#include "linux_err.h"
#include "bitops.h"
#include "kmem.h"
+#include "crc32.h"
#include "ubifs.h"
#include "defs.h"
#include "debug.h"
dbg_fsck("file %lu is reachable, in %s", file->inum, c->dev_name);
return true;
}
+
+/**
+ * calculate_file_info - calculate the information of file
+ * @c: UBIFS file-system description object
+ * @file: file object
+ * @file_tree: tree of all scanned files
+ *
+ * This function calculates file information according to dentry nodes,
+ * data nodes and truncation node. The calculated informaion will be used
+ * to correct inode node.
+ */
+static void calculate_file_info(struct ubifs_info *c, struct scanned_file *file,
+ struct rb_root *file_tree)
+{
+ int nlink = 0;
+ bool corrupted_truncation = false;
+ unsigned long long ino_sqnum, trun_size = 0, new_size = 0, trun_sqnum = 0;
+ struct rb_node *node;
+ struct scanned_file *parent_file, *xattr_file;
+ struct scanned_dent_node *dent_node;
+ struct scanned_data_node *data_node;
+ LIST_HEAD(drop_list);
+
+ for (node = rb_first(&file->xattr_files); node; node = rb_next(node)) {
+ xattr_file = rb_entry(node, struct scanned_file, rb);
+
+ ubifs_assert(c, !rb_first(&xattr_file->xattr_files));
+ calculate_file_info(c, xattr_file, file_tree);
+ }
+
+ if (file->inum == UBIFS_ROOT_INO) {
+ file->calc_nlink += 2;
+ file->calc_size += UBIFS_INO_NODE_SZ;
+ return;
+ }
+
+ if (S_ISDIR(file->ino.mode)) {
+ file->calc_nlink += 2;
+ file->calc_size += UBIFS_INO_NODE_SZ;
+
+ dent_node = rb_entry(rb_first(&file->dent_nodes),
+ struct scanned_dent_node, rb);
+ parent_file = lookup_file(file_tree, key_inum(c, &dent_node->key));
+ if (!parent_file) {
+ ubifs_assert(c, 0);
+ return;
+ }
+ parent_file->calc_nlink += 1;
+ parent_file->calc_size += CALC_DENT_SIZE(dent_node->nlen);
+ return;
+ }
+
+ if (file->ino.is_xattr) {
+ file->calc_nlink = 1;
+ file->calc_size = file->ino.size;
+
+ dent_node = rb_entry(rb_first(&file->dent_nodes),
+ struct scanned_dent_node, rb);
+ parent_file = lookup_file(file_tree, key_inum(c, &dent_node->key));
+ if (!parent_file) {
+ ubifs_assert(c, 0);
+ return;
+ }
+ parent_file->calc_xcnt += 1;
+ parent_file->calc_xsz += CALC_DENT_SIZE(dent_node->nlen);
+ parent_file->calc_xsz += CALC_XATTR_BYTES(file->ino.size);
+ parent_file->calc_xnms += dent_node->nlen;
+ return;
+ }
+
+ for (node = rb_first(&file->dent_nodes); node; node = rb_next(node)) {
+ nlink++;
+
+ dent_node = rb_entry(node, struct scanned_dent_node, rb);
+
+ parent_file = lookup_file(file_tree, key_inum(c, &dent_node->key));
+ if (!parent_file) {
+ ubifs_assert(c, 0);
+ return;
+ }
+ parent_file->calc_size += CALC_DENT_SIZE(dent_node->nlen);
+ }
+ file->calc_nlink = nlink;
+
+ if (!S_ISREG(file->ino.mode)) {
+ /* No need to verify i_size for symlink/sock/block/char/fifo. */
+ file->calc_size = file->ino.size;
+ return;
+ }
+
+ /*
+ * Process i_size and data content, following situations should
+ * be considered:
+ * 1. Sequential writing or overwriting, i_size should be
+ * max(i_size, data node size), pick larger sqnum one from
+ * data nodes with same block index.
+ * 2. Mixed truncation and writing, i_size depends on the latest
+ * truncation node or inode node or last data node, pick data
+ * nodes which are not truncated.
+ * 3. Setting bigger i_size attr, pick inode size or biggest
+ * i_size calculated by data nodes.
+ */
+ if (file->trun.header.exist) {
+ trun_size = file->trun.new_size;
+ trun_sqnum = file->trun.header.sqnum;
+ }
+ ino_sqnum = file->ino.header.sqnum;
+ for (node = rb_first(&file->data_nodes); node; node = rb_next(node)) {
+ unsigned long long d_sz, d_sqnum;
+ unsigned int block_no;
+
+ data_node = rb_entry(node, struct scanned_data_node, rb);
+
+ d_sqnum = data_node->header.sqnum;
+ block_no = key_block(c, &data_node->key);
+ d_sz = data_node->size + block_no * UBIFS_BLOCK_SIZE;
+ if ((trun_sqnum > d_sqnum && trun_size < d_sz) ||
+ (ino_sqnum > d_sqnum && file->ino.size < d_sz)) {
+ /*
+ * The truncated data nodes are not gced after
+ * truncating, just remove them.
+ */
+ list_add(&data_node->list, &drop_list);
+ } else {
+ new_size = max_t(unsigned long long, new_size, d_sz);
+ }
+ }
+ /*
+ * Truncation node is written successful, but inode node is not. It
+ * won't happen because inode node is written before truncation node
+ * according to ubifs_jnl_truncate(), unless only inode is corrupted.
+ * In this case, data nodes could have been removed in history mounting
+ * recovery, so i_size needs to be updated.
+ */
+ if (trun_sqnum > ino_sqnum && trun_size < file->ino.size) {
+ if (trun_size < new_size) {
+ corrupted_truncation = true;
+ /*
+ * Appendant writing after truncation and newest inode
+ * is not fell on disk.
+ */
+ goto update_isize;
+ }
+
+ /*
+ * Overwriting happens after truncation and newest inode is
+ * not fell on disk.
+ */
+ file->calc_size = trun_size;
+ goto drop_data;
+ }
+update_isize:
+ /*
+ * The file cannot use 'new_size' directly when the file may have ever
+ * been set i_size. For example:
+ * 1. echo 123 > file # i_size = 4
+ * 2. truncate -s 100 file # i_size = 100
+ * After scanning, new_size is 4. Apperantly the size of 'file' should
+ * be 100. So, the calculated new_size according to data nodes should
+ * only be used for extending i_size, like ubifs_recover_size() does.
+ */
+ if (new_size > file->ino.size || corrupted_truncation)
+ file->calc_size = new_size;
+ else
+ file->calc_size = file->ino.size;
+
+drop_data:
+ while (!list_empty(&drop_list)) {
+ data_node = list_entry(drop_list.next, struct scanned_data_node,
+ list);
+
+ list_del(&data_node->list);
+ rb_erase(&data_node->rb, &file->data_nodes);
+ kfree(data_node);
+ }
+}
+
+/**
+ * correct_file_info - correct the information of file
+ * @c: UBIFS file-system description object
+ * @file: file object
+ *
+ * This function corrects file information according to calculated fields,
+ * eg. 'calc_nlink', 'calc_xcnt', 'calc_xsz', 'calc_xnms' and 'calc_size'.
+ * Corrected inode node will be re-written.
+ */
+static int correct_file_info(struct ubifs_info *c, struct scanned_file *file)
+{
+ uint32_t crc;
+ int err, lnum, len;
+ struct rb_node *node;
+ struct ubifs_ino_node *ino;
+ struct scanned_file *xattr_file;
+
+ for (node = rb_first(&file->xattr_files); node; node = rb_next(node)) {
+ xattr_file = rb_entry(node, struct scanned_file, rb);
+
+ err = correct_file_info(c, xattr_file);
+ if (err)
+ return err;
+ }
+
+ if (file->calc_nlink == file->ino.nlink &&
+ file->calc_xcnt == file->ino.xcnt &&
+ file->calc_xsz == file->ino.xsz &&
+ file->calc_xnms == file->ino.xnms &&
+ file->calc_size == file->ino.size)
+ return 0;
+
+ lnum = file->ino.header.lnum;
+ dbg_fsck("correct file(inum:%lu type:%s), nlink %u->%u, xattr cnt %u->%u, xattr size %u->%u, xattr names %u->%u, size %llu->%llu, at %d:%d, in %s",
+ file->inum, file->ino.is_xattr ? "xattr" :
+ ubifs_get_type_name(ubifs_get_dent_type(file->ino.mode)),
+ file->ino.nlink, file->calc_nlink,
+ file->ino.xcnt, file->calc_xcnt,
+ file->ino.xsz, file->calc_xsz,
+ file->ino.xnms, file->calc_xnms,
+ file->ino.size, file->calc_size,
+ lnum, file->ino.header.offs, c->dev_name);
+
+ err = ubifs_leb_read(c, lnum, c->sbuf, 0, c->leb_size, 0);
+ if (err && err != -EBADMSG)
+ return err;
+
+ ino = c->sbuf + file->ino.header.offs;
+ ino->nlink = cpu_to_le32(file->calc_nlink);
+ ino->xattr_cnt = cpu_to_le32(file->calc_xcnt);
+ ino->xattr_size = cpu_to_le32(file->calc_xsz);
+ ino->xattr_names = cpu_to_le32(file->calc_xnms);
+ ino->size = cpu_to_le64(file->calc_size);
+ len = le32_to_cpu(ino->ch.len);
+ crc = crc32(UBIFS_CRC32_INIT, (void *)ino + 8, len - 8);
+ ino->ch.crc = cpu_to_le32(crc);
+
+ /* Atomically write the fixed LEB back again */
+ return ubifs_leb_change(c, lnum, c->sbuf, c->leb_size);
+}
+
+/**
+ * check_and_correct_files - check and correct information of files.
+ * @c: UBIFS file-system description object
+ *
+ * This function does similar things with dbg_check_filesystem(), besides,
+ * it also corrects file information if the calculated information is not
+ * consistent with information from flash.
+ */
+int check_and_correct_files(struct ubifs_info *c)
+{
+ int err;
+ struct rb_node *node;
+ struct scanned_file *file;
+ struct rb_root *tree = &FSCK(c)->rebuild->scanned_files;
+
+ for (node = rb_first(tree); node; node = rb_next(node)) {
+ file = rb_entry(node, struct scanned_file, rb);
+
+ calculate_file_info(c, file, tree);
+ }
+
+ for (node = rb_first(tree); node; node = rb_next(node)) {
+ file = rb_entry(node, struct scanned_file, rb);
+
+ err = correct_file_info(c, file);
+ if (err)
+ return err;
+ }
+
+ return 0;
+}
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