// 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 #include #include #include #include #include #include #include #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 inode *dir, struct dentry *dentry, umode_t mode, bool excl); static int afs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode); static int afs_rmdir(struct inode *dir, struct dentry *dentry); static int afs_unlink(struct inode *dir, struct dentry *dentry); static int afs_link(struct dentry *from, struct inode *dir, struct dentry *dentry); static int afs_symlink(struct inode *dir, struct dentry *dentry, const char *content); static int afs_rename(struct inode *old_dir, struct dentry *old_dentry, struct inode *new_dir, struct dentry *new_dentry, unsigned int flags); static int afs_dir_releasepage(struct page *page, gfp_t gfp_flags); static void afs_dir_invalidatepage(struct page *page, unsigned int offset, unsigned int length); static int afs_dir_set_page_dirty(struct page *page) { 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 = { .set_page_dirty = afs_dir_set_page_dirty, .releasepage = afs_dir_releasepage, .invalidatepage = afs_dir_invalidatepage, }; 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]; }; /* * check that a directory page is valid */ static bool afs_dir_check_page(struct afs_vnode *dvnode, struct page *page, loff_t i_size) { struct afs_xdr_dir_page *dbuf; loff_t latter, off; int tmp, qty; /* Determine how many magic numbers there should be in this page, but * we must take care because the directory may change size under us. */ off = page_offset(page); if (i_size <= off) goto checked; latter = i_size - off; if (latter >= PAGE_SIZE) qty = PAGE_SIZE; else qty = latter; qty /= sizeof(union afs_xdr_dir_block); /* check them */ dbuf = kmap(page); for (tmp = 0; tmp < qty; tmp++) { if (dbuf->blocks[tmp].hdr.magic != AFS_DIR_MAGIC) { printk("kAFS: %s(%lx): bad magic %d/%d is %04hx\n", __func__, dvnode->vfs_inode.i_ino, tmp, qty, ntohs(dbuf->blocks[tmp].hdr.magic)); trace_afs_dir_check_failed(dvnode, off, i_size); kunmap(page); 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 page * *should* be NUL-terminated anyway. */ ((u8 *)&dbuf->blocks[tmp])[AFS_DIR_BLOCK_SIZE - 1] = 0; } kunmap(page); checked: afs_stat_v(dvnode, n_read_dir); return true; error: return false; } /* * Check the contents of a directory that we've just read. */ static bool afs_dir_check_pages(struct afs_vnode *dvnode, struct afs_read *req) { struct afs_xdr_dir_page *dbuf; unsigned int i, j, qty = PAGE_SIZE / sizeof(union afs_xdr_dir_block); for (i = 0; i < req->nr_pages; i++) if (!afs_dir_check_page(dvnode, req->pages[i], req->actual_len)) goto bad; return true; bad: pr_warn("DIR %llx:%llx f=%llx l=%llx al=%llx r=%llx\n", dvnode->fid.vid, dvnode->fid.vnode, req->file_size, req->len, req->actual_len, req->remain); pr_warn("DIR %llx %x %x %x\n", req->pos, req->index, req->nr_pages, req->offset); for (i = 0; i < req->nr_pages; i++) { dbuf = kmap(req->pages[i]); for (j = 0; j < qty; j++) { union afs_xdr_dir_block *block = &dbuf->blocks[j]; pr_warn("[%02x] %32phN\n", i * qty + j, block); } kunmap(req->pages[i]); } return false; } /* * 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 pages 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 afs_read *req; loff_t i_size; int nr_pages, nr_inline, i, n; int ret = -ENOMEM; retry: i_size = i_size_read(&dvnode->vfs_inode); if (i_size < 2048) return ERR_PTR(afs_bad(dvnode, afs_file_error_dir_small)); if (i_size > 2048 * 1024) { trace_afs_file_error(dvnode, -EFBIG, afs_file_error_dir_big); return ERR_PTR(-EFBIG); } _enter("%llu", i_size); /* Get a request record to hold the page list. We want to hold it * inline if we can, but we don't want to make an order 1 allocation. */ nr_pages = (i_size + PAGE_SIZE - 1) / PAGE_SIZE; nr_inline = nr_pages; if (nr_inline > (PAGE_SIZE - sizeof(*req)) / sizeof(struct page *)) nr_inline = 0; req = kzalloc(struct_size(req, array, nr_inline), GFP_KERNEL); if (!req) return ERR_PTR(-ENOMEM); refcount_set(&req->usage, 1); req->nr_pages = nr_pages; 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 */ if (nr_inline > 0) { req->pages = req->array; } else { req->pages = kcalloc(nr_pages, sizeof(struct page *), GFP_KERNEL); if (!req->pages) goto error; } /* Get a list of all the pages that hold or will hold the directory * content. We need to fill in any gaps that we might find where the * memory reclaimer has been at work. If there are any gaps, we will * need to reread the entire directory contents. */ i = 0; do { n = find_get_pages_contig(dvnode->vfs_inode.i_mapping, i, req->nr_pages - i, req->pages + i); _debug("find %u at %u/%u", n, i, req->nr_pages); if (n == 0) { gfp_t gfp = dvnode->vfs_inode.i_mapping->gfp_mask; if (test_and_clear_bit(AFS_VNODE_DIR_VALID, &dvnode->flags)) afs_stat_v(dvnode, n_inval); ret = -ENOMEM; req->pages[i] = __page_cache_alloc(gfp); if (!req->pages[i]) goto error; ret = add_to_page_cache_lru(req->pages[i], dvnode->vfs_inode.i_mapping, i, gfp); if (ret < 0) goto error; attach_page_private(req->pages[i], (void *)1); unlock_page(req->pages[i]); i++; } else { i += n; } } while (i < req->nr_pages); /* 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, key, req); if (ret < 0) goto error_unlock; task_io_account_read(PAGE_SIZE * req->nr_pages); if (req->len < req->file_size) goto content_has_grown; /* Validate the data we just read. */ ret = -EIO; if (!afs_dir_check_pages(dvnode, req)) 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); content_has_grown: up_write(&dvnode->validate_lock); afs_put_read(req); goto retry; } /* * 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; size_t nlen; int tmp; _enter("%u,%x,%p,,",(unsigned)ctx->pos,blkoff,block); 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 ) { next = offset + 1; /* 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); 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)); _debug("ENT[%zu.%u]: %s %zu \"%s\"", blkoff / sizeof(union afs_xdr_dir_block), offset, (offset < curr ? "skip" : "fill"), nlen, dire->u.name); /* work out where the next possible entry is */ for (tmp = nlen; tmp > 15; tmp -= sizeof(union afs_xdr_dirent)) { if (next >= AFS_DIR_SLOTS_PER_BLOCK) { _debug("ENT[%zu.%u]:" " %u travelled beyond end dir block" " (len %u/%zu)", blkoff / sizeof(union afs_xdr_dir_block), offset, next, tmp, nlen); return afs_bad(dvnode, afs_file_error_dir_over_end); } if (!(block->hdr.bitmap[next / 8] & (1 << (next % 8)))) { _debug("ENT[%zu.%u]:" " %u unmarked extension (len %u/%zu)", blkoff / sizeof(union afs_xdr_dir_block), offset, next, tmp, nlen); return afs_bad(dvnode, afs_file_error_dir_unmarked_ext); } _debug("ENT[%zu.%u]: ext %u/%zu", blkoff / sizeof(union afs_xdr_dir_block), next, tmp, nlen); next++; } /* 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); struct afs_xdr_dir_page *dbuf; union afs_xdr_dir_block *dblock; struct afs_read *req; struct page *page; unsigned blkoff, limit; int ret; _enter("{%lu},%u,,", dir->i_ino, (unsigned)ctx->pos); if (test_bit(AFS_VNODE_DELETED, &AFS_FS_I(dir)->flags)) { _leave(" = -ESTALE"); return -ESTALE; } 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) { blkoff = ctx->pos & ~(sizeof(union afs_xdr_dir_block) - 1); /* Fetch the appropriate page from the directory and re-add it * to the LRU. */ page = req->pages[blkoff / PAGE_SIZE]; if (!page) { ret = afs_bad(dvnode, afs_file_error_dir_missing_page); break; } mark_page_accessed(page); limit = blkoff & ~(PAGE_SIZE - 1); dbuf = kmap(page); /* deal with the individual blocks stashed on this page */ do { dblock = &dbuf->blocks[(blkoff % PAGE_SIZE) / sizeof(union afs_xdr_dir_block)]; ret = afs_dir_iterate_block(dvnode, ctx, dblock, blkoff); if (ret != 1) { kunmap(page); goto out; } blkoff += sizeof(union afs_xdr_dir_block); } while (ctx->pos < dir->i_size && blkoff < limit); kunmap(page); 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; } ret = -ENOENT; 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->vfs_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->vfs_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->vfs_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 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->vfs_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->vfs_inode); if (vnode->vfs_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->vfs_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 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->vfs_inode); d_instantiate(op->dentry, &vp->vnode->vfs_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; } 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: 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 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 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); 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 */ ret = -ENOMEM; op->rename.tmp = d_alloc(new_dentry->d_parent, &new_dentry->d_name); if (!op->rename.tmp) goto error; ret = afs_sillyrename(new_dvnode, AFS_FS_I(d_inode(new_dentry)), new_dentry, op->key); if (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 page and clean up its private state if it's not busy * - return true if the page can now be released, false if not */ static int afs_dir_releasepage(struct page *page, gfp_t gfp_flags) { struct afs_vnode *dvnode = AFS_FS_I(page->mapping->host); _enter("{{%llx:%llu}[%lu]}", dvnode->fid.vid, dvnode->fid.vnode, page->index); detach_page_private(page); /* The directory will need reloading. */ if (test_and_clear_bit(AFS_VNODE_DIR_VALID, &dvnode->flags)) afs_stat_v(dvnode, n_relpg); return 1; } /* * invalidate part or all of a page * - release a page and clean up its private data if offset is 0 (indicating * the entire page) */ static void afs_dir_invalidatepage(struct page *page, unsigned int offset, unsigned int length) { struct afs_vnode *dvnode = AFS_FS_I(page->mapping->host); _enter("{%lu},%u,%u", page->index, offset, length); BUG_ON(!PageLocked(page)); /* 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 page is being invalidated */ if (offset == 0 && length == PAGE_SIZE) detach_page_private(page); }