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/*
* JFFS2 -- Journalling Flash File System, Version 2.
*
* Copyright (C) 2001 Red Hat, Inc.
*
* Created by David Woodhouse <dwmw2@cambridge.redhat.com>
*
* The original JFFS, from which the design for JFFS2 was derived,
* was designed and implemented by Axis Communications AB.
*
* The contents of this file are subject to the Red Hat eCos Public
* License Version 1.1 (the "Licence"); you may not use this file
* except in compliance with the Licence. You may obtain a copy of
* the Licence at http://www.redhat.com/
*
* Software distributed under the Licence is distributed on an "AS IS"
* basis, WITHOUT WARRANTY OF ANY KIND, either express or implied.
* See the Licence for the specific language governing rights and
* limitations under the Licence.
*
* The Original Code is JFFS2 - Journalling Flash File System, version 2
*
* Alternatively, the contents of this file may be used under the
* terms of the GNU General Public License version 2 (the "GPL"), in
* which case the provisions of the GPL are applicable instead of the
* above. If you wish to allow the use of your version of this file
* only under the terms of the GPL and not to allow others to use your
* version of this file under the RHEPL, indicate your decision by
* deleting the provisions above and replace them with the notice and
* other provisions required by the GPL. If you do not delete the
* provisions above, a recipient may use your version of this file
* under either the RHEPL or the GPL.
*
* $Id: readinode.c,v 1.57 2001/12/27 22:49:46 dwmw2 Exp $
*
*/
/* Given an inode, probably with existing list of fragments, add the new node
* to the fragment list.
*/
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/mtd/mtd.h>
#include <linux/jffs2.h>
#include "nodelist.h"
#include "crc32.h"
D1(void jffs2_print_frag_list(struct jffs2_inode_info *f)
{
struct jffs2_node_frag *this = f->fraglist;
while(this) {
if (this->node)
printk(KERN_DEBUG "frag %04x-%04x: 0x%08x on flash (*%p->%p)\n", this->ofs, this->ofs+this->size, this->node->raw->flash_offset &~3, this, this->next);
else
printk(KERN_DEBUG "frag %04x-%04x: hole (*%p->%p)\n", this->ofs, this->ofs+this->size, this, this->next);
this = this->next;
}
if (f->metadata) {
printk(KERN_DEBUG "metadata at 0x%08x\n", f->metadata->raw->flash_offset &~3);
}
})
int jffs2_add_full_dnode_to_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f, struct jffs2_full_dnode *fn)
{
int ret;
D1(printk(KERN_DEBUG "jffs2_add_full_dnode_to_inode(ino #%u, f %p, fn %p)\n", f->inocache->ino, f, fn));
ret = jffs2_add_full_dnode_to_fraglist(c, &f->fraglist, fn);
D2(jffs2_print_frag_list(f));
return ret;
}
static void jffs2_obsolete_node_frag(struct jffs2_sb_info *c, struct jffs2_node_frag *this)
{
if (this->node) {
this->node->frags--;
if (!this->node->frags) {
/* The node has no valid frags left. It's totally obsoleted */
D2(printk(KERN_DEBUG "Marking old node @0x%08x (0x%04x-0x%04x) obsolete\n",
this->node->raw->flash_offset &~3, this->node->ofs, this->node->ofs+this->node->size));
jffs2_mark_node_obsolete(c, this->node->raw);
jffs2_free_full_dnode(this->node);
} else {
D2(printk(KERN_DEBUG "Not marking old node @0x%08x (0x%04x-0x%04x) obsolete. frags is %d\n",
this->node->raw->flash_offset &~3, this->node->ofs, this->node->ofs+this->node->size,
this->node->frags));
}
}
jffs2_free_node_frag(this);
}
/* Doesn't set inode->i_size */
int jffs2_add_full_dnode_to_fraglist(struct jffs2_sb_info *c, struct jffs2_node_frag **list, struct jffs2_full_dnode *fn)
{
struct jffs2_node_frag *this, **prev, *old;
struct jffs2_node_frag *newfrag, *newfrag2;
__u32 lastend = 0;
newfrag = jffs2_alloc_node_frag();
if (!newfrag) {
return -ENOMEM;
}
D2(if (fn->raw)
printk(KERN_DEBUG "adding node %04x-%04x @0x%08x on flash, newfrag *%p\n", fn->ofs, fn->ofs+fn->size, fn->raw->flash_offset &~3, newfrag);
else
printk(KERN_DEBUG "adding hole node %04x-%04x on flash, newfrag *%p\n", fn->ofs, fn->ofs+fn->size, newfrag));
prev = list;
this = *list;
if (!fn->size) {
jffs2_free_node_frag(newfrag);
return 0;
}
newfrag->ofs = fn->ofs;
newfrag->size = fn->size;
newfrag->node = fn;
newfrag->node->frags = 1;
newfrag->next = (void *)0xdeadbeef;
/* Skip all the nodes which are completed before this one starts */
while(this && fn->ofs >= this->ofs+this->size) {
lastend = this->ofs + this->size;
D2(printk(KERN_DEBUG "j_a_f_d_t_f: skipping frag 0x%04x-0x%04x; phys 0x%08x (*%p->%p)\n",
this->ofs, this->ofs+this->size, this->node?(this->node->raw->flash_offset &~3):0xffffffff, this, this->next));
prev = &this->next;
this = this->next;
}
/* See if we ran off the end of the list */
if (!this) {
/* We did */
if (lastend < fn->ofs) {
/* ... and we need to put a hole in before the new node */
struct jffs2_node_frag *holefrag = jffs2_alloc_node_frag();
if (!holefrag)
return -ENOMEM;
holefrag->ofs = lastend;
holefrag->size = fn->ofs - lastend;
holefrag->next = NULL;
holefrag->node = NULL;
*prev = holefrag;
prev = &holefrag->next;
}
newfrag->next = NULL;
*prev = newfrag;
return 0;
}
D2(printk(KERN_DEBUG "j_a_f_d_t_f: dealing with frag 0x%04x-0x%04x; phys 0x%08x (*%p->%p)\n",
this->ofs, this->ofs+this->size, this->node?(this->node->raw->flash_offset &~3):0xffffffff, this, this->next));
/* OK. 'this' is pointing at the first frag that fn->ofs at least partially obsoletes,
* - i.e. fn->ofs < this->ofs+this->size && fn->ofs >= this->ofs
*/
if (fn->ofs > this->ofs) {
/* This node isn't completely obsoleted. The start of it remains valid */
if (this->ofs + this->size > fn->ofs + fn->size) {
/* The new node splits 'this' frag into two */
newfrag2 = jffs2_alloc_node_frag();
if (!newfrag2) {
jffs2_free_node_frag(newfrag);
return -ENOMEM;
}
printk(KERN_DEBUG "split old frag 0x%04x-0x%04x -->", this->ofs, this->ofs+this->size);
if (this->node)
printk("phys 0x%08x\n", this->node->raw->flash_offset &~3);
else
printk("hole\n");
newfrag2->ofs = fn->ofs + fn->size;
newfrag2->size = (this->ofs+this->size) - newfrag2->ofs;
newfrag2->next = this->next;
newfrag2->node = this->node;
if (this->node)
this->node->frags++;
newfrag->next = newfrag2;
this->next = newfrag;
this->size = newfrag->ofs - this->ofs;
return 0;
}
/* New node just reduces 'this' frag in size, doesn't split it */
this->size = fn->ofs - this->ofs;
newfrag->next = this->next;
this->next = newfrag;
this = newfrag->next;
} else {
D2(printk(KERN_DEBUG "Inserting newfrag (*%p) in before 'this' (*%p)\n", newfrag, this));
*prev = newfrag;
newfrag->next = this;
}
/* OK, now we have newfrag added in the correct place in the list, but
newfrag->next points to a fragment which may be overlapping it
*/
while (this && newfrag->ofs + newfrag->size >= this->ofs + this->size) {
/* 'this' frag is obsoleted. */
old = this;
this = old->next;
jffs2_obsolete_node_frag(c, old);
}
/* Now we're pointing at the first frag which isn't totally obsoleted by
the new frag */
newfrag->next = this;
if (!this || newfrag->ofs + newfrag->size == this->ofs) {
return 0;
}
/* Still some overlap */
this->size = (this->ofs + this->size) - (newfrag->ofs + newfrag->size);
this->ofs = newfrag->ofs + newfrag->size;
return 0;
}
void jffs2_truncate_fraglist (struct jffs2_sb_info *c, struct jffs2_node_frag **list, __u32 size)
{
D1(printk(KERN_DEBUG "Truncating fraglist to 0x%08x bytes\n", size));
while (*list) {
if ((*list)->ofs >= size) {
struct jffs2_node_frag *this = *list;
*list = this->next;
D1(printk(KERN_DEBUG "Removing frag 0x%08x-0x%08x\n", this->ofs, this->ofs+this->size));
jffs2_obsolete_node_frag(c, this);
continue;
} else if ((*list)->ofs + (*list)->size > size) {
D1(printk(KERN_DEBUG "Truncating frag 0x%08x-0x%08x\n", (*list)->ofs, (*list)->ofs + (*list)->size));
(*list)->size = size - (*list)->ofs;
}
list = &(*list)->next;
}
}
/* Scan the list of all nodes present for this ino, build map of versions, etc. */
void jffs2_read_inode (struct inode *inode)
{
struct jffs2_tmp_dnode_info *tn_list, *tn;
struct jffs2_full_dirent *fd_list;
struct jffs2_inode_info *f;
struct jffs2_full_dnode *fn = NULL;
struct jffs2_sb_info *c;
struct jffs2_raw_inode latest_node;
int ret;
ssize_t retlen;
D1(printk(KERN_DEBUG "jffs2_read_inode(): inode->i_ino == %lu\n", inode->i_ino));
f = JFFS2_INODE_INFO(inode);
c = JFFS2_SB_INFO(inode->i_sb);
memset(f, 0, sizeof(*f));
D2(printk(KERN_DEBUG "getting inocache\n"));
init_MUTEX(&f->sem);
f->inocache = jffs2_get_ino_cache(c, inode->i_ino);
D2(printk(KERN_DEBUG "jffs2_read_inode(): Got inocache at %p\n", f->inocache));
if (!f->inocache && inode->i_ino == 1) {
/* Special case - no root inode on medium */
f->inocache = jffs2_alloc_inode_cache();
if (!f->inocache) {
printk(KERN_CRIT "jffs2_read_inode(): Cannot allocate inocache for root inode\n");
make_bad_inode(inode);
return;
}
D1(printk(KERN_DEBUG "jffs2_read_inode(): 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;
jffs2_add_ino_cache(c, f->inocache);
}
if (!f->inocache) {
printk(KERN_WARNING "jffs2_read_inode() on nonexistent ino %lu\n", (unsigned long)inode->i_ino);
make_bad_inode(inode);
return;
}
D1(printk(KERN_DEBUG "jffs2_read_inode(): ino #%lu nlink is %d\n", (unsigned long)inode->i_ino, f->inocache->nlink));
inode->i_nlink = f->inocache->nlink;
/* Grab all nodes relevant to this ino */
ret = jffs2_get_inode_nodes(c, inode->i_ino, f, &tn_list, &fd_list, &f->highest_version);
if (ret) {
printk(KERN_CRIT "jffs2_get_inode_nodes() for ino %lu returned %d\n", inode->i_ino, ret);
make_bad_inode(inode);
return;
}
f->dents = fd_list;
while (tn_list) {
static __u32 mdata_ver = 0;
tn = tn_list;
fn = tn->fn;
if (f->metadata && tn->version > mdata_ver) {
D1(printk(KERN_DEBUG "Obsoleting old metadata at 0x%08x\n", f->metadata->raw->flash_offset &~3));
jffs2_mark_node_obsolete(c, f->metadata->raw);
jffs2_free_full_dnode(f->metadata);
f->metadata = NULL;
mdata_ver = 0;
}
if (fn->size) {
jffs2_add_full_dnode_to_inode(c, f, fn);
} else {
/* Zero-sized node at end of version list. Just a metadata update */
D1(printk(KERN_DEBUG "metadata @%08x: ver %d\n", fn->raw->flash_offset &~3, tn->version));
f->metadata = fn;
mdata_ver = tn->version;
}
tn_list = tn->next;
jffs2_free_tmp_dnode_info(tn);
}
if (!fn) {
/* No data nodes for this inode. */
if (inode->i_ino != 1) {
printk(KERN_WARNING "jffs2_read_inode(): No data nodes found for ino #%lu\n", inode->i_ino);
if (!fd_list) {
make_bad_inode(inode);
return;
}
printk(KERN_WARNING "jffs2_read_inode(): But it has children so we fake some modes for it\n");
}
inode->i_mode = S_IFDIR | S_IRUGO | S_IWUSR | S_IXUGO;
inode->i_atime = inode->i_ctime = inode->i_mtime = CURRENT_TIME;
inode->i_nlink = f->inocache->nlink;
inode->i_size = 0;
} else {
__u32 crc;
ret = c->mtd->read(c->mtd, fn->raw->flash_offset & ~3, sizeof(latest_node), &retlen, (void *)&latest_node);
if (ret || retlen != sizeof(latest_node)) {
printk(KERN_NOTICE "MTD read in jffs2_read_inode() failed: Returned %d, %ld of %d bytes read\n",
ret, (long)retlen, sizeof(latest_node));
jffs2_clear_inode(inode);
make_bad_inode(inode);
return;
}
crc = crc32(0, &latest_node, sizeof(latest_node)-8);
if (crc != latest_node.node_crc) {
printk(KERN_NOTICE "CRC failed for read_inode of inode %ld at physical location 0x%x\n", inode->i_ino, fn->raw->flash_offset & ~3);
jffs2_clear_inode(inode);
make_bad_inode(inode);
return;
}
inode->i_mode = latest_node.mode;
inode->i_uid = latest_node.uid;
inode->i_gid = latest_node.gid;
inode->i_size = latest_node.isize;
if ((inode->i_mode & S_IFMT) == S_IFREG)
jffs2_truncate_fraglist(c, &f->fraglist, latest_node.isize);
inode->i_atime = latest_node.atime;
inode->i_mtime = latest_node.mtime;
inode->i_ctime = latest_node.ctime;
}
/* OK, now the special cases. Certain inode types should
have only one data node, and it's kept as the metadata
node */
if ((inode->i_mode & S_IFMT) == S_IFBLK ||
(inode->i_mode & S_IFMT) == S_IFCHR ||
(inode->i_mode & S_IFMT) == S_IFLNK) {
if (f->metadata) {
printk(KERN_WARNING "Argh. Special inode #%lu with mode 0%o had metadata node\n", inode->i_ino, inode->i_mode);
jffs2_clear_inode(inode);
make_bad_inode(inode);
return;
}
if (!f->fraglist) {
printk(KERN_WARNING "Argh. Special inode #%lu with mode 0%o has no fragments\n", inode->i_ino, inode->i_mode);
jffs2_clear_inode(inode);
make_bad_inode(inode);
return;
}
/* ASSERT: f->fraglist != NULL */
if (f->fraglist->next) {
printk(KERN_WARNING "Argh. Special inode #%lu had more than one node\n", inode->i_ino);
jffs2_clear_inode(inode);
make_bad_inode(inode);
return;
}
/* OK. We're happy */
f->metadata = f->fraglist->node;
jffs2_free_node_frag(f->fraglist);
f->fraglist = NULL;
}
inode->i_blksize = PAGE_SIZE;
inode->i_blocks = (inode->i_size + 511) >> 9;
switch (inode->i_mode & S_IFMT) {
unsigned short rdev;
case S_IFLNK:
inode->i_op = &jffs2_symlink_inode_operations;
/* 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 (!inode->i_size)
inode->i_size = latest_node.dsize;
break;
case S_IFDIR:
inode->i_op = &jffs2_dir_inode_operations;
inode->i_fop = &jffs2_dir_operations;
break;
case S_IFREG:
inode->i_op = &jffs2_file_inode_operations;
inode->i_fop = &jffs2_file_operations;
inode->i_mapping->a_ops = &jffs2_file_address_operations;
inode->i_mapping->nrpages = 0;
break;
case S_IFBLK:
case S_IFCHR:
/* Read the device numbers from the media */
D1(printk(KERN_DEBUG "Reading device numbers from flash\n"));
if (jffs2_read_dnode(c, f->metadata, (char *)&rdev, 0, sizeof(rdev)) < 0) {
/* Eep */
printk(KERN_NOTICE "Read device numbers for inode %lu failed\n", (unsigned long)inode->i_ino);
jffs2_clear_inode(inode);
make_bad_inode(inode);
return;
}
case S_IFSOCK:
case S_IFIFO:
inode->i_op = &jffs2_file_inode_operations;
init_special_inode(inode, inode->i_mode, kdev_t_to_nr(MKDEV(rdev>>8, rdev&0xff)));
break;
default:
printk(KERN_WARNING "jffs2_read_inode(): Bogus imode %o for ino %lu", inode->i_mode, (unsigned long)inode->i_ino);
}
D1(printk(KERN_DEBUG "jffs2_read_inode() returning\n"));
}
void jffs2_clear_inode (struct inode *inode)
{
/* We can forget about this inode for now - drop all
* the nodelists associated with it, etc.
*/
struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
struct jffs2_node_frag *frag, *frags;
struct jffs2_full_dirent *fd, *fds;
struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
D1(printk(KERN_DEBUG "jffs2_clear_inode(): ino #%lu mode %o\n", inode->i_ino, inode->i_mode));
frags = f->fraglist;
fds = f->dents;
if (f->metadata) {
if (!f->inocache->nlink)
jffs2_mark_node_obsolete(c, f->metadata->raw);
jffs2_free_full_dnode(f->metadata);
}
while (frags) {
frag = frags;
frags = frag->next;
D2(printk(KERN_DEBUG "jffs2_clear_inode: frag at 0x%x-0x%x: node %p, frags %d--\n", frag->ofs, frag->ofs+frag->size, frag->node, frag->node?frag->node->frags:0));
if (frag->node && !(--frag->node->frags)) {
/* Not a hole, and it's the final remaining frag of this node. Free the node */
if (!f->inocache->nlink)
jffs2_mark_node_obsolete(c, frag->node->raw);
jffs2_free_full_dnode(frag->node);
}
jffs2_free_node_frag(frag);
}
while(fds) {
fd = fds;
fds = fd->next;
jffs2_free_full_dirent(fd);
}
// if (!f->inocache->nlink) {
// D1(printk(KERN_DEBUG "jffs2_clear_inode() deleting inode #%lu\n", inode->i_ino));
// jffs2_del_ino_cache(JFFS2_SB_INFO(inode->i_sb), f->inocache);
// jffs2_free_inode_cache(f->inocache);
// }
};
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