[JFFS2] Add symlink caching support. (32f1a95d) · Commits · git / linux-net

fs/jffs2/dir.c

+21 −7

Original line number	Diff line number	Diff line
		@@ -7,7 +7,7 @@
		*
		* For licensing information, see the file 'LICENCE' in this directory.
		*
		* $Id: dir.c,v 1.84 2004/11/16 20:36:11 dwmw2 Exp $
		* $Id: dir.c,v 1.85 2005/03/01 10:34:03 dedekind Exp $
		*
		*/

		@@ -296,11 +296,11 @@ static int jffs2_symlink (struct inode dir_i, struct dentry dentry, const char
		struct jffs2_full_dirent *fd;
		int namelen;
		uint32_t alloclen, phys_ofs;
		int ret;
		int ret, targetlen = strlen(target);

		/* FIXME: If you care. We'd need to use frags for the target
		if it grows much more than this */
		if (strlen(target) > 254)
		if (targetlen > 254)
		return -EINVAL;

		ri = jffs2_alloc_raw_inode();
		@@ -314,7 +314,7 @@ static int jffs2_symlink (struct inode dir_i, struct dentry dentry, const char
		* Just the node will do for now, though
		*/
		namelen = dentry->d_name.len;
		ret = jffs2_reserve_space(c, sizeof(*ri) + strlen(target), &phys_ofs, &alloclen, ALLOC_NORMAL);
		ret = jffs2_reserve_space(c, sizeof(*ri) + targetlen, &phys_ofs, &alloclen, ALLOC_NORMAL);

		if (ret) {
		jffs2_free_raw_inode(ri);
		@@ -333,16 +333,16 @@ static int jffs2_symlink (struct inode dir_i, struct dentry dentry, const char

		f = JFFS2_INODE_INFO(inode);

		inode->i_size = strlen(target);
		inode->i_size = targetlen;
		ri->isize = ri->dsize = ri->csize = cpu_to_je32(inode->i_size);
		ri->totlen = cpu_to_je32(sizeof(*ri) + inode->i_size);
		ri->hdr_crc = cpu_to_je32(crc32(0, ri, sizeof(struct jffs2_unknown_node)-4));

		ri->compr = JFFS2_COMPR_NONE;
		ri->data_crc = cpu_to_je32(crc32(0, target, strlen(target)));
		ri->data_crc = cpu_to_je32(crc32(0, target, targetlen));
		ri->node_crc = cpu_to_je32(crc32(0, ri, sizeof(*ri)-8));

		fn = jffs2_write_dnode(c, f, ri, target, strlen(target), phys_ofs, ALLOC_NORMAL);
		fn = jffs2_write_dnode(c, f, ri, target, targetlen, phys_ofs, ALLOC_NORMAL);

		jffs2_free_raw_inode(ri);

		@@ -353,6 +353,20 @@ static int jffs2_symlink (struct inode dir_i, struct dentry dentry, const char
		jffs2_clear_inode(inode);
		return PTR_ERR(fn);
		}

		/* We use f->dents field to store the target path. */
		f->dents = kmalloc(targetlen + 1, GFP_KERNEL);
		if (!f->dents) {
		printk(KERN_WARNING "Can't allocate %d bytes of memory\n", targetlen + 1);
		up(&f->sem);
		jffs2_complete_reservation(c);
		jffs2_clear_inode(inode);
		return -ENOMEM;
		}

		memcpy(f->dents, target, targetlen + 1);
		D1(printk(KERN_DEBUG "jffs2_symlink: symlink's target '%s' cached\n", (char *)f->dents));

		/* No data here. Only a metadata node, which will be
		obsoleted by the first data write
		*/

fs/jffs2/read.c

+1 −31

Original line number	Diff line number	Diff line
		@@ -7,7 +7,7 @@
		*
		* For licensing information, see the file 'LICENCE' in this directory.
		*
		* $Id: read.c,v 1.38 2004/11/16 20:36:12 dwmw2 Exp $
		* $Id: read.c,v 1.39 2005/03/01 10:34:03 dedekind Exp $
		*
		*/

		@@ -214,33 +214,3 @@ int jffs2_read_inode_range(struct jffs2_sb_info c, struct jffs2_inode_info f,
		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;
		}

fs/jffs2/readinode.c

+48 −6

Original line number	Diff line number	Diff line
		@@ -7,7 +7,7 @@
		*
		* For licensing information, see the file 'LICENCE' in this directory.
		*
		* $Id: readinode.c,v 1.118 2005/02/27 23:01:33 dwmw2 Exp $
		* $Id: readinode.c,v 1.119 2005/03/01 10:34:03 dedekind Exp $
		*
		*/

		@@ -623,6 +623,40 @@ static int jffs2_do_read_inode_internal(struct jffs2_sb_info *c,
		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.
		* We use f->dents field to store the target path, which
		* is somewhat ugly. */
		f->dents = kmalloc(je32_to_cpu(latest_node->csize) + 1, GFP_KERNEL);
		if (!f->dents) {
		printk(KERN_WARNING "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->dents);

		if (ret \|\| retlen != je32_to_cpu(latest_node->csize)) {
		if (retlen != je32_to_cpu(latest_node->csize))
		ret = -EIO;
		kfree(f->dents);
		f->dents = NULL;
		up(&f->sem);
		jffs2_do_clear_inode(c, f);
		return -ret;
		}

		((char *)f->dents)[je32_to_cpu(latest_node->csize)] = '\0';
		D1(printk(KERN_DEBUG "jffs2_do_read_inode(): symlink's target '%s' cached\n",
		(char *)f->dents));
		}

		/* fall through... */

		case S_IFBLK:
		@@ -683,6 +717,13 @@ void jffs2_do_clear_inode(struct jffs2_sb_info c, struct jffs2_inode_info f)

		jffs2_kill_fragtree(&f->fragtree, deleted?c:NULL);

		/* For symlink inodes we us f->dents to store the target path name */
		if (S_ISLNK(OFNI_EDONI_2SFFJ(f)->i_mode)) {
		if (f->dents) {
		kfree(f->dents);
		f->dents = NULL;
		}
		} else {
		fds = f->dents;

		while(fds) {
		@@ -690,6 +731,7 @@ void jffs2_do_clear_inode(struct jffs2_sb_info c, struct jffs2_inode_info f)
		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);

fs/jffs2/symlink.c

+30 −12

Original line number	Diff line number	Diff line
		@@ -7,7 +7,7 @@
		*
		* For licensing information, see the file 'LICENCE' in this directory.
		*
		* $Id: symlink.c,v 1.14 2004/11/16 20:36:12 dwmw2 Exp $
		* $Id: symlink.c,v 1.16 2005/03/01 10:50:48 dedekind Exp $
		*
		*/

		@@ -19,27 +19,45 @@
		#include "nodelist.h"

		static int jffs2_follow_link(struct dentry dentry, struct nameidata nd);
		static void jffs2_put_link(struct dentry dentry, struct nameidata nd);

		struct inode_operations jffs2_symlink_inode_operations =
		{
		.readlink = generic_readlink,
		.follow_link = jffs2_follow_link,
		.put_link = jffs2_put_link,
		.setattr = jffs2_setattr
		};

		static int jffs2_follow_link(struct dentry dentry, struct nameidata nd)
		{
		unsigned char *buf;
		buf = jffs2_getlink(JFFS2_SB_INFO(dentry->d_inode->i_sb), JFFS2_INODE_INFO(dentry->d_inode));
		nd_set_link(nd, buf);
		return 0;
		struct jffs2_inode_info *f = JFFS2_INODE_INFO(dentry->d_inode);

		/*
		* We don't acquire the f->sem mutex here since the only data we
		* use is f->dents which in case of the symlink inode points to the
		* symlink's target path.
		*
		* 1. If we are here the inode has already built and f->dents has
		* to point to the target path.
		* 2. Nobody uses f->dents (if the inode is symlink's inode). The
		* exception is inode freeing function which frees f->dents. But
		* it can't be called while we are here and before VFS has
		* stopped using our f->dents string which we provide by means of
		* nd_set_link() call.
		*/

		if (!f->dents) {
		printk(KERN_ERR "jffs2_follow_link(): can't find symlink taerget\n");
		return -EIO;
		}
		D1(printk(KERN_DEBUG "jffs2_follow_link(): target path is '%s'\n", (char *) f->dents));

		static void jffs2_put_link(struct dentry dentry, struct nameidata nd)
		{
		char *s = nd_get_link(nd);
		if (!IS_ERR(s))
		kfree(s);
		nd_set_link(nd, (char *)f->dents);

		/*
		* We unlock the f->sem mutex but VFS will use the f->dents string. This is safe
		* since the only way that may cause f->dents to be changed is iput() operation.
		* But VFS will not use f->dents after iput() has been called.
		*/
		return 0;
		}

fs/jffs2/write.c

+17 −14

Original line number	Diff line number	Diff line
		@@ -7,7 +7,7 @@
		*
		* For licensing information, see the file 'LICENCE' in this directory.
		*
		* $Id: write.c,v 1.90 2005/01/28 18:53:01 hammache Exp $
		* $Id: write.c,v 1.91 2005/03/01 10:34:03 dedekind Exp $
		*
		*/

		@@ -644,6 +644,7 @@ int jffs2_do_unlink(struct jffs2_sb_info c, struct jffs2_inode_info dir_f,

		down(&dead_f->sem);

		if (S_ISDIR(OFNI_EDONI_2SFFJ(dead_f)->i_mode)) {
		while (dead_f->dents) {
		/* There can be only deleted ones */
		fd = dead_f->dents;
		@@ -654,11 +655,13 @@ int jffs2_do_unlink(struct jffs2_sb_info c, struct jffs2_inode_info dir_f,
		printk(KERN_WARNING "Deleting inode #%u with active dentry \"%s\"->ino #%u\n",
		dead_f->inocache->ino, fd->name, fd->ino);
		} else {
		D1(printk(KERN_DEBUG "Removing deletion dirent for \"%s\" from dir ino #%u\n", fd->name, dead_f->inocache->ino));
		D1(printk(KERN_DEBUG "Removing deletion dirent for \"%s\" from dir ino #%u\n",
		fd->name, dead_f->inocache->ino));
		}
		jffs2_mark_node_obsolete(c, fd->raw);
		jffs2_free_full_dirent(fd);
		}
		}

		dead_f->inocache->nlink--;
		/* NB: Caller must set inode nlink if appropriate */