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	Version: linux-6.0.1 spark-3.0.0 hadoop-3.2.0-src hadoop-3.3.0-src spark-2.4.7 linux-4.15.13 hadoop-2.7.4-src Revert   Change

 // SPDX-License-Identifier: GPL-2.0-or-later
 /* dir.c: AFS filesystem directory handling
  *
  * Copyright (C) 2002, 2018 Red Hat, Inc. All Rights Reserved.
  * Written by David Howells (dhowells@redhat.com)
  */
 
 #include <linux/kernel.h>
 #include <linux/fs.h>
 #include <linux/namei.h>
 #include <linux/pagemap.h>
 #include <linux/swap.h>
 #include <linux/ctype.h>
 #include <linux/sched.h>
 #include <linux/task_io_accounting_ops.h>
 #include "internal.h"
 #include "afs_fs.h"
 #include "xdr_fs.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_iput(struct dentry *dentry, struct inode *inode);
 static int afs_lookup_one_filldir(struct dir_context *ctx, const char *name, int nlen,
                   loff_t fpos, u64 ino, unsigned dtype);
 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 user_namespace *mnt_userns, struct inode *dir,
               struct dentry *dentry, umode_t mode, bool excl);
 static int afs_mkdir(struct user_namespace *mnt_userns, 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 user_namespace *mnt_userns, struct inode *dir,
                struct dentry *dentry, const char *content);
 static int afs_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
               struct dentry *old_dentry, struct inode *new_dir,
               struct dentry *new_dentry, unsigned int flags);
 static bool afs_dir_release_folio(struct folio *folio, gfp_t gfp_flags);
 static void afs_dir_invalidate_folio(struct folio *folio, size_t offset,
                    size_t length);
 
 static bool afs_dir_dirty_folio(struct address_space *mapping,
         struct folio *folio)
 {
     BUG(); /* This should never happen. */
 }
 
 const struct file_operations afs_dir_file_operations = {
     .open       = afs_dir_open,
     .release    = afs_release,
     .iterate_shared = 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 address_space_operations afs_dir_aops = {
     .dirty_folio    = afs_dir_dirty_folio,
     .release_folio  = afs_dir_release_folio,
     .invalidate_folio = afs_dir_invalidate_folio,
 };
 
 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,
     .d_iput     = afs_d_iput,
 };
 
 struct afs_lookup_one_cookie {
     struct dir_context  ctx;
     struct qstr     name;
     bool            found;
     struct afs_fid      fid;
 };
 
 struct afs_lookup_cookie {
     struct dir_context  ctx;
     struct qstr     name;
     bool            found;
     bool            one_only;
     unsigned short      nr_fids;
     struct afs_fid      fids[50];
 };
 
 /*
  * Drop the refs that we're holding on the folios we were reading into.  We've
  * got refs on the first nr_pages pages.
  */
 static void afs_dir_read_cleanup(struct afs_read *req)
 {
     struct address_space *mapping = req->vnode->netfs.inode.i_mapping;
     struct folio *folio;
     pgoff_t last = req->nr_pages - 1;
 
     XA_STATE(xas, &mapping->i_pages, 0);
 
     if (unlikely(!req->nr_pages))
         return;
 
     rcu_read_lock();
     xas_for_each(&xas, folio, last) {
         if (xas_retry(&xas, folio))
             continue;
         BUG_ON(xa_is_value(folio));
         ASSERTCMP(folio_file_mapping(folio), ==, mapping);
 
         folio_put(folio);
     }
 
     rcu_read_unlock();
 }
 
 /*
  * check that a directory folio is valid
  */
 static bool afs_dir_check_folio(struct afs_vnode *dvnode, struct folio *folio,
                 loff_t i_size)
 {
     union afs_xdr_dir_block *block;
     size_t offset, size;
     loff_t pos;
 
     /* Determine how many magic numbers there should be in this folio, but
      * we must take care because the directory may change size under us.
      */
     pos = folio_pos(folio);
     if (i_size <= pos)
         goto checked;
 
     size = min_t(loff_t, folio_size(folio), i_size - pos);
     for (offset = 0; offset < size; offset += sizeof(*block)) {
         block = kmap_local_folio(folio, offset);
         if (block->hdr.magic != AFS_DIR_MAGIC) {
             printk("kAFS: %s(%lx): [%llx] bad magic %zx/%zx is %04hx\n",
                    __func__, dvnode->netfs.inode.i_ino,
                    pos, offset, size, ntohs(block->hdr.magic));
             trace_afs_dir_check_failed(dvnode, pos + offset, i_size);
             kunmap_local(block);
             trace_afs_file_error(dvnode, -EIO, afs_file_error_dir_bad_magic);
             goto error;
         }
 
         /* Make sure each block is NUL terminated so we can reasonably
          * use string functions on it.  The filenames in the folio
          * *should* be NUL-terminated anyway.
          */
         ((u8 *)block)[AFS_DIR_BLOCK_SIZE - 1] = 0;
 
         kunmap_local(block);
     }
 checked:
     afs_stat_v(dvnode, n_read_dir);
     return true;
 
 error:
     return false;
 }
 
 /*
  * Dump the contents of a directory.
  */
 static void afs_dir_dump(struct afs_vnode *dvnode, struct afs_read *req)
 {
     union afs_xdr_dir_block *block;
     struct address_space *mapping = dvnode->netfs.inode.i_mapping;
     struct folio *folio;
     pgoff_t last = req->nr_pages - 1;
     size_t offset, size;
 
     XA_STATE(xas, &mapping->i_pages, 0);
 
     pr_warn("DIR %llx:%llx f=%llx l=%llx al=%llx\n",
         dvnode->fid.vid, dvnode->fid.vnode,
         req->file_size, req->len, req->actual_len);
     pr_warn("DIR %llx %x %zx %zx\n",
         req->pos, req->nr_pages,
         req->iter->iov_offset,  iov_iter_count(req->iter));
 
     xas_for_each(&xas, folio, last) {
         if (xas_retry(&xas, folio))
             continue;
 
         BUG_ON(folio_file_mapping(folio) != mapping);
 
         size = min_t(loff_t, folio_size(folio), req->actual_len - folio_pos(folio));
         for (offset = 0; offset < size; offset += sizeof(*block)) {
             block = kmap_local_folio(folio, offset);
             pr_warn("[%02lx] %32phN\n", folio_index(folio) + offset, block);
             kunmap_local(block);
         }
     }
 }
 
 /*
  * Check all the blocks in a directory.  All the folios are held pinned.
  */
 static int afs_dir_check(struct afs_vnode *dvnode, struct afs_read *req)
 {
     struct address_space *mapping = dvnode->netfs.inode.i_mapping;
     struct folio *folio;
     pgoff_t last = req->nr_pages - 1;
     int ret = 0;
 
     XA_STATE(xas, &mapping->i_pages, 0);
 
     if (unlikely(!req->nr_pages))
         return 0;
 
     rcu_read_lock();
     xas_for_each(&xas, folio, last) {
         if (xas_retry(&xas, folio))
             continue;
 
         BUG_ON(folio_file_mapping(folio) != mapping);
 
         if (!afs_dir_check_folio(dvnode, folio, req->actual_len)) {
             afs_dir_dump(dvnode, req);
             ret = -EIO;
             break;
         }
     }
 
     rcu_read_unlock();
     return ret;
 }
 
 /*
  * 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_xdr_dir_block) != 2048);
     BUILD_BUG_ON(sizeof(union afs_xdr_dirent) != 32);
 
     if (test_bit(AFS_VNODE_DELETED, &AFS_FS_I(inode)->flags))
         return -ENOENT;
 
     return afs_open(inode, file);
 }
 
 /*
  * Read the directory into the pagecache in one go, scrubbing the previous
  * contents.  The list of folios is returned, pinning them so that they don't
  * get reclaimed during the iteration.
  */
 static struct afs_read *afs_read_dir(struct afs_vnode *dvnode, struct key *key)
     __acquires(&dvnode->validate_lock)
 {
     struct address_space *mapping = dvnode->netfs.inode.i_mapping;
     struct afs_read *req;
     loff_t i_size;
     int nr_pages, i;
     int ret;
 
     _enter("");
 
     req = kzalloc(sizeof(*req), GFP_KERNEL);
     if (!req)
         return ERR_PTR(-ENOMEM);
 
     refcount_set(&req->usage, 1);
     req->vnode = dvnode;
     req->key = key_get(key);
     req->cleanup = afs_dir_read_cleanup;
 
 expand:
     i_size = i_size_read(&dvnode->netfs.inode);
     if (i_size < 2048) {
         ret = afs_bad(dvnode, afs_file_error_dir_small);
         goto error;
     }
     if (i_size > 2048 * 1024) {
         trace_afs_file_error(dvnode, -EFBIG, afs_file_error_dir_big);
         ret = -EFBIG;
         goto error;
     }
 
     _enter("%llu", i_size);
 
     nr_pages = (i_size + PAGE_SIZE - 1) / PAGE_SIZE;
 
     req->actual_len = i_size; /* May change */
     req->len = nr_pages * PAGE_SIZE; /* We can ask for more than there is */
     req->data_version = dvnode->status.data_version; /* May change */
     iov_iter_xarray(&req->def_iter, READ, &dvnode->netfs.inode.i_mapping->i_pages,
             0, i_size);
     req->iter = &req->def_iter;
 
     /* Fill in any gaps that we might find where the memory reclaimer has
      * been at work and pin all the folios.  If there are any gaps, we will
      * need to reread the entire directory contents.
      */
     i = req->nr_pages;
     while (i < nr_pages) {
         struct folio *folio;
 
         folio = filemap_get_folio(mapping, i);
         if (!folio) {
             if (test_and_clear_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
                 afs_stat_v(dvnode, n_inval);
 
             ret = -ENOMEM;
             folio = __filemap_get_folio(mapping,
                             i, FGP_LOCK | FGP_CREAT,
                             mapping->gfp_mask);
             if (!folio)
                 goto error;
             folio_attach_private(folio, (void *)1);
             folio_unlock(folio);
         }
 
         req->nr_pages += folio_nr_pages(folio);
         i += folio_nr_pages(folio);
     }
 
     /* If we're going to reload, we need to lock all the pages to prevent
      * races.
      */
     ret = -ERESTARTSYS;
     if (down_read_killable(&dvnode->validate_lock) < 0)
         goto error;
 
     if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
         goto success;
 
     up_read(&dvnode->validate_lock);
     if (down_write_killable(&dvnode->validate_lock) < 0)
         goto error;
 
     if (!test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags)) {
         trace_afs_reload_dir(dvnode);
         ret = afs_fetch_data(dvnode, req);
         if (ret < 0)
             goto error_unlock;
 
         task_io_account_read(PAGE_SIZE * req->nr_pages);
 
         if (req->len < req->file_size) {
             /* The content has grown, so we need to expand the
              * buffer.
              */
             up_write(&dvnode->validate_lock);
             goto expand;
         }
 
         /* Validate the data we just read. */
         ret = afs_dir_check(dvnode, req);
         if (ret < 0)
             goto error_unlock;
 
         // TODO: Trim excess pages
 
         set_bit(AFS_VNODE_DIR_VALID, &dvnode->flags);
     }
 
     downgrade_write(&dvnode->validate_lock);
 success:
     return req;
 
 error_unlock:
     up_write(&dvnode->validate_lock);
 error:
     afs_put_read(req);
     _leave(" = %d", ret);
     return ERR_PTR(ret);
 }
 
 /*
  * deal with one block in an AFS directory
  */
 static int afs_dir_iterate_block(struct afs_vnode *dvnode,
                  struct dir_context *ctx,
                  union afs_xdr_dir_block *block,
                  unsigned blkoff)
 {
     union afs_xdr_dirent *dire;
     unsigned offset, next, curr, nr_slots;
     size_t nlen;
     int tmp;
 
     _enter("%llx,%x", ctx->pos, blkoff);
 
     curr = (ctx->pos - blkoff) / sizeof(union afs_xdr_dirent);
 
     /* walk through the block, an entry at a time */
     for (offset = (blkoff == 0 ? AFS_DIR_RESV_BLOCKS0 : AFS_DIR_RESV_BLOCKS);
          offset < AFS_DIR_SLOTS_PER_BLOCK;
          offset = next
          ) {
         /* skip entries marked unused in the bitmap */
         if (!(block->hdr.bitmap[offset / 8] &
               (1 << (offset % 8)))) {
             _debug("ENT[%zu.%u]: unused",
                    blkoff / sizeof(union afs_xdr_dir_block), offset);
             next = offset + 1;
             if (offset >= curr)
                 ctx->pos = blkoff +
                     next * sizeof(union afs_xdr_dirent);
             continue;
         }
 
         /* got a valid entry */
         dire = &block->dirents[offset];
         nlen = strnlen(dire->u.name,
                    sizeof(*block) -
                    offset * sizeof(union afs_xdr_dirent));
         if (nlen > AFSNAMEMAX - 1) {
             _debug("ENT[%zu]: name too long (len %u/%zu)",
                    blkoff / sizeof(union afs_xdr_dir_block),
                    offset, nlen);
             return afs_bad(dvnode, afs_file_error_dir_name_too_long);
         }
 
         _debug("ENT[%zu.%u]: %s %zu \"%s\"",
                blkoff / sizeof(union afs_xdr_dir_block), offset,
                (offset < curr ? "skip" : "fill"),
                nlen, dire->u.name);
 
         nr_slots = afs_dir_calc_slots(nlen);
         next = offset + nr_slots;
         if (next > AFS_DIR_SLOTS_PER_BLOCK) {
             _debug("ENT[%zu.%u]:"
                    " %u extends beyond end dir block"
                    " (len %zu)",
                    blkoff / sizeof(union afs_xdr_dir_block),
                    offset, next, nlen);
             return afs_bad(dvnode, afs_file_error_dir_over_end);
         }
 
         /* Check that the name-extension dirents are all allocated */
         for (tmp = 1; tmp < nr_slots; tmp++) {
             unsigned int ix = offset + tmp;
             if (!(block->hdr.bitmap[ix / 8] & (1 << (ix % 8)))) {
                 _debug("ENT[%zu.u]:"
                        " %u unmarked extension (%u/%u)",
                        blkoff / sizeof(union afs_xdr_dir_block),
                        offset, tmp, nr_slots);
                 return afs_bad(dvnode, afs_file_error_dir_unmarked_ext);
             }
         }
 
         /* skip if starts before the current position */
         if (offset < curr) {
             if (next > curr)
                 ctx->pos = blkoff + next * sizeof(union afs_xdr_dirent);
             continue;
         }
 
         /* found the next entry */
         if (!dir_emit(ctx, dire->u.name, nlen,
                   ntohl(dire->u.vnode),
                   (ctx->actor == afs_lookup_filldir ||
                    ctx->actor == afs_lookup_one_filldir)?
                   ntohl(dire->u.unique) : DT_UNKNOWN)) {
             _leave(" = 0 [full]");
             return 0;
         }
 
         ctx->pos = blkoff + next * sizeof(union afs_xdr_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, afs_dataversion_t *_dir_version)
 {
     struct afs_vnode *dvnode = AFS_FS_I(dir);
     union afs_xdr_dir_block *dblock;
     struct afs_read *req;
     struct folio *folio;
     unsigned offset, size;
     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;
     }
 
     req = afs_read_dir(dvnode, key);
     if (IS_ERR(req))
         return PTR_ERR(req);
     *_dir_version = req->data_version;
 
     /* round the file position up to the next entry boundary */
     ctx->pos += sizeof(union afs_xdr_dirent) - 1;
     ctx->pos &= ~(sizeof(union afs_xdr_dirent) - 1);
 
     /* walk through the blocks in sequence */
     ret = 0;
     while (ctx->pos < req->actual_len) {
         /* Fetch the appropriate folio from the directory and re-add it
          * to the LRU.  We have all the pages pinned with an extra ref.
          */
         folio = __filemap_get_folio(dir->i_mapping, ctx->pos / PAGE_SIZE,
                         FGP_ACCESSED, 0);
         if (!folio) {
             ret = afs_bad(dvnode, afs_file_error_dir_missing_page);
             break;
         }
 
         offset = round_down(ctx->pos, sizeof(*dblock)) - folio_file_pos(folio);
         size = min_t(loff_t, folio_size(folio),
                  req->actual_len - folio_file_pos(folio));
 
         do {
             dblock = kmap_local_folio(folio, offset);
             ret = afs_dir_iterate_block(dvnode, ctx, dblock,
                             folio_file_pos(folio) + offset);
             kunmap_local(dblock);
             if (ret != 1)
                 goto out;
 
         } while (offset += sizeof(*dblock), offset < size);
 
         ret = 0;
     }
 
 out:
     up_read(&dvnode->validate_lock);
     afs_put_read(req);
     _leave(" = %d", ret);
     return ret;
 }
 
 /*
  * read an AFS directory
  */
 static int afs_readdir(struct file *file, struct dir_context *ctx)
 {
     afs_dataversion_t dir_version;
 
     return afs_dir_iterate(file_inode(file), ctx, afs_file_key(file),
                    &dir_version);
 }
 
 /*
  * Search the directory for a single name
  * - if afs_dir_iterate_block() spots this function, it'll pass the FID
  *   uniquifier through dtype
  */
 static int afs_lookup_one_filldir(struct dir_context *ctx, const char *name,
                   int nlen, loff_t fpos, u64 ino, unsigned dtype)
 {
     struct afs_lookup_one_cookie *cookie =
         container_of(ctx, struct afs_lookup_one_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_xdr_dir_block) != 2048);
     BUILD_BUG_ON(sizeof(union afs_xdr_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 of a single name in a directory
  * - just returns the FID the dentry name maps to if found
  */
 static int afs_do_lookup_one(struct inode *dir, struct dentry *dentry,
                  struct afs_fid *fid, struct key *key,
                  afs_dataversion_t *_dir_version)
 {
     struct afs_super_info *as = dir->i_sb->s_fs_info;
     struct afs_lookup_one_cookie cookie = {
         .ctx.actor = afs_lookup_one_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, _dir_version);
     if (ret < 0) {
         _leave(" = %d [iter]", ret);
         return ret;
     }
 
     if (!cookie.found) {
         _leave(" = -ENOENT [not found]");
         return -ENOENT;
     }
 
     *fid = cookie.fid;
     _leave(" = 0 { vn=%llu u=%u }", fid->vnode, fid->unique);
     return 0;
 }
 
 /*
  * 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);
     int ret;
 
     _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_xdr_dir_block) != 2048);
     BUILD_BUG_ON(sizeof(union afs_xdr_dirent) != 32);
 
     if (cookie->found) {
         if (cookie->nr_fids < 50) {
             cookie->fids[cookie->nr_fids].vnode = ino;
             cookie->fids[cookie->nr_fids].unique    = dtype;
             cookie->nr_fids++;
         }
     } else if (cookie->name.len == nlen &&
            memcmp(cookie->name.name, name, nlen) == 0) {
         cookie->fids[1].vnode   = ino;
         cookie->fids[1].unique  = dtype;
         cookie->found = 1;
         if (cookie->one_only)
             return -1;
     }
 
     ret = cookie->nr_fids >= 50 ? -1 : 0;
     _leave(" = %d", ret);
     return ret;
 }
 
 /*
  * Deal with the result of a successful lookup operation.  Turn all the files
  * into inodes and save the first one - which is the one we actually want.
  */
 static void afs_do_lookup_success(struct afs_operation *op)
 {
     struct afs_vnode_param *vp;
     struct afs_vnode *vnode;
     struct inode *inode;
     u32 abort_code;
     int i;
 
     _enter("");
 
     for (i = 0; i < op->nr_files; i++) {
         switch (i) {
         case 0:
             vp = &op->file[0];
             abort_code = vp->scb.status.abort_code;
             if (abort_code != 0) {
                 op->ac.abort_code = abort_code;
                 op->error = afs_abort_to_error(abort_code);
             }
             break;
 
         case 1:
             vp = &op->file[1];
             break;
 
         default:
             vp = &op->more_files[i - 2];
             break;
         }
 
         if (!vp->scb.have_status && !vp->scb.have_error)
             continue;
 
         _debug("do [%u]", i);
         if (vp->vnode) {
             if (!test_bit(AFS_VNODE_UNSET, &vp->vnode->flags))
                 afs_vnode_commit_status(op, vp);
         } else if (vp->scb.status.abort_code == 0) {
             inode = afs_iget(op, vp);
             if (!IS_ERR(inode)) {
                 vnode = AFS_FS_I(inode);
                 afs_cache_permit(vnode, op->key,
                          0 /* Assume vnode->cb_break is 0 */ +
                          op->cb_v_break,
                          &vp->scb);
                 vp->vnode = vnode;
                 vp->put_vnode = true;
             }
         } else {
             _debug("- abort %d %llx:%llx.%x",
                    vp->scb.status.abort_code,
                    vp->fid.vid, vp->fid.vnode, vp->fid.unique);
         }
     }
 
     _leave("");
 }
 
 static const struct afs_operation_ops afs_inline_bulk_status_operation = {
     .issue_afs_rpc  = afs_fs_inline_bulk_status,
     .issue_yfs_rpc  = yfs_fs_inline_bulk_status,
     .success    = afs_do_lookup_success,
 };
 
 static const struct afs_operation_ops afs_lookup_fetch_status_operation = {
     .issue_afs_rpc  = afs_fs_fetch_status,
     .issue_yfs_rpc  = yfs_fs_fetch_status,
     .success    = afs_do_lookup_success,
     .aborted    = afs_check_for_remote_deletion,
 };
 
 /*
  * See if we know that the server we expect to use doesn't support
  * FS.InlineBulkStatus.
  */
 static bool afs_server_supports_ibulk(struct afs_vnode *dvnode)
 {
     struct afs_server_list *slist;
     struct afs_volume *volume = dvnode->volume;
     struct afs_server *server;
     bool ret = true;
     int i;
 
     if (!test_bit(AFS_VOLUME_MAYBE_NO_IBULK, &volume->flags))
         return true;
 
     rcu_read_lock();
     slist = rcu_dereference(volume->servers);
 
     for (i = 0; i < slist->nr_servers; i++) {
         server = slist->servers[i].server;
         if (server == dvnode->cb_server) {
             if (test_bit(AFS_SERVER_FL_NO_IBULK, &server->flags))
                 ret = false;
             break;
         }
     }
 
     rcu_read_unlock();
     return ret;
 }
 
 /*
  * Do a lookup in a directory.  We make use of bulk lookup to query a slew of
  * files in one go and create inodes for them.  The inode of the file we were
  * asked for is returned.
  */
 static struct inode *afs_do_lookup(struct inode *dir, struct dentry *dentry,
                    struct key *key)
 {
     struct afs_lookup_cookie *cookie;
     struct afs_vnode_param *vp;
     struct afs_operation *op;
     struct afs_vnode *dvnode = AFS_FS_I(dir), *vnode;
     struct inode *inode = NULL, *ti;
     afs_dataversion_t data_version = READ_ONCE(dvnode->status.data_version);
     long ret;
     int i;
 
     _enter("{%lu},%p{%pd},", dir->i_ino, dentry, dentry);
 
     cookie = kzalloc(sizeof(struct afs_lookup_cookie), GFP_KERNEL);
     if (!cookie)
         return ERR_PTR(-ENOMEM);
 
     for (i = 0; i < ARRAY_SIZE(cookie->fids); i++)
         cookie->fids[i].vid = dvnode->fid.vid;
     cookie->ctx.actor = afs_lookup_filldir;
     cookie->name = dentry->d_name;
     cookie->nr_fids = 2; /* slot 0 is saved for the fid we actually want
                   * and slot 1 for the directory */
 
     if (!afs_server_supports_ibulk(dvnode))
         cookie->one_only = true;
 
     /* search the directory */
     ret = afs_dir_iterate(dir, &cookie->ctx, key, &data_version);
     if (ret < 0)
         goto out;
 
     dentry->d_fsdata = (void *)(unsigned long)data_version;
 
     ret = -ENOENT;
     if (!cookie->found)
         goto out;
 
     /* Check to see if we already have an inode for the primary fid. */
     inode = ilookup5(dir->i_sb, cookie->fids[1].vnode,
              afs_ilookup5_test_by_fid, &cookie->fids[1]);
     if (inode)
         goto out; /* We do */
 
     /* Okay, we didn't find it.  We need to query the server - and whilst
      * we're doing that, we're going to attempt to look up a bunch of other
      * vnodes also.
      */
     op = afs_alloc_operation(NULL, dvnode->volume);
     if (IS_ERR(op)) {
         ret = PTR_ERR(op);
         goto out;
     }
 
     afs_op_set_vnode(op, 0, dvnode);
     afs_op_set_fid(op, 1, &cookie->fids[1]);
 
     op->nr_files = cookie->nr_fids;
     _debug("nr_files %u", op->nr_files);
 
     /* Need space for examining all the selected files */
     op->error = -ENOMEM;
     if (op->nr_files > 2) {
         op->more_files = kvcalloc(op->nr_files - 2,
                       sizeof(struct afs_vnode_param),
                       GFP_KERNEL);
         if (!op->more_files)
             goto out_op;
 
         for (i = 2; i < op->nr_files; i++) {
             vp = &op->more_files[i - 2];
             vp->fid = cookie->fids[i];
 
             /* Find any inodes that already exist and get their
              * callback counters.
              */
             ti = ilookup5_nowait(dir->i_sb, vp->fid.vnode,
                          afs_ilookup5_test_by_fid, &vp->fid);
             if (!IS_ERR_OR_NULL(ti)) {
                 vnode = AFS_FS_I(ti);
                 vp->dv_before = vnode->status.data_version;
                 vp->cb_break_before = afs_calc_vnode_cb_break(vnode);
                 vp->vnode = vnode;
                 vp->put_vnode = true;
                 vp->speculative = true; /* vnode not locked */
             }
         }
     }
 
     /* Try FS.InlineBulkStatus first.  Abort codes for the individual
      * lookups contained therein are stored in the reply without aborting
      * the whole operation.
      */
     op->error = -ENOTSUPP;
     if (!cookie->one_only) {
         op->ops = &afs_inline_bulk_status_operation;
         afs_begin_vnode_operation(op);
         afs_wait_for_operation(op);
     }
 
     if (op->error == -ENOTSUPP) {
         /* We could try FS.BulkStatus next, but this aborts the entire
          * op if any of the lookups fails - so, for the moment, revert
          * to FS.FetchStatus for op->file[1].
          */
         op->fetch_status.which = 1;
         op->ops = &afs_lookup_fetch_status_operation;
         afs_begin_vnode_operation(op);
         afs_wait_for_operation(op);
     }
     inode = ERR_PTR(op->error);
 
 out_op:
     if (op->error == 0) {
         inode = &op->file[1].vnode->netfs.inode;
         op->file[1].vnode = NULL;
     }
 
     if (op->file[0].scb.have_status)
         dentry->d_fsdata = (void *)(unsigned long)op->file[0].scb.status.data_version;
     else
         dentry->d_fsdata = (void *)(unsigned long)op->file[0].dv_before;
     ret = afs_put_operation(op);
 out:
     kfree(cookie);
     _leave("");
     return inode ?: ERR_PTR(ret);
 }
 
 /*
  * Look up an entry in a directory with @sys substitution.
  */
 static struct dentry *afs_lookup_atsys(struct inode *dir, struct dentry *dentry,
                        struct key *key)
 {
     struct afs_sysnames *subs;
     struct afs_net *net = afs_i2net(dir);
     struct dentry *ret;
     char *buf, *p, *name;
     int len, i;
 
     _enter("");
 
     ret = ERR_PTR(-ENOMEM);
     p = buf = kmalloc(AFSNAMEMAX, GFP_KERNEL);
     if (!buf)
         goto out_p;
     if (dentry->d_name.len > 4) {
         memcpy(p, dentry->d_name.name, dentry->d_name.len - 4);
         p += dentry->d_name.len - 4;
     }
 
     /* There is an ordered list of substitutes that we have to try. */
     read_lock(&net->sysnames_lock);
     subs = net->sysnames;
     refcount_inc(&subs->usage);
     read_unlock(&net->sysnames_lock);
 
     for (i = 0; i < subs->nr; i++) {
         name = subs->subs[i];
         len = dentry->d_name.len - 4 + strlen(name);
         if (len >= AFSNAMEMAX) {
             ret = ERR_PTR(-ENAMETOOLONG);
             goto out_s;
         }
 
         strcpy(p, name);
         ret = lookup_one_len(buf, dentry->d_parent, len);
         if (IS_ERR(ret) || d_is_positive(ret))
             goto out_s;
         dput(ret);
     }
 
     /* We don't want to d_add() the @sys dentry here as we don't want to
      * the cached dentry to hide changes to the sysnames list.
      */
     ret = NULL;
 out_s:
     afs_put_sysnames(subs);
     kfree(buf);
 out_p:
     key_put(key);
     return 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 *dvnode = AFS_FS_I(dir);
     struct afs_fid fid = {};
     struct inode *inode;
     struct dentry *d;
     struct key *key;
     int ret;
 
     _enter("{%llx:%llu},%p{%pd},",
            dvnode->fid.vid, dvnode->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, &dvnode->flags)) {
         _leave(" = -ESTALE");
         return ERR_PTR(-ESTALE);
     }
 
     key = afs_request_key(dvnode->volume->cell);
     if (IS_ERR(key)) {
         _leave(" = %ld [key]", PTR_ERR(key));
         return ERR_CAST(key);
     }
 
     ret = afs_validate(dvnode, key);
     if (ret < 0) {
         key_put(key);
         _leave(" = %d [val]", ret);
         return ERR_PTR(ret);
     }
 
     if (dentry->d_name.len >= 4 &&
         dentry->d_name.name[dentry->d_name.len - 4] == '@' &&
         dentry->d_name.name[dentry->d_name.len - 3] == 's' &&
         dentry->d_name.name[dentry->d_name.len - 2] == 'y' &&
         dentry->d_name.name[dentry->d_name.len - 1] == 's')
         return afs_lookup_atsys(dir, dentry, key);
 
     afs_stat_v(dvnode, n_lookup);
     inode = afs_do_lookup(dir, dentry, key);
     key_put(key);
     if (inode == ERR_PTR(-ENOENT))
         inode = afs_try_auto_mntpt(dentry, dir);
 
     if (!IS_ERR_OR_NULL(inode))
         fid = AFS_FS_I(inode)->fid;
 
     _debug("splice %p", dentry->d_inode);
     d = d_splice_alias(inode, dentry);
     if (!IS_ERR_OR_NULL(d)) {
         d->d_fsdata = dentry->d_fsdata;
         trace_afs_lookup(dvnode, &d->d_name, &fid);
     } else {
         trace_afs_lookup(dvnode, &dentry->d_name, &fid);
     }
     _leave("");
     return d;
 }
 
 /*
  * Check the validity of a dentry under RCU conditions.
  */
 static int afs_d_revalidate_rcu(struct dentry *dentry)
 {
     struct afs_vnode *dvnode;
     struct dentry *parent;
     struct inode *dir;
     long dir_version, de_version;
 
     _enter("%p", dentry);
 
     /* Check the parent directory is still valid first. */
     parent = READ_ONCE(dentry->d_parent);
     dir = d_inode_rcu(parent);
     if (!dir)
         return -ECHILD;
     dvnode = AFS_FS_I(dir);
     if (test_bit(AFS_VNODE_DELETED, &dvnode->flags))
         return -ECHILD;
 
     if (!afs_check_validity(dvnode))
         return -ECHILD;
 
     /* We only need to invalidate a dentry if the server's copy changed
      * behind our back.  If we made the change, it's no problem.  Note that
      * on a 32-bit system, we only have 32 bits in the dentry to store the
      * version.
      */
     dir_version = (long)READ_ONCE(dvnode->status.data_version);
     de_version = (long)READ_ONCE(dentry->d_fsdata);
     if (de_version != dir_version) {
         dir_version = (long)READ_ONCE(dvnode->invalid_before);
         if (de_version - dir_version < 0)
             return -ECHILD;
     }
 
     return 1; /* Still valid */
 }
 
 /*
  * 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 fid;
     struct dentry *parent;
     struct inode *inode;
     struct key *key;
     afs_dataversion_t dir_version, invalid_before;
     long de_version;
     int ret;
 
     if (flags & LOOKUP_RCU)
         return afs_d_revalidate_rcu(dentry);
 
     if (d_really_is_positive(dentry)) {
         vnode = AFS_FS_I(d_inode(dentry));
         _enter("{v={%llx:%llu} 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;
 
     /* Hold the parent dentry so we can peer at it */
     parent = dget_parent(dentry);
     dir = AFS_FS_I(d_inode(parent));
 
     /* validate the parent directory */
     afs_validate(dir, key);
 
     if (test_bit(AFS_VNODE_DELETED, &dir->flags)) {
         _debug("%pd: parent dir deleted", dentry);
         goto not_found;
     }
 
     /* We only need to invalidate a dentry if the server's copy changed
      * behind our back.  If we made the change, it's no problem.  Note that
      * on a 32-bit system, we only have 32 bits in the dentry to store the
      * version.
      */
     dir_version = dir->status.data_version;
     de_version = (long)dentry->d_fsdata;
     if (de_version == (long)dir_version)
         goto out_valid_noupdate;
 
     invalid_before = dir->invalid_before;
     if (de_version - (long)invalid_before >= 0)
         goto out_valid;
 
     _debug("dir modified");
     afs_stat_v(dir, n_reval);
 
     /* search the directory for this vnode */
     ret = afs_do_lookup_one(&dir->netfs.inode, dentry, &fid, key, &dir_version);
     switch (ret) {
     case 0:
         /* the filename maps to something */
         if (d_really_is_negative(dentry))
             goto not_found;
         inode = d_inode(dentry);
         if (is_bad_inode(inode)) {
             printk("kAFS: afs_d_revalidate: %pd2 has bad inode\n",
                    dentry);
             goto not_found;
         }
 
         vnode = AFS_FS_I(inode);
 
         /* if the vnode ID has changed, then the dirent points to a
          * different file */
         if (fid.vnode != vnode->fid.vnode) {
             _debug("%pd: dirent changed [%llu != %llu]",
                    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,
                    vnode->netfs.inode.i_generation);
             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 not_found;
     }
 
 out_valid:
     dentry->d_fsdata = (void *)(unsigned long)dir_version;
 out_valid_noupdate:
     dput(parent);
     key_put(key);
     _leave(" = 1 [valid]");
     return 1;
 
 not_found:
     _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;
 }
 
 /*
  * Clean up sillyrename files on dentry removal.
  */
 static void afs_d_iput(struct dentry *dentry, struct inode *inode)
 {
     if (dentry->d_flags & DCACHE_NFSFS_RENAMED)
         afs_silly_iput(dentry, inode);
     iput(inode);
 }
 
 /*
  * handle dentry release
  */
 void afs_d_release(struct dentry *dentry)
 {
     _enter("%pd", dentry);
 }
 
 void afs_check_for_remote_deletion(struct afs_operation *op)
 {
     struct afs_vnode *vnode = op->file[0].vnode;
 
     switch (op->ac.abort_code) {
     case VNOVNODE:
         set_bit(AFS_VNODE_DELETED, &vnode->flags);
         afs_break_callback(vnode, afs_cb_break_for_deleted);
     }
 }
 
 /*
  * Create a new inode for create/mkdir/symlink
  */
 static void afs_vnode_new_inode(struct afs_operation *op)
 {
     struct afs_vnode_param *vp = &op->file[1];
     struct afs_vnode *vnode;
     struct inode *inode;
 
     _enter("");
 
     ASSERTCMP(op->error, ==, 0);
 
     inode = afs_iget(op, vp);
     if (IS_ERR(inode)) {
         /* ENOMEM or EINTR at a really inconvenient time - just abandon
          * the new directory on the server.
          */
         op->error = PTR_ERR(inode);
         return;
     }
 
     vnode = AFS_FS_I(inode);
     set_bit(AFS_VNODE_NEW_CONTENT, &vnode->flags);
     if (!op->error)
         afs_cache_permit(vnode, op->key, vnode->cb_break, &vp->scb);
     d_instantiate(op->dentry, inode);
 }
 
 static void afs_create_success(struct afs_operation *op)
 {
     _enter("op=%08x", op->debug_id);
     op->ctime = op->file[0].scb.status.mtime_client;
     afs_vnode_commit_status(op, &op->file[0]);
     afs_update_dentry_version(op, &op->file[0], op->dentry);
     afs_vnode_new_inode(op);
 }
 
 static void afs_create_edit_dir(struct afs_operation *op)
 {
     struct afs_vnode_param *dvp = &op->file[0];
     struct afs_vnode_param *vp = &op->file[1];
     struct afs_vnode *dvnode = dvp->vnode;
 
     _enter("op=%08x", op->debug_id);
 
     down_write(&dvnode->validate_lock);
     if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags) &&
         dvnode->status.data_version == dvp->dv_before + dvp->dv_delta)
         afs_edit_dir_add(dvnode, &op->dentry->d_name, &vp->fid,
                  op->create.reason);
     up_write(&dvnode->validate_lock);
 }
 
 static void afs_create_put(struct afs_operation *op)
 {
     _enter("op=%08x", op->debug_id);
 
     if (op->error)
         d_drop(op->dentry);
 }
 
 static const struct afs_operation_ops afs_mkdir_operation = {
     .issue_afs_rpc  = afs_fs_make_dir,
     .issue_yfs_rpc  = yfs_fs_make_dir,
     .success    = afs_create_success,
     .aborted    = afs_check_for_remote_deletion,
     .edit_dir   = afs_create_edit_dir,
     .put        = afs_create_put,
 };
 
 /*
  * create a directory on an AFS filesystem
  */
 static int afs_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
              struct dentry *dentry, umode_t mode)
 {
     struct afs_operation *op;
     struct afs_vnode *dvnode = AFS_FS_I(dir);
 
     _enter("{%llx:%llu},{%pd},%ho",
            dvnode->fid.vid, dvnode->fid.vnode, dentry, mode);
 
     op = afs_alloc_operation(NULL, dvnode->volume);
     if (IS_ERR(op)) {
         d_drop(dentry);
         return PTR_ERR(op);
     }
 
     afs_op_set_vnode(op, 0, dvnode);
     op->file[0].dv_delta = 1;
     op->file[0].modification = true;
     op->file[0].update_ctime = true;
     op->dentry  = dentry;
     op->create.mode = S_IFDIR | mode;
     op->create.reason = afs_edit_dir_for_mkdir;
     op->ops     = &afs_mkdir_operation;
     return afs_do_sync_operation(op);
 }
 
 /*
  * Remove a subdir from a directory.
  */
 static void afs_dir_remove_subdir(struct dentry *dentry)
 {
     if (d_really_is_positive(dentry)) {
         struct afs_vnode *vnode = AFS_FS_I(d_inode(dentry));
 
         clear_nlink(&vnode->netfs.inode);
         set_bit(AFS_VNODE_DELETED, &vnode->flags);
         clear_bit(AFS_VNODE_CB_PROMISED, &vnode->flags);
         clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags);
     }
 }
 
 static void afs_rmdir_success(struct afs_operation *op)
 {
     _enter("op=%08x", op->debug_id);
     op->ctime = op->file[0].scb.status.mtime_client;
     afs_vnode_commit_status(op, &op->file[0]);
     afs_update_dentry_version(op, &op->file[0], op->dentry);
 }
 
 static void afs_rmdir_edit_dir(struct afs_operation *op)
 {
     struct afs_vnode_param *dvp = &op->file[0];
     struct afs_vnode *dvnode = dvp->vnode;
 
     _enter("op=%08x", op->debug_id);
     afs_dir_remove_subdir(op->dentry);
 
     down_write(&dvnode->validate_lock);
     if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags) &&
         dvnode->status.data_version == dvp->dv_before + dvp->dv_delta)
         afs_edit_dir_remove(dvnode, &op->dentry->d_name,
                     afs_edit_dir_for_rmdir);
     up_write(&dvnode->validate_lock);
 }
 
 static void afs_rmdir_put(struct afs_operation *op)
 {
     _enter("op=%08x", op->debug_id);
     if (op->file[1].vnode)
         up_write(&op->file[1].vnode->rmdir_lock);
 }
 
 static const struct afs_operation_ops afs_rmdir_operation = {
     .issue_afs_rpc  = afs_fs_remove_dir,
     .issue_yfs_rpc  = yfs_fs_remove_dir,
     .success    = afs_rmdir_success,
     .aborted    = afs_check_for_remote_deletion,
     .edit_dir   = afs_rmdir_edit_dir,
     .put        = afs_rmdir_put,
 };
 
 /*
  * remove a directory from an AFS filesystem
  */
 static int afs_rmdir(struct inode *dir, struct dentry *dentry)
 {
     struct afs_operation *op;
     struct afs_vnode *dvnode = AFS_FS_I(dir), *vnode = NULL;
     int ret;
 
     _enter("{%llx:%llu},{%pd}",
            dvnode->fid.vid, dvnode->fid.vnode, dentry);
 
     op = afs_alloc_operation(NULL, dvnode->volume);
     if (IS_ERR(op))
         return PTR_ERR(op);
 
     afs_op_set_vnode(op, 0, dvnode);
     op->file[0].dv_delta = 1;
     op->file[0].modification = true;
     op->file[0].update_ctime = true;
 
     op->dentry  = dentry;
     op->ops     = &afs_rmdir_operation;
 
     /* Try to make sure we have a callback promise on the victim. */
     if (d_really_is_positive(dentry)) {
         vnode = AFS_FS_I(d_inode(dentry));
         ret = afs_validate(vnode, op->key);
         if (ret < 0)
             goto error;
     }
 
     if (vnode) {
         ret = down_write_killable(&vnode->rmdir_lock);
         if (ret < 0)
             goto error;
         op->file[1].vnode = vnode;
     }
 
     return afs_do_sync_operation(op);
 
 error:
     return afs_put_operation(op);
 }
 
 /*
  * Remove a link to a file or symlink from a directory.
  *
  * If the file was not 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...
  */
 static void afs_dir_remove_link(struct afs_operation *op)
 {
     struct afs_vnode *dvnode = op->file[0].vnode;
     struct afs_vnode *vnode = op->file[1].vnode;
     struct dentry *dentry = op->dentry;
     int ret;
 
     if (op->error != 0 ||
         (op->file[1].scb.have_status && op->file[1].scb.have_error))
         return;
     if (d_really_is_positive(dentry))
         return;
 
     if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) {
         /* Already done */
     } else if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags)) {
         write_seqlock(&vnode->cb_lock);
         drop_nlink(&vnode->netfs.inode);
         if (vnode->netfs.inode.i_nlink == 0) {
             set_bit(AFS_VNODE_DELETED, &vnode->flags);
             __afs_break_callback(vnode, afs_cb_break_for_unlink);
         }
         write_sequnlock(&vnode->cb_lock);
     } else {
         afs_break_callback(vnode, afs_cb_break_for_unlink);
 
         if (test_bit(AFS_VNODE_DELETED, &vnode->flags))
             _debug("AFS_VNODE_DELETED");
 
         ret = afs_validate(vnode, op->key);
         if (ret != -ESTALE)
             op->error = ret;
     }
 
     _debug("nlink %d [val %d]", vnode->netfs.inode.i_nlink, op->error);
 }
 
 static void afs_unlink_success(struct afs_operation *op)
 {
     _enter("op=%08x", op->debug_id);
     op->ctime = op->file[0].scb.status.mtime_client;
     afs_check_dir_conflict(op, &op->file[0]);
     afs_vnode_commit_status(op, &op->file[0]);
     afs_vnode_commit_status(op, &op->file[1]);
     afs_update_dentry_version(op, &op->file[0], op->dentry);
     afs_dir_remove_link(op);
 }
 
 static void afs_unlink_edit_dir(struct afs_operation *op)
 {
     struct afs_vnode_param *dvp = &op->file[0];
     struct afs_vnode *dvnode = dvp->vnode;
 
     _enter("op=%08x", op->debug_id);
     down_write(&dvnode->validate_lock);
     if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags) &&
         dvnode->status.data_version == dvp->dv_before + dvp->dv_delta)
         afs_edit_dir_remove(dvnode, &op->dentry->d_name,
                     afs_edit_dir_for_unlink);
     up_write(&dvnode->validate_lock);
 }
 
 static void afs_unlink_put(struct afs_operation *op)
 {
     _enter("op=%08x", op->debug_id);
     if (op->unlink.need_rehash && op->error < 0 && op->error != -ENOENT)
         d_rehash(op->dentry);
 }
 
 static const struct afs_operation_ops afs_unlink_operation = {
     .issue_afs_rpc  = afs_fs_remove_file,
     .issue_yfs_rpc  = yfs_fs_remove_file,
     .success    = afs_unlink_success,
     .aborted    = afs_check_for_remote_deletion,
     .edit_dir   = afs_unlink_edit_dir,
     .put        = afs_unlink_put,
 };
 
 /*
  * Remove a file or symlink from an AFS filesystem.
  */
 static int afs_unlink(struct inode *dir, struct dentry *dentry)
 {
     struct afs_operation *op;
     struct afs_vnode *dvnode = AFS_FS_I(dir);
     struct afs_vnode *vnode = AFS_FS_I(d_inode(dentry));
     int ret;
 
     _enter("{%llx:%llu},{%pd}",
            dvnode->fid.vid, dvnode->fid.vnode, dentry);
 
     if (dentry->d_name.len >= AFSNAMEMAX)
         return -ENAMETOOLONG;
 
     op = afs_alloc_operation(NULL, dvnode->volume);
     if (IS_ERR(op))
         return PTR_ERR(op);
 
     afs_op_set_vnode(op, 0, dvnode);
     op->file[0].dv_delta = 1;
     op->file[0].modification = true;
     op->file[0].update_ctime = true;
 
     /* Try to make sure we have a callback promise on the victim. */
     ret = afs_validate(vnode, op->key);
     if (ret < 0) {
         op->error = ret;
         goto error;
     }
 
     spin_lock(&dentry->d_lock);
     if (d_count(dentry) > 1) {
         spin_unlock(&dentry->d_lock);
         /* Start asynchronous writeout of the inode */
         write_inode_now(d_inode(dentry), 0);
         op->error = afs_sillyrename(dvnode, vnode, dentry, op->key);
         goto error;
     }
     if (!d_unhashed(dentry)) {
         /* Prevent a race with RCU lookup. */
         __d_drop(dentry);
         op->unlink.need_rehash = true;
     }
     spin_unlock(&dentry->d_lock);
 
     op->file[1].vnode = vnode;
     op->file[1].update_ctime = true;
     op->file[1].op_unlinked = true;
     op->dentry  = dentry;
     op->ops     = &afs_unlink_operation;
     afs_begin_vnode_operation(op);
     afs_wait_for_operation(op);
 
     /* If there was a conflict with a third party, check the status of the
      * unlinked vnode.
      */
     if (op->error == 0 && (op->flags & AFS_OPERATION_DIR_CONFLICT)) {
         op->file[1].update_ctime = false;
         op->fetch_status.which = 1;
         op->ops = &afs_fetch_status_operation;
         afs_begin_vnode_operation(op);
         afs_wait_for_operation(op);
     }
 
     return afs_put_operation(op);
 
 error:
     return afs_put_operation(op);
 }
 
 static const struct afs_operation_ops afs_create_operation = {
     .issue_afs_rpc  = afs_fs_create_file,
     .issue_yfs_rpc  = yfs_fs_create_file,
     .success    = afs_create_success,
     .aborted    = afs_check_for_remote_deletion,
     .edit_dir   = afs_create_edit_dir,
     .put        = afs_create_put,
 };
 
 /*
  * create a regular file on an AFS filesystem
  */
 static int afs_create(struct user_namespace *mnt_userns, struct inode *dir,
               struct dentry *dentry, umode_t mode, bool excl)
 {
     struct afs_operation *op;
     struct afs_vnode *dvnode = AFS_FS_I(dir);
     int ret = -ENAMETOOLONG;
 
     _enter("{%llx:%llu},{%pd},%ho",
            dvnode->fid.vid, dvnode->fid.vnode, dentry, mode);
 
     if (dentry->d_name.len >= AFSNAMEMAX)
         goto error;
 
     op = afs_alloc_operation(NULL, dvnode->volume);
     if (IS_ERR(op)) {
         ret = PTR_ERR(op);
         goto error;
     }
 
     afs_op_set_vnode(op, 0, dvnode);
     op->file[0].dv_delta = 1;
     op->file[0].modification = true;
     op->file[0].update_ctime = true;
 
     op->dentry  = dentry;
     op->create.mode = S_IFREG | mode;
     op->create.reason = afs_edit_dir_for_create;
     op->ops     = &afs_create_operation;
     return afs_do_sync_operation(op);
 
 error:
     d_drop(dentry);
     _leave(" = %d", ret);
     return ret;
 }
 
 static void afs_link_success(struct afs_operation *op)
 {
     struct afs_vnode_param *dvp = &op->file[0];
     struct afs_vnode_param *vp = &op->file[1];
 
     _enter("op=%08x", op->debug_id);
     op->ctime = dvp->scb.status.mtime_client;
     afs_vnode_commit_status(op, dvp);
     afs_vnode_commit_status(op, vp);
     afs_update_dentry_version(op, dvp, op->dentry);
     if (op->dentry_2->d_parent == op->dentry->d_parent)
         afs_update_dentry_version(op, dvp, op->dentry_2);
     ihold(&vp->vnode->netfs.inode);
     d_instantiate(op->dentry, &vp->vnode->netfs.inode);
 }
 
 static void afs_link_put(struct afs_operation *op)
 {
     _enter("op=%08x", op->debug_id);
     if (op->error)
         d_drop(op->dentry);
 }
 
 static const struct afs_operation_ops afs_link_operation = {
     .issue_afs_rpc  = afs_fs_link,
     .issue_yfs_rpc  = yfs_fs_link,
     .success    = afs_link_success,
     .aborted    = afs_check_for_remote_deletion,
     .edit_dir   = afs_create_edit_dir,
     .put        = afs_link_put,
 };
 
 /*
  * 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_operation *op;
     struct afs_vnode *dvnode = AFS_FS_I(dir);
     struct afs_vnode *vnode = AFS_FS_I(d_inode(from));
     int ret = -ENAMETOOLONG;
 
     _enter("{%llx:%llu},{%llx:%llu},{%pd}",
            vnode->fid.vid, vnode->fid.vnode,
            dvnode->fid.vid, dvnode->fid.vnode,
            dentry);
 
     if (dentry->d_name.len >= AFSNAMEMAX)
         goto error;
 
     op = afs_alloc_operation(NULL, dvnode->volume);
     if (IS_ERR(op)) {
         ret = PTR_ERR(op);
         goto error;
     }
 
     ret = afs_validate(vnode, op->key);
     if (ret < 0)
         goto error_op;
 
     afs_op_set_vnode(op, 0, dvnode);
     afs_op_set_vnode(op, 1, vnode);
     op->file[0].dv_delta = 1;
     op->file[0].modification = true;
     op->file[0].update_ctime = true;
     op->file[1].update_ctime = true;
 
     op->dentry      = dentry;
     op->dentry_2        = from;
     op->ops         = &afs_link_operation;
     op->create.reason   = afs_edit_dir_for_link;
     return afs_do_sync_operation(op);
 
 error_op:
     afs_put_operation(op);
 error:
     d_drop(dentry);
     _leave(" = %d", ret);
     return ret;
 }
 
 static const struct afs_operation_ops afs_symlink_operation = {
     .issue_afs_rpc  = afs_fs_symlink,
     .issue_yfs_rpc  = yfs_fs_symlink,
     .success    = afs_create_success,
     .aborted    = afs_check_for_remote_deletion,
     .edit_dir   = afs_create_edit_dir,
     .put        = afs_create_put,
 };
 
 /*
  * create a symlink in an AFS filesystem
  */
 static int afs_symlink(struct user_namespace *mnt_userns, struct inode *dir,
                struct dentry *dentry, const char *content)
 {
     struct afs_operation *op;
     struct afs_vnode *dvnode = AFS_FS_I(dir);
     int ret;
 
     _enter("{%llx:%llu},{%pd},%s",
            dvnode->fid.vid, dvnode->fid.vnode, dentry,
            content);
 
     ret = -ENAMETOOLONG;
     if (dentry->d_name.len >= AFSNAMEMAX)
         goto error;
 
     ret = -EINVAL;
     if (strlen(content) >= AFSPATHMAX)
         goto error;
 
     op = afs_alloc_operation(NULL, dvnode->volume);
     if (IS_ERR(op)) {
         ret = PTR_ERR(op);
         goto error;
     }
 
     afs_op_set_vnode(op, 0, dvnode);
     op->file[0].dv_delta = 1;
 
     op->dentry      = dentry;
     op->ops         = &afs_symlink_operation;
     op->create.reason   = afs_edit_dir_for_symlink;
     op->create.symlink  = content;
     return afs_do_sync_operation(op);
 
 error:
     d_drop(dentry);
     _leave(" = %d", ret);
     return ret;
 }
 
 static void afs_rename_success(struct afs_operation *op)
 {
     _enter("op=%08x", op->debug_id);
 
     op->ctime = op->file[0].scb.status.mtime_client;
     afs_check_dir_conflict(op, &op->file[1]);
     afs_vnode_commit_status(op, &op->file[0]);
     if (op->file[1].vnode != op->file[0].vnode) {
         op->ctime = op->file[1].scb.status.mtime_client;
         afs_vnode_commit_status(op, &op->file[1]);
     }
 }
 
 static void afs_rename_edit_dir(struct afs_operation *op)
 {
     struct afs_vnode_param *orig_dvp = &op->file[0];
     struct afs_vnode_param *new_dvp = &op->file[1];
     struct afs_vnode *orig_dvnode = orig_dvp->vnode;
     struct afs_vnode *new_dvnode = new_dvp->vnode;
     struct afs_vnode *vnode = AFS_FS_I(d_inode(op->dentry));
     struct dentry *old_dentry = op->dentry;
     struct dentry *new_dentry = op->dentry_2;
     struct inode *new_inode;
 
     _enter("op=%08x", op->debug_id);
 
     if (op->rename.rehash) {
         d_rehash(op->rename.rehash);
         op->rename.rehash = NULL;
     }
 
     down_write(&orig_dvnode->validate_lock);
     if (test_bit(AFS_VNODE_DIR_VALID, &orig_dvnode->flags) &&
         orig_dvnode->status.data_version == orig_dvp->dv_before + orig_dvp->dv_delta)
         afs_edit_dir_remove(orig_dvnode, &old_dentry->d_name,
                     afs_edit_dir_for_rename_0);
 
     if (new_dvnode != orig_dvnode) {
         up_write(&orig_dvnode->validate_lock);
         down_write(&new_dvnode->validate_lock);
     }
 
     if (test_bit(AFS_VNODE_DIR_VALID, &new_dvnode->flags) &&
         new_dvnode->status.data_version == new_dvp->dv_before + new_dvp->dv_delta) {
         if (!op->rename.new_negative)
             afs_edit_dir_remove(new_dvnode, &new_dentry->d_name,
                         afs_edit_dir_for_rename_1);
 
         afs_edit_dir_add(new_dvnode, &new_dentry->d_name,
                  &vnode->fid, afs_edit_dir_for_rename_2);
     }
 
     new_inode = d_inode(new_dentry);
     if (new_inode) {
         spin_lock(&new_inode->i_lock);
         if (S_ISDIR(new_inode->i_mode))
             clear_nlink(new_inode);
         else if (new_inode->i_nlink > 0)
             drop_nlink(new_inode);
         spin_unlock(&new_inode->i_lock);
     }
 
     /* Now we can update d_fsdata on the dentries to reflect their
      * new parent's data_version.
      *
      * Note that if we ever implement RENAME_EXCHANGE, we'll have
      * to update both dentries with opposing dir versions.
      */
     afs_update_dentry_version(op, new_dvp, op->dentry);
     afs_update_dentry_version(op, new_dvp, op->dentry_2);
 
     d_move(old_dentry, new_dentry);
 
     up_write(&new_dvnode->validate_lock);
 }
 
 static void afs_rename_put(struct afs_operation *op)
 {
     _enter("op=%08x", op->debug_id);
     if (op->rename.rehash)
         d_rehash(op->rename.rehash);
     dput(op->rename.tmp);
     if (op->error)
         d_rehash(op->dentry);
 }
 
 static const struct afs_operation_ops afs_rename_operation = {
     .issue_afs_rpc  = afs_fs_rename,
     .issue_yfs_rpc  = yfs_fs_rename,
     .success    = afs_rename_success,
     .edit_dir   = afs_rename_edit_dir,
     .put        = afs_rename_put,
 };
 
 /*
  * rename a file in an AFS filesystem and/or move it between directories
  */
 static int afs_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
               struct dentry *old_dentry, struct inode *new_dir,
               struct dentry *new_dentry, unsigned int flags)
 {
     struct afs_operation *op;
     struct afs_vnode *orig_dvnode, *new_dvnode, *vnode;
     int ret;
 
     if (flags)
         return -EINVAL;
 
     /* Don't allow silly-rename files be moved around. */
     if (old_dentry->d_flags & DCACHE_NFSFS_RENAMED)
         return -EINVAL;
 
     vnode = AFS_FS_I(d_inode(old_dentry));
     orig_dvnode = AFS_FS_I(old_dir);
     new_dvnode = AFS_FS_I(new_dir);
 
     _enter("{%llx:%llu},{%llx:%llu},{%llx:%llu},{%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);
 
     op = afs_alloc_operation(NULL, orig_dvnode->volume);
     if (IS_ERR(op))
         return PTR_ERR(op);
 
     ret = afs_validate(vnode, op->key);
     op->error = ret;
     if (ret < 0)
         goto error;
 
     afs_op_set_vnode(op, 0, orig_dvnode);
     afs_op_set_vnode(op, 1, new_dvnode); /* May be same as orig_dvnode */
     op->file[0].dv_delta = 1;
     op->file[1].dv_delta = 1;
     op->file[0].modification = true;
     op->file[1].modification = true;
     op->file[0].update_ctime = true;
     op->file[1].update_ctime = true;
 
     op->dentry      = old_dentry;
     op->dentry_2        = new_dentry;
     op->rename.new_negative = d_is_negative(new_dentry);
     op->ops         = &afs_rename_operation;
 
     /* For non-directories, check whether the target is busy and if so,
      * make a copy of the dentry and then do a silly-rename.  If the
      * silly-rename succeeds, the copied dentry is hashed and becomes the
      * new target.
      */
     if (d_is_positive(new_dentry) && !d_is_dir(new_dentry)) {
         /* To prevent any new references to the target during the
          * rename, we unhash the dentry in advance.
          */
         if (!d_unhashed(new_dentry)) {
             d_drop(new_dentry);
             op->rename.rehash = new_dentry;
         }
 
         if (d_count(new_dentry) > 2) {
             /* copy the target dentry's name */
             op->rename.tmp = d_alloc(new_dentry->d_parent,
                          &new_dentry->d_name);
             if (!op->rename.tmp) {
                 op->error = -ENOMEM;
                 goto error;
             }
 
             ret = afs_sillyrename(new_dvnode,
                           AFS_FS_I(d_inode(new_dentry)),
                           new_dentry, op->key);
             if (ret) {
                 op->error = ret;
                 goto error;
             }
 
             op->dentry_2 = op->rename.tmp;
             op->rename.rehash = NULL;
             op->rename.new_negative = true;
         }
     }
 
     /* This bit is potentially nasty as there's a potential race with
      * afs_d_revalidate{,_rcu}().  We have to change d_fsdata on the dentry
      * to reflect it's new parent's new data_version after the op, but
      * d_revalidate may see old_dentry between the op having taken place
      * and the version being updated.
      *
      * So drop the old_dentry for now to make other threads go through
      * lookup instead - which we hold a lock against.
      */
     d_drop(old_dentry);
 
     return afs_do_sync_operation(op);
 
 error:
     return afs_put_operation(op);
 }
 
 /*
  * Release a directory folio and clean up its private state if it's not busy
  * - return true if the folio can now be released, false if not
  */
 static bool afs_dir_release_folio(struct folio *folio, gfp_t gfp_flags)
 {
     struct afs_vnode *dvnode = AFS_FS_I(folio_inode(folio));
 
     _enter("{{%llx:%llu}[%lu]}", dvnode->fid.vid, dvnode->fid.vnode, folio_index(folio));
 
     folio_detach_private(folio);
 
     /* The directory will need reloading. */
     if (test_and_clear_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
         afs_stat_v(dvnode, n_relpg);
     return true;
 }
 
 /*
  * Invalidate part or all of a folio.
  */
 static void afs_dir_invalidate_folio(struct folio *folio, size_t offset,
                    size_t length)
 {
     struct afs_vnode *dvnode = AFS_FS_I(folio_inode(folio));
 
     _enter("{%lu},%zu,%zu", folio->index, offset, length);
 
     BUG_ON(!folio_test_locked(folio));
 
     /* The directory will need reloading. */
     if (test_and_clear_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
         afs_stat_v(dvnode, n_inval);
 
     /* we clean up only if the entire folio is being invalidated */
     if (offset == 0 && length == folio_size(folio))
         folio_detach_private(folio);
 }

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