From 27c72b040c0be8f3704ed0b6b84c12cbba24a7e8 Mon Sep 17 00:00:00 2001 From: David Woodhouse Date: Thu, 1 May 2008 18:47:17 +0100 Subject: [PATCH] [JFFS2] Track parent inode for directories (for NFS export) To support NFS export, we need to know the parent inode of directories. Rather than growing the jffs2_inode_cache structure, share space with the nlink field -- which was always set to 1 for directories anyway. Signed-off-by: David Woodhouse --- fs/jffs2/build.c | 31 ++++++++++++++++++++----------- fs/jffs2/dir.c | 35 +++++++++++++++++++++++++---------- fs/jffs2/erase.c | 2 +- fs/jffs2/fs.c | 5 ++--- fs/jffs2/gc.c | 6 +++--- fs/jffs2/nodelist.h | 5 ++++- fs/jffs2/nodemgmt.c | 2 +- fs/jffs2/readinode.c | 7 ++++--- fs/jffs2/scan.c | 2 +- fs/jffs2/wbuf.c | 2 +- fs/jffs2/write.c | 11 ++++++----- fs/jffs2/xattr.c | 4 ++-- 12 files changed, 70 insertions(+), 42 deletions(-) diff --git a/fs/jffs2/build.c b/fs/jffs2/build.c index d58f845ccb8..c5e1450d79f 100644 --- a/fs/jffs2/build.c +++ b/fs/jffs2/build.c @@ -46,7 +46,7 @@ next_inode(int *i, struct jffs2_inode_cache *ic, struct jffs2_sb_info *c) static void jffs2_build_inode_pass1(struct jffs2_sb_info *c, - struct jffs2_inode_cache *ic) + struct jffs2_inode_cache *ic) { struct jffs2_full_dirent *fd; @@ -68,11 +68,17 @@ static void jffs2_build_inode_pass1(struct jffs2_sb_info *c, continue; } - if (child_ic->nlink++ && fd->type == DT_DIR) { - JFFS2_ERROR("child dir \"%s\" (ino #%u) of dir ino #%u appears to be a hard link\n", - fd->name, fd->ino, ic->ino); - /* TODO: What do we do about it? */ - } + if (fd->type == DT_DIR) { + if (child_ic->pino_nlink) { + JFFS2_ERROR("child dir \"%s\" (ino #%u) of dir ino #%u appears to be a hard link\n", + fd->name, fd->ino, ic->ino); + /* TODO: What do we do about it? */ + } else { + child_ic->pino_nlink = ic->ino; + } + } else + child_ic->pino_nlink++; + dbg_fsbuild("increased nlink for child \"%s\" (ino #%u)\n", fd->name, fd->ino); /* Can't free scan_dents so far. We might need them in pass 2 */ } @@ -125,7 +131,7 @@ static int jffs2_build_filesystem(struct jffs2_sb_info *c) dbg_fsbuild("pass 2 starting\n"); for_each_inode(i, c, ic) { - if (ic->nlink) + if (ic->pino_nlink) continue; jffs2_build_remove_unlinked_inode(c, ic, &dead_fds); @@ -232,16 +238,19 @@ static void jffs2_build_remove_unlinked_inode(struct jffs2_sb_info *c, /* Reduce nlink of the child. If it's now zero, stick it on the dead_fds list to be cleaned up later. Else just free the fd */ - child_ic->nlink--; + if (fd->type == DT_DIR) + child_ic->pino_nlink = 0; + else + child_ic->pino_nlink--; - if (!child_ic->nlink) { - dbg_fsbuild("inode #%u (\"%s\") has now got zero nlink, adding to dead_fds list.\n", + if (!child_ic->pino_nlink) { + dbg_fsbuild("inode #%u (\"%s\") now has no links; adding to dead_fds list.\n", fd->ino, fd->name); fd->next = *dead_fds; *dead_fds = fd; } else { dbg_fsbuild("inode #%u (\"%s\") has now got nlink %d. Ignoring.\n", - fd->ino, fd->name, child_ic->nlink); + fd->ino, fd->name, child_ic->pino_nlink); jffs2_free_full_dirent(fd); } } diff --git a/fs/jffs2/dir.c b/fs/jffs2/dir.c index 2bba3d3435b..c0c141f6fde 100644 --- a/fs/jffs2/dir.c +++ b/fs/jffs2/dir.c @@ -226,7 +226,8 @@ static int jffs2_create(struct inode *dir_i, struct dentry *dentry, int mode, d_instantiate(dentry, inode); D1(printk(KERN_DEBUG "jffs2_create: Created ino #%lu with mode %o, nlink %d(%d). nrpages %ld\n", - inode->i_ino, inode->i_mode, inode->i_nlink, f->inocache->nlink, inode->i_mapping->nrpages)); + inode->i_ino, inode->i_mode, inode->i_nlink, + f->inocache->pino_nlink, inode->i_mapping->nrpages)); return 0; fail: @@ -250,7 +251,7 @@ static int jffs2_unlink(struct inode *dir_i, struct dentry *dentry) ret = jffs2_do_unlink(c, dir_f, dentry->d_name.name, dentry->d_name.len, dead_f, now); if (dead_f->inocache) - dentry->d_inode->i_nlink = dead_f->inocache->nlink; + dentry->d_inode->i_nlink = dead_f->inocache->pino_nlink; if (!ret) dir_i->i_mtime = dir_i->i_ctime = ITIME(now); return ret; @@ -283,7 +284,7 @@ static int jffs2_link (struct dentry *old_dentry, struct inode *dir_i, struct de if (!ret) { mutex_lock(&f->sem); - old_dentry->d_inode->i_nlink = ++f->inocache->nlink; + old_dentry->d_inode->i_nlink = ++f->inocache->pino_nlink; mutex_unlock(&f->sem); d_instantiate(dentry, old_dentry->d_inode); dir_i->i_mtime = dir_i->i_ctime = ITIME(now); @@ -500,11 +501,14 @@ static int jffs2_mkdir (struct inode *dir_i, struct dentry *dentry, int mode) inode->i_op = &jffs2_dir_inode_operations; inode->i_fop = &jffs2_dir_operations; - /* Directories get nlink 2 at start */ - inode->i_nlink = 2; f = JFFS2_INODE_INFO(inode); + /* Directories get nlink 2 at start */ + inode->i_nlink = 2; + /* but ic->pino_nlink is the parent ino# */ + f->inocache->pino_nlink = dir_i->i_ino; + ri->data_crc = cpu_to_je32(0); ri->node_crc = cpu_to_je32(crc32(0, ri, sizeof(*ri)-8)); @@ -601,17 +605,25 @@ static int jffs2_mkdir (struct inode *dir_i, struct dentry *dentry, int mode) static int jffs2_rmdir (struct inode *dir_i, struct dentry *dentry) { + struct jffs2_sb_info *c = JFFS2_SB_INFO(dir_i->i_sb); + struct jffs2_inode_info *dir_f = JFFS2_INODE_INFO(dir_i); struct jffs2_inode_info *f = JFFS2_INODE_INFO(dentry->d_inode); struct jffs2_full_dirent *fd; int ret; + uint32_t now = get_seconds(); for (fd = f->dents ; fd; fd = fd->next) { if (fd->ino) return -ENOTEMPTY; } - ret = jffs2_unlink(dir_i, dentry); - if (!ret) + + ret = jffs2_do_unlink(c, dir_f, dentry->d_name.name, + dentry->d_name.len, f, now); + if (!ret) { + dir_i->i_mtime = dir_i->i_ctime = ITIME(now); + clear_nlink(dentry->d_inode); drop_nlink(dir_i); + } return ret; } @@ -824,7 +836,10 @@ static int jffs2_rename (struct inode *old_dir_i, struct dentry *old_dentry, inode which didn't exist. */ if (victim_f->inocache) { mutex_lock(&victim_f->sem); - victim_f->inocache->nlink--; + if (S_ISDIR(new_dentry->d_inode->i_mode)) + victim_f->inocache->pino_nlink = 0; + else + victim_f->inocache->pino_nlink--; mutex_unlock(&victim_f->sem); } } @@ -845,8 +860,8 @@ static int jffs2_rename (struct inode *old_dir_i, struct dentry *old_dentry, struct jffs2_inode_info *f = JFFS2_INODE_INFO(old_dentry->d_inode); mutex_lock(&f->sem); inc_nlink(old_dentry->d_inode); - if (f->inocache) - f->inocache->nlink++; + if (f->inocache && !S_ISDIR(old_dentry->d_inode->i_mode)) + f->inocache->pino_nlink++; mutex_unlock(&f->sem); printk(KERN_NOTICE "jffs2_rename(): Link succeeded, unlink failed (err %d). You now have a hard link\n", ret); diff --git a/fs/jffs2/erase.c b/fs/jffs2/erase.c index 25a640e566d..5e86f43616a 100644 --- a/fs/jffs2/erase.c +++ b/fs/jffs2/erase.c @@ -294,7 +294,7 @@ static inline void jffs2_remove_node_refs_from_ino_list(struct jffs2_sb_info *c, break; #endif default: - if (ic->nodes == (void *)ic && ic->nlink == 0) + if (ic->nodes == (void *)ic && ic->pino_nlink == 0) jffs2_del_ino_cache(c, ic); } } diff --git a/fs/jffs2/fs.c b/fs/jffs2/fs.c index e14b185a80d..086c4383022 100644 --- a/fs/jffs2/fs.c +++ b/fs/jffs2/fs.c @@ -273,7 +273,7 @@ struct inode *jffs2_iget(struct super_block *sb, unsigned long ino) inode->i_mtime = ITIME(je32_to_cpu(latest_node.mtime)); inode->i_ctime = ITIME(je32_to_cpu(latest_node.ctime)); - inode->i_nlink = f->inocache->nlink; + inode->i_nlink = f->inocache->pino_nlink; inode->i_blocks = (inode->i_size + 511) >> 9; @@ -286,13 +286,12 @@ struct inode *jffs2_iget(struct super_block *sb, unsigned long ino) case S_IFDIR: { struct jffs2_full_dirent *fd; + inode->i_nlink = 2; /* parent and '.' */ for (fd=f->dents; fd; fd = fd->next) { if (fd->type == DT_DIR && fd->ino) inc_nlink(inode); } - /* and '..' */ - inc_nlink(inode); /* Root dir gets i_nlink 3 for some reason */ if (inode->i_ino == 1) inc_nlink(inode); diff --git a/fs/jffs2/gc.c b/fs/jffs2/gc.c index d4db0efecea..090c556ffed 100644 --- a/fs/jffs2/gc.c +++ b/fs/jffs2/gc.c @@ -161,8 +161,8 @@ int jffs2_garbage_collect_pass(struct jffs2_sb_info *c) continue; } - if (!ic->nlink) { - D1(printk(KERN_DEBUG "Skipping check of ino #%d with nlink zero\n", + if (!ic->pino_nlink) { + D1(printk(KERN_DEBUG "Skipping check of ino #%d with nlink/pino zero\n", ic->ino)); spin_unlock(&c->inocache_lock); jffs2_xattr_delete_inode(c, ic); @@ -398,7 +398,7 @@ int jffs2_garbage_collect_pass(struct jffs2_sb_info *c) it's vaguely possible. */ inum = ic->ino; - nlink = ic->nlink; + nlink = ic->pino_nlink; spin_unlock(&c->inocache_lock); f = jffs2_gc_fetch_inode(c, inum, !nlink); diff --git a/fs/jffs2/nodelist.h b/fs/jffs2/nodelist.h index 8219df6eb6d..1750445556c 100644 --- a/fs/jffs2/nodelist.h +++ b/fs/jffs2/nodelist.h @@ -177,7 +177,10 @@ struct jffs2_inode_cache { #ifdef CONFIG_JFFS2_FS_XATTR struct jffs2_xattr_ref *xref; #endif - int nlink; + uint32_t pino_nlink; /* Directories store parent inode + here; other inodes store nlink. + Zero always means that it's + completely unlinked. */ }; /* Inode states for 'state' above. We need the 'GC' state to prevent diff --git a/fs/jffs2/nodemgmt.c b/fs/jffs2/nodemgmt.c index 9df8f3ef20d..a9bf9603c1b 100644 --- a/fs/jffs2/nodemgmt.c +++ b/fs/jffs2/nodemgmt.c @@ -709,7 +709,7 @@ void jffs2_mark_node_obsolete(struct jffs2_sb_info *c, struct jffs2_raw_node_ref break; #endif default: - if (ic->nodes == (void *)ic && ic->nlink == 0) + if (ic->nodes == (void *)ic && ic->pino_nlink == 0) jffs2_del_ino_cache(c, ic); break; } diff --git a/fs/jffs2/readinode.c b/fs/jffs2/readinode.c index 4cb4d76de07..9fc4833c117 100644 --- a/fs/jffs2/readinode.c +++ b/fs/jffs2/readinode.c @@ -1123,7 +1123,8 @@ static int jffs2_do_read_inode_internal(struct jffs2_sb_info *c, size_t retlen; int ret; - dbg_readinode("ino #%u nlink is %d\n", f->inocache->ino, f->inocache->nlink); + dbg_readinode("ino #%u pino/nlink is %d\n", f->inocache->ino, + f->inocache->pino_nlink); memset(&rii, 0, sizeof(rii)); @@ -1358,7 +1359,7 @@ int jffs2_do_read_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f, } 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->ino = f->inocache->pino_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); @@ -1401,7 +1402,7 @@ void jffs2_do_clear_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f) jffs2_clear_acl(f); jffs2_xattr_delete_inode(c, f->inocache); mutex_lock(&f->sem); - deleted = f->inocache && !f->inocache->nlink; + deleted = f->inocache && !f->inocache->pino_nlink; if (f->inocache && f->inocache->state != INO_STATE_CHECKING) jffs2_set_inocache_state(c, f->inocache, INO_STATE_CLEARING); diff --git a/fs/jffs2/scan.c b/fs/jffs2/scan.c index 272872d27fd..8c1e692bef7 100644 --- a/fs/jffs2/scan.c +++ b/fs/jffs2/scan.c @@ -940,7 +940,7 @@ struct jffs2_inode_cache *jffs2_scan_make_ino_cache(struct jffs2_sb_info *c, uin ic->nodes = (void *)ic; jffs2_add_ino_cache(c, ic); if (ino == 1) - ic->nlink = 1; + ic->pino_nlink = 1; return ic; } diff --git a/fs/jffs2/wbuf.c b/fs/jffs2/wbuf.c index 92ab32a987b..0e78b00035e 100644 --- a/fs/jffs2/wbuf.c +++ b/fs/jffs2/wbuf.c @@ -494,7 +494,7 @@ static void jffs2_wbuf_recover(struct jffs2_sb_info *c) /* If it's an in-core inode, then we have to adjust any full_dirent or full_dnode structure to point to the new version instead of the old */ - f = jffs2_gc_fetch_inode(c, ic->ino, !ic->nlink); + f = jffs2_gc_fetch_inode(c, ic->ino, !ic->pino_nlink); if (IS_ERR(f)) { /* Should never happen; it _must_ be present */ JFFS2_ERROR("Failed to iget() ino #%u, err %ld\n", diff --git a/fs/jffs2/write.c b/fs/jffs2/write.c index 87891bdd791..ca29440e943 100644 --- a/fs/jffs2/write.c +++ b/fs/jffs2/write.c @@ -19,7 +19,8 @@ #include "compr.h" -int jffs2_do_new_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f, uint32_t mode, struct jffs2_raw_inode *ri) +int jffs2_do_new_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f, + uint32_t mode, struct jffs2_raw_inode *ri) { struct jffs2_inode_cache *ic; @@ -31,7 +32,7 @@ int jffs2_do_new_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f, uint memset(ic, 0, sizeof(*ic)); f->inocache = ic; - f->inocache->nlink = 1; + f->inocache->pino_nlink = 1; /* Will be overwritten shortly for directories */ f->inocache->nodes = (struct jffs2_raw_node_ref *)f->inocache; f->inocache->state = INO_STATE_PRESENT; @@ -635,9 +636,9 @@ int jffs2_do_unlink(struct jffs2_sb_info *c, struct jffs2_inode_info *dir_f, jffs2_mark_node_obsolete(c, fd->raw); jffs2_free_full_dirent(fd); } - } - - dead_f->inocache->nlink--; + dead_f->inocache->pino_nlink = 0; + } else + dead_f->inocache->pino_nlink--; /* NB: Caller must set inode nlink if appropriate */ mutex_unlock(&dead_f->sem); } diff --git a/fs/jffs2/xattr.c b/fs/jffs2/xattr.c index e48665984cb..05531f291bf 100644 --- a/fs/jffs2/xattr.c +++ b/fs/jffs2/xattr.c @@ -592,7 +592,7 @@ void jffs2_xattr_delete_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache When an inode with XATTR is removed, those XATTRs must be removed. */ struct jffs2_xattr_ref *ref, *_ref; - if (!ic || ic->nlink > 0) + if (!ic || ic->pino_nlink > 0) return; down_write(&c->xattr_sem); @@ -829,7 +829,7 @@ void jffs2_build_xattr_subsystem(struct jffs2_sb_info *c) ref->xd and ref->ic are not valid yet. */ xd = jffs2_find_xattr_datum(c, ref->xid); ic = jffs2_get_ino_cache(c, ref->ino); - if (!xd || !ic || !ic->nlink) { + if (!xd || !ic || !ic->pino_nlink) { dbg_xattr("xref(ino=%u, xid=%u, xseqno=%u) is orphan.\n", ref->ino, ref->xid, ref->xseqno); ref->xseqno |= XREF_DELETE_MARKER;