| /* |
| * JFFS2 -- Journalling Flash File System, Version 2. |
| * |
| * Copyright (C) 2001-2003 Red Hat, Inc. |
| * |
| * Created by David Woodhouse <dwmw2@infradead.org> |
| * |
| * For licensing information, see the file 'LICENCE' in this directory. |
| * |
| * $Id: readinode.c,v 1.143 2005/11/07 11:14:41 gleixner Exp $ |
| * |
| */ |
| |
| #include <linux/kernel.h> |
| #include <linux/sched.h> |
| #include <linux/slab.h> |
| #include <linux/fs.h> |
| #include <linux/crc32.h> |
| #include <linux/pagemap.h> |
| #include <linux/mtd/mtd.h> |
| #include <linux/compiler.h> |
| #include "nodelist.h" |
| |
| /* |
| * Put a new tmp_dnode_info into the temporaty RB-tree, keeping the list in |
| * order of increasing version. |
| */ |
| static void jffs2_add_tn_to_tree(struct jffs2_tmp_dnode_info *tn, struct rb_root *list) |
| { |
| struct rb_node **p = &list->rb_node; |
| struct rb_node * parent = NULL; |
| struct jffs2_tmp_dnode_info *this; |
| |
| while (*p) { |
| parent = *p; |
| this = rb_entry(parent, struct jffs2_tmp_dnode_info, rb); |
| |
| /* There may actually be a collision here, but it doesn't |
| actually matter. As long as the two nodes with the same |
| version are together, it's all fine. */ |
| if (tn->version > this->version) |
| p = &(*p)->rb_left; |
| else |
| p = &(*p)->rb_right; |
| } |
| |
| rb_link_node(&tn->rb, parent, p); |
| rb_insert_color(&tn->rb, list); |
| } |
| |
| static void jffs2_free_tmp_dnode_info_list(struct rb_root *list) |
| { |
| struct rb_node *this; |
| struct jffs2_tmp_dnode_info *tn; |
| |
| this = list->rb_node; |
| |
| /* Now at bottom of tree */ |
| while (this) { |
| if (this->rb_left) |
| this = this->rb_left; |
| else if (this->rb_right) |
| this = this->rb_right; |
| else { |
| tn = rb_entry(this, struct jffs2_tmp_dnode_info, rb); |
| jffs2_free_full_dnode(tn->fn); |
| jffs2_free_tmp_dnode_info(tn); |
| |
| this = this->rb_parent; |
| if (!this) |
| break; |
| |
| if (this->rb_left == &tn->rb) |
| this->rb_left = NULL; |
| else if (this->rb_right == &tn->rb) |
| this->rb_right = NULL; |
| else BUG(); |
| } |
| } |
| list->rb_node = NULL; |
| } |
| |
| static void jffs2_free_full_dirent_list(struct jffs2_full_dirent *fd) |
| { |
| struct jffs2_full_dirent *next; |
| |
| while (fd) { |
| next = fd->next; |
| jffs2_free_full_dirent(fd); |
| fd = next; |
| } |
| } |
| |
| /* Returns first valid node after 'ref'. May return 'ref' */ |
| static struct jffs2_raw_node_ref *jffs2_first_valid_node(struct jffs2_raw_node_ref *ref) |
| { |
| while (ref && ref->next_in_ino) { |
| if (!ref_obsolete(ref)) |
| return ref; |
| dbg_noderef("node at 0x%08x is obsoleted. Ignoring.\n", ref_offset(ref)); |
| ref = ref->next_in_ino; |
| } |
| return NULL; |
| } |
| |
| /* |
| * Helper function for jffs2_get_inode_nodes(). |
| * It is called every time an directory entry node is found. |
| * |
| * Returns: 0 on succes; |
| * 1 if the node should be marked obsolete; |
| * negative error code on failure. |
| */ |
| static inline int read_direntry(struct jffs2_sb_info *c, struct jffs2_raw_node_ref *ref, |
| struct jffs2_raw_dirent *rd, uint32_t read, struct jffs2_full_dirent **fdp, |
| uint32_t *latest_mctime, uint32_t *mctime_ver) |
| { |
| struct jffs2_full_dirent *fd; |
| |
| /* The direntry nodes are checked during the flash scanning */ |
| BUG_ON(ref_flags(ref) == REF_UNCHECKED); |
| /* Obsoleted. This cannot happen, surely? dwmw2 20020308 */ |
| BUG_ON(ref_obsolete(ref)); |
| |
| /* Sanity check */ |
| if (unlikely(PAD((rd->nsize + sizeof(*rd))) != PAD(je32_to_cpu(rd->totlen)))) { |
| JFFS2_ERROR("illegal nsize in node at %#08x: nsize %#02x, totlen %#04x\n", |
| ref_offset(ref), rd->nsize, je32_to_cpu(rd->totlen)); |
| return 1; |
| } |
| |
| fd = jffs2_alloc_full_dirent(rd->nsize + 1); |
| if (unlikely(!fd)) |
| return -ENOMEM; |
| |
| fd->raw = ref; |
| fd->version = je32_to_cpu(rd->version); |
| fd->ino = je32_to_cpu(rd->ino); |
| fd->type = rd->type; |
| |
| /* Pick out the mctime of the latest dirent */ |
| if(fd->version > *mctime_ver && je32_to_cpu(rd->mctime)) { |
| *mctime_ver = fd->version; |
| *latest_mctime = je32_to_cpu(rd->mctime); |
| } |
| |
| /* |
| * Copy as much of the name as possible from the raw |
| * dirent we've already read from the flash. |
| */ |
| if (read > sizeof(*rd)) |
| memcpy(&fd->name[0], &rd->name[0], |
| min_t(uint32_t, rd->nsize, (read - sizeof(*rd)) )); |
| |
| /* Do we need to copy any more of the name directly from the flash? */ |
| if (rd->nsize + sizeof(*rd) > read) { |
| /* FIXME: point() */ |
| int err; |
| int already = read - sizeof(*rd); |
| |
| err = jffs2_flash_read(c, (ref_offset(ref)) + read, |
| rd->nsize - already, &read, &fd->name[already]); |
| if (unlikely(read != rd->nsize - already) && likely(!err)) |
| return -EIO; |
| |
| if (unlikely(err)) { |
| JFFS2_ERROR("read remainder of name: error %d\n", err); |
| jffs2_free_full_dirent(fd); |
| return -EIO; |
| } |
| } |
| |
| fd->nhash = full_name_hash(fd->name, rd->nsize); |
| fd->next = NULL; |
| fd->name[rd->nsize] = '\0'; |
| |
| /* |
| * Wheee. We now have a complete jffs2_full_dirent structure, with |
| * the name in it and everything. Link it into the list |
| */ |
| jffs2_add_fd_to_list(c, fd, fdp); |
| |
| return 0; |
| } |
| |
| /* |
| * Helper function for jffs2_get_inode_nodes(). |
| * It is called every time an inode node is found. |
| * |
| * Returns: 0 on succes; |
| * 1 if the node should be marked obsolete; |
| * negative error code on failure. |
| */ |
| static inline int read_dnode(struct jffs2_sb_info *c, struct jffs2_raw_node_ref *ref, |
| struct jffs2_raw_inode *rd, struct rb_root *tnp, int rdlen, |
| uint32_t *latest_mctime, uint32_t *mctime_ver) |
| { |
| struct jffs2_tmp_dnode_info *tn; |
| uint32_t len, csize; |
| int ret = 1; |
| |
| /* Obsoleted. This cannot happen, surely? dwmw2 20020308 */ |
| BUG_ON(ref_obsolete(ref)); |
| |
| tn = jffs2_alloc_tmp_dnode_info(); |
| if (!tn) { |
| JFFS2_ERROR("failed to allocate tn (%d bytes).\n", sizeof(*tn)); |
| return -ENOMEM; |
| } |
| |
| tn->partial_crc = 0; |
| csize = je32_to_cpu(rd->csize); |
| |
| /* If we've never checked the CRCs on this node, check them now */ |
| if (ref_flags(ref) == REF_UNCHECKED) { |
| uint32_t crc; |
| |
| crc = crc32(0, rd, sizeof(*rd) - 8); |
| if (unlikely(crc != je32_to_cpu(rd->node_crc))) { |
| JFFS2_NOTICE("header CRC failed on node at %#08x: read %#08x, calculated %#08x\n", |
| ref_offset(ref), je32_to_cpu(rd->node_crc), crc); |
| goto free_out; |
| } |
| |
| /* Sanity checks */ |
| if (unlikely(je32_to_cpu(rd->offset) > je32_to_cpu(rd->isize)) || |
| unlikely(PAD(je32_to_cpu(rd->csize) + sizeof(*rd)) != PAD(je32_to_cpu(rd->totlen)))) { |
| JFFS2_WARNING("inode node header CRC is corrupted at %#08x\n", ref_offset(ref)); |
| jffs2_dbg_dump_node(c, ref_offset(ref)); |
| goto free_out; |
| } |
| |
| if (jffs2_is_writebuffered(c) && csize != 0) { |
| /* At this point we are supposed to check the data CRC |
| * of our unchecked node. But thus far, we do not |
| * know whether the node is valid or obsolete. To |
| * figure this out, we need to walk all the nodes of |
| * the inode and build the inode fragtree. We don't |
| * want to spend time checking data of nodes which may |
| * later be found to be obsolete. So we put off the full |
| * data CRC checking until we have read all the inode |
| * nodes and have started building the fragtree. |
| * |
| * The fragtree is being built starting with nodes |
| * having the highest version number, so we'll be able |
| * to detect whether a node is valid (i.e., it is not |
| * overlapped by a node with higher version) or not. |
| * And we'll be able to check only those nodes, which |
| * are not obsolete. |
| * |
| * Of course, this optimization only makes sense in case |
| * of NAND flashes (or other flashes whith |
| * !jffs2_can_mark_obsolete()), since on NOR flashes |
| * nodes are marked obsolete physically. |
| * |
| * Since NAND flashes (or other flashes with |
| * jffs2_is_writebuffered(c)) are anyway read by |
| * fractions of c->wbuf_pagesize, and we have just read |
| * the node header, it is likely that the starting part |
| * of the node data is also read when we read the |
| * header. So we don't mind to check the CRC of the |
| * starting part of the data of the node now, and check |
| * the second part later (in jffs2_check_node_data()). |
| * Of course, we will not need to re-read and re-check |
| * the NAND page which we have just read. This is why we |
| * read the whole NAND page at jffs2_get_inode_nodes(), |
| * while we needed only the node header. |
| */ |
| unsigned char *buf; |
| |
| /* 'buf' will point to the start of data */ |
| buf = (unsigned char *)rd + sizeof(*rd); |
| /* len will be the read data length */ |
| len = min_t(uint32_t, rdlen - sizeof(*rd), csize); |
| tn->partial_crc = crc32(0, buf, len); |
| |
| dbg_readinode("Calculates CRC (%#08x) for %d bytes, csize %d\n", tn->partial_crc, len, csize); |
| |
| /* If we actually calculated the whole data CRC |
| * and it is wrong, drop the node. */ |
| if (len >= csize && unlikely(tn->partial_crc != je32_to_cpu(rd->data_crc))) { |
| JFFS2_NOTICE("wrong data CRC in data node at 0x%08x: read %#08x, calculated %#08x.\n", |
| ref_offset(ref), tn->partial_crc, je32_to_cpu(rd->data_crc)); |
| goto free_out; |
| } |
| |
| } else if (csize == 0) { |
| /* |
| * We checked the header CRC. If the node has no data, adjust |
| * the space accounting now. For other nodes this will be done |
| * later either when the node is marked obsolete or when its |
| * data is checked. |
| */ |
| struct jffs2_eraseblock *jeb; |
| |
| dbg_readinode("the node has no data.\n"); |
| jeb = &c->blocks[ref->flash_offset / c->sector_size]; |
| len = ref_totlen(c, jeb, ref); |
| |
| spin_lock(&c->erase_completion_lock); |
| jeb->used_size += len; |
| jeb->unchecked_size -= len; |
| c->used_size += len; |
| c->unchecked_size -= len; |
| ref->flash_offset = ref_offset(ref) | REF_NORMAL; |
| spin_unlock(&c->erase_completion_lock); |
| } |
| } |
| |
| tn->fn = jffs2_alloc_full_dnode(); |
| if (!tn->fn) { |
| JFFS2_ERROR("alloc fn failed\n"); |
| ret = -ENOMEM; |
| goto free_out; |
| } |
| |
| tn->version = je32_to_cpu(rd->version); |
| tn->fn->ofs = je32_to_cpu(rd->offset); |
| tn->data_crc = je32_to_cpu(rd->data_crc); |
| tn->csize = csize; |
| tn->fn->raw = ref; |
| |
| /* There was a bug where we wrote hole nodes out with |
| csize/dsize swapped. Deal with it */ |
| if (rd->compr == JFFS2_COMPR_ZERO && !je32_to_cpu(rd->dsize) && csize) |
| tn->fn->size = csize; |
| else // normal case... |
| tn->fn->size = je32_to_cpu(rd->dsize); |
| |
| dbg_readinode("dnode @%08x: ver %u, offset %#04x, dsize %#04x, csize %#04x\n", |
| ref_offset(ref), je32_to_cpu(rd->version), je32_to_cpu(rd->offset), je32_to_cpu(rd->dsize), csize); |
| |
| jffs2_add_tn_to_tree(tn, tnp); |
| |
| return 0; |
| |
| free_out: |
| jffs2_free_tmp_dnode_info(tn); |
| return ret; |
| } |
| |
| /* |
| * Helper function for jffs2_get_inode_nodes(). |
| * It is called every time an unknown node is found. |
| * |
| * Returns: 0 on succes; |
| * 1 if the node should be marked obsolete; |
| * negative error code on failure. |
| */ |
| static inline int read_unknown(struct jffs2_sb_info *c, struct jffs2_raw_node_ref *ref, struct jffs2_unknown_node *un) |
| { |
| /* We don't mark unknown nodes as REF_UNCHECKED */ |
| BUG_ON(ref_flags(ref) == REF_UNCHECKED); |
| |
| un->nodetype = cpu_to_je16(JFFS2_NODE_ACCURATE | je16_to_cpu(un->nodetype)); |
| |
| if (crc32(0, un, sizeof(struct jffs2_unknown_node) - 4) != je32_to_cpu(un->hdr_crc)) { |
| /* Hmmm. This should have been caught at scan time. */ |
| JFFS2_NOTICE("node header CRC failed at %#08x. But it must have been OK earlier.\n", ref_offset(ref)); |
| jffs2_dbg_dump_node(c, ref_offset(ref)); |
| return 1; |
| } else { |
| switch(je16_to_cpu(un->nodetype) & JFFS2_COMPAT_MASK) { |
| |
| case JFFS2_FEATURE_INCOMPAT: |
| JFFS2_ERROR("unknown INCOMPAT nodetype %#04X at %#08x\n", |
| je16_to_cpu(un->nodetype), ref_offset(ref)); |
| /* EEP */ |
| BUG(); |
| break; |
| |
| case JFFS2_FEATURE_ROCOMPAT: |
| JFFS2_ERROR("unknown ROCOMPAT nodetype %#04X at %#08x\n", |
| je16_to_cpu(un->nodetype), ref_offset(ref)); |
| BUG_ON(!(c->flags & JFFS2_SB_FLAG_RO)); |
| break; |
| |
| case JFFS2_FEATURE_RWCOMPAT_COPY: |
| JFFS2_NOTICE("unknown RWCOMPAT_COPY nodetype %#04X at %#08x\n", |
| je16_to_cpu(un->nodetype), ref_offset(ref)); |
| break; |
| |
| case JFFS2_FEATURE_RWCOMPAT_DELETE: |
| JFFS2_NOTICE("unknown RWCOMPAT_DELETE nodetype %#04X at %#08x\n", |
| je16_to_cpu(un->nodetype), ref_offset(ref)); |
| return 1; |
| } |
| } |
| |
| return 0; |
| } |
| |
| /* |
| * Helper function for jffs2_get_inode_nodes(). |
| * The function detects whether more data should be read and reads it if yes. |
| * |
| * Returns: 0 on succes; |
| * negative error code on failure. |
| */ |
| static int read_more(struct jffs2_sb_info *c, struct jffs2_raw_node_ref *ref, |
| int right_size, int *rdlen, unsigned char *buf, unsigned char *bufstart) |
| { |
| int right_len, err, len; |
| size_t retlen; |
| uint32_t offs; |
| |
| if (jffs2_is_writebuffered(c)) { |
| right_len = c->wbuf_pagesize - (bufstart - buf); |
| if (right_size + (int)(bufstart - buf) > c->wbuf_pagesize) |
| right_len += c->wbuf_pagesize; |
| } else |
| right_len = right_size; |
| |
| if (*rdlen == right_len) |
| return 0; |
| |
| /* We need to read more data */ |
| offs = ref_offset(ref) + *rdlen; |
| if (jffs2_is_writebuffered(c)) { |
| bufstart = buf + c->wbuf_pagesize; |
| len = c->wbuf_pagesize; |
| } else { |
| bufstart = buf + *rdlen; |
| len = right_size - *rdlen; |
| } |
| |
| dbg_readinode("read more %d bytes\n", len); |
| |
| err = jffs2_flash_read(c, offs, len, &retlen, bufstart); |
| if (err) { |
| JFFS2_ERROR("can not read %d bytes from 0x%08x, " |
| "error code: %d.\n", len, offs, err); |
| return err; |
| } |
| |
| if (retlen < len) { |
| JFFS2_ERROR("short read at %#08x: %d instead of %d.\n", |
| offs, retlen, len); |
| return -EIO; |
| } |
| |
| *rdlen = right_len; |
| |
| return 0; |
| } |
| |
| /* Get tmp_dnode_info and full_dirent for all non-obsolete nodes associated |
| with this ino, returning the former in order of version */ |
| static int jffs2_get_inode_nodes(struct jffs2_sb_info *c, struct jffs2_inode_info *f, |
| struct rb_root *tnp, struct jffs2_full_dirent **fdp, |
| uint32_t *highest_version, uint32_t *latest_mctime, |
| uint32_t *mctime_ver) |
| { |
| struct jffs2_raw_node_ref *ref, *valid_ref; |
| struct rb_root ret_tn = RB_ROOT; |
| struct jffs2_full_dirent *ret_fd = NULL; |
| unsigned char *buf = NULL; |
| union jffs2_node_union *node; |
| size_t retlen; |
| int len, err; |
| |
| *mctime_ver = 0; |
| |
| dbg_readinode("ino #%u\n", f->inocache->ino); |
| |
| if (jffs2_is_writebuffered(c)) { |
| /* |
| * If we have the write buffer, we assume the minimal I/O unit |
| * is c->wbuf_pagesize. We implement some optimizations which in |
| * this case and we need a temporary buffer of size = |
| * 2*c->wbuf_pagesize bytes (see comments in read_dnode()). |
| * Basically, we want to read not only the node header, but the |
| * whole wbuf (NAND page in case of NAND) or 2, if the node |
| * header overlaps the border between the 2 wbufs. |
| */ |
| len = 2*c->wbuf_pagesize; |
| } else { |
| /* |
| * When there is no write buffer, the size of the temporary |
| * buffer is the size of the larges node header. |
| */ |
| len = sizeof(union jffs2_node_union); |
| } |
| |
| /* FIXME: in case of NOR and available ->point() this |
| * needs to be fixed. */ |
| buf = kmalloc(len, GFP_KERNEL); |
| if (!buf) |
| return -ENOMEM; |
| |
| spin_lock(&c->erase_completion_lock); |
| valid_ref = jffs2_first_valid_node(f->inocache->nodes); |
| if (!valid_ref && f->inocache->ino != 1) |
| JFFS2_WARNING("Eep. No valid nodes for ino #%u.\n", f->inocache->ino); |
| while (valid_ref) { |
| unsigned char *bufstart; |
| |
| /* We can hold a pointer to a non-obsolete node without the spinlock, |
| but _obsolete_ nodes may disappear at any time, if the block |
| they're in gets erased. So if we mark 'ref' obsolete while we're |
| not holding the lock, it can go away immediately. For that reason, |
| we find the next valid node first, before processing 'ref'. |
| */ |
| ref = valid_ref; |
| valid_ref = jffs2_first_valid_node(ref->next_in_ino); |
| spin_unlock(&c->erase_completion_lock); |
| |
| cond_resched(); |
| |
| /* |
| * At this point we don't know the type of the node we're going |
| * to read, so we do not know the size of its header. In order |
| * to minimize the amount of flash IO we assume the node has |
| * size = JFFS2_MIN_NODE_HEADER. |
| */ |
| if (jffs2_is_writebuffered(c)) { |
| /* |
| * We treat 'buf' as 2 adjacent wbufs. We want to |
| * adjust bufstart such as it points to the |
| * beginning of the node within this wbuf. |
| */ |
| bufstart = buf + (ref_offset(ref) % c->wbuf_pagesize); |
| /* We will read either one wbuf or 2 wbufs. */ |
| len = c->wbuf_pagesize - (bufstart - buf); |
| if (JFFS2_MIN_NODE_HEADER + (int)(bufstart - buf) > c->wbuf_pagesize) { |
| /* The header spans the border of the first wbuf */ |
| len += c->wbuf_pagesize; |
| } |
| } else { |
| bufstart = buf; |
| len = JFFS2_MIN_NODE_HEADER; |
| } |
| |
| dbg_readinode("read %d bytes at %#08x(%d).\n", len, ref_offset(ref), ref_flags(ref)); |
| |
| /* FIXME: point() */ |
| err = jffs2_flash_read(c, ref_offset(ref), len, |
| &retlen, bufstart); |
| if (err) { |
| JFFS2_ERROR("can not read %d bytes from 0x%08x, " "error code: %d.\n", len, ref_offset(ref), err); |
| goto free_out; |
| } |
| |
| if (retlen < len) { |
| JFFS2_ERROR("short read at %#08x: %d instead of %d.\n", ref_offset(ref), retlen, len); |
| err = -EIO; |
| goto free_out; |
| } |
| |
| node = (union jffs2_node_union *)bufstart; |
| |
| switch (je16_to_cpu(node->u.nodetype)) { |
| |
| case JFFS2_NODETYPE_DIRENT: |
| |
| if (JFFS2_MIN_NODE_HEADER < sizeof(struct jffs2_raw_dirent)) { |
| err = read_more(c, ref, sizeof(struct jffs2_raw_dirent), &len, buf, bufstart); |
| if (unlikely(err)) |
| goto free_out; |
| } |
| |
| err = read_direntry(c, ref, &node->d, retlen, &ret_fd, latest_mctime, mctime_ver); |
| if (err == 1) { |
| jffs2_mark_node_obsolete(c, ref); |
| break; |
| } else if (unlikely(err)) |
| goto free_out; |
| |
| if (je32_to_cpu(node->d.version) > *highest_version) |
| *highest_version = je32_to_cpu(node->d.version); |
| |
| break; |
| |
| case JFFS2_NODETYPE_INODE: |
| |
| if (JFFS2_MIN_NODE_HEADER < sizeof(struct jffs2_raw_inode)) { |
| err = read_more(c, ref, sizeof(struct jffs2_raw_inode), &len, buf, bufstart); |
| if (unlikely(err)) |
| goto free_out; |
| } |
| |
| err = read_dnode(c, ref, &node->i, &ret_tn, len, latest_mctime, mctime_ver); |
| if (err == 1) { |
| jffs2_mark_node_obsolete(c, ref); |
| break; |
| } else if (unlikely(err)) |
| goto free_out; |
| |
| if (je32_to_cpu(node->i.version) > *highest_version) |
| *highest_version = je32_to_cpu(node->i.version); |
| |
| break; |
| |
| default: |
| if (JFFS2_MIN_NODE_HEADER < sizeof(struct jffs2_unknown_node)) { |
| err = read_more(c, ref, sizeof(struct jffs2_unknown_node), &len, buf, bufstart); |
| if (unlikely(err)) |
| goto free_out; |
| } |
| |
| err = read_unknown(c, ref, &node->u); |
| if (err == 1) { |
| jffs2_mark_node_obsolete(c, ref); |
| break; |
| } else if (unlikely(err)) |
| goto free_out; |
| |
| } |
| spin_lock(&c->erase_completion_lock); |
| } |
| |
| spin_unlock(&c->erase_completion_lock); |
| *tnp = ret_tn; |
| *fdp = ret_fd; |
| kfree(buf); |
| |
| dbg_readinode("nodes of inode #%u were read, the highest version is %u, latest_mctime %u, mctime_ver %u.\n", |
| f->inocache->ino, *highest_version, *latest_mctime, *mctime_ver); |
| return 0; |
| |
| free_out: |
| jffs2_free_tmp_dnode_info_list(&ret_tn); |
| jffs2_free_full_dirent_list(ret_fd); |
| kfree(buf); |
| return err; |
| } |
| |
| static int jffs2_do_read_inode_internal(struct jffs2_sb_info *c, |
| struct jffs2_inode_info *f, |
| struct jffs2_raw_inode *latest_node) |
| { |
| struct jffs2_tmp_dnode_info *tn; |
| struct rb_root tn_list; |
| struct rb_node *rb, *repl_rb; |
| struct jffs2_full_dirent *fd_list; |
| struct jffs2_full_dnode *fn, *first_fn = NULL; |
| uint32_t crc; |
| uint32_t latest_mctime, mctime_ver; |
| size_t retlen; |
| int ret; |
| |
| dbg_readinode("ino #%u nlink is %d\n", f->inocache->ino, f->inocache->nlink); |
| |
| /* Grab all nodes relevant to this ino */ |
| ret = jffs2_get_inode_nodes(c, f, &tn_list, &fd_list, &f->highest_version, &latest_mctime, &mctime_ver); |
| |
| if (ret) { |
| JFFS2_ERROR("cannot read nodes for ino %u, returned error is %d\n", f->inocache->ino, ret); |
| if (f->inocache->state == INO_STATE_READING) |
| jffs2_set_inocache_state(c, f->inocache, INO_STATE_CHECKEDABSENT); |
| return ret; |
| } |
| f->dents = fd_list; |
| |
| rb = rb_first(&tn_list); |
| |
| while (rb) { |
| cond_resched(); |
| tn = rb_entry(rb, struct jffs2_tmp_dnode_info, rb); |
| fn = tn->fn; |
| ret = 1; |
| dbg_readinode("consider node ver %u, phys offset " |
| "%#08x(%d), range %u-%u.\n", tn->version, |
| ref_offset(fn->raw), ref_flags(fn->raw), |
| fn->ofs, fn->ofs + fn->size); |
| |
| if (fn->size) { |
| ret = jffs2_add_older_frag_to_fragtree(c, f, tn); |
| /* TODO: the error code isn't checked, check it */ |
| jffs2_dbg_fragtree_paranoia_check_nolock(f); |
| BUG_ON(ret < 0); |
| if (!first_fn && ret == 0) |
| first_fn = fn; |
| } else if (!first_fn) { |
| first_fn = fn; |
| f->metadata = fn; |
| ret = 0; /* Prevent freeing the metadata update node */ |
| } else |
| jffs2_mark_node_obsolete(c, fn->raw); |
| |
| BUG_ON(rb->rb_left); |
| if (rb->rb_parent && rb->rb_parent->rb_left == rb) { |
| /* We were then left-hand child of our parent. We need |
| * to move our own right-hand child into our place. */ |
| repl_rb = rb->rb_right; |
| if (repl_rb) |
| repl_rb->rb_parent = rb->rb_parent; |
| } else |
| repl_rb = NULL; |
| |
| rb = rb_next(rb); |
| |
| /* Remove the spent tn from the tree; don't bother rebalancing |
| * but put our right-hand child in our own place. */ |
| if (tn->rb.rb_parent) { |
| if (tn->rb.rb_parent->rb_left == &tn->rb) |
| tn->rb.rb_parent->rb_left = repl_rb; |
| else if (tn->rb.rb_parent->rb_right == &tn->rb) |
| tn->rb.rb_parent->rb_right = repl_rb; |
| else BUG(); |
| } else if (tn->rb.rb_right) |
| tn->rb.rb_right->rb_parent = NULL; |
| |
| jffs2_free_tmp_dnode_info(tn); |
| if (ret) { |
| dbg_readinode("delete dnode %u-%u.\n", |
| fn->ofs, fn->ofs + fn->size); |
| jffs2_free_full_dnode(fn); |
| } |
| } |
| jffs2_dbg_fragtree_paranoia_check_nolock(f); |
| |
| BUG_ON(first_fn && ref_obsolete(first_fn->raw)); |
| |
| fn = first_fn; |
| if (unlikely(!first_fn)) { |
| /* No data nodes for this inode. */ |
| if (f->inocache->ino != 1) { |
| JFFS2_WARNING("no data nodes found for ino #%u\n", f->inocache->ino); |
| if (!fd_list) { |
| if (f->inocache->state == INO_STATE_READING) |
| jffs2_set_inocache_state(c, f->inocache, INO_STATE_CHECKEDABSENT); |
| return -EIO; |
| } |
| JFFS2_NOTICE("but it has children so we fake some modes for it\n"); |
| } |
| latest_node->mode = cpu_to_jemode(S_IFDIR|S_IRUGO|S_IWUSR|S_IXUGO); |
| latest_node->version = cpu_to_je32(0); |
| latest_node->atime = latest_node->ctime = latest_node->mtime = cpu_to_je32(0); |
| latest_node->isize = cpu_to_je32(0); |
| latest_node->gid = cpu_to_je16(0); |
| latest_node->uid = cpu_to_je16(0); |
| if (f->inocache->state == INO_STATE_READING) |
| jffs2_set_inocache_state(c, f->inocache, INO_STATE_PRESENT); |
| return 0; |
| } |
| |
| ret = jffs2_flash_read(c, ref_offset(fn->raw), sizeof(*latest_node), &retlen, (void *)latest_node); |
| if (ret || retlen != sizeof(*latest_node)) { |
| JFFS2_ERROR("failed to read from flash: error %d, %zd of %zd bytes read\n", |
| ret, retlen, sizeof(*latest_node)); |
| /* FIXME: If this fails, there seems to be a memory leak. Find it. */ |
| up(&f->sem); |
| jffs2_do_clear_inode(c, f); |
| return ret?ret:-EIO; |
| } |
| |
| crc = crc32(0, latest_node, sizeof(*latest_node)-8); |
| if (crc != je32_to_cpu(latest_node->node_crc)) { |
| JFFS2_ERROR("CRC failed for read_inode of inode %u at physical location 0x%x\n", |
| f->inocache->ino, ref_offset(fn->raw)); |
| up(&f->sem); |
| jffs2_do_clear_inode(c, f); |
| return -EIO; |
| } |
| |
| switch(jemode_to_cpu(latest_node->mode) & S_IFMT) { |
| case S_IFDIR: |
| if (mctime_ver > je32_to_cpu(latest_node->version)) { |
| /* The times in the latest_node are actually older than |
| mctime in the latest dirent. Cheat. */ |
| latest_node->ctime = latest_node->mtime = cpu_to_je32(latest_mctime); |
| } |
| break; |
| |
| |
| case S_IFREG: |
| /* If it was a regular file, truncate it to the latest node's isize */ |
| jffs2_truncate_fragtree(c, &f->fragtree, je32_to_cpu(latest_node->isize)); |
| break; |
| |
| case S_IFLNK: |
| /* Hack to work around broken isize in old symlink code. |
| Remove this when dwmw2 comes to his senses and stops |
| symlinks from being an entirely gratuitous special |
| case. */ |
| if (!je32_to_cpu(latest_node->isize)) |
| latest_node->isize = latest_node->dsize; |
| |
| if (f->inocache->state != INO_STATE_CHECKING) { |
| /* Symlink's inode data is the target path. Read it and |
| * keep in RAM to facilitate quick follow symlink |
| * operation. */ |
| f->target = kmalloc(je32_to_cpu(latest_node->csize) + 1, GFP_KERNEL); |
| if (!f->target) { |
| JFFS2_ERROR("can't allocate %d bytes of memory for the symlink target path cache\n", je32_to_cpu(latest_node->csize)); |
| up(&f->sem); |
| jffs2_do_clear_inode(c, f); |
| return -ENOMEM; |
| } |
| |
| ret = jffs2_flash_read(c, ref_offset(fn->raw) + sizeof(*latest_node), |
| je32_to_cpu(latest_node->csize), &retlen, (char *)f->target); |
| |
| if (ret || retlen != je32_to_cpu(latest_node->csize)) { |
| if (retlen != je32_to_cpu(latest_node->csize)) |
| ret = -EIO; |
| kfree(f->target); |
| f->target = NULL; |
| up(&f->sem); |
| jffs2_do_clear_inode(c, f); |
| return -ret; |
| } |
| |
| f->target[je32_to_cpu(latest_node->csize)] = '\0'; |
| dbg_readinode("symlink's target '%s' cached\n", f->target); |
| } |
| |
| /* fall through... */ |
| |
| case S_IFBLK: |
| case S_IFCHR: |
| /* Certain inode types should have only one data node, and it's |
| kept as the metadata node */ |
| if (f->metadata) { |
| JFFS2_ERROR("Argh. Special inode #%u with mode 0%o had metadata node\n", |
| f->inocache->ino, jemode_to_cpu(latest_node->mode)); |
| up(&f->sem); |
| jffs2_do_clear_inode(c, f); |
| return -EIO; |
| } |
| if (!frag_first(&f->fragtree)) { |
| JFFS2_ERROR("Argh. Special inode #%u with mode 0%o has no fragments\n", |
| f->inocache->ino, jemode_to_cpu(latest_node->mode)); |
| up(&f->sem); |
| jffs2_do_clear_inode(c, f); |
| return -EIO; |
| } |
| /* ASSERT: f->fraglist != NULL */ |
| if (frag_next(frag_first(&f->fragtree))) { |
| JFFS2_ERROR("Argh. Special inode #%u with mode 0x%x had more than one node\n", |
| f->inocache->ino, jemode_to_cpu(latest_node->mode)); |
| /* FIXME: Deal with it - check crc32, check for duplicate node, check times and discard the older one */ |
| up(&f->sem); |
| jffs2_do_clear_inode(c, f); |
| return -EIO; |
| } |
| /* OK. We're happy */ |
| f->metadata = frag_first(&f->fragtree)->node; |
| jffs2_free_node_frag(frag_first(&f->fragtree)); |
| f->fragtree = RB_ROOT; |
| break; |
| } |
| if (f->inocache->state == INO_STATE_READING) |
| jffs2_set_inocache_state(c, f->inocache, INO_STATE_PRESENT); |
| |
| return 0; |
| } |
| |
| /* Scan the list of all nodes present for this ino, build map of versions, etc. */ |
| int jffs2_do_read_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f, |
| uint32_t ino, struct jffs2_raw_inode *latest_node) |
| { |
| dbg_readinode("read inode #%u\n", ino); |
| |
| retry_inocache: |
| spin_lock(&c->inocache_lock); |
| f->inocache = jffs2_get_ino_cache(c, ino); |
| |
| if (f->inocache) { |
| /* Check its state. We may need to wait before we can use it */ |
| switch(f->inocache->state) { |
| case INO_STATE_UNCHECKED: |
| case INO_STATE_CHECKEDABSENT: |
| f->inocache->state = INO_STATE_READING; |
| break; |
| |
| case INO_STATE_CHECKING: |
| case INO_STATE_GC: |
| /* If it's in either of these states, we need |
| to wait for whoever's got it to finish and |
| put it back. */ |
| dbg_readinode("waiting for ino #%u in state %d\n", ino, f->inocache->state); |
| sleep_on_spinunlock(&c->inocache_wq, &c->inocache_lock); |
| goto retry_inocache; |
| |
| case INO_STATE_READING: |
| case INO_STATE_PRESENT: |
| /* Eep. This should never happen. It can |
| happen if Linux calls read_inode() again |
| before clear_inode() has finished though. */ |
| JFFS2_ERROR("Eep. Trying to read_inode #%u when it's already in state %d!\n", ino, f->inocache->state); |
| /* Fail. That's probably better than allowing it to succeed */ |
| f->inocache = NULL; |
| break; |
| |
| default: |
| BUG(); |
| } |
| } |
| spin_unlock(&c->inocache_lock); |
| |
| if (!f->inocache && ino == 1) { |
| /* Special case - no root inode on medium */ |
| f->inocache = jffs2_alloc_inode_cache(); |
| if (!f->inocache) { |
| JFFS2_ERROR("cannot allocate inocache for root inode\n"); |
| return -ENOMEM; |
| } |
| dbg_readinode("creating inocache for root inode\n"); |
| memset(f->inocache, 0, sizeof(struct jffs2_inode_cache)); |
| f->inocache->ino = f->inocache->nlink = 1; |
| f->inocache->nodes = (struct jffs2_raw_node_ref *)f->inocache; |
| f->inocache->state = INO_STATE_READING; |
| jffs2_add_ino_cache(c, f->inocache); |
| } |
| if (!f->inocache) { |
| JFFS2_ERROR("requestied to read an nonexistent ino %u\n", ino); |
| return -ENOENT; |
| } |
| |
| return jffs2_do_read_inode_internal(c, f, latest_node); |
| } |
| |
| int jffs2_do_crccheck_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic) |
| { |
| struct jffs2_raw_inode n; |
| struct jffs2_inode_info *f = kmalloc(sizeof(*f), GFP_KERNEL); |
| int ret; |
| |
| if (!f) |
| return -ENOMEM; |
| |
| memset(f, 0, sizeof(*f)); |
| init_MUTEX_LOCKED(&f->sem); |
| f->inocache = ic; |
| |
| ret = jffs2_do_read_inode_internal(c, f, &n); |
| if (!ret) { |
| up(&f->sem); |
| jffs2_do_clear_inode(c, f); |
| } |
| kfree (f); |
| return ret; |
| } |
| |
| void jffs2_do_clear_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f) |
| { |
| struct jffs2_full_dirent *fd, *fds; |
| int deleted; |
| |
| down(&f->sem); |
| deleted = f->inocache && !f->inocache->nlink; |
| |
| if (f->inocache && f->inocache->state != INO_STATE_CHECKING) |
| jffs2_set_inocache_state(c, f->inocache, INO_STATE_CLEARING); |
| |
| if (f->metadata) { |
| if (deleted) |
| jffs2_mark_node_obsolete(c, f->metadata->raw); |
| jffs2_free_full_dnode(f->metadata); |
| } |
| |
| jffs2_kill_fragtree(&f->fragtree, deleted?c:NULL); |
| |
| if (f->target) { |
| kfree(f->target); |
| f->target = NULL; |
| } |
| |
| fds = f->dents; |
| while(fds) { |
| fd = fds; |
| fds = fd->next; |
| jffs2_free_full_dirent(fd); |
| } |
| |
| if (f->inocache && f->inocache->state != INO_STATE_CHECKING) { |
| jffs2_set_inocache_state(c, f->inocache, INO_STATE_CHECKEDABSENT); |
| if (f->inocache->nodes == (void *)f->inocache) |
| jffs2_del_ino_cache(c, f->inocache); |
| } |
| |
| up(&f->sem); |
| } |