diff options
Diffstat (limited to 'fs/nfs/file.c')
| -rw-r--r-- | fs/nfs/file.c | 79 |
1 files changed, 58 insertions, 21 deletions
diff --git a/fs/nfs/file.c b/fs/nfs/file.c index 90f292b520d2..ec7e27d00bc6 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) @@ -479,11 +516,11 @@ static int nfs_vm_page_mkwrite(struct vm_area_struct *vma, struct page *page) goto out_unlock; ret = nfs_updatepage(filp, page, 0, pagelen); - if (ret == 0) - ret = pagelen; out_unlock: + if (!ret) + return VM_FAULT_LOCKED; unlock_page(page); - return ret; + return VM_FAULT_SIGBUS; } static struct vm_operations_struct nfs_file_vm_ops = { |