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, 666 insertions, 0 deletions

diff --git a/fs/afs/dir.c b/fs/afs/dir.c
new file mode 100644
index 000000000000..6682d6d7f294
--- /dev/null
+++ b/fs/afs/dir.c
@@ -0,0 +1,666 @@
+/* dir.c: AFS filesystem directory handling
+ *
+ * Copyright (C) 2002 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/fs.h>
+#include <linux/pagemap.h>
+#include <linux/smp_lock.h>
+#include "vnode.h"
+#include "volume.h"
+#include <rxrpc/call.h>
+#include "super.h"
+#include "internal.h"
+
+static struct dentry *afs_dir_lookup(struct inode *dir, struct dentry *dentry,
+                                     struct nameidata *nd);
+static int afs_dir_open(struct inode *inode, struct file *file);
+static int afs_dir_readdir(struct file *file, void *dirent, filldir_t filldir);
+static int afs_d_revalidate(struct dentry *dentry, struct nameidata *nd);
+static int afs_d_delete(struct dentry *dentry);
+static int afs_dir_lookup_filldir(void *_cookie, const char *name, int nlen,
+                                  loff_t fpos, ino_t ino, unsigned dtype);
+
+struct file_operations afs_dir_file_operations = {
+        .open           = afs_dir_open,
+        .readdir        = afs_dir_readdir,
+};
+
+struct inode_operations afs_dir_inode_operations = {
+        .lookup         = afs_dir_lookup,
+        .getattr        = afs_inode_getattr,
+#if 0 /* TODO */
+        .create         = afs_dir_create,
+        .link           = afs_dir_link,
+        .unlink         = afs_dir_unlink,
+        .symlink        = afs_dir_symlink,
+        .mkdir          = afs_dir_mkdir,
+        .rmdir          = afs_dir_rmdir,
+        .mknod          = afs_dir_mknod,
+        .rename         = afs_dir_rename,
+#endif
+};
+
+static struct dentry_operations afs_fs_dentry_operations = {
+        .d_revalidate   = afs_d_revalidate,
+        .d_delete       = afs_d_delete,
+};
+
+#define AFS_DIR_HASHTBL_SIZE    128
+#define AFS_DIR_DIRENT_SIZE     32
+#define AFS_DIRENT_PER_BLOCK    64
+
+union afs_dirent {
+        struct {
+                uint8_t         valid;
+                uint8_t         unused[1];
+                __be16          hash_next;
+                __be32          vnode;
+                __be32          unique;
+                uint8_t         name[16];
+                uint8_t         overflow[4];    /* if any char of the name (inc
+                                                 * NUL) reaches here, consume
+                                                 * the next dirent too */
+        } u;
+        uint8_t extended_name[32];
+};
+
+/* AFS directory page header (one at the beginning of every 2048-byte chunk) */
+struct afs_dir_pagehdr {
+        __be16          npages;
+        __be16          magic;
+#define AFS_DIR_MAGIC htons(1234)
+        uint8_t         nentries;
+        uint8_t         bitmap[8];
+        uint8_t         pad[19];
+};
+
+/* directory block layout */
+union afs_dir_block {
+
+        struct afs_dir_pagehdr pagehdr;
+
+        struct {
+                struct afs_dir_pagehdr  pagehdr;
+                uint8_t                 alloc_ctrs[128];
+                /* dir hash table */
+                uint16_t                hashtable[AFS_DIR_HASHTBL_SIZE];
+        } hdr;
+
+        union afs_dirent dirents[AFS_DIRENT_PER_BLOCK];
+};
+
+/* layout on a linux VM page */
+struct afs_dir_page {
+        union afs_dir_block blocks[PAGE_SIZE / sizeof(union afs_dir_block)];
+};
+
+struct afs_dir_lookup_cookie {
+        struct afs_fid  fid;
+        const char      *name;
+        size_t          nlen;
+        int             found;
+};
+
+/*****************************************************************************/
+/*
+ * check that a directory page is valid
+ */
+static inline void afs_dir_check_page(struct inode *dir, struct page *page)
+{
+        struct afs_dir_page *dbuf;
+        loff_t latter;
+        int tmp, qty;
+
+#if 0
+        /* check the page count */
+        qty = desc.size / sizeof(dbuf->blocks[0]);
+        if (qty == 0)
+                goto error;
+
+        if (page->index==0 && qty!=ntohs(dbuf->blocks[0].pagehdr.npages)) {
+                printk("kAFS: %s(%lu): wrong number of dir blocks %d!=%hu\n",
+                       __FUNCTION__,dir->i_ino,qty,ntohs(dbuf->blocks[0].pagehdr.npages));
+                goto error;
+        }
+#endif
+
+        /* determine how many magic numbers there should be in this page */
+        latter = dir->i_size - (page->index << PAGE_CACHE_SHIFT);
+        if (latter >= PAGE_SIZE)
+                qty = PAGE_SIZE;
+        else
+                qty = latter;
+        qty /= sizeof(union afs_dir_block);
+
+        /* check them */
+        dbuf = page_address(page);
+        for (tmp = 0; tmp < qty; tmp++) {
+                if (dbuf->blocks[tmp].pagehdr.magic != AFS_DIR_MAGIC) {
+                        printk("kAFS: %s(%lu): bad magic %d/%d is %04hx\n",
+                               __FUNCTION__, dir->i_ino, tmp, qty,
+                               ntohs(dbuf->blocks[tmp].pagehdr.magic));
+                        goto error;
+                }
+        }
+
+        SetPageChecked(page);
+        return;
+
+ error:
+        SetPageChecked(page);
+        SetPageError(page);
+
+} /* end afs_dir_check_page() */
+
+/*****************************************************************************/
+/*
+ * discard a page cached in the pagecache
+ */
+static inline void afs_dir_put_page(struct page *page)
+{
+        kunmap(page);
+        page_cache_release(page);
+
+} /* end afs_dir_put_page() */
+
+/*****************************************************************************/
+/*
+ * get a page into the pagecache
+ */
+static struct page *afs_dir_get_page(struct inode *dir, unsigned long index)
+{
+        struct page *page;
+
+        _enter("{%lu},%lu", dir->i_ino, index);
+
+        page = read_cache_page(dir->i_mapping,index,
+                               (filler_t *) dir->i_mapping->a_ops->readpage,
+                               NULL);
+        if (!IS_ERR(page)) {
+                wait_on_page_locked(page);
+                kmap(page);
+                if (!PageUptodate(page))
+                        goto fail;
+                if (!PageChecked(page))
+                        afs_dir_check_page(dir, page);
+                if (PageError(page))
+                        goto fail;
+        }
+        return page;
+
+ fail:
+        afs_dir_put_page(page);
+        return ERR_PTR(-EIO);
+} /* end afs_dir_get_page() */
+
+/*****************************************************************************/
+/*
+ * open an AFS directory file
+ */
+static int afs_dir_open(struct inode *inode, struct file *file)
+{
+        _enter("{%lu}", inode->i_ino);
+
+        BUG_ON(sizeof(union afs_dir_block) != 2048);
+        BUG_ON(sizeof(union afs_dirent) != 32);
+
+        if (AFS_FS_I(inode)->flags & AFS_VNODE_DELETED)
+                return -ENOENT;
+
+        _leave(" = 0");
+        return 0;
+
+} /* end afs_dir_open() */
+
+/*****************************************************************************/
+/*
+ * deal with one block in an AFS directory
+ */
+static int afs_dir_iterate_block(unsigned *fpos,
+                                 union afs_dir_block *block,
+                                 unsigned blkoff,
+                                 void *cookie,
+                                 filldir_t filldir)
+{
+        union afs_dirent *dire;
+        unsigned offset, next, curr;
+        size_t nlen;
+        int tmp, ret;
+
+        _enter("%u,%x,%p,,",*fpos,blkoff,block);
+
+        curr = (*fpos - blkoff) / sizeof(union afs_dirent);
+
+        /* walk through the block, an entry at a time */
+        for (offset = AFS_DIRENT_PER_BLOCK - block->pagehdr.nentries;
+             offset < AFS_DIRENT_PER_BLOCK;
+             offset = next
+             ) {
+                next = offset + 1;
+
+                /* skip entries marked unused in the bitmap */
+                if (!(block->pagehdr.bitmap[offset / 8] &
+                      (1 << (offset % 8)))) {
+                        _debug("ENT[%Zu.%u]: unused\n",
+                               blkoff / sizeof(union afs_dir_block), offset);
+                        if (offset >= curr)
+                                *fpos = blkoff +
+                                        next * sizeof(union afs_dirent);
+                        continue;
+                }
+
+                /* got a valid entry */
+                dire = &block->dirents[offset];
+                nlen = strnlen(dire->u.name,
+                               sizeof(*block) -
+                               offset * sizeof(union afs_dirent));
+
+                _debug("ENT[%Zu.%u]: %s %Zu \"%s\"\n",
+                       blkoff / sizeof(union afs_dir_block), offset,
+                       (offset < curr ? "skip" : "fill"),
+                       nlen, dire->u.name);
+
+                /* work out where the next possible entry is */
+                for (tmp = nlen; tmp > 15; tmp -= sizeof(union afs_dirent)) {
+                        if (next >= AFS_DIRENT_PER_BLOCK) {
+                                _debug("ENT[%Zu.%u]:"
+                                       " %u travelled beyond end dir block"
+                                       " (len %u/%Zu)\n",
+                                       blkoff / sizeof(union afs_dir_block),
+                                       offset, next, tmp, nlen);
+                                return -EIO;
+                        }
+                        if (!(block->pagehdr.bitmap[next / 8] &
+                              (1 << (next % 8)))) {
+                                _debug("ENT[%Zu.%u]:"
+                                       " %u unmarked extension (len %u/%Zu)\n",
+                                       blkoff / sizeof(union afs_dir_block),
+                                       offset, next, tmp, nlen);
+                                return -EIO;
+                        }
+
+                        _debug("ENT[%Zu.%u]: ext %u/%Zu\n",
+                               blkoff / sizeof(union afs_dir_block),
+                               next, tmp, nlen);
+                        next++;
+                }
+
+                /* skip if starts before the current position */
+                if (offset < curr)
+                        continue;
+
+                /* found the next entry */
+                ret = filldir(cookie,
+                              dire->u.name,
+                              nlen,
+                              blkoff + offset * sizeof(union afs_dirent),
+                              ntohl(dire->u.vnode),
+                              filldir == afs_dir_lookup_filldir ?
+                              ntohl(dire->u.unique) : DT_UNKNOWN);
+                if (ret < 0) {
+                        _leave(" = 0 [full]");
+                        return 0;
+                }
+
+                *fpos = blkoff + next * sizeof(union afs_dirent);
+        }
+
+        _leave(" = 1 [more]");
+        return 1;
+} /* end afs_dir_iterate_block() */
+
+/*****************************************************************************/
+/*
+ * read an AFS directory
+ */
+static int afs_dir_iterate(struct inode *dir, unsigned *fpos, void *cookie,
+                           filldir_t filldir)
+{
+        union afs_dir_block     *dblock;
+        struct afs_dir_page *dbuf;
+        struct page *page;
+        unsigned blkoff, limit;
+        int ret;
+
+        _enter("{%lu},%u,,", dir->i_ino, *fpos);
+
+        if (AFS_FS_I(dir)->flags & AFS_VNODE_DELETED) {
+                _leave(" = -ESTALE");
+                return -ESTALE;
+        }
+
+        /* round the file position up to the next entry boundary */
+        *fpos += sizeof(union afs_dirent) - 1;
+        *fpos &= ~(sizeof(union afs_dirent) - 1);
+
+        /* walk through the blocks in sequence */
+        ret = 0;
+        while (*fpos < dir->i_size) {
+                blkoff = *fpos & ~(sizeof(union afs_dir_block) - 1);
+
+                /* fetch the appropriate page from the directory */
+                page = afs_dir_get_page(dir, blkoff / PAGE_SIZE);
+                if (IS_ERR(page)) {
+                        ret = PTR_ERR(page);
+                        break;
+                }
+
+                limit = blkoff & ~(PAGE_SIZE - 1);
+
+                dbuf = page_address(page);
+
+                /* deal with the individual blocks stashed on this page */
+                do {
+                        dblock = &dbuf->blocks[(blkoff % PAGE_SIZE) /
+                                               sizeof(union afs_dir_block)];
+                        ret = afs_dir_iterate_block(fpos, dblock, blkoff,
+                                                    cookie, filldir);
+                        if (ret != 1) {
+                                afs_dir_put_page(page);
+                                goto out;
+                        }
+
+                        blkoff += sizeof(union afs_dir_block);
+
+                } while (*fpos < dir->i_size && blkoff < limit);
+
+                afs_dir_put_page(page);
+                ret = 0;
+        }
+
+ out:
+        _leave(" = %d", ret);
+        return ret;
+} /* end afs_dir_iterate() */
+
+/*****************************************************************************/
+/*
+ * read an AFS directory
+ */
+static int afs_dir_readdir(struct file *file, void *cookie, filldir_t filldir)
+{
+        unsigned fpos;
+        int ret;
+
+        _enter("{%Ld,{%lu}}", file->f_pos, file->f_dentry->d_inode->i_ino);
+
+        fpos = file->f_pos;
+        ret = afs_dir_iterate(file->f_dentry->d_inode, &fpos, cookie, filldir);
+        file->f_pos = fpos;
+
+        _leave(" = %d", ret);
+        return ret;
+} /* end afs_dir_readdir() */
+
+/*****************************************************************************/
+/*
+ * search the directory for a name
+ * - if afs_dir_iterate_block() spots this function, it'll pass the FID
+ *   uniquifier through dtype
+ */
+static int afs_dir_lookup_filldir(void *_cookie, const char *name, int nlen,
+                                  loff_t fpos, ino_t ino, unsigned dtype)
+{
+        struct afs_dir_lookup_cookie *cookie = _cookie;
+
+        _enter("{%s,%Zu},%s,%u,,%lu,%u",
+               cookie->name, cookie->nlen, name, nlen, ino, dtype);
+
+        if (cookie->nlen != nlen || memcmp(cookie->name, name, nlen) != 0) {
+                _leave(" = 0 [no]");
+                return 0;
+        }
+
+        cookie->fid.vnode = ino;
+        cookie->fid.unique = dtype;
+        cookie->found = 1;
+
+        _leave(" = -1 [found]");
+        return -1;
+} /* end afs_dir_lookup_filldir() */
+
+/*****************************************************************************/
+/*
+ * look up an entry in a directory
+ */
+static struct dentry *afs_dir_lookup(struct inode *dir, struct dentry *dentry,
+                                     struct nameidata *nd)
+{
+        struct afs_dir_lookup_cookie cookie;
+        struct afs_super_info *as;
+        struct afs_vnode *vnode;
+        struct inode *inode;
+        unsigned fpos;
+        int ret;
+
+        _enter("{%lu},%p{%s}", dir->i_ino, dentry, dentry->d_name.name);
+
+        /* insanity checks first */
+        BUG_ON(sizeof(union afs_dir_block) != 2048);
+        BUG_ON(sizeof(union afs_dirent) != 32);
+
+        if (dentry->d_name.len > 255) {
+                _leave(" = -ENAMETOOLONG");
+                return ERR_PTR(-ENAMETOOLONG);
+        }
+
+        vnode = AFS_FS_I(dir);
+        if (vnode->flags & AFS_VNODE_DELETED) {
+                _leave(" = -ESTALE");
+                return ERR_PTR(-ESTALE);
+        }
+
+        as = dir->i_sb->s_fs_info;
+
+        /* search the directory */
+        cookie.name     = dentry->d_name.name;
+        cookie.nlen     = dentry->d_name.len;
+        cookie.fid.vid  = as->volume->vid;
+        cookie.found    = 0;
+
+        fpos = 0;
+        ret = afs_dir_iterate(dir, &fpos, &cookie, afs_dir_lookup_filldir);
+        if (ret < 0) {
+                _leave(" = %d", ret);
+                return ERR_PTR(ret);
+        }
+
+        ret = -ENOENT;
+        if (!cookie.found) {
+                _leave(" = %d", ret);
+                return ERR_PTR(ret);
+        }
+
+        /* instantiate the dentry */
+        ret = afs_iget(dir->i_sb, &cookie.fid, &inode);
+        if (ret < 0) {
+                _leave(" = %d", ret);
+                return ERR_PTR(ret);
+        }
+
+        dentry->d_op = &afs_fs_dentry_operations;
+        dentry->d_fsdata = (void *) (unsigned long) vnode->status.version;
+
+        d_add(dentry, inode);
+        _leave(" = 0 { vn=%u u=%u } -> { ino=%lu v=%lu }",
+               cookie.fid.vnode,
+               cookie.fid.unique,
+               dentry->d_inode->i_ino,
+               dentry->d_inode->i_version);
+
+        return NULL;
+} /* end afs_dir_lookup() */
+
+/*****************************************************************************/
+/*
+ * check that a dentry lookup hit has found a valid entry
+ * - NOTE! the hit can be a negative hit too, so we can't assume we have an
+ *   inode
+ * (derived from nfs_lookup_revalidate)
+ */
+static int afs_d_revalidate(struct dentry *dentry, struct nameidata *nd)
+{
+        struct afs_dir_lookup_cookie cookie;
+        struct dentry *parent;
+        struct inode *inode, *dir;
+        unsigned fpos;
+        int ret;
+
+        _enter("{sb=%p n=%s},", dentry->d_sb, dentry->d_name.name);
+
+        /* lock down the parent dentry so we can peer at it */
+        parent = dget_parent(dentry->d_parent);
+
+        dir = parent->d_inode;
+        inode = dentry->d_inode;
+
+        /* handle a negative dentry */
+        if (!inode)
+                goto out_bad;
+
+        /* handle a bad inode */
+        if (is_bad_inode(inode)) {
+                printk("kAFS: afs_d_revalidate: %s/%s has bad inode\n",
+                       dentry->d_parent->d_name.name, dentry->d_name.name);
+                goto out_bad;
+        }
+
+        /* force a full look up if the parent directory changed since last the
+         * server was consulted
+         * - otherwise this inode must still exist, even if the inode details
+         *   themselves have changed
+         */
+        if (AFS_FS_I(dir)->flags & AFS_VNODE_CHANGED)
+                afs_vnode_fetch_status(AFS_FS_I(dir));
+
+        if (AFS_FS_I(dir)->flags & AFS_VNODE_DELETED) {
+                _debug("%s: parent dir deleted", dentry->d_name.name);
+                goto out_bad;
+        }
+
+        if (AFS_FS_I(inode)->flags & AFS_VNODE_DELETED) {
+                _debug("%s: file already deleted", dentry->d_name.name);
+                goto out_bad;
+        }
+
+        if ((unsigned long) dentry->d_fsdata !=
+            (unsigned long) AFS_FS_I(dir)->status.version) {
+                _debug("%s: parent changed %lu -> %u",
+                       dentry->d_name.name,
+                       (unsigned long) dentry->d_fsdata,
+                       (unsigned) AFS_FS_I(dir)->status.version);
+
+                /* search the directory for this vnode */
+                cookie.name     = dentry->d_name.name;
+                cookie.nlen     = dentry->d_name.len;
+                cookie.fid.vid  = AFS_FS_I(inode)->volume->vid;
+                cookie.found    = 0;
+
+                fpos = 0;
+                ret = afs_dir_iterate(dir, &fpos, &cookie,
+                                      afs_dir_lookup_filldir);
+                if (ret < 0) {
+                        _debug("failed to iterate dir %s: %d",
+                               parent->d_name.name, ret);
+                        goto out_bad;
+                }
+
+                if (!cookie.found) {
+                        _debug("%s: dirent not found", dentry->d_name.name);
+                        goto not_found;
+                }
+
+                /* if the vnode ID has changed, then the dirent points to a
+                 * different file */
+                if (cookie.fid.vnode != AFS_FS_I(inode)->fid.vnode) {
+                        _debug("%s: dirent changed", dentry->d_name.name);
+                        goto not_found;
+                }
+
+                /* if the vnode ID uniqifier has changed, then the file has
+                 * been deleted */
+                if (cookie.fid.unique != AFS_FS_I(inode)->fid.unique) {
+                        _debug("%s: file deleted (uq %u -> %u I:%lu)",
+                               dentry->d_name.name,
+                               cookie.fid.unique,
+                               AFS_FS_I(inode)->fid.unique,
+                               inode->i_version);
+                        spin_lock(&AFS_FS_I(inode)->lock);
+                        AFS_FS_I(inode)->flags |= AFS_VNODE_DELETED;
+                        spin_unlock(&AFS_FS_I(inode)->lock);
+                        invalidate_remote_inode(inode);
+                        goto out_bad;
+                }
+
+                dentry->d_fsdata =
+                        (void *) (unsigned long) AFS_FS_I(dir)->status.version;
+        }
+
+ out_valid:
+        dput(parent);
+        _leave(" = 1 [valid]");
+        return 1;
+
+        /* the dirent, if it exists, now points to a different vnode */
+ not_found:
+        spin_lock(&dentry->d_lock);
+        dentry->d_flags |= DCACHE_NFSFS_RENAMED;
+        spin_unlock(&dentry->d_lock);
+
+ out_bad:
+        if (inode) {
+                /* don't unhash if we have submounts */
+                if (have_submounts(dentry))
+                        goto out_valid;
+        }
+
+        shrink_dcache_parent(dentry);
+
+        _debug("dropping dentry %s/%s",
+               dentry->d_parent->d_name.name, dentry->d_name.name);
+        d_drop(dentry);
+
+        dput(parent);
+
+        _leave(" = 0 [bad]");
+        return 0;
+} /* end afs_d_revalidate() */
+
+/*****************************************************************************/
+/*
+ * allow the VFS to enquire as to whether a dentry should be unhashed (mustn't
+ * sleep)
+ * - called from dput() when d_count is going to 0.
+ * - return 1 to request dentry be unhashed, 0 otherwise
+ */
+static int afs_d_delete(struct dentry *dentry)
+{
+        _enter("%s", dentry->d_name.name);
+
+        if (dentry->d_flags & DCACHE_NFSFS_RENAMED)
+                goto zap;
+
+        if (dentry->d_inode) {
+                if (AFS_FS_I(dentry->d_inode)->flags & AFS_VNODE_DELETED)
+                        goto zap;
+        }
+
+        _leave(" = 0 [keep]");
+        return 0;
+
+ zap:
+        _leave(" = 1 [zap]");
+        return 1;
+} /* end afs_d_delete() */