patch-2.4.10 linux/fs/jffs2/file.c

• Lines: 542
• Date: Fri Sep 14 14:04:07 2001
• Orig file: v2.4.9/linux/fs/jffs2/file.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.4.9/linux/fs/jffs2/file.c linux/fs/jffs2/file.c
@@ -0,0 +1,541 @@
+/*
+ * 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: file.c,v 1.55 2001/05/29 09:19:24 dwmw2 Exp $
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/fs.h>
+#include <linux/pagemap.h>
+#include <linux/jffs2.h>
+#include "nodelist.h"
+#include "crc32.h"
+
+extern int generic_file_open(struct inode *, struct file *) __attribute__((weak));
+
+
+int jffs2_null_fsync(struct file *filp, struct dentry *dentry, int datasync)
+{
+	/* Move along. Nothing to see here */
+	return 0;
+}
+
+struct file_operations jffs2_file_operations =
+{
+	llseek:		generic_file_llseek,
+	open:		generic_file_open,
+	read:		generic_file_read,
+	write:		generic_file_write,
+	ioctl:		jffs2_ioctl,
+	mmap:		generic_file_mmap,
+	fsync:		jffs2_null_fsync
+};
+
+/* jffs2_file_inode_operations */
+
+struct inode_operations jffs2_file_inode_operations =
+{
+	setattr:	jffs2_setattr
+};
+
+struct address_space_operations jffs2_file_address_operations =
+{
+	readpage:	jffs2_readpage,
+	prepare_write:	jffs2_prepare_write,
+	commit_write:	jffs2_commit_write
+};
+
+int jffs2_setattr (struct dentry *dentry, struct iattr *iattr)
+{
+	struct jffs2_full_dnode *old_metadata, *new_metadata;
+	struct inode *inode = dentry->d_inode;
+	struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
+	struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
+	struct jffs2_raw_inode *ri;
+	unsigned short dev;
+	unsigned char *mdata = NULL;
+	int mdatalen = 0;
+	unsigned int ivalid;
+	__u32 phys_ofs, alloclen;
+	int ret;
+	D1(printk(KERN_DEBUG "jffs2_setattr(): ino #%lu\n", inode->i_ino));
+	ret = inode_change_ok(inode, iattr);
+	if (ret) 
+		return ret;
+
+	/* Special cases - we don't want more than one data node
+	   for these types on the medium at any time. So setattr
+	   must read the original data associated with the node
+	   (i.e. the device numbers or the target name) and write
+	   it out again with the appropriate data attached */
+	if ((inode->i_mode & S_IFMT) == S_IFBLK ||
+	    (inode->i_mode & S_IFMT) == S_IFCHR) {
+		/* For these, we don't actually need to read the old node */
+		dev =  (MAJOR(to_kdev_t(dentry->d_inode->i_rdev)) << 8) | 
+			MINOR(to_kdev_t(dentry->d_inode->i_rdev));
+		mdata = (char *)&dev;
+		mdatalen = sizeof(dev);
+		D1(printk(KERN_DEBUG "jffs2_setattr(): Writing %d bytes of kdev_t\n", mdatalen));
+	} else if ((inode->i_mode & S_IFMT) == S_IFLNK) {
+		mdatalen = f->metadata->size;
+		mdata = kmalloc(f->metadata->size, GFP_USER);
+		if (!mdata)
+			return -ENOMEM;
+		ret = jffs2_read_dnode(c, f->metadata, mdata, 0, mdatalen);
+		if (ret) {
+			kfree(mdata);
+			return ret;
+		}
+		D1(printk(KERN_DEBUG "jffs2_setattr(): Writing %d bytes of symlink target\n", mdatalen));
+	}
+
+	ri = jffs2_alloc_raw_inode();
+	if (!ri) {
+		if ((inode->i_mode & S_IFMT) == S_IFLNK)
+			kfree(mdata);
+		return -ENOMEM;
+	}
+		
+	ret = jffs2_reserve_space(c, sizeof(*ri) + mdatalen, &phys_ofs, &alloclen, ALLOC_NORMAL);
+	if (ret) {
+		jffs2_free_raw_inode(ri);
+		if ((inode->i_mode & S_IFMT) == S_IFLNK)
+			 kfree(mdata);
+		return ret;
+	}
+	down(&f->sem);
+        ivalid = iattr->ia_valid;
+	
+	ri->magic = JFFS2_MAGIC_BITMASK;
+	ri->nodetype = JFFS2_NODETYPE_INODE;
+	ri->totlen = sizeof(*ri) + mdatalen;
+	ri->hdr_crc = crc32(0, ri, sizeof(struct jffs2_unknown_node)-4);
+
+	ri->ino = inode->i_ino;
+	ri->version = ++f->highest_version;
+
+	ri->mode = (ivalid & ATTR_MODE)?iattr->ia_mode:inode->i_mode;
+	ri->uid = (ivalid & ATTR_UID)?iattr->ia_uid:inode->i_uid;
+	ri->gid = (ivalid & ATTR_GID)?iattr->ia_gid:inode->i_gid;
+
+	if (ivalid & ATTR_MODE && ri->mode & S_ISGID &&
+	    !in_group_p(ri->gid) && !capable(CAP_FSETID))
+		ri->mode &= ~S_ISGID;
+
+	ri->isize = (ivalid & ATTR_SIZE)?iattr->ia_size:inode->i_size;
+	ri->atime = (ivalid & ATTR_ATIME)?iattr->ia_atime:inode->i_atime;
+	ri->mtime = (ivalid & ATTR_MTIME)?iattr->ia_mtime:inode->i_mtime;
+	ri->ctime = (ivalid & ATTR_CTIME)?iattr->ia_ctime:inode->i_ctime;
+
+	ri->offset = 0;
+	ri->csize = ri->dsize = mdatalen;
+	ri->compr = JFFS2_COMPR_NONE;
+	if (inode->i_size < ri->isize) {
+		/* It's an extension. Make it a hole node */
+		ri->compr = JFFS2_COMPR_ZERO;
+		ri->dsize = ri->isize - inode->i_size;
+		ri->offset = inode->i_size;
+	}
+	ri->node_crc = crc32(0, ri, sizeof(*ri)-8);
+	if (mdatalen)
+		ri->data_crc = crc32(0, mdata, mdatalen);
+	else
+		ri->data_crc = 0;
+
+	new_metadata = jffs2_write_dnode(inode, ri, mdata, mdatalen, phys_ofs, NULL);
+	if ((inode->i_mode & S_IFMT) == S_IFLNK)
+		kfree(mdata);
+
+	jffs2_complete_reservation(c);
+	
+	if (IS_ERR(new_metadata)) {
+		jffs2_free_raw_inode(ri);
+		up(&f->sem);
+		return PTR_ERR(new_metadata);
+	}
+	/* It worked. Update the inode */
+	inode->i_atime = ri->atime;
+	inode->i_ctime = ri->ctime;
+	inode->i_mtime = ri->mtime;
+	inode->i_mode = ri->mode;
+	inode->i_uid = ri->uid;
+	inode->i_gid = ri->gid;
+
+
+	old_metadata = f->metadata;
+
+	if (inode->i_size > ri->isize) {
+		vmtruncate(inode, ri->isize);
+		jffs2_truncate_fraglist (c, &f->fraglist, ri->isize);
+	}
+
+	if (inode->i_size < ri->isize) {
+		jffs2_add_full_dnode_to_inode(c, f, new_metadata);
+		inode->i_size = ri->isize;
+		f->metadata = NULL;
+	} else {
+		f->metadata = new_metadata;
+	}
+	if (old_metadata) {
+		jffs2_mark_node_obsolete(c, old_metadata->raw);
+		jffs2_free_full_dnode(old_metadata);
+	}
+	jffs2_free_raw_inode(ri);
+	up(&f->sem);
+	return 0;
+}
+
+int jffs2_do_readpage_nolock (struct inode *inode, struct page *pg)
+{
+	struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
+	struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
+	struct jffs2_node_frag *frag = f->fraglist;
+	__u32 offset = pg->index << PAGE_CACHE_SHIFT;
+	__u32 end = offset + PAGE_CACHE_SIZE;
+	unsigned char *pg_buf;
+	int ret;
+
+	D1(printk(KERN_DEBUG "jffs2_do_readpage_nolock(): ino #%lu, page at offset 0x%x\n", inode->i_ino, offset));
+
+	if (!PageLocked(pg))
+                PAGE_BUG(pg);
+
+	while(frag && frag->ofs + frag->size  <= offset) {
+		//		D1(printk(KERN_DEBUG "skipping frag %d-%d; before the region we care about\n", frag->ofs, frag->ofs + frag->size));
+		frag = frag->next;
+	}
+
+	pg_buf = kmap(pg);
+
+	/* 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_readpage: offset %d, end %d\n", offset, end));
+		if (!frag || frag->ofs > offset) {
+			__u32 holesize = end - offset;
+			if (frag) {
+				D1(printk(KERN_NOTICE "Eep. Hole in ino %ld fraglist. frag->ofs = 0x%08x, offset = 0x%08x\n", inode->i_ino, frag->ofs, offset));
+				holesize = min(holesize, frag->ofs - offset);
+				D1(jffs2_print_frag_list(f));
+			}
+			D1(printk(KERN_DEBUG "Filling non-frag hole from %d-%d\n", offset, offset+holesize));
+			memset(pg_buf, 0, holesize);
+			pg_buf += holesize;
+			offset += holesize;
+			continue;
+		} else if (frag->ofs < offset && (offset & (PAGE_CACHE_SIZE-1)) != 0) {
+			D1(printk(KERN_NOTICE "Eep. Overlap in ino #%ld fraglist. frag->ofs = 0x%08x, offset = 0x%08x\n",
+				  inode->i_ino, frag->ofs, offset));
+			D1(jffs2_print_frag_list(f));
+			memset(pg_buf, 0, end - offset);
+			ClearPageUptodate(pg);
+			SetPageError(pg);
+			kunmap(pg);
+			return -EIO;
+		} else if (!frag->node) {
+			__u32 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(pg_buf, 0, holeend - offset);
+			pg_buf += holeend - offset;
+			offset = holeend;
+			frag = frag->next;
+			continue;
+		} else {
+			__u32 readlen;
+			readlen = min(frag->size, end - offset);
+			D1(printk(KERN_DEBUG "Reading %d-%d from node at 0x%x\n", frag->ofs, frag->ofs+readlen, frag->node->raw->flash_offset & ~3));
+			ret = jffs2_read_dnode(c, frag->node, pg_buf, frag->ofs - frag->node->ofs, readlen);
+			D2(printk(KERN_DEBUG "node read done\n"));
+			if (ret) {
+				D1(printk(KERN_DEBUG"jffs2_readpage error %d\n",ret));
+				memset(pg_buf, 0, frag->size);
+				ClearPageUptodate(pg);
+				SetPageError(pg);
+				kunmap(pg);
+				return ret;
+			}
+		}
+		pg_buf += frag->size;
+		offset += frag->size;
+		frag = frag->next;
+		D2(printk(KERN_DEBUG "node read was OK. Looping\n"));
+	}
+	D2(printk(KERN_DEBUG "readpage finishing\n"));
+	SetPageUptodate(pg);
+	ClearPageError(pg);
+
+	flush_dcache_page(pg);
+
+	kunmap(pg);
+	D1(printk(KERN_DEBUG "readpage finished\n"));
+	return 0;
+}
+
+int jffs2_do_readpage_unlock(struct inode *inode, struct page *pg)
+{
+	int ret = jffs2_do_readpage_nolock(inode, pg);
+	UnlockPage(pg);
+	return ret;
+}
+
+
+int jffs2_readpage (struct file *filp, struct page *pg)
+{
+	struct jffs2_inode_info *f = JFFS2_INODE_INFO(filp->f_dentry->d_inode);
+	int ret;
+	
+	down(&f->sem);
+	ret = jffs2_do_readpage_unlock(filp->f_dentry->d_inode, pg);
+	up(&f->sem);
+	return ret;
+}
+
+int jffs2_prepare_write (struct file *filp, struct page *pg, unsigned start, unsigned end)
+{
+	struct inode *inode = filp->f_dentry->d_inode;
+	struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
+	__u32 pageofs = pg->index << PAGE_CACHE_SHIFT;
+	int ret = 0;
+
+	down(&f->sem);
+	D1(printk(KERN_DEBUG "jffs2_prepare_write() nrpages %ld\n", inode->i_mapping->nrpages));
+
+	if (pageofs > inode->i_size) {
+		/* Make new hole frag from old EOF to new page */
+		struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
+		struct jffs2_raw_inode ri;
+		struct jffs2_full_dnode *fn;
+		__u32 phys_ofs, alloc_len;
+		
+		D1(printk(KERN_DEBUG "Writing new hole frag 0x%x-0x%x between current EOF and new page\n",
+			  (unsigned int)inode->i_size, pageofs));
+
+		ret = jffs2_reserve_space(c, sizeof(ri), &phys_ofs, &alloc_len, ALLOC_NORMAL);
+		if (ret) {
+			up(&f->sem);
+			return ret;
+		}
+		memset(&ri, 0, sizeof(ri));
+
+		ri.magic = JFFS2_MAGIC_BITMASK;
+		ri.nodetype = JFFS2_NODETYPE_INODE;
+		ri.totlen = sizeof(ri);
+		ri.hdr_crc = crc32(0, &ri, sizeof(struct jffs2_unknown_node)-4);
+
+		ri.ino = f->inocache->ino;
+		ri.version = ++f->highest_version;
+		ri.mode = inode->i_mode;
+		ri.uid = inode->i_uid;
+		ri.gid = inode->i_gid;
+		ri.isize = max(inode->i_size, pageofs);
+		ri.atime = ri.ctime = ri.mtime = CURRENT_TIME;
+		ri.offset = inode->i_size;
+		ri.dsize = pageofs - inode->i_size;
+		ri.csize = 0;
+		ri.compr = JFFS2_COMPR_ZERO;
+		ri.node_crc = crc32(0, &ri, sizeof(ri)-8);
+		ri.data_crc = 0;
+		
+		fn = jffs2_write_dnode(inode, &ri, NULL, 0, phys_ofs, NULL);
+		jffs2_complete_reservation(c);
+		if (IS_ERR(fn)) {
+			ret = PTR_ERR(fn);
+			up(&f->sem);
+			return ret;
+		}
+		ret = jffs2_add_full_dnode_to_inode(c, f, fn);
+		if (f->metadata) {
+			jffs2_mark_node_obsolete(c, f->metadata->raw);
+			jffs2_free_full_dnode(f->metadata);
+			f->metadata = NULL;
+		}
+		if (ret) {
+			D1(printk(KERN_DEBUG "Eep. add_full_dnode_to_inode() failed in prepare_write, returned %d\n", ret));
+			jffs2_mark_node_obsolete(c, fn->raw);
+			jffs2_free_full_dnode(fn);
+			up(&f->sem);
+			return ret;
+		}
+		inode->i_size = pageofs;
+	}
+	
+
+	/* Read in the page if it wasn't already present */
+	if (!Page_Uptodate(pg) && (start || end < PAGE_SIZE))
+		ret = jffs2_do_readpage_nolock(inode, pg);
+	D1(printk(KERN_DEBUG "end prepare_write(). nrpages %ld\n", inode->i_mapping->nrpages));
+	up(&f->sem);
+	return ret;
+}
+
+int jffs2_commit_write (struct file *filp, struct page *pg, unsigned start, unsigned end)
+{
+	/* Actually commit the write from the page cache page we're looking at.
+	 * For now, we write the full page out each time. It sucks, but it's simple
+	 */
+	struct inode *inode = filp->f_dentry->d_inode;
+	struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
+	struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
+	ssize_t newsize = max(filp->f_dentry->d_inode->i_size, (pg->index << PAGE_CACHE_SHIFT) + end);
+	__u32 file_ofs = (pg->index << PAGE_CACHE_SHIFT);
+	unsigned writelen = min(PAGE_CACHE_SIZE, newsize - file_ofs);
+	struct jffs2_raw_inode *ri;
+	int ret = 0;
+	ssize_t writtenlen = 0;
+
+	D1(printk(KERN_DEBUG "jffs2_commit_write(): ino #%lu, page at 0x%lx, range %d-%d, nrpages %ld\n", inode->i_ino, pg->index << PAGE_CACHE_SHIFT, start, end, filp->f_dentry->d_inode->i_mapping->nrpages));
+
+	ri = jffs2_alloc_raw_inode();
+	if (!ri)
+		return -ENOMEM;
+
+	while(writelen) {
+		struct jffs2_full_dnode *fn;
+		unsigned char *comprbuf = NULL;
+		unsigned char comprtype = JFFS2_COMPR_NONE;
+		__u32 phys_ofs, alloclen;
+		__u32 datalen, cdatalen;
+
+		D2(printk(KERN_DEBUG "jffs2_commit_write() loop: 0x%x to write to 0x%x\n", writelen, file_ofs));
+
+		ret = jffs2_reserve_space(c, sizeof(*ri) + JFFS2_MIN_DATA_LEN, &phys_ofs, &alloclen, ALLOC_NORMAL);
+		if (ret) {
+			SetPageError(pg);
+			D1(printk(KERN_DEBUG "jffs2_reserve_space returned %d\n", ret));
+			break;
+		}
+		down(&f->sem);
+		datalen = writelen;
+		cdatalen = min(alloclen - sizeof(*ri), writelen);
+
+		comprbuf = kmalloc(cdatalen, GFP_KERNEL);
+		if (comprbuf) {
+			comprtype = jffs2_compress(page_address(pg)+ (file_ofs & (PAGE_CACHE_SIZE-1)), comprbuf, &datalen, &cdatalen);
+		}
+		if (comprtype == JFFS2_COMPR_NONE) {
+			/* Either compression failed, or the allocation of comprbuf failed */
+			if (comprbuf)
+				kfree(comprbuf);
+			comprbuf = page_address(pg) + (file_ofs & (PAGE_CACHE_SIZE -1));
+			datalen = cdatalen;
+		}
+		/* Now comprbuf points to the data to be written, be it compressed or not.
+		   comprtype holds the compression type, and comprtype == JFFS2_COMPR_NONE means
+		   that the comprbuf doesn't need to be kfree()d. 
+		*/
+
+		ri->magic = JFFS2_MAGIC_BITMASK;
+		ri->nodetype = JFFS2_NODETYPE_INODE;
+		ri->totlen = sizeof(*ri) + cdatalen;
+		ri->hdr_crc = crc32(0, ri, sizeof(struct jffs2_unknown_node)-4);
+
+		ri->ino = inode->i_ino;
+		ri->version = ++f->highest_version;
+		ri->mode = inode->i_mode;
+		ri->uid = inode->i_uid;
+		ri->gid = inode->i_gid;
+		ri->isize = max(inode->i_size, file_ofs + datalen);
+		ri->atime = ri->ctime = ri->mtime = CURRENT_TIME;
+		ri->offset = file_ofs;
+		ri->csize = cdatalen;
+		ri->dsize = datalen;
+		ri->compr = comprtype;
+		ri->node_crc = crc32(0, ri, sizeof(*ri)-8);
+		ri->data_crc = crc32(0, comprbuf, cdatalen);
+
+		fn = jffs2_write_dnode(inode, ri, comprbuf, cdatalen, phys_ofs, NULL);
+
+		jffs2_complete_reservation(c);
+
+		if (comprtype != JFFS2_COMPR_NONE)
+			kfree(comprbuf);
+
+		if (IS_ERR(fn)) {
+			ret = PTR_ERR(fn);
+			up(&f->sem);
+			SetPageError(pg);
+			break;
+		}
+		ret = jffs2_add_full_dnode_to_inode(c, f, fn);
+		if (f->metadata) {
+			jffs2_mark_node_obsolete(c, f->metadata->raw);
+			jffs2_free_full_dnode(f->metadata);
+			f->metadata = NULL;
+		}
+		up(&f->sem);
+		if (ret) {
+			/* Eep */
+			D1(printk(KERN_DEBUG "Eep. add_full_dnode_to_inode() failed in commit_write, returned %d\n", ret));
+			jffs2_mark_node_obsolete(c, fn->raw);
+			jffs2_free_full_dnode(fn);
+			SetPageError(pg);
+			break;
+		}
+		inode->i_size = ri->isize;
+		inode->i_blocks = (inode->i_size + 511) >> 9;
+		inode->i_ctime = inode->i_mtime = ri->ctime;
+		if (!datalen) {
+			printk(KERN_WARNING "Eep. We didn't actually write any bloody data\n");
+			ret = -EIO;
+			SetPageError(pg);
+			break;
+		}
+		D1(printk(KERN_DEBUG "increasing writtenlen by %d\n", datalen));
+		writtenlen += datalen;
+		file_ofs += datalen;
+		writelen -= datalen;
+	}
+
+	jffs2_free_raw_inode(ri);
+
+	if (writtenlen < end) {
+		/* generic_file_write has written more to the page cache than we've
+		   actually written to the medium. Mark the page !Uptodate so that 
+		   it gets reread */
+		D1(printk(KERN_DEBUG "jffs2_commit_write(): Not all bytes written. Marking page !uptodate\n"));
+		SetPageError(pg);
+		ClearPageUptodate(pg);
+	}
+	if (writtenlen <= start) {
+		/* We didn't even get to the start of the affected part */
+		ret = ret?ret:-ENOSPC;
+		D1(printk(KERN_DEBUG "jffs2_commit_write(): Only %x bytes written to page. start (%x) not reached, returning %d\n", writtenlen, start, ret));
+	}
+	writtenlen = min(end-start, writtenlen-start);
+
+	D1(printk(KERN_DEBUG "jffs2_commit_write() returning %d. nrpages is %ld\n",writtenlen?writtenlen:ret, inode->i_mapping->nrpages));
+	return writtenlen?writtenlen:ret;
+}