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Diffstat (limited to 'fs/nfs/file.c')
-rw-r--r--fs/nfs/file.c75
1 files changed, 57 insertions, 18 deletions
diff --git a/fs/nfs/file.c b/fs/nfs/file.c
index 90f292b520d..3523b895eb4 100644
--- a/fs/nfs/file.c
+++ b/fs/nfs/file.c
@@ -35,6 +35,7 @@
#include "delegation.h"
#include "internal.h"
#include "iostat.h"
+#include "fscache.h"
#define NFSDBG_FACILITY NFSDBG_FILE
@@ -64,11 +65,7 @@ const struct file_operations nfs_file_operations = {
.write = do_sync_write,
.aio_read = nfs_file_read,
.aio_write = nfs_file_write,
-#ifdef CONFIG_MMU
.mmap = nfs_file_mmap,
-#else
- .mmap = generic_file_mmap,
-#endif
.open = nfs_file_open,
.flush = nfs_file_flush,
.release = nfs_file_release,
@@ -141,9 +138,6 @@ nfs_file_release(struct inode *inode, struct file *filp)
dentry->d_parent->d_name.name,
dentry->d_name.name);
- /* Ensure that dirty pages are flushed out with the right creds */
- if (filp->f_mode & FMODE_WRITE)
- nfs_wb_all(dentry->d_inode);
nfs_inc_stats(inode, NFSIOS_VFSRELEASE);
return nfs_release(inode, filp);
}
@@ -235,7 +229,6 @@ nfs_file_flush(struct file *file, fl_owner_t id)
struct nfs_open_context *ctx = nfs_file_open_context(file);
struct dentry *dentry = file->f_path.dentry;
struct inode *inode = dentry->d_inode;
- int status;
dprintk("NFS: flush(%s/%s)\n",
dentry->d_parent->d_name.name,
@@ -245,11 +238,8 @@ nfs_file_flush(struct file *file, fl_owner_t id)
return 0;
nfs_inc_stats(inode, NFSIOS_VFSFLUSH);
- /* Ensure that data+attribute caches are up to date after close() */
- status = nfs_do_fsync(ctx, inode);
- if (!status)
- nfs_revalidate_inode(NFS_SERVER(inode), inode);
- return status;
+ /* Flush writes to the server and return any errors */
+ return nfs_do_fsync(ctx, inode);
}
static ssize_t
@@ -304,11 +294,13 @@ nfs_file_mmap(struct file * file, struct vm_area_struct * vma)
dprintk("NFS: mmap(%s/%s)\n",
dentry->d_parent->d_name.name, dentry->d_name.name);
- status = nfs_revalidate_mapping(inode, file->f_mapping);
+ /* Note: generic_file_mmap() returns ENOSYS on nommu systems
+ * so we call that before revalidating the mapping
+ */
+ status = generic_file_mmap(file, vma);
if (!status) {
vma->vm_ops = &nfs_file_vm_ops;
- vma->vm_flags |= VM_CAN_NONLINEAR;
- file_accessed(file);
+ status = nfs_revalidate_mapping(inode, file->f_mapping);
}
return status;
}
@@ -354,6 +346,15 @@ static int nfs_write_begin(struct file *file, struct address_space *mapping,
file->f_path.dentry->d_name.name,
mapping->host->i_ino, len, (long long) pos);
+ /*
+ * Prevent starvation issues if someone is doing a consistency
+ * sync-to-disk
+ */
+ ret = wait_on_bit(&NFS_I(mapping->host)->flags, NFS_INO_FLUSHING,
+ nfs_wait_bit_killable, TASK_KILLABLE);
+ if (ret)
+ return ret;
+
page = grab_cache_page_write_begin(mapping, index, flags);
if (!page)
return -ENOMEM;
@@ -409,6 +410,13 @@ static int nfs_write_end(struct file *file, struct address_space *mapping,
return copied;
}
+/*
+ * Partially or wholly invalidate a page
+ * - Release the private state associated with a page if undergoing complete
+ * page invalidation
+ * - Called if either PG_private or PG_fscache is set on the page
+ * - Caller holds page lock
+ */
static void nfs_invalidate_page(struct page *page, unsigned long offset)
{
dfprintk(PAGECACHE, "NFS: invalidate_page(%p, %lu)\n", page, offset);
@@ -417,23 +425,43 @@ static void nfs_invalidate_page(struct page *page, unsigned long offset)
return;
/* Cancel any unstarted writes on this page */
nfs_wb_page_cancel(page->mapping->host, page);
+
+ nfs_fscache_invalidate_page(page, page->mapping->host);
}
+/*
+ * Attempt to release the private state associated with a page
+ * - Called if either PG_private or PG_fscache is set on the page
+ * - Caller holds page lock
+ * - Return true (may release page) or false (may not)
+ */
static int nfs_release_page(struct page *page, gfp_t gfp)
{
dfprintk(PAGECACHE, "NFS: release_page(%p)\n", page);
/* If PagePrivate() is set, then the page is not freeable */
- return 0;
+ if (PagePrivate(page))
+ return 0;
+ return nfs_fscache_release_page(page, gfp);
}
+/*
+ * Attempt to clear the private state associated with a page when an error
+ * occurs that requires the cached contents of an inode to be written back or
+ * destroyed
+ * - Called if either PG_private or fscache is set on the page
+ * - Caller holds page lock
+ * - Return 0 if successful, -error otherwise
+ */
static int nfs_launder_page(struct page *page)
{
struct inode *inode = page->mapping->host;
+ struct nfs_inode *nfsi = NFS_I(inode);
dfprintk(PAGECACHE, "NFS: launder_page(%ld, %llu)\n",
inode->i_ino, (long long)page_offset(page));
+ nfs_fscache_wait_on_page_write(nfsi, page);
return nfs_wb_page(inode, page);
}
@@ -451,8 +479,14 @@ const struct address_space_operations nfs_file_aops = {
.launder_page = nfs_launder_page,
};
-static int nfs_vm_page_mkwrite(struct vm_area_struct *vma, struct page *page)
+/*
+ * Notification that a PTE pointing to an NFS page is about to be made
+ * writable, implying that someone is about to modify the page through a
+ * shared-writable mapping
+ */
+static int nfs_vm_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
{
+ struct page *page = vmf->page;
struct file *filp = vma->vm_file;
struct dentry *dentry = filp->f_path.dentry;
unsigned pagelen;
@@ -464,6 +498,9 @@ static int nfs_vm_page_mkwrite(struct vm_area_struct *vma, struct page *page)
filp->f_mapping->host->i_ino,
(long long)page_offset(page));
+ /* make sure the cache has finished storing the page */
+ nfs_fscache_wait_on_page_write(NFS_I(dentry->d_inode), page);
+
lock_page(page);
mapping = page->mapping;
if (mapping != dentry->d_inode->i_mapping)
@@ -483,6 +520,8 @@ static int nfs_vm_page_mkwrite(struct vm_area_struct *vma, struct page *page)
ret = pagelen;
out_unlock:
unlock_page(page);
+ if (ret)
+ ret = VM_FAULT_SIGBUS;
return ret;
}