[JFFS2] Improve getdents vs. f_pos handling on NOR flash.

Commit a491486a20 started obliterating
dirents directly on the medium, when jffs2_can_mark_obsolete(). Removing
them immediately from the f->dents list, however, screws up handling of
f_pos within a directory -- because the offset is equivalent to the
number of entries through the list we are, and the existence of
deletion dirents served to provide 'placeholders' for unlinked
entries. Now, 'rm -r' doesn't even manage to unlink everything in the
directory.

Revert to keeping 'deletion' dirents in the list, at least in memory
even though we no longer write anything to the medium.

Spotted, debugged and mostly fixed by Joakim Tjernlund

Signed-off-by: David Woodhouse <dwmw2@infradead.org>
This commit is contained in:
David Woodhouse 2007-11-01 16:25:56 -04:00
parent d10a39d1a5
commit 15953580e7
2 changed files with 21 additions and 15 deletions

View File

@ -32,14 +32,17 @@ void jffs2_add_fd_to_list(struct jffs2_sb_info *c, struct jffs2_full_dirent *new
if ((*prev)->nhash == new->nhash && !strcmp((*prev)->name, new->name)) { if ((*prev)->nhash == new->nhash && !strcmp((*prev)->name, new->name)) {
/* Duplicate. Free one */ /* Duplicate. Free one */
if (new->version < (*prev)->version) { if (new->version < (*prev)->version) {
dbg_dentlist("Eep! Marking new dirent node is obsolete, old is \"%s\", ino #%u\n", dbg_dentlist("Eep! Marking new dirent node obsolete, old is \"%s\", ino #%u\n",
(*prev)->name, (*prev)->ino); (*prev)->name, (*prev)->ino);
jffs2_mark_node_obsolete(c, new->raw); jffs2_mark_node_obsolete(c, new->raw);
jffs2_free_full_dirent(new); jffs2_free_full_dirent(new);
} else { } else {
dbg_dentlist("marking old dirent \"%s\", ino #%u bsolete\n", dbg_dentlist("marking old dirent \"%s\", ino #%u obsolete\n",
(*prev)->name, (*prev)->ino); (*prev)->name, (*prev)->ino);
new->next = (*prev)->next; new->next = (*prev)->next;
/* It may have been a 'placeholder' deletion dirent,
if jffs2_can_mark_obsolete() (see jffs2_do_unlink()) */
if ((*prev)->raw)
jffs2_mark_node_obsolete(c, ((*prev)->raw)); jffs2_mark_node_obsolete(c, ((*prev)->raw));
jffs2_free_full_dirent(*prev); jffs2_free_full_dirent(*prev);
*prev = new; *prev = new;

View File

@ -582,7 +582,7 @@ int jffs2_do_unlink(struct jffs2_sb_info *c, struct jffs2_inode_info *dir_f,
jffs2_add_fd_to_list(c, fd, &dir_f->dents); jffs2_add_fd_to_list(c, fd, &dir_f->dents);
up(&dir_f->sem); up(&dir_f->sem);
} else { } else {
struct jffs2_full_dirent **prev = &dir_f->dents; struct jffs2_full_dirent *fd = dir_f->dents;
uint32_t nhash = full_name_hash(name, namelen); uint32_t nhash = full_name_hash(name, namelen);
/* We don't actually want to reserve any space, but we do /* We don't actually want to reserve any space, but we do
@ -590,18 +590,20 @@ int jffs2_do_unlink(struct jffs2_sb_info *c, struct jffs2_inode_info *dir_f,
down(&c->alloc_sem); down(&c->alloc_sem);
down(&dir_f->sem); down(&dir_f->sem);
while ((*prev) && (*prev)->nhash <= nhash) { for (fd = dir_f->dents; fd; fd = fd->next) {
if ((*prev)->nhash == nhash && if (fd->nhash == nhash &&
!memcmp((*prev)->name, name, namelen) && !memcmp(fd->name, name, namelen) &&
!(*prev)->name[namelen]) { !fd->name[namelen]) {
struct jffs2_full_dirent *this = *prev;
D1(printk(KERN_DEBUG "Marking old dirent node (ino #%u) @%08x obsolete\n", D1(printk(KERN_DEBUG "Marking old dirent node (ino #%u) @%08x obsolete\n",
this->ino, ref_offset(this->raw))); fd->ino, ref_offset(fd->raw)));
jffs2_mark_node_obsolete(c, fd->raw);
*prev = this->next; /* We don't want to remove it from the list immediately,
jffs2_mark_node_obsolete(c, (this->raw)); because that screws up getdents()/seek() semantics even
jffs2_free_full_dirent(this); more than they're screwed already. Turn it into a
node-less deletion dirent instead -- a placeholder */
fd->raw = NULL;
fd->ino = 0;
break; break;
} }
prev = &((*prev)->next); prev = &((*prev)->next);
@ -630,6 +632,7 @@ int jffs2_do_unlink(struct jffs2_sb_info *c, struct jffs2_inode_info *dir_f,
D1(printk(KERN_DEBUG "Removing deletion dirent for \"%s\" from dir ino #%u\n", D1(printk(KERN_DEBUG "Removing deletion dirent for \"%s\" from dir ino #%u\n",
fd->name, dead_f->inocache->ino)); fd->name, dead_f->inocache->ino));
} }
if (fd->raw)
jffs2_mark_node_obsolete(c, fd->raw); jffs2_mark_node_obsolete(c, fd->raw);
jffs2_free_full_dirent(fd); jffs2_free_full_dirent(fd);
} }