diff options
Diffstat (limited to 'fs/afs/dir.c')
| -rw-r--r-- | fs/afs/dir.c | 2054 |
1 files changed, 2054 insertions, 0 deletions
diff --git a/fs/afs/dir.c b/fs/afs/dir.c new file mode 100644 index 0000000000..2df2e9ee13 --- /dev/null +++ b/fs/afs/dir.c @@ -0,0 +1,2054 @@ +// 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 bool afs_lookup_one_filldir(struct dir_context *ctx, const char *name, int nlen, + loff_t fpos, u64 ino, unsigned dtype); +static bool afs_lookup_filldir(struct dir_context *ctx, const char *name, int nlen, + loff_t fpos, u64 ino, unsigned dtype); +static int afs_create(struct mnt_idmap *idmap, struct inode *dir, + struct dentry *dentry, umode_t mode, bool excl); +static int afs_mkdir(struct mnt_idmap *idmap, 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 mnt_idmap *idmap, struct inode *dir, + struct dentry *dentry, const char *content); +static int afs_rename(struct mnt_idmap *idmap, 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, + .migrate_folio = filemap_migrate_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; + loff_t remote_size = 0; + + _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 < remote_size) + i_size = remote_size; + 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, ITER_DEST, &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 (IS_ERR(folio)) { + if (test_and_clear_bit(AFS_VNODE_DIR_VALID, &dvnode->flags)) + afs_stat_v(dvnode, n_inval); + folio = __filemap_get_folio(mapping, + i, FGP_LOCK | FGP_CREAT, + mapping->gfp_mask); + if (IS_ERR(folio)) { + ret = PTR_ERR(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); + remote_size = req->file_size; + 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; + } + + /* Don't expose silly rename entries to userspace. */ + if (nlen > 6 && + dire->u.name[0] == '.' && + ctx->actor != afs_lookup_filldir && + ctx->actor != afs_lookup_one_filldir && + memcmp(dire->u.name, ".__afs", 6) == 0) + 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 (IS_ERR(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 bool 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(" = true [keep looking]"); + return true; + } + + cookie->fid.vnode = ino; + cookie->fid.unique = dtype; + cookie->found = 1; + + _leave(" = false [found]"); + return false; +} + +/* + * 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 bool 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_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 false; + } + + return cookie->nr_fids < 50; +} + +/* + * 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 mnt_idmap *idmap, 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->mtime = current_time(dir); + 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 mnt_idmap *idmap, 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->mtime = current_time(dir); + 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 mnt_idmap *idmap, 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; + op->mtime = current_time(dir); + 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 mnt_idmap *idmap, 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); +} |