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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /fs/afs/dir.c
Initial import
Diffstat (limited to 'fs/afs/dir.c')
-rw-r--r--fs/afs/dir.c1123
1 files changed, 1123 insertions, 0 deletions
diff --git a/fs/afs/dir.c b/fs/afs/dir.c
new file mode 100644
index 000000000..e10e17788
--- /dev/null
+++ b/fs/afs/dir.c
@@ -0,0 +1,1123 @@
+/* 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/fs.h>
+#include <linux/namei.h>
+#include <linux/pagemap.h>
+#include <linux/ctype.h>
+#include <linux/sched.h>
+#include "internal.h"
+
+static struct dentry *afs_lookup(struct inode *dir, struct dentry *dentry,
+ unsigned int flags);
+static int afs_dir_open(struct inode *inode, struct file *file);
+static int afs_readdir(struct file *file, struct dir_context *ctx);
+static int afs_d_revalidate(struct dentry *dentry, unsigned int flags);
+static int afs_d_delete(const struct dentry *dentry);
+static void afs_d_release(struct dentry *dentry);
+static int afs_lookup_filldir(struct dir_context *ctx, const char *name, int nlen,
+ loff_t fpos, u64 ino, unsigned dtype);
+static int afs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
+ bool excl);
+static int afs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode);
+static int afs_rmdir(struct inode *dir, struct dentry *dentry);
+static int afs_unlink(struct inode *dir, struct dentry *dentry);
+static int afs_link(struct dentry *from, struct inode *dir,
+ struct dentry *dentry);
+static int afs_symlink(struct inode *dir, struct dentry *dentry,
+ const char *content);
+static int afs_rename(struct inode *old_dir, struct dentry *old_dentry,
+ struct inode *new_dir, struct dentry *new_dentry);
+
+const struct file_operations afs_dir_file_operations = {
+ .open = afs_dir_open,
+ .release = afs_release,
+ .iterate = afs_readdir,
+ .lock = afs_lock,
+ .llseek = generic_file_llseek,
+};
+
+const struct inode_operations afs_dir_inode_operations = {
+ .create = afs_create,
+ .lookup = afs_lookup,
+ .link = afs_link,
+ .unlink = afs_unlink,
+ .symlink = afs_symlink,
+ .mkdir = afs_mkdir,
+ .rmdir = afs_rmdir,
+ .rename = afs_rename,
+ .permission = afs_permission,
+ .getattr = afs_getattr,
+ .setattr = afs_setattr,
+};
+
+const struct dentry_operations afs_fs_dentry_operations = {
+ .d_revalidate = afs_d_revalidate,
+ .d_delete = afs_d_delete,
+ .d_release = afs_d_release,
+ .d_automount = afs_d_automount,
+};
+
+#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_lookup_cookie {
+ struct dir_context ctx;
+ struct afs_fid fid;
+ struct qstr name;
+ 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",
+ __func__, 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_offset(page);
+ 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",
+ __func__, dir->i_ino, tmp, qty,
+ ntohs(dbuf->blocks[tmp].pagehdr.magic));
+ goto error;
+ }
+ }
+
+ SetPageChecked(page);
+ return;
+
+error:
+ SetPageChecked(page);
+ SetPageError(page);
+}
+
+/*
+ * discard a page cached in the pagecache
+ */
+static inline void afs_dir_put_page(struct page *page)
+{
+ kunmap(page);
+ page_cache_release(page);
+}
+
+/*
+ * get a page into the pagecache
+ */
+static struct page *afs_dir_get_page(struct inode *dir, unsigned long index,
+ struct key *key)
+{
+ struct page *page;
+ _enter("{%lu},%lu", dir->i_ino, index);
+
+ page = read_cache_page(dir->i_mapping, index, afs_page_filler, key);
+ if (!IS_ERR(page)) {
+ kmap(page);
+ if (!PageChecked(page))
+ afs_dir_check_page(dir, page);
+ if (PageError(page))
+ goto fail;
+ }
+ return page;
+
+fail:
+ afs_dir_put_page(page);
+ _leave(" = -EIO");
+ return ERR_PTR(-EIO);
+}
+
+/*
+ * open an AFS directory file
+ */
+static int afs_dir_open(struct inode *inode, struct file *file)
+{
+ _enter("{%lu}", inode->i_ino);
+
+ BUILD_BUG_ON(sizeof(union afs_dir_block) != 2048);
+ BUILD_BUG_ON(sizeof(union afs_dirent) != 32);
+
+ if (test_bit(AFS_VNODE_DELETED, &AFS_FS_I(inode)->flags))
+ return -ENOENT;
+
+ return afs_open(inode, file);
+}
+
+/*
+ * deal with one block in an AFS directory
+ */
+static int afs_dir_iterate_block(struct dir_context *ctx,
+ union afs_dir_block *block,
+ unsigned blkoff)
+{
+ union afs_dirent *dire;
+ unsigned offset, next, curr;
+ size_t nlen;
+ int tmp;
+
+ _enter("%u,%x,%p,,",(unsigned)ctx->pos,blkoff,block);
+
+ curr = (ctx->pos - 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",
+ blkoff / sizeof(union afs_dir_block), offset);
+ if (offset >= curr)
+ ctx->pos = 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\"",
+ 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)",
+ 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)",
+ blkoff / sizeof(union afs_dir_block),
+ offset, next, tmp, nlen);
+ return -EIO;
+ }
+
+ _debug("ENT[%Zu.%u]: ext %u/%Zu",
+ 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 */
+ if (!dir_emit(ctx, dire->u.name, nlen,
+ ntohl(dire->u.vnode),
+ ctx->actor == afs_lookup_filldir ?
+ ntohl(dire->u.unique) : DT_UNKNOWN)) {
+ _leave(" = 0 [full]");
+ return 0;
+ }
+
+ ctx->pos = blkoff + next * sizeof(union afs_dirent);
+ }
+
+ _leave(" = 1 [more]");
+ return 1;
+}
+
+/*
+ * iterate through the data blob that lists the contents of an AFS directory
+ */
+static int afs_dir_iterate(struct inode *dir, struct dir_context *ctx,
+ struct key *key)
+{
+ union afs_dir_block *dblock;
+ struct afs_dir_page *dbuf;
+ struct page *page;
+ unsigned blkoff, limit;
+ int ret;
+
+ _enter("{%lu},%u,,", dir->i_ino, (unsigned)ctx->pos);
+
+ if (test_bit(AFS_VNODE_DELETED, &AFS_FS_I(dir)->flags)) {
+ _leave(" = -ESTALE");
+ return -ESTALE;
+ }
+
+ /* round the file position up to the next entry boundary */
+ ctx->pos += sizeof(union afs_dirent) - 1;
+ ctx->pos &= ~(sizeof(union afs_dirent) - 1);
+
+ /* walk through the blocks in sequence */
+ ret = 0;
+ while (ctx->pos < dir->i_size) {
+ blkoff = ctx->pos & ~(sizeof(union afs_dir_block) - 1);
+
+ /* fetch the appropriate page from the directory */
+ page = afs_dir_get_page(dir, blkoff / PAGE_SIZE, key);
+ 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(ctx, dblock, blkoff);
+ if (ret != 1) {
+ afs_dir_put_page(page);
+ goto out;
+ }
+
+ blkoff += sizeof(union afs_dir_block);
+
+ } while (ctx->pos < dir->i_size && blkoff < limit);
+
+ afs_dir_put_page(page);
+ ret = 0;
+ }
+
+out:
+ _leave(" = %d", ret);
+ return ret;
+}
+
+/*
+ * read an AFS directory
+ */
+static int afs_readdir(struct file *file, struct dir_context *ctx)
+{
+ return afs_dir_iterate(file_inode(file),
+ ctx, file->private_data);
+}
+
+/*
+ * 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_lookup_filldir(struct dir_context *ctx, const char *name,
+ int nlen, loff_t fpos, u64 ino, unsigned dtype)
+{
+ struct afs_lookup_cookie *cookie =
+ container_of(ctx, struct afs_lookup_cookie, ctx);
+
+ _enter("{%s,%u},%s,%u,,%llu,%u",
+ cookie->name.name, cookie->name.len, name, nlen,
+ (unsigned long long) ino, dtype);
+
+ /* insanity checks first */
+ BUILD_BUG_ON(sizeof(union afs_dir_block) != 2048);
+ BUILD_BUG_ON(sizeof(union afs_dirent) != 32);
+
+ if (cookie->name.len != nlen ||
+ memcmp(cookie->name.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;
+}
+
+/*
+ * do a lookup in a directory
+ * - just returns the FID the dentry name maps to if found
+ */
+static int afs_do_lookup(struct inode *dir, struct dentry *dentry,
+ struct afs_fid *fid, struct key *key)
+{
+ struct afs_super_info *as = dir->i_sb->s_fs_info;
+ struct afs_lookup_cookie cookie = {
+ .ctx.actor = afs_lookup_filldir,
+ .name = dentry->d_name,
+ .fid.vid = as->volume->vid
+ };
+ int ret;
+
+ _enter("{%lu},%p{%pd},", dir->i_ino, dentry, dentry);
+
+ /* search the directory */
+ ret = afs_dir_iterate(dir, &cookie.ctx, key);
+ if (ret < 0) {
+ _leave(" = %d [iter]", ret);
+ return ret;
+ }
+
+ ret = -ENOENT;
+ if (!cookie.found) {
+ _leave(" = -ENOENT [not found]");
+ return -ENOENT;
+ }
+
+ *fid = cookie.fid;
+ _leave(" = 0 { vn=%u u=%u }", fid->vnode, fid->unique);
+ return 0;
+}
+
+/*
+ * Try to auto mount the mountpoint with pseudo directory, if the autocell
+ * operation is setted.
+ */
+static struct inode *afs_try_auto_mntpt(
+ int ret, struct dentry *dentry, struct inode *dir, struct key *key,
+ struct afs_fid *fid)
+{
+ const char *devname = dentry->d_name.name;
+ struct afs_vnode *vnode = AFS_FS_I(dir);
+ struct inode *inode;
+
+ _enter("%d, %p{%pd}, {%x:%u}, %p",
+ ret, dentry, dentry, vnode->fid.vid, vnode->fid.vnode, key);
+
+ if (ret != -ENOENT ||
+ !test_bit(AFS_VNODE_AUTOCELL, &vnode->flags))
+ goto out;
+
+ inode = afs_iget_autocell(dir, devname, strlen(devname), key);
+ if (IS_ERR(inode)) {
+ ret = PTR_ERR(inode);
+ goto out;
+ }
+
+ *fid = AFS_FS_I(inode)->fid;
+ _leave("= %p", inode);
+ return inode;
+
+out:
+ _leave("= %d", ret);
+ return ERR_PTR(ret);
+}
+
+/*
+ * look up an entry in a directory
+ */
+static struct dentry *afs_lookup(struct inode *dir, struct dentry *dentry,
+ unsigned int flags)
+{
+ struct afs_vnode *vnode;
+ struct afs_fid fid;
+ struct inode *inode;
+ struct key *key;
+ int ret;
+
+ vnode = AFS_FS_I(dir);
+
+ _enter("{%x:%u},%p{%pd},",
+ vnode->fid.vid, vnode->fid.vnode, dentry, dentry);
+
+ ASSERTCMP(d_inode(dentry), ==, NULL);
+
+ if (dentry->d_name.len >= AFSNAMEMAX) {
+ _leave(" = -ENAMETOOLONG");
+ return ERR_PTR(-ENAMETOOLONG);
+ }
+
+ if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) {
+ _leave(" = -ESTALE");
+ return ERR_PTR(-ESTALE);
+ }
+
+ key = afs_request_key(vnode->volume->cell);
+ if (IS_ERR(key)) {
+ _leave(" = %ld [key]", PTR_ERR(key));
+ return ERR_CAST(key);
+ }
+
+ ret = afs_validate(vnode, key);
+ if (ret < 0) {
+ key_put(key);
+ _leave(" = %d [val]", ret);
+ return ERR_PTR(ret);
+ }
+
+ ret = afs_do_lookup(dir, dentry, &fid, key);
+ if (ret < 0) {
+ inode = afs_try_auto_mntpt(ret, dentry, dir, key, &fid);
+ if (!IS_ERR(inode)) {
+ key_put(key);
+ goto success;
+ }
+
+ ret = PTR_ERR(inode);
+ key_put(key);
+ if (ret == -ENOENT) {
+ d_add(dentry, NULL);
+ _leave(" = NULL [negative]");
+ return NULL;
+ }
+ _leave(" = %d [do]", ret);
+ return ERR_PTR(ret);
+ }
+ dentry->d_fsdata = (void *)(unsigned long) vnode->status.data_version;
+
+ /* instantiate the dentry */
+ inode = afs_iget(dir->i_sb, key, &fid, NULL, NULL);
+ key_put(key);
+ if (IS_ERR(inode)) {
+ _leave(" = %ld", PTR_ERR(inode));
+ return ERR_CAST(inode);
+ }
+
+success:
+ d_add(dentry, inode);
+ _leave(" = 0 { vn=%u u=%u } -> { ino=%lu v=%u }",
+ fid.vnode,
+ fid.unique,
+ d_inode(dentry)->i_ino,
+ d_inode(dentry)->i_generation);
+
+ return NULL;
+}
+
+/*
+ * 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
+ */
+static int afs_d_revalidate(struct dentry *dentry, unsigned int flags)
+{
+ struct afs_vnode *vnode, *dir;
+ struct afs_fid uninitialized_var(fid);
+ struct dentry *parent;
+ struct key *key;
+ void *dir_version;
+ int ret;
+
+ if (flags & LOOKUP_RCU)
+ return -ECHILD;
+
+ vnode = AFS_FS_I(d_inode(dentry));
+
+ if (d_really_is_positive(dentry))
+ _enter("{v={%x:%u} n=%pd fl=%lx},",
+ vnode->fid.vid, vnode->fid.vnode, dentry,
+ vnode->flags);
+ else
+ _enter("{neg n=%pd}", dentry);
+
+ key = afs_request_key(AFS_FS_S(dentry->d_sb)->volume->cell);
+ if (IS_ERR(key))
+ key = NULL;
+
+ /* lock down the parent dentry so we can peer at it */
+ parent = dget_parent(dentry);
+ dir = AFS_FS_I(d_inode(parent));
+
+ /* validate the parent directory */
+ if (test_bit(AFS_VNODE_MODIFIED, &dir->flags))
+ afs_validate(dir, key);
+
+ if (test_bit(AFS_VNODE_DELETED, &dir->flags)) {
+ _debug("%pd: parent dir deleted", dentry);
+ goto out_bad;
+ }
+
+ dir_version = (void *) (unsigned long) dir->status.data_version;
+ if (dentry->d_fsdata == dir_version)
+ goto out_valid; /* the dir contents are unchanged */
+
+ _debug("dir modified");
+
+ /* search the directory for this vnode */
+ ret = afs_do_lookup(&dir->vfs_inode, dentry, &fid, key);
+ switch (ret) {
+ case 0:
+ /* the filename maps to something */
+ if (d_really_is_negative(dentry))
+ goto out_bad;
+ if (is_bad_inode(d_inode(dentry))) {
+ printk("kAFS: afs_d_revalidate: %pd2 has bad inode\n",
+ dentry);
+ goto out_bad;
+ }
+
+ /* if the vnode ID has changed, then the dirent points to a
+ * different file */
+ if (fid.vnode != vnode->fid.vnode) {
+ _debug("%pd: dirent changed [%u != %u]",
+ dentry, fid.vnode,
+ vnode->fid.vnode);
+ goto not_found;
+ }
+
+ /* if the vnode ID uniqifier has changed, then the file has
+ * been deleted and replaced, and the original vnode ID has
+ * been reused */
+ if (fid.unique != vnode->fid.unique) {
+ _debug("%pd: file deleted (uq %u -> %u I:%u)",
+ dentry, fid.unique,
+ vnode->fid.unique,
+ d_inode(dentry)->i_generation);
+ spin_lock(&vnode->lock);
+ set_bit(AFS_VNODE_DELETED, &vnode->flags);
+ spin_unlock(&vnode->lock);
+ goto not_found;
+ }
+ goto out_valid;
+
+ case -ENOENT:
+ /* the filename is unknown */
+ _debug("%pd: dirent not found", dentry);
+ if (d_really_is_positive(dentry))
+ goto not_found;
+ goto out_valid;
+
+ default:
+ _debug("failed to iterate dir %pd: %d",
+ parent, ret);
+ goto out_bad;
+ }
+
+out_valid:
+ dentry->d_fsdata = dir_version;
+ dput(parent);
+ key_put(key);
+ _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:
+ _debug("dropping dentry %pd2", dentry);
+ dput(parent);
+ key_put(key);
+
+ _leave(" = 0 [bad]");
+ return 0;
+}
+
+/*
+ * 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(const struct dentry *dentry)
+{
+ _enter("%pd", dentry);
+
+ if (dentry->d_flags & DCACHE_NFSFS_RENAMED)
+ goto zap;
+
+ if (d_really_is_positive(dentry) &&
+ (test_bit(AFS_VNODE_DELETED, &AFS_FS_I(d_inode(dentry))->flags) ||
+ test_bit(AFS_VNODE_PSEUDODIR, &AFS_FS_I(d_inode(dentry))->flags)))
+ goto zap;
+
+ _leave(" = 0 [keep]");
+ return 0;
+
+zap:
+ _leave(" = 1 [zap]");
+ return 1;
+}
+
+/*
+ * handle dentry release
+ */
+static void afs_d_release(struct dentry *dentry)
+{
+ _enter("%pd", dentry);
+}
+
+/*
+ * create a directory on an AFS filesystem
+ */
+static int afs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+{
+ struct afs_file_status status;
+ struct afs_callback cb;
+ struct afs_server *server;
+ struct afs_vnode *dvnode, *vnode;
+ struct afs_fid fid;
+ struct inode *inode;
+ struct key *key;
+ int ret;
+
+ dvnode = AFS_FS_I(dir);
+
+ _enter("{%x:%u},{%pd},%ho",
+ dvnode->fid.vid, dvnode->fid.vnode, dentry, mode);
+
+ key = afs_request_key(dvnode->volume->cell);
+ if (IS_ERR(key)) {
+ ret = PTR_ERR(key);
+ goto error;
+ }
+
+ mode |= S_IFDIR;
+ ret = afs_vnode_create(dvnode, key, dentry->d_name.name,
+ mode, &fid, &status, &cb, &server);
+ if (ret < 0)
+ goto mkdir_error;
+
+ inode = afs_iget(dir->i_sb, key, &fid, &status, &cb);
+ if (IS_ERR(inode)) {
+ /* ENOMEM at a really inconvenient time - just abandon the new
+ * directory on the server */
+ ret = PTR_ERR(inode);
+ goto iget_error;
+ }
+
+ /* apply the status report we've got for the new vnode */
+ vnode = AFS_FS_I(inode);
+ spin_lock(&vnode->lock);
+ vnode->update_cnt++;
+ spin_unlock(&vnode->lock);
+ afs_vnode_finalise_status_update(vnode, server);
+ afs_put_server(server);
+
+ d_instantiate(dentry, inode);
+ if (d_unhashed(dentry)) {
+ _debug("not hashed");
+ d_rehash(dentry);
+ }
+ key_put(key);
+ _leave(" = 0");
+ return 0;
+
+iget_error:
+ afs_put_server(server);
+mkdir_error:
+ key_put(key);
+error:
+ d_drop(dentry);
+ _leave(" = %d", ret);
+ return ret;
+}
+
+/*
+ * remove a directory from an AFS filesystem
+ */
+static int afs_rmdir(struct inode *dir, struct dentry *dentry)
+{
+ struct afs_vnode *dvnode, *vnode;
+ struct key *key;
+ int ret;
+
+ dvnode = AFS_FS_I(dir);
+
+ _enter("{%x:%u},{%pd}",
+ dvnode->fid.vid, dvnode->fid.vnode, dentry);
+
+ key = afs_request_key(dvnode->volume->cell);
+ if (IS_ERR(key)) {
+ ret = PTR_ERR(key);
+ goto error;
+ }
+
+ ret = afs_vnode_remove(dvnode, key, dentry->d_name.name, true);
+ if (ret < 0)
+ goto rmdir_error;
+
+ if (d_really_is_positive(dentry)) {
+ vnode = AFS_FS_I(d_inode(dentry));
+ clear_nlink(&vnode->vfs_inode);
+ set_bit(AFS_VNODE_DELETED, &vnode->flags);
+ afs_discard_callback_on_delete(vnode);
+ }
+
+ key_put(key);
+ _leave(" = 0");
+ return 0;
+
+rmdir_error:
+ key_put(key);
+error:
+ _leave(" = %d", ret);
+ return ret;
+}
+
+/*
+ * remove a file from an AFS filesystem
+ */
+static int afs_unlink(struct inode *dir, struct dentry *dentry)
+{
+ struct afs_vnode *dvnode, *vnode;
+ struct key *key;
+ int ret;
+
+ dvnode = AFS_FS_I(dir);
+
+ _enter("{%x:%u},{%pd}",
+ dvnode->fid.vid, dvnode->fid.vnode, dentry);
+
+ ret = -ENAMETOOLONG;
+ if (dentry->d_name.len >= AFSNAMEMAX)
+ goto error;
+
+ key = afs_request_key(dvnode->volume->cell);
+ if (IS_ERR(key)) {
+ ret = PTR_ERR(key);
+ goto error;
+ }
+
+ if (d_really_is_positive(dentry)) {
+ vnode = AFS_FS_I(d_inode(dentry));
+
+ /* make sure we have a callback promise on the victim */
+ ret = afs_validate(vnode, key);
+ if (ret < 0)
+ goto error;
+ }
+
+ ret = afs_vnode_remove(dvnode, key, dentry->d_name.name, false);
+ if (ret < 0)
+ goto remove_error;
+
+ if (d_really_is_positive(dentry)) {
+ /* if the file wasn't deleted due to excess hard links, the
+ * fileserver will break the callback promise on the file - if
+ * it had one - before it returns to us, and if it was deleted,
+ * it won't
+ *
+ * however, if we didn't have a callback promise outstanding,
+ * or it was outstanding on a different server, then it won't
+ * break it either...
+ */
+ vnode = AFS_FS_I(d_inode(dentry));
+ if (test_bit(AFS_VNODE_DELETED, &vnode->flags))
+ _debug("AFS_VNODE_DELETED");
+ if (test_bit(AFS_VNODE_CB_BROKEN, &vnode->flags))
+ _debug("AFS_VNODE_CB_BROKEN");
+ set_bit(AFS_VNODE_CB_BROKEN, &vnode->flags);
+ ret = afs_validate(vnode, key);
+ _debug("nlink %d [val %d]", vnode->vfs_inode.i_nlink, ret);
+ }
+
+ key_put(key);
+ _leave(" = 0");
+ return 0;
+
+remove_error:
+ key_put(key);
+error:
+ _leave(" = %d", ret);
+ return ret;
+}
+
+/*
+ * create a regular file on an AFS filesystem
+ */
+static int afs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
+ bool excl)
+{
+ struct afs_file_status status;
+ struct afs_callback cb;
+ struct afs_server *server;
+ struct afs_vnode *dvnode, *vnode;
+ struct afs_fid fid;
+ struct inode *inode;
+ struct key *key;
+ int ret;
+
+ dvnode = AFS_FS_I(dir);
+
+ _enter("{%x:%u},{%pd},%ho,",
+ dvnode->fid.vid, dvnode->fid.vnode, dentry, mode);
+
+ key = afs_request_key(dvnode->volume->cell);
+ if (IS_ERR(key)) {
+ ret = PTR_ERR(key);
+ goto error;
+ }
+
+ mode |= S_IFREG;
+ ret = afs_vnode_create(dvnode, key, dentry->d_name.name,
+ mode, &fid, &status, &cb, &server);
+ if (ret < 0)
+ goto create_error;
+
+ inode = afs_iget(dir->i_sb, key, &fid, &status, &cb);
+ if (IS_ERR(inode)) {
+ /* ENOMEM at a really inconvenient time - just abandon the new
+ * directory on the server */
+ ret = PTR_ERR(inode);
+ goto iget_error;
+ }
+
+ /* apply the status report we've got for the new vnode */
+ vnode = AFS_FS_I(inode);
+ spin_lock(&vnode->lock);
+ vnode->update_cnt++;
+ spin_unlock(&vnode->lock);
+ afs_vnode_finalise_status_update(vnode, server);
+ afs_put_server(server);
+
+ d_instantiate(dentry, inode);
+ if (d_unhashed(dentry)) {
+ _debug("not hashed");
+ d_rehash(dentry);
+ }
+ key_put(key);
+ _leave(" = 0");
+ return 0;
+
+iget_error:
+ afs_put_server(server);
+create_error:
+ key_put(key);
+error:
+ d_drop(dentry);
+ _leave(" = %d", ret);
+ return ret;
+}
+
+/*
+ * create a hard link between files in an AFS filesystem
+ */
+static int afs_link(struct dentry *from, struct inode *dir,
+ struct dentry *dentry)
+{
+ struct afs_vnode *dvnode, *vnode;
+ struct key *key;
+ int ret;
+
+ vnode = AFS_FS_I(d_inode(from));
+ dvnode = AFS_FS_I(dir);
+
+ _enter("{%x:%u},{%x:%u},{%pd}",
+ vnode->fid.vid, vnode->fid.vnode,
+ dvnode->fid.vid, dvnode->fid.vnode,
+ dentry);
+
+ key = afs_request_key(dvnode->volume->cell);
+ if (IS_ERR(key)) {
+ ret = PTR_ERR(key);
+ goto error;
+ }
+
+ ret = afs_vnode_link(dvnode, vnode, key, dentry->d_name.name);
+ if (ret < 0)
+ goto link_error;
+
+ ihold(&vnode->vfs_inode);
+ d_instantiate(dentry, &vnode->vfs_inode);
+ key_put(key);
+ _leave(" = 0");
+ return 0;
+
+link_error:
+ key_put(key);
+error:
+ d_drop(dentry);
+ _leave(" = %d", ret);
+ return ret;
+}
+
+/*
+ * create a symlink in an AFS filesystem
+ */
+static int afs_symlink(struct inode *dir, struct dentry *dentry,
+ const char *content)
+{
+ struct afs_file_status status;
+ struct afs_server *server;
+ struct afs_vnode *dvnode, *vnode;
+ struct afs_fid fid;
+ struct inode *inode;
+ struct key *key;
+ int ret;
+
+ dvnode = AFS_FS_I(dir);
+
+ _enter("{%x:%u},{%pd},%s",
+ dvnode->fid.vid, dvnode->fid.vnode, dentry,
+ content);
+
+ ret = -EINVAL;
+ if (strlen(content) >= AFSPATHMAX)
+ goto error;
+
+ key = afs_request_key(dvnode->volume->cell);
+ if (IS_ERR(key)) {
+ ret = PTR_ERR(key);
+ goto error;
+ }
+
+ ret = afs_vnode_symlink(dvnode, key, dentry->d_name.name, content,
+ &fid, &status, &server);
+ if (ret < 0)
+ goto create_error;
+
+ inode = afs_iget(dir->i_sb, key, &fid, &status, NULL);
+ if (IS_ERR(inode)) {
+ /* ENOMEM at a really inconvenient time - just abandon the new
+ * directory on the server */
+ ret = PTR_ERR(inode);
+ goto iget_error;
+ }
+
+ /* apply the status report we've got for the new vnode */
+ vnode = AFS_FS_I(inode);
+ spin_lock(&vnode->lock);
+ vnode->update_cnt++;
+ spin_unlock(&vnode->lock);
+ afs_vnode_finalise_status_update(vnode, server);
+ afs_put_server(server);
+
+ d_instantiate(dentry, inode);
+ if (d_unhashed(dentry)) {
+ _debug("not hashed");
+ d_rehash(dentry);
+ }
+ key_put(key);
+ _leave(" = 0");
+ return 0;
+
+iget_error:
+ afs_put_server(server);
+create_error:
+ key_put(key);
+error:
+ d_drop(dentry);
+ _leave(" = %d", ret);
+ return ret;
+}
+
+/*
+ * rename a file in an AFS filesystem and/or move it between directories
+ */
+static int afs_rename(struct inode *old_dir, struct dentry *old_dentry,
+ struct inode *new_dir, struct dentry *new_dentry)
+{
+ struct afs_vnode *orig_dvnode, *new_dvnode, *vnode;
+ struct key *key;
+ int ret;
+
+ vnode = AFS_FS_I(d_inode(old_dentry));
+ orig_dvnode = AFS_FS_I(old_dir);
+ new_dvnode = AFS_FS_I(new_dir);
+
+ _enter("{%x:%u},{%x:%u},{%x:%u},{%pd}",
+ orig_dvnode->fid.vid, orig_dvnode->fid.vnode,
+ vnode->fid.vid, vnode->fid.vnode,
+ new_dvnode->fid.vid, new_dvnode->fid.vnode,
+ new_dentry);
+
+ key = afs_request_key(orig_dvnode->volume->cell);
+ if (IS_ERR(key)) {
+ ret = PTR_ERR(key);
+ goto error;
+ }
+
+ ret = afs_vnode_rename(orig_dvnode, new_dvnode, key,
+ old_dentry->d_name.name,
+ new_dentry->d_name.name);
+ if (ret < 0)
+ goto rename_error;
+ key_put(key);
+ _leave(" = 0");
+ return 0;
+
+rename_error:
+ key_put(key);
+error:
+ d_drop(new_dentry);
+ _leave(" = %d", ret);
+ return ret;
+}