Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 246 insertions, 0 deletions

diff --git a/fs/jffs2/read.c b/fs/jffs2/read.c
new file mode 100644
index 000000000000..eb493dc06db7
--- /dev/null
+++ b/fs/jffs2/read.c
@@ -0,0 +1,246 @@
+/*
+ * 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: read.c,v 1.38 2004/11/16 20:36:12 dwmw2 Exp $
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/crc32.h>
+#include <linux/pagemap.h>
+#include <linux/mtd/mtd.h>
+#include <linux/compiler.h>
+#include "nodelist.h"
+#include "compr.h"
+
+int jffs2_read_dnode(struct jffs2_sb_info *c, struct jffs2_inode_info *f,
+                     struct jffs2_full_dnode *fd, unsigned char *buf,
+                     int ofs, int len)
+{
+        struct jffs2_raw_inode *ri;
+        size_t readlen;
+        uint32_t crc;
+        unsigned char *decomprbuf = NULL;
+        unsigned char *readbuf = NULL;
+        int ret = 0;
+
+        ri = jffs2_alloc_raw_inode();
+        if (!ri)
+                return -ENOMEM;
+
+        ret = jffs2_flash_read(c, ref_offset(fd->raw), sizeof(*ri), &readlen, (char *)ri);
+        if (ret) {
+                jffs2_free_raw_inode(ri);
+                printk(KERN_WARNING "Error reading node from 0x%08x: %d\n", ref_offset(fd->raw), ret);
+                return ret;
+        }
+        if (readlen != sizeof(*ri)) {
+                jffs2_free_raw_inode(ri);
+                printk(KERN_WARNING "Short read from 0x%08x: wanted 0x%zx bytes, got 0x%zx\n", 
+                       ref_offset(fd->raw), sizeof(*ri), readlen);
+                return -EIO;
+        }
+        crc = crc32(0, ri, sizeof(*ri)-8);
+
+        D1(printk(KERN_DEBUG "Node read from %08x: node_crc %08x, calculated CRC %08x. dsize %x, csize %x, offset %x, buf %p\n",
+                  ref_offset(fd->raw), je32_to_cpu(ri->node_crc),
+                  crc, je32_to_cpu(ri->dsize), je32_to_cpu(ri->csize),
+                  je32_to_cpu(ri->offset), buf));
+        if (crc != je32_to_cpu(ri->node_crc)) {
+                printk(KERN_WARNING "Node CRC %08x != calculated CRC %08x for node at %08x\n",
+                       je32_to_cpu(ri->node_crc), crc, ref_offset(fd->raw));
+                ret = -EIO;
+                goto out_ri;
+        }
+        /* There was a bug where we wrote hole nodes out with csize/dsize
+           swapped. Deal with it */
+        if (ri->compr == JFFS2_COMPR_ZERO && !je32_to_cpu(ri->dsize) && 
+            je32_to_cpu(ri->csize)) {
+                ri->dsize = ri->csize;
+                ri->csize = cpu_to_je32(0);
+        }
+
+        D1(if(ofs + len > je32_to_cpu(ri->dsize)) {
+                printk(KERN_WARNING "jffs2_read_dnode() asked for %d bytes at %d from %d-byte node\n",
+                       len, ofs, je32_to_cpu(ri->dsize));
+                ret = -EINVAL;
+                goto out_ri;
+        });
+
+        
+        if (ri->compr == JFFS2_COMPR_ZERO) {
+                memset(buf, 0, len);
+                goto out_ri;
+        }
+
+        /* Cases:
+           Reading whole node and it's uncompressed - read directly to buffer provided, check CRC.
+           Reading whole node and it's compressed - read into comprbuf, check CRC and decompress to buffer provided 
+           Reading partial node and it's uncompressed - read into readbuf, check CRC, and copy 
+           Reading partial node and it's compressed - read into readbuf, check checksum, decompress to decomprbuf and copy
+        */
+        if (ri->compr == JFFS2_COMPR_NONE && len == je32_to_cpu(ri->dsize)) {
+                readbuf = buf;
+        } else {
+                readbuf = kmalloc(je32_to_cpu(ri->csize), GFP_KERNEL);
+                if (!readbuf) {
+                        ret = -ENOMEM;
+                        goto out_ri;
+                }
+        }
+        if (ri->compr != JFFS2_COMPR_NONE) {
+                if (len < je32_to_cpu(ri->dsize)) {
+                        decomprbuf = kmalloc(je32_to_cpu(ri->dsize), GFP_KERNEL);
+                        if (!decomprbuf) {
+                                ret = -ENOMEM;
+                                goto out_readbuf;
+                        }
+                } else {
+                        decomprbuf = buf;
+                }
+        } else {
+                decomprbuf = readbuf;
+        }
+
+        D2(printk(KERN_DEBUG "Read %d bytes to %p\n", je32_to_cpu(ri->csize),
+                  readbuf));
+        ret = jffs2_flash_read(c, (ref_offset(fd->raw)) + sizeof(*ri),
+                               je32_to_cpu(ri->csize), &readlen, readbuf);
+
+        if (!ret && readlen != je32_to_cpu(ri->csize))
+                ret = -EIO;
+        if (ret)
+                goto out_decomprbuf;
+
+        crc = crc32(0, readbuf, je32_to_cpu(ri->csize));
+        if (crc != je32_to_cpu(ri->data_crc)) {
+                printk(KERN_WARNING "Data CRC %08x != calculated CRC %08x for node at %08x\n",
+                       je32_to_cpu(ri->data_crc), crc, ref_offset(fd->raw));
+                ret = -EIO;
+                goto out_decomprbuf;
+        }
+        D2(printk(KERN_DEBUG "Data CRC matches calculated CRC %08x\n", crc));
+        if (ri->compr != JFFS2_COMPR_NONE) {
+                D2(printk(KERN_DEBUG "Decompress %d bytes from %p to %d bytes at %p\n",
+                          je32_to_cpu(ri->csize), readbuf, je32_to_cpu(ri->dsize), decomprbuf)); 
+                ret = jffs2_decompress(c, f, ri->compr | (ri->usercompr << 8), readbuf, decomprbuf, je32_to_cpu(ri->csize), je32_to_cpu(ri->dsize));
+                if (ret) {
+                        printk(KERN_WARNING "Error: jffs2_decompress returned %d\n", ret);
+                        goto out_decomprbuf;
+                }
+        }
+
+        if (len < je32_to_cpu(ri->dsize)) {
+                memcpy(buf, decomprbuf+ofs, len);
+        }
+ out_decomprbuf:
+        if(decomprbuf != buf && decomprbuf != readbuf)
+                kfree(decomprbuf);
+ out_readbuf:
+        if(readbuf != buf)
+                kfree(readbuf);
+ out_ri:
+        jffs2_free_raw_inode(ri);
+
+        return ret;
+}
+
+int jffs2_read_inode_range(struct jffs2_sb_info *c, struct jffs2_inode_info *f,
+                           unsigned char *buf, uint32_t offset, uint32_t len)
+{
+        uint32_t end = offset + len;
+        struct jffs2_node_frag *frag;
+        int ret;
+
+        D1(printk(KERN_DEBUG "jffs2_read_inode_range: ino #%u, range 0x%08x-0x%08x\n",
+                  f->inocache->ino, offset, offset+len));
+
+        frag = jffs2_lookup_node_frag(&f->fragtree, offset);
+
+        /* XXX FIXME: Where a single physical node actually shows up in two
+           frags, we read it twice. Don't do that. */
+        /* Now we're pointing at the first frag which overlaps our page */
+        while(offset < end) {
+                D2(printk(KERN_DEBUG "jffs2_read_inode_range: offset %d, end %d\n", offset, end));
+                if (unlikely(!frag || frag->ofs > offset)) {
+                        uint32_t holesize = end - offset;
+                        if (frag) {
+                                D1(printk(KERN_NOTICE "Eep. Hole in ino #%u fraglist. frag->ofs = 0x%08x, offset = 0x%08x\n", f->inocache->ino, frag->ofs, offset));
+                                holesize = min(holesize, frag->ofs - offset);
+                                D2(jffs2_print_frag_list(f));
+                        }
+                        D1(printk(KERN_DEBUG "Filling non-frag hole from %d-%d\n", offset, offset+holesize));
+                        memset(buf, 0, holesize);
+                        buf += holesize;
+                        offset += holesize;
+                        continue;
+                } else if (unlikely(!frag->node)) {
+                        uint32_t holeend = min(end, frag->ofs + frag->size);
+                        D1(printk(KERN_DEBUG "Filling frag hole from %d-%d (frag 0x%x 0x%x)\n", offset, holeend, frag->ofs, frag->ofs + frag->size));
+                        memset(buf, 0, holeend - offset);
+                        buf += holeend - offset;
+                        offset = holeend;
+                        frag = frag_next(frag);
+                        continue;
+                } else {
+                        uint32_t readlen;
+                        uint32_t fragofs; /* offset within the frag to start reading */
+                        
+                        fragofs = offset - frag->ofs;
+                        readlen = min(frag->size - fragofs, end - offset);
+                        D1(printk(KERN_DEBUG "Reading %d-%d from node at 0x%08x (%d)\n",
+                                  frag->ofs+fragofs, frag->ofs+fragofs+readlen,
+                                  ref_offset(frag->node->raw), ref_flags(frag->node->raw)));
+                        ret = jffs2_read_dnode(c, f, frag->node, buf, fragofs + frag->ofs - frag->node->ofs, readlen);
+                        D2(printk(KERN_DEBUG "node read done\n"));
+                        if (ret) {
+                                D1(printk(KERN_DEBUG"jffs2_read_inode_range error %d\n",ret));
+                                memset(buf, 0, readlen);
+                                return ret;
+                        }
+                        buf += readlen;
+                        offset += readlen;
+                        frag = frag_next(frag);
+                        D2(printk(KERN_DEBUG "node read was OK. Looping\n"));
+                }
+        }
+        return 0;
+}
+
+/* Core function to read symlink target. */
+char *jffs2_getlink(struct jffs2_sb_info *c, struct jffs2_inode_info *f)
+{
+        char *buf;
+        int ret;
+
+        down(&f->sem);
+
+        if (!f->metadata) {
+                printk(KERN_NOTICE "No metadata for symlink inode #%u\n", f->inocache->ino);
+                up(&f->sem);
+                return ERR_PTR(-EINVAL);
+        }
+        buf = kmalloc(f->metadata->size+1, GFP_USER);
+        if (!buf) {
+                up(&f->sem);
+                return ERR_PTR(-ENOMEM);
+        }
+        buf[f->metadata->size]=0;
+
+        ret = jffs2_read_dnode(c, f, f->metadata, buf, 0, f->metadata->size);
+
+        up(&f->sem);
+
+        if (ret) {
+                kfree(buf);
+                return ERR_PTR(ret);
+        }
+        return buf;
+}