/** * reiser4_attach_fsdata - try to attach fsdata * @file: * @inode: * * Finds or creates cursor for readdir-over-nfs. */ int reiser4_attach_fsdata(struct file *file, struct inode *inode) { loff_t pos; int result; dir_cursor *cursor; /* * we are serialized by inode->i_mutex */ if (!file_is_stateless(file)) return 0; pos = file->f_pos; result = 0; if (pos == 0) { /* * first call to readdir (or rewind to the beginning of * directory) */ cursor = kmem_cache_alloc(d_cursor_cache, reiser4_ctx_gfp_mask_get()); if (cursor != NULL) result = insert_cursor(cursor, file, inode); else result = RETERR(-ENOMEM); } else { /* try to find existing cursor */ struct d_cursor_key key; key.cid = pos >> CID_SHIFT; key.oid = get_inode_oid(inode); spin_lock(&d_lock); cursor = d_cursor_hash_find(&d_info(inode)->table, &key); if (cursor != NULL) { /* cursor was found */ if (cursor->ref == 0) { /* move it from unused list */ list_del_init(&cursor->alist); --d_cursor_unused; } ++cursor->ref; } spin_unlock(&d_lock); if (cursor != NULL) { spin_lock_inode(inode); assert("nikita-3556", cursor->fsdata->back == NULL); clean_fsdata(file); free_file_fsdata_nolock(file); file->private_data = cursor->fsdata; spin_unlock_inode(inode); } } return result; }
/* this is common implementation of key_by_inode method of file plugin */ int key_by_inode_and_offset_common(struct inode *inode, loff_t off, reiser4_key * key) { reiser4_key_init(key); set_key_locality(key, reiser4_inode_data(inode)->locality_id); set_key_ordering(key, get_inode_ordering(inode)); set_key_objectid(key, get_inode_oid(inode)); /*FIXME: inode->i_ino */ set_key_type(key, KEY_BODY_MINOR); set_key_offset(key, (__u64) off); return 0; }
/** * insert_cursor - allocate file_fsdata, insert cursor to tree and hash table * @cursor: * @file: * @inode: * * Allocates reiser4_file_fsdata, attaches it to @cursor, inserts cursor to * reiser4 super block's hash table and radix tree. add detachable readdir * state to the @f */ static int insert_cursor(dir_cursor *cursor, struct file *file, struct inode *inode) { int result; reiser4_file_fsdata *fsdata; memset(cursor, 0, sizeof *cursor); /* this is either first call to readdir, or rewind. Anyway, create new * cursor. */ fsdata = create_fsdata(NULL); if (fsdata != NULL) { result = radix_tree_preload(reiser4_ctx_gfp_mask_get()); if (result == 0) { struct d_cursor_info *info; oid_t oid; info = d_info(inode); oid = get_inode_oid(inode); /* cid occupies higher 12 bits of f->f_pos. Don't * allow it to become negative: this confuses * nfsd_readdir() */ cursor->key.cid = (++cid_counter) & 0x7ff; cursor->key.oid = oid; cursor->fsdata = fsdata; cursor->info = info; cursor->ref = 1; spin_lock_inode(inode); /* install cursor as @f's private_data, discarding old * one if necessary */ #if REISER4_DEBUG if (file->private_data) warning("", "file has fsdata already"); #endif clean_fsdata(file); free_file_fsdata_nolock(file); file->private_data = fsdata; fsdata->cursor = cursor; spin_unlock_inode(inode); spin_lock(&d_lock); /* insert cursor into hash table */ d_cursor_hash_insert(&info->table, cursor); /* and chain it into radix-tree */ bind_cursor(cursor, (unsigned long)oid); spin_unlock(&d_lock); radix_tree_preload_end(); file->f_pos = ((__u64) cursor->key.cid) << CID_SHIFT; } } else result = RETERR(-ENOMEM); return result; }
/* clear stat data's flag indicating that conversion is being converted */ static int complete_conversion(struct inode *inode) { int result; grab_space_enable(); result = reiser4_grab_space(inode_file_plugin(inode)->estimate.update(inode), BA_CAN_COMMIT); if (result == 0) { reiser4_inode_clr_flag(inode, REISER4_PART_MIXED); result = reiser4_update_sd(inode); } if (result) warning("vs-1696", "Failed to clear converting bit of %llu: %i", (unsigned long long)get_inode_oid(inode), result); return 0; }
/* this is common implementation of write_sd_by_inode method of file plugin either insert stat data or update it */ int write_sd_by_inode_common(struct inode *inode/* object to save */) { int result; assert("nikita-730", inode != NULL); if (reiser4_inode_get_flag(inode, REISER4_NO_SD)) /* object doesn't have stat-data yet */ result = insert_new_sd(inode); else result = update_sd(inode); if (result != 0 && result != -ENAMETOOLONG && result != -ENOMEM) /* Don't issue warnings about "name is too long" */ warning("nikita-2221", "Failed to save sd for %llu: %i", (unsigned long long)get_inode_oid(inode), result); return result; }
/* for every page of file: read page, cut part of extent pointing to this page, put data of page tree by tail item */ int extent2tail(struct file * file, struct unix_file_info *uf_info) { int result; struct inode *inode; struct page *page; unsigned long num_pages, i; unsigned long start_page; reiser4_key from; reiser4_key to; unsigned count; __u64 offset; assert("nikita-3362", ea_obtained(uf_info)); inode = unix_file_info_to_inode(uf_info); assert("nikita-3412", !IS_RDONLY(inode)); assert("vs-1649", uf_info->container != UF_CONTAINER_TAILS); assert("", !reiser4_inode_get_flag(inode, REISER4_PART_IN_CONV)); offset = 0; if (reiser4_inode_get_flag(inode, REISER4_PART_MIXED)) { /* * file is marked on disk as there was a conversion which did * not complete due to either crash or some error. Find which * offset tail conversion stopped at */ result = find_start(inode, EXTENT_POINTER_ID, &offset); if (result == -ENOENT) { /* no extent found, everything is converted */ uf_info->container = UF_CONTAINER_TAILS; complete_conversion(inode); return 0; } else if (result != 0) /* some other error */ return result; } reiser4_inode_set_flag(inode, REISER4_PART_IN_CONV); /* number of pages in the file */ num_pages = (inode->i_size + - offset + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; start_page = offset >> PAGE_CACHE_SHIFT; inode_file_plugin(inode)->key_by_inode(inode, offset, &from); to = from; result = 0; for (i = 0; i < num_pages; i++) { __u64 start_byte; result = reserve_extent2tail_iteration(inode); if (result != 0) break; if (i == 0 && offset == 0) { reiser4_inode_set_flag(inode, REISER4_PART_MIXED); reiser4_update_sd(inode); } page = read_mapping_page(inode->i_mapping, (unsigned)(i + start_page), NULL); if (IS_ERR(page)) { result = PTR_ERR(page); break; } wait_on_page_locked(page); if (!PageUptodate(page)) { page_cache_release(page); result = RETERR(-EIO); break; } /* cut part of file we have read */ start_byte = (__u64) ((i + start_page) << PAGE_CACHE_SHIFT); set_key_offset(&from, start_byte); set_key_offset(&to, start_byte + PAGE_CACHE_SIZE - 1); /* * reiser4_cut_tree_object() returns -E_REPEAT to allow atom * commits during over-long truncates. But * extent->tail conversion should be performed in one * transaction. */ result = reiser4_cut_tree(reiser4_tree_by_inode(inode), &from, &to, inode, 0); if (result) { page_cache_release(page); break; } /* put page data into tree via tail_write */ count = PAGE_CACHE_SIZE; if ((i == (num_pages - 1)) && (inode->i_size & ~PAGE_CACHE_MASK)) /* last page can be incompleted */ count = (inode->i_size & ~PAGE_CACHE_MASK); while (count) { loff_t pos = start_byte; assert("edward-1537", file != NULL && file->f_dentry != NULL); assert("edward-1538", file->f_dentry->d_inode == inode); result = reiser4_write_tail(file, inode, (char __user *)kmap(page), count, &pos); reiser4_free_file_fsdata(file); if (result <= 0) { warning("", "reiser4_write_tail failed"); page_cache_release(page); reiser4_inode_clr_flag(inode, REISER4_PART_IN_CONV); return result; } count -= result; } /* release page */ lock_page(page); /* page is already detached from jnode and mapping. */ assert("vs-1086", page->mapping == NULL); assert("nikita-2690", (!PagePrivate(page) && jprivate(page) == 0)); /* waiting for writeback completion with page lock held is * perfectly valid. */ wait_on_page_writeback(page); reiser4_drop_page(page); /* release reference taken by read_cache_page() above */ page_cache_release(page); drop_exclusive_access(uf_info); /* * throttle the conversion. * FIXME-EDWARD: Calculate and pass the precise number * of pages that was dirtied */ reiser4_throttle_write(inode, 1); get_exclusive_access(uf_info); /* * nobody is allowed to complete conversion but a process which * started it */ assert("", reiser4_inode_get_flag(inode, REISER4_PART_MIXED)); } reiser4_inode_clr_flag(inode, REISER4_PART_IN_CONV); if (i == num_pages) { /* file is converted to formatted items */ assert("vs-1698", reiser4_inode_get_flag(inode, REISER4_PART_MIXED)); assert("vs-1260", inode_has_no_jnodes(reiser4_inode_data(inode))); uf_info->container = UF_CONTAINER_TAILS; complete_conversion(inode); return 0; } /* * conversion is not complete. Inode was already marked as * REISER4_PART_MIXED and stat-data were updated at the first * iteration of the loop above. */ warning("nikita-2282", "Partial conversion of %llu: %lu of %lu: %i", (unsigned long long)get_inode_oid(inode), i, num_pages, result); /* this flag should be cleared, otherwise get_exclusive_access_careful() will fall into infinite loop */ assert("edward-1550", !reiser4_inode_get_flag(inode, REISER4_PART_IN_CONV)); return result; }
/** * tail2extent * @uf_info: * * */ int tail2extent(struct unix_file_info *uf_info) { int result; reiser4_key key; /* key of next byte to be moved to page */ char *p_data; /* data of page */ unsigned page_off = 0, /* offset within the page where to copy data */ count; /* number of bytes of item which can be * copied to page */ struct page *pages[TAIL2EXTENT_PAGE_NUM]; struct page *page; int done; /* set to 1 when all file is read */ char *item; int i; struct inode *inode; int first_iteration; int bytes; __u64 offset; assert("nikita-3362", ea_obtained(uf_info)); inode = unix_file_info_to_inode(uf_info); assert("nikita-3412", !IS_RDONLY(inode)); assert("vs-1649", uf_info->container != UF_CONTAINER_EXTENTS); assert("", !reiser4_inode_get_flag(inode, REISER4_PART_IN_CONV)); offset = 0; first_iteration = 1; result = 0; if (reiser4_inode_get_flag(inode, REISER4_PART_MIXED)) { /* * file is marked on disk as there was a conversion which did * not complete due to either crash or some error. Find which * offset tail conversion stopped at */ result = find_start(inode, FORMATTING_ID, &offset); if (result == -ENOENT) { /* no tail items found, everything is converted */ uf_info->container = UF_CONTAINER_EXTENTS; complete_conversion(inode); return 0; } else if (result != 0) /* some other error */ return result; first_iteration = 0; } reiser4_inode_set_flag(inode, REISER4_PART_IN_CONV); /* get key of first byte of a file */ inode_file_plugin(inode)->key_by_inode(inode, offset, &key); done = 0; while (done == 0) { memset(pages, 0, sizeof(pages)); result = reserve_tail2extent_iteration(inode); if (result != 0) { reiser4_inode_clr_flag(inode, REISER4_PART_IN_CONV); goto out; } if (first_iteration) { reiser4_inode_set_flag(inode, REISER4_PART_MIXED); reiser4_update_sd(inode); first_iteration = 0; } bytes = 0; for (i = 0; i < sizeof_array(pages) && done == 0; i++) { assert("vs-598", (get_key_offset(&key) & ~PAGE_CACHE_MASK) == 0); page = alloc_page(reiser4_ctx_gfp_mask_get()); if (!page) { result = RETERR(-ENOMEM); goto error; } page->index = (unsigned long)(get_key_offset(&key) >> PAGE_CACHE_SHIFT); /* * usually when one is going to longterm lock znode (as * find_file_item does, for instance) he must not hold * locked pages. However, there is an exception for * case tail2extent. Pages appearing here are not * reachable to everyone else, they are clean, they do * not have jnodes attached so keeping them locked do * not risk deadlock appearance */ assert("vs-983", !PagePrivate(page)); reiser4_invalidate_pages(inode->i_mapping, page->index, 1, 0); for (page_off = 0; page_off < PAGE_CACHE_SIZE;) { coord_t coord; lock_handle lh; /* get next item */ /* FIXME: we might want to readahead here */ init_lh(&lh); result = find_file_item_nohint(&coord, &lh, &key, ZNODE_READ_LOCK, inode); if (result != CBK_COORD_FOUND) { /* * error happened of not items of file * were found */ done_lh(&lh); page_cache_release(page); goto error; } if (coord.between == AFTER_UNIT) { /* * end of file is reached. Padd page * with zeros */ done_lh(&lh); done = 1; p_data = kmap_atomic(page, KM_USER0); memset(p_data + page_off, 0, PAGE_CACHE_SIZE - page_off); kunmap_atomic(p_data, KM_USER0); break; } result = zload(coord.node); if (result) { page_cache_release(page); done_lh(&lh); goto error; } assert("vs-856", coord.between == AT_UNIT); item = ((char *)item_body_by_coord(&coord)) + coord.unit_pos; /* how many bytes to copy */ count = item_length_by_coord(&coord) - coord.unit_pos; /* limit length of copy to end of page */ if (count > PAGE_CACHE_SIZE - page_off) count = PAGE_CACHE_SIZE - page_off; /* * copy item (as much as will fit starting from * the beginning of the item) into the page */ p_data = kmap_atomic(page, KM_USER0); memcpy(p_data + page_off, item, count); kunmap_atomic(p_data, KM_USER0); page_off += count; bytes += count; set_key_offset(&key, get_key_offset(&key) + count); zrelse(coord.node); done_lh(&lh); } /* end of loop which fills one page by content of * formatting items */ if (page_off) { /* something was copied into page */ pages[i] = page; } else { page_cache_release(page); assert("vs-1648", done == 1); break; } } /* end of loop through pages of one conversion iteration */ if (i > 0) { result = replace(inode, pages, i, bytes); release_all_pages(pages, sizeof_array(pages)); if (result) goto error; /* * We have to drop exclusive access to avoid deadlock * which may happen because called by reiser4_writepages * capture_unix_file requires to get non-exclusive * access to a file. It is safe to drop EA in the middle * of tail2extent conversion because write_unix_file, * setattr_unix_file(truncate), mmap_unix_file, * release_unix_file(extent2tail) checks if conversion * is not in progress (see comments before * get_exclusive_access_careful(). * Other processes that acquire non-exclusive access * (read_unix_file, reiser4_writepages, etc) should work * on partially converted files. */ drop_exclusive_access(uf_info); /* throttle the conversion FIXME-EDWARD: Pass the precise number of pages that was dirtied */ reiser4_throttle_write(inode, 1); get_exclusive_access(uf_info); /* * nobody is allowed to complete conversion but a * process which started it */ assert("", reiser4_inode_get_flag(inode, REISER4_PART_MIXED)); } } if (result == 0) { /* file is converted to extent items */ reiser4_inode_clr_flag(inode, REISER4_PART_IN_CONV); assert("vs-1697", reiser4_inode_get_flag(inode, REISER4_PART_MIXED)); uf_info->container = UF_CONTAINER_EXTENTS; complete_conversion(inode); } else { /* * conversion is not complete. Inode was already marked as * REISER4_PART_MIXED and stat-data were updated at the first * iteration of the loop above. */ error: release_all_pages(pages, sizeof_array(pages)); reiser4_inode_clr_flag(inode, REISER4_PART_IN_CONV); warning("edward-1548", "Partial conversion of %llu: %i", (unsigned long long)get_inode_oid(inode), result); } out: /* this flag should be cleared, otherwise get_exclusive_access_careful() will fall into infinite loop */ assert("edward-1549", !reiser4_inode_get_flag(inode, REISER4_PART_IN_CONV)); return result; }
/** * process_cursors - do action on each cursor attached to inode * @inode: * @act: action to do * * Finds all cursors of @inode in reiser4's super block radix tree of cursors * and performs action specified by @act on each of cursors. */ static void process_cursors(struct inode *inode, enum cursor_action act) { oid_t oid; dir_cursor *start; struct list_head *head; reiser4_context *ctx; struct d_cursor_info *info; /* this can be called by * * kswapd->...->prune_icache->..reiser4_destroy_inode * * without reiser4_context */ ctx = reiser4_init_context(inode->i_sb); if (IS_ERR(ctx)) { warning("vs-23", "failed to init context"); return; } assert("nikita-3558", inode != NULL); info = d_info(inode); oid = get_inode_oid(inode); spin_lock_inode(inode); head = get_readdir_list(inode); spin_lock(&d_lock); /* find any cursor for this oid: reference to it is hanging of radix * tree */ start = lookup(info, (unsigned long)oid); if (start != NULL) { dir_cursor *scan; reiser4_file_fsdata *fsdata; /* process circular list of cursors for this oid */ scan = start; do { dir_cursor *next; next = list_entry(scan->list.next, dir_cursor, list); fsdata = scan->fsdata; assert("nikita-3557", fsdata != NULL); if (scan->key.oid == oid) { switch (act) { case CURSOR_DISPOSE: list_del_init(&fsdata->dir.linkage); break; case CURSOR_LOAD: list_add(&fsdata->dir.linkage, head); break; case CURSOR_KILL: kill_cursor(scan); break; } } if (scan == next) /* last cursor was just killed */ break; scan = next; } while (scan != start); } spin_unlock(&d_lock); /* check that we killed 'em all */ assert("nikita-3568", ergo(act == CURSOR_KILL, list_empty_careful(get_readdir_list(inode)))); assert("nikita-3569", ergo(act == CURSOR_KILL, lookup(info, oid) == NULL)); spin_unlock_inode(inode); reiser4_exit_context(ctx); }