diff options
Diffstat (limited to 'fs/nfs/dir.c')
-rw-r--r-- | fs/nfs/dir.c | 90 |
1 files changed, 49 insertions, 41 deletions
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c index 1e5321d1ed22..2517fcd423b6 100644 --- a/fs/nfs/dir.c +++ b/fs/nfs/dir.c @@ -57,7 +57,7 @@ static void nfs_readdir_clear_array(struct page*); const struct file_operations nfs_dir_operations = { .llseek = nfs_llseek_dir, .read = generic_read_dir, - .iterate_shared = nfs_readdir, + .iterate = nfs_readdir, .open = nfs_opendir, .release = nfs_closedir, .fsync = nfs_fsync_dir, @@ -145,7 +145,6 @@ struct nfs_cache_array_entry { }; struct nfs_cache_array { - atomic_t refcount; int size; int eof_index; u64 last_cookie; @@ -170,6 +169,17 @@ typedef struct { unsigned int eof:1; } nfs_readdir_descriptor_t; +static +void nfs_readdir_init_array(struct page *page) +{ + struct nfs_cache_array *array; + + array = kmap_atomic(page); + memset(array, 0, sizeof(struct nfs_cache_array)); + array->eof_index = -1; + kunmap_atomic(array); +} + /* * The caller is responsible for calling nfs_readdir_release_array(page) */ @@ -201,18 +211,10 @@ void nfs_readdir_clear_array(struct page *page) int i; array = kmap_atomic(page); - if (atomic_dec_and_test(&array->refcount)) - for (i = 0; i < array->size; i++) - kfree(array->array[i].string.name); - kunmap_atomic(array); -} - -static bool grab_page(struct page *page) -{ - struct nfs_cache_array *array = kmap_atomic(page); - bool res = atomic_inc_not_zero(&array->refcount); + for (i = 0; i < array->size; i++) + kfree(array->array[i].string.name); + array->size = 0; kunmap_atomic(array); - return res; } /* @@ -287,7 +289,7 @@ int nfs_readdir_search_for_pos(struct nfs_cache_array *array, nfs_readdir_descri desc->cache_entry_index = index; return 0; out_eof: - desc->eof = 1; + desc->eof = true; return -EBADCOOKIE; } @@ -341,7 +343,7 @@ int nfs_readdir_search_for_cookie(struct nfs_cache_array *array, nfs_readdir_des if (array->eof_index >= 0) { status = -EBADCOOKIE; if (*desc->dir_cookie == array->last_cookie) - desc->eof = 1; + desc->eof = true; } out: return status; @@ -653,6 +655,8 @@ int nfs_readdir_xdr_to_array(nfs_readdir_descriptor_t *desc, struct page *page, int status = -ENOMEM; unsigned int array_size = ARRAY_SIZE(pages); + nfs_readdir_init_array(page); + entry.prev_cookie = 0; entry.cookie = desc->last_cookie; entry.eof = 0; @@ -673,9 +677,6 @@ int nfs_readdir_xdr_to_array(nfs_readdir_descriptor_t *desc, struct page *page, status = PTR_ERR(array); goto out_label_free; } - memset(array, 0, sizeof(struct nfs_cache_array)); - atomic_set(&array->refcount, 1); - array->eof_index = -1; status = nfs_readdir_alloc_pages(pages, array_size); if (status < 0) @@ -730,6 +731,7 @@ int nfs_readdir_filler(nfs_readdir_descriptor_t *desc, struct page* page) unlock_page(page); return 0; error: + nfs_readdir_clear_array(page); unlock_page(page); return ret; } @@ -737,7 +739,6 @@ int nfs_readdir_filler(nfs_readdir_descriptor_t *desc, struct page* page) static void cache_page_release(nfs_readdir_descriptor_t *desc) { - nfs_readdir_clear_array(desc->page); put_page(desc->page); desc->page = NULL; } @@ -745,33 +746,34 @@ void cache_page_release(nfs_readdir_descriptor_t *desc) static struct page *get_cache_page(nfs_readdir_descriptor_t *desc) { - struct page *page; - - for (;;) { - page = read_cache_page(desc->file->f_mapping, + return read_cache_page(desc->file->f_mapping, desc->page_index, (filler_t *)nfs_readdir_filler, desc); - if (IS_ERR(page) || grab_page(page)) - break; - put_page(page); - } - return page; } /* * Returns 0 if desc->dir_cookie was found on page desc->page_index + * and locks the page to prevent removal from the page cache. */ static -int find_cache_page(nfs_readdir_descriptor_t *desc) +int find_and_lock_cache_page(nfs_readdir_descriptor_t *desc) { int res; desc->page = get_cache_page(desc); if (IS_ERR(desc->page)) return PTR_ERR(desc->page); - - res = nfs_readdir_search_array(desc); + res = lock_page_killable(desc->page); if (res != 0) - cache_page_release(desc); + goto error; + res = -EAGAIN; + if (desc->page->mapping != NULL) { + res = nfs_readdir_search_array(desc); + if (res == 0) + return 0; + } + unlock_page(desc->page); +error: + cache_page_release(desc); return res; } @@ -786,7 +788,7 @@ int readdir_search_pagecache(nfs_readdir_descriptor_t *desc) desc->last_cookie = 0; } do { - res = find_cache_page(desc); + res = find_and_lock_cache_page(desc); } while (res == -EAGAIN); return res; } @@ -815,7 +817,7 @@ int nfs_do_filldir(nfs_readdir_descriptor_t *desc) ent = &array->array[i]; if (!dir_emit(desc->ctx, ent->string.name, ent->string.len, nfs_compat_user_ino64(ent->ino), ent->d_type)) { - desc->eof = 1; + desc->eof = true; break; } desc->ctx->pos++; @@ -827,11 +829,10 @@ int nfs_do_filldir(nfs_readdir_descriptor_t *desc) ctx->duped = 1; } if (array->eof_index >= 0) - desc->eof = 1; + desc->eof = true; nfs_readdir_release_array(desc->page); out: - cache_page_release(desc); dfprintk(DIRCACHE, "NFS: nfs_do_filldir() filling ended @ cookie %Lu; returning = %d\n", (unsigned long long)*desc->dir_cookie, res); return res; @@ -877,13 +878,13 @@ int uncached_readdir(nfs_readdir_descriptor_t *desc) status = nfs_do_filldir(desc); + out_release: + nfs_readdir_clear_array(desc->page); + cache_page_release(desc); out: dfprintk(DIRCACHE, "NFS: %s: returns %d\n", __func__, status); return status; - out_release: - cache_page_release(desc); - goto out; } /* The file offset position represents the dirent entry number. A @@ -928,7 +929,7 @@ static int nfs_readdir(struct file *file, struct dir_context *ctx) if (res == -EBADCOOKIE) { res = 0; /* This means either end of directory */ - if (*desc->dir_cookie && desc->eof == 0) { + if (*desc->dir_cookie && !desc->eof) { /* Or that the server has 'lost' a cookie */ res = uncached_readdir(desc); if (res == 0) @@ -948,6 +949,8 @@ static int nfs_readdir(struct file *file, struct dir_context *ctx) break; res = nfs_do_filldir(desc); + unlock_page(desc->page); + cache_page_release(desc); if (res < 0) break; } while (!desc->eof); @@ -960,11 +963,13 @@ out: static loff_t nfs_llseek_dir(struct file *filp, loff_t offset, int whence) { + struct inode *inode = file_inode(filp); struct nfs_open_dir_context *dir_ctx = filp->private_data; dfprintk(FILE, "NFS: llseek dir(%pD2, %lld, %d)\n", filp, offset, whence); + inode_lock(inode); switch (whence) { case 1: offset += filp->f_pos; @@ -972,13 +977,16 @@ static loff_t nfs_llseek_dir(struct file *filp, loff_t offset, int whence) if (offset >= 0) break; default: - return -EINVAL; + offset = -EINVAL; + goto out; } if (offset != filp->f_pos) { filp->f_pos = offset; dir_ctx->dir_cookie = 0; dir_ctx->duped = 0; } +out: + inode_unlock(inode); return offset; } |