_size - 1) >> PAGE_CACHE_SHIFT;
if (i_size > 0 && page->index < end_index)
- return;
+ goto out;
end = ((loff_t)page->index << PAGE_CACHE_SHIFT) + ((loff_t)offset+count);
if (i_size >= end)
- return;
- nfs_inc_stats(inode, NFSIOS_EXTENDWRITE);
+ goto out;
i_size_write(inode, end);
+ nfs_inc_stats(inode, NFSIOS_EXTENDWRITE);
+out:
+ spin_unlock(&inode->i_lock);
}
/* A writeback failed: mark the page as bad, and invalidate the page cache */
SetPageUptodate(page);
}
-static int nfs_writepage_setup(struct nfs_open_context *ctx, struct page *page,
- unsigned int offset, unsigned int count)
-{
- struct nfs_page *req;
- int ret;
-
- for (;;) {
- req = nfs_update_request(ctx, page, offset, count);
- if (!IS_ERR(req))
- break;
- ret = PTR_ERR(req);
- if (ret != -EBUSY)
- return ret;
- ret = nfs_wb_page(page->mapping->host, page);
- if (ret != 0)
- return ret;
- }
- /* Update file length */
- nfs_grow_file(page, offset, count);
- nfs_clear_page_tag_locked(req);
- return 0;
-}
-
static int wb_priority(struct writeback_control *wbc)
{
if (wbc->for_reclaim)
return ret;
spin_lock(&inode->i_lock);
}
- if (test_bit(PG_NEED_COMMIT, &req->wb_flags)) {
- /* This request is marked for commit */
+ if (test_bit(PG_CLEAN, &req->wb_flags)) {
spin_unlock(&inode->i_lock);
- nfs_clear_page_tag_locked(req);
- nfs_pageio_complete(pgio);
- return 0;
+ BUG();
}
if (nfs_set_page_writeback(page) != 0) {
spin_unlock(&inode->i_lock);
/*
* Insert a write request into an inode
*/
-static void nfs_inode_add_request(struct inode *inode, struct nfs_page *req)
+static int nfs_inode_add_request(struct inode *inode, struct nfs_page *req)
{
struct nfs_inode *nfsi = NFS_I(inode);
int error;
+ error = radix_tree_preload(GFP_NOFS);
+ if (error != 0)
+ goto out;
+
+ /* Lock the request! */
+ nfs_lock_request_dontget(req);
+
+ spin_lock(&inode->i_lock);
error = radix_tree_insert(&nfsi->nfs_page_tree, req->wb_index, req);
BUG_ON(error);
if (!nfsi->npages) {
kref_get(&req->wb_kref);
radix_tree_tag_set(&nfsi->nfs_page_tree, req->wb_index,
NFS_PAGE_TAG_LOCKED);
+ spin_unlock(&inode->i_lock);
+ radix_tree_preload_end();
+out:
+ return error;
}
/*
__set_page_dirty_nobuffers(req->wb_page);
}
-/*
- * Check if a request is dirty
- */
-static inline int
-nfs_dirty_request(struct nfs_page *req)
-{
- struct page *page = req->wb_page;
-
- if (page == NULL || test_bit(PG_NEED_COMMIT, &req->wb_flags))
- return 0;
- return !PageWriteback(page);
-}
-
#if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4)
/*
* Add a request to the inode's commit list.
spin_lock(&inode->i_lock);
nfsi->ncommit++;
- set_bit(PG_NEED_COMMIT, &(req)->wb_flags);
+ set_bit(PG_CLEAN, &(req)->wb_flags);
radix_tree_tag_set(&nfsi->nfs_page_tree,
req->wb_index,
NFS_PAGE_TAG_COMMIT);
__mark_inode_dirty(inode, I_DIRTY_DATASYNC);
}
+static int
+nfs_clear_request_commit(struct nfs_page *req)
+{
+ struct page *page = req->wb_page;
+
+ if (test_and_clear_bit(PG_CLEAN, &(req)->wb_flags)) {
+ dec_zone_page_state(page, NR_UNSTABLE_NFS);
+ dec_bdi_stat(page->mapping->backing_dev_info, BDI_RECLAIMABLE);
+ return 1;
+ }
+ return 0;
+}
+
static inline
int nfs_write_need_commit(struct nfs_write_data *data)
{
static inline
int nfs_reschedule_unstable_write(struct nfs_page *req)
{
- if (test_bit(PG_NEED_COMMIT, &req->wb_flags)) {
+ if (test_and_clear_bit(PG_NEED_COMMIT, &req->wb_flags)) {
nfs_mark_request_commit(req);
return 1;
}
{
}
+static inline int
+nfs_clear_request_commit(struct nfs_page *req)
+{
+ return 0;
+}
+
static inline
int nfs_write_need_commit(struct nfs_write_data *data)
{
while(!list_empty(head)) {
req = nfs_list_entry(head->next);
- dec_zone_page_state(req->wb_page, NR_UNSTABLE_NFS);
- dec_bdi_stat(req->wb_page->mapping->backing_dev_info,
- BDI_RECLAIMABLE);
nfs_list_remove_request(req);
- clear_bit(PG_NEED_COMMIT, &(req)->wb_flags);
+ nfs_clear_request_commit(req);
nfs_inode_remove_request(req);
nfs_unlock_request(req);
}
#endif
/*
- * Try to update any existing write request, or create one if there is none.
- * In order to match, the request's credentials must match those of
- * the calling process.
+ * Search for an existing write request, and attempt to update
+ * it to reflect a new dirty region on a given page.
*
- * Note: Should always be called with the Page Lock held!
+ * If the attempt fails, then the existing request is flushed out
+ * to disk.
*/
-static struct nfs_page * nfs_update_request(struct nfs_open_context* ctx,
- struct page *page, unsigned int offset, unsigned int bytes)
+static struct nfs_page *nfs_try_to_update_request(struct inode *inode,
+ struct page *page,
+ unsigned int offset,
+ unsigned int bytes)
{
- struct address_space *mapping = page->mapping;
- struct inode *inode = mapping->host;
- struct nfs_page *req, *new = NULL;
- pgoff_t rqend, end;
+ struct nfs_page *req;
+ unsigned int rqend;
+ unsigned int end;
+ int error;
+
+ if (!PagePrivate(page))
+ return NULL;
end = offset + bytes;
+ spin_lock(&inode->i_lock);
for (;;) {
- /* Loop over all inode entries and see if we find
- * A request for the page we wish to update
+ req = nfs_page_find_request_locked(page);
+ if (req == NULL)
+ goto out_unlock;
+
+ rqend = req->wb_offset + req->wb_bytes;
+ /*
+ * Tell the caller to flush out the request if
+ * the offsets are non-contiguous.
+ * Note: nfs_flush_incompatible() will already
+ * have flushed out requests having wrong owners.
*/
- if (new) {
- if (radix_tree_preload(GFP_NOFS)) {
- nfs_release_request(new);
- return ERR_PTR(-ENOMEM);
- }
- }
+ if (offset > rqend
+ || end < req->wb_offset)
+ goto out_flushme;
- spin_lock(&inode->i_lock);
- req = nfs_page_find_request_locked(page);
- if (req) {
- if (!nfs_set_page_tag_locked(req)) {
- int error;
-
- spin_unlock(&inode->i_lock);
- error = nfs_wait_on_request(req);
- nfs_release_request(req);
- if (error < 0) {
- if (new) {
- radix_tree_preload_end();
- nfs_release_request(new);
- }
- return ERR_PTR(error);
- }
- continue;
- }
- spin_unlock(&inode->i_lock);
- if (new) {
- radix_tree_preload_end();
- nfs_release_request(new);
- }
+ if (nfs_set_page_tag_locked(req))
break;
- }
- if (new) {
- nfs_lock_request_dontget(new);
- nfs_inode_add_request(inode, new);
- spin_unlock(&inode->i_lock);
- radix_tree_preload_end();
- req = new;
- goto zero_page;
- }
+ /* The request is locked, so wait and then retry */
spin_unlock(&inode->i_lock);
-
- new = nfs_create_request(ctx, inode, page, offset, bytes);
- if (IS_ERR(new))
- return new;
+ error = nfs_wait_on_request(req);
+ nfs_release_request(req);
+ if (error != 0)
+ goto out_err;
+ spin_lock(&inode->i_lock);
}
- /* We have a request for our page.
- * If the creds don't match, or the
- * page addresses don't match,
- * tell the caller to wait on the conflicting
- * request.
- */
- rqend = req->wb_offset + req->wb_bytes;
- if (req->wb_context != ctx
- || req->wb_page != page
- || !nfs_dirty_request(req)
- || offset > rqend || end < req->wb_offset) {
- nfs_clear_page_tag_locked(req);
- return ERR_PTR(-EBUSY);
- }
+ if (nfs_clear_request_commit(req))
+ radix_tree_tag_clear(&NFS_I(inode)->nfs_page_tree,
+ req->wb_index, NFS_PAGE_TAG_COMMIT);
/* Okay, the request matches. Update the region */
if (offset < req->wb_offset) {
req->wb_offset = offset;
req->wb_pgbase = offset;
- req->wb_bytes = max(end, rqend) - req->wb_offset;
- goto zero_page;
}
-
if (end > rqend)
req->wb_bytes = end - req->wb_offset;
-
+ else
+ req->wb_bytes = rqend - req->wb_offset;
+out_unlock:
+ spin_unlock(&inode->i_lock);
return req;
-zero_page:
- /* If this page might potentially be marked as up to date,
- * then we need to zero any uninitalised data. */
- if (req->wb_pgbase == 0 && req->wb_bytes != PAGE_CACHE_SIZE
- && !PageUptodate(req->wb_page))
- zero_user_segment(req->wb_page, req->wb_bytes, PAGE_CACHE_SIZE);
+out_flushme:
+ spin_unlock(&inode->i_lock);
+ nfs_release_request(req);
+ error = nfs_wb_page(inode, page);
+out_err:
+ return ERR_PTR(error);
+}
+
+/*
+ * Try to update an existing write request, or create one if there is none.
+ *
+ * Note: Should always be called with the Page Lock held to prevent races
+ * if we have to add a new request. Also assumes that the caller has
+ * already called nfs_flush_incompatible() if necessary.
+ */
+static struct nfs_page * nfs_setup_write_request(struct nfs_open_context* ctx,
+ struct page *page, unsigned int offset, unsigned int bytes)
+{
+ struct inode *inode = page->mapping->host;
+ struct nfs_page *req;
+ int error;
+
+ req = nfs_try_to_update_request(inode, page, offset, bytes);
+ if (req != NULL)
+ goto out;
+ req = nfs_create_request(ctx, inode, page, offset, bytes);
+ if (IS_ERR(req))
+ goto out;
+ error = nfs_inode_add_request(inode, req);
+ if (error != 0) {
+ nfs_release_request(req);
+ req = ERR_PTR(error);
+ }
+out:
return req;
}
+static int nfs_writepage_setup(struct nfs_open_context *ctx, struct page *page,
+ unsigned int offset, unsigned int count)
+{
+ struct nfs_page *req;
+
+ req = nfs_setup_write_request(ctx, page, offset, count);
+ if (IS_ERR(req))
+ return PTR_ERR(req);
+ /* Update file length */
+ nfs_grow_file(page, offset, count);
+ nfs_mark_uptodate(page, req->wb_pgbase, req->wb_bytes);
+ nfs_clear_page_tag_locked(req);
+ return 0;
+}
+
int nfs_flush_incompatible(struct file *file, struct page *page)
{
struct nfs_open_context *ctx = nfs_file_open_context(file);
req = nfs_page_find_request(page);
if (req == NULL)
return 0;
- do_flush = req->wb_page != page || req->wb_context != ctx
- || !nfs_dirty_request(req);
+ do_flush = req->wb_page != page || req->wb_context != ctx;
nfs_release_request(req);
if (!do_flush)
return 0;
nfs_inc_stats(inode, NFSIOS_VFSUPDATEPAGE);
- dprintk("NFS: nfs_updatepage(%s/%s %d@%Ld)\n",
+ dprintk("NFS: nfs_updatepage(%s/%s %d@%lld)\n",
file->f_path.dentry->d_parent->d_name.name,
file->f_path.dentry->d_name.name, count,
- (long long)(page_offset(page) +offset));
+ (long long)(page_offset(page) + offset));
/* If we're not using byte range locks, and we know the page
* is up to date, it may be more efficient to extend the write
}
status = nfs_writepage_setup(ctx, page, offset, count);
- __set_page_dirty_nobuffers(page);
-
- dprintk("NFS: nfs_updatepage returns %d (isize %Ld)\n",
- status, (long long)i_size_read(inode));
if (status < 0)
nfs_set_pageerror(page);
+ else
+ __set_page_dirty_nobuffers(page);
+
+ dprintk("NFS: nfs_updatepage returns %d (isize %lld)\n",
+ status, (long long)i_size_read(inode));
return status;
}
static void nfs_writepage_release(struct nfs_page *req)
{
- if (PageError(req->wb_page)) {
- nfs_end_page_writeback(req->wb_page);
- nfs_inode_remove_request(req);
- } else if (!nfs_reschedule_unstable_write(req)) {
- /* Set the PG_uptodate flag */
- nfs_mark_uptodate(req->wb_page, req->wb_pgbase, req->wb_bytes);
+ if (PageError(req->wb_page) || !nfs_reschedule_unstable_write(req)) {
nfs_end_page_writeback(req->wb_page);
nfs_inode_remove_request(req);
} else
NFS_PROTO(inode)->write_setup(data, &msg);
dprintk("NFS: %5u initiated write call "
- "(req %s/%Ld, %u bytes @ offset %Lu)\n",
+ "(req %s/%lld, %u bytes @ offset %llu)\n",
data->task.tk_pid,
inode->i_sb->s_id,
(long long)NFS_FILEID(inode),
static void nfs_writeback_done_partial(struct rpc_task *task, void *calldata)
{
struct nfs_write_data *data = calldata;
- struct nfs_page *req = data->req;
- dprintk("NFS: write (%s/%Ld %d@%Ld)",
- req->wb_context->path.dentry->d_inode->i_sb->s_id,
- (long long)NFS_FILEID(req->wb_context->path.dentry->d_inode),
- req->wb_bytes,
- (long long)req_offset(req));
+ dprintk("NFS: %5u write(%s/%lld %d@%lld)",
+ task->tk_pid,
+ data->req->wb_context->path.dentry->d_inode->i_sb->s_id,
+ (long long)
+ NFS_FILEID(data->req->wb_context->path.dentry->d_inode),
+ data->req->wb_bytes, (long long)req_offset(data->req));
nfs_writeback_done(task, data);
}
nfs_list_remove_request(req);
- dprintk("NFS: write (%s/%Ld %d@%Ld)",
+ dprintk("NFS: %5u write (%s/%lld %d@%lld)",
+ data->task.tk_pid,
req->wb_context->path.dentry->d_inode->i_sb->s_id,
(long long)NFS_FILEID(req->wb_context->path.dentry->d_inode),
req->wb_bytes,
dprintk(" marked for commit\n");
goto next;
}
- /* Set the PG_uptodate flag? */
- nfs_mark_uptodate(page, req->wb_pgbase, req->wb_bytes);
dprintk(" OK\n");
remove_request:
nfs_end_page_writeback(page);
static unsigned long complain;
if (time_before(complain, jiffies)) {
- dprintk("NFS: faulty NFS server %s:"
+ dprintk("NFS: faulty NFS server %s:"
" (committed = %d) != (stable = %d)\n",
NFS_SERVER(data->inode)->nfs_client->cl_hostname,
resp->verf->committed, argp->stable);
while (!list_empty(&data->pages)) {
req = nfs_list_entry(data->pages.next);
nfs_list_remove_request(req);
- clear_bit(PG_NEED_COMMIT, &(req)->wb_flags);
- dec_zone_page_state(req->wb_page, NR_UNSTABLE_NFS);
- dec_bdi_stat(req->wb_page->mapping->backing_dev_info,
- BDI_RECLAIMABLE);
+ nfs_clear_request_commit(req);
- dprintk("NFS: commit (%s/%Ld %d@%Ld)",
+ dprintk("NFS: commit (%s/%lld %d@%lld)",
req->wb_context->path.dentry->d_inode->i_sb->s_id,
(long long)NFS_FILEID(req->wb_context->path.dentry->d_inode),
req->wb_bytes,
* returned by the server against all stored verfs. */
if (!memcmp(req->wb_verf.verifier, data->verf.verifier, sizeof(data->verf.verifier))) {
/* We have a match */
- /* Set the PG_uptodate flag */
- nfs_mark_uptodate(req->wb_page, req->wb_pgbase,
- req->wb_bytes);
nfs_inode_remove_request(req);
dprintk(" OK\n");
goto next;
req = nfs_page_find_request(page);
if (req == NULL)
goto out;
- if (test_bit(PG_NEED_COMMIT, &req->wb_flags)) {
+ if (test_bit(PG_CLEAN, &req->wb_flags)) {
nfs_release_request(req);
break;
}
git.openpandora.org / pandora-kernel.git / blobdiff