// 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, .listxattr = afs_listxattr, }; 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 inode **inodes; struct afs_status_cb *statuses; 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; set_page_private(req->pages[i], 1); SetPagePrivate(req->pages[i]); 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) 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[0].vnode = ino; cookie->fids[0].unique = dtype; cookie->found = 1; if (cookie->one_only) return -1; } ret = cookie->nr_fids >= 50 ? -1 : 0; _leave(" = %d", ret); 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_cb_interest *dcbi, *cbi = NULL; struct afs_super_info *as = dir->i_sb->s_fs_info; struct afs_status_cb *scb; struct afs_iget_data iget_data; struct afs_operation fc; struct afs_server *server; 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); int ret, 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); 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 */ read_seqlock_excl(&dvnode->cb_lock); dcbi = rcu_dereference_protected(dvnode->cb_interest, lockdep_is_held(&dvnode->cb_lock.lock)); if (dcbi) { server = dcbi->server; if (server && test_bit(AFS_SERVER_FL_NO_IBULK, &server->flags)) cookie->one_only = true; } read_sequnlock_excl(&dvnode->cb_lock); for (i = 0; i < 50; i++) cookie->fids[i].vid = as->volume->vid; /* search the directory */ ret = afs_dir_iterate(dir, &cookie->ctx, key, &data_version); if (ret < 0) { inode = ERR_PTR(ret); goto out; } dentry->d_fsdata = (void *)(unsigned long)data_version; inode = ERR_PTR(-ENOENT); if (!cookie->found) goto out; /* Check to see if we already have an inode for the primary fid. */ iget_data.fid = cookie->fids[0]; iget_data.volume = dvnode->volume; iget_data.cb_v_break = dvnode->volume->cb_v_break; iget_data.cb_s_break = 0; inode = ilookup5(dir->i_sb, cookie->fids[0].vnode, afs_iget5_test, &iget_data); if (inode) goto out; /* Need space for examining all the selected files */ inode = ERR_PTR(-ENOMEM); cookie->statuses = kvcalloc(cookie->nr_fids, sizeof(struct afs_status_cb), GFP_KERNEL); if (!cookie->statuses) goto out; cookie->inodes = kcalloc(cookie->nr_fids, sizeof(struct inode *), GFP_KERNEL); if (!cookie->inodes) goto out_s; cookie->fids[1] = dvnode->fid; cookie->statuses[1].cb_break = afs_calc_vnode_cb_break(dvnode); cookie->inodes[1] = igrab(&dvnode->vfs_inode); for (i = 2; i < cookie->nr_fids; i++) { scb = &cookie->statuses[i]; /* Find any inodes that already exist and get their * callback counters. */ iget_data.fid = cookie->fids[i]; ti = ilookup5_nowait(dir->i_sb, iget_data.fid.vnode, afs_iget5_test, &iget_data); if (!IS_ERR_OR_NULL(ti)) { vnode = AFS_FS_I(ti); scb->cb_break = afs_calc_vnode_cb_break(vnode); cookie->inodes[i] = ti; } } /* Try FS.InlineBulkStatus first. Abort codes for the individual * lookups contained therein are stored in the reply without aborting * the whole operation. */ if (cookie->one_only) goto no_inline_bulk_status; inode = ERR_PTR(-ERESTARTSYS); if (afs_begin_vnode_operation(&fc, dvnode, key, true)) { while (afs_select_fileserver(&fc)) { if (test_bit(AFS_SERVER_FL_NO_IBULK, &fc.cbi->server->flags)) { fc.ac.abort_code = RX_INVALID_OPERATION; fc.ac.error = -ECONNABORTED; break; } iget_data.cb_v_break = dvnode->volume->cb_v_break; iget_data.cb_s_break = fc.cbi->server->cb_s_break; afs_fs_inline_bulk_status(&fc, afs_v2net(dvnode), cookie->fids, cookie->statuses, cookie->nr_fids, NULL); } if (fc.ac.error == 0) cbi = afs_get_cb_interest(fc.cbi); if (fc.ac.abort_code == RX_INVALID_OPERATION) set_bit(AFS_SERVER_FL_NO_IBULK, &fc.cbi->server->flags); inode = ERR_PTR(afs_end_vnode_operation(&fc)); } if (!IS_ERR(inode)) goto success; if (fc.ac.abort_code != RX_INVALID_OPERATION) goto out_c; no_inline_bulk_status: /* 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 just the primary fid. */ inode = ERR_PTR(-ERESTARTSYS); if (afs_begin_vnode_operation(&fc, dvnode, key, true)) { while (afs_select_fileserver(&fc)) { iget_data.cb_v_break = dvnode->volume->cb_v_break; iget_data.cb_s_break = fc.cbi->server->cb_s_break; scb = &cookie->statuses[0]; afs_fs_fetch_status(&fc, afs_v2net(dvnode), cookie->fids, scb, NULL); } if (fc.ac.error == 0) cbi = afs_get_cb_interest(fc.cbi); inode = ERR_PTR(afs_end_vnode_operation(&fc)); } if (IS_ERR(inode)) goto out_c; success: /* Turn all the files into inodes and save the first one - which is the * one we actually want. */ scb = &cookie->statuses[0]; if (scb->status.abort_code != 0) inode = ERR_PTR(afs_abort_to_error(scb->status.abort_code)); for (i = 0; i < cookie->nr_fids; i++) { struct afs_status_cb *scb = &cookie->statuses[i]; if (!scb->have_status && !scb->have_error) continue; if (cookie->inodes[i]) { struct afs_vnode *iv = AFS_FS_I(cookie->inodes[i]); if (test_bit(AFS_VNODE_UNSET, &iv->flags)) continue; afs_vnode_commit_status(&fc, iv, scb->cb_break, NULL, scb); continue; } if (scb->status.abort_code != 0) continue; iget_data.fid = cookie->fids[i]; ti = afs_iget(dir->i_sb, key, &iget_data, scb, cbi, dvnode); if (!IS_ERR(ti)) afs_cache_permit(AFS_FS_I(ti), key, 0 /* Assume vnode->cb_break is 0 */ + iget_data.cb_v_break, scb); if (i == 0) { inode = ti; } else { if (!IS_ERR(ti)) iput(ti); } } out_c: afs_put_cb_interest(afs_v2net(dvnode), cbi); if (cookie->inodes) { for (i = 0; i < cookie->nr_fids; i++) iput(cookie->inodes[i]); kfree(cookie->inodes); } out_s: kvfree(cookie->statuses); out: kfree(cookie); return inode; } /* * 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; 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); } return d; } /* * Check the validity of a dentry under RCU conditions. */ static int afs_d_revalidate_rcu(struct dentry *dentry) { struct afs_vnode *dvnode, *vnode; struct dentry *parent; struct inode *dir, *inode; 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; } /* Check to see if the vnode referred to by the dentry still * has a callback. */ if (d_really_is_positive(dentry)) { inode = d_inode_rcu(dentry); if (inode) { vnode = AFS_FS_I(inode); if (!afs_check_validity(vnode)) 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 uninitialized_var(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; if (d_really_is_positive(dentry)) { inode = d_inode(dentry); if (inode) { vnode = AFS_FS_I(inode); afs_validate(vnode, key); if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) goto out_bad; } } /* lock down the parent dentry so we can peer at it */ parent = dget_parent(dentry); dir = AFS_FS_I(d_inode(parent)); /* validate the parent directory */ afs_validate(dir, key); if (test_bit(AFS_VNODE_DELETED, &dir->flags)) { _debug("%pd: parent dir deleted", dentry); goto out_bad_parent; } /* 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 out_bad_parent; inode = d_inode(dentry); if (is_bad_inode(inode)) { printk("kAFS: afs_d_revalidate: %pd2 has bad inode\n", dentry); goto out_bad_parent; } 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); write_seqlock(&vnode->cb_lock); set_bit(AFS_VNODE_DELETED, &vnode->flags); write_sequnlock(&vnode->cb_lock); goto not_found; } goto out_valid; case -ENOENT: /* the filename is unknown */ _debug("%pd: dirent not found", dentry); if (d_really_is_positive(dentry)) goto not_found; goto out_valid; default: _debug("failed to iterate dir %pd: %d", parent, ret); goto out_bad_parent; } out_valid: dentry->d_fsdata = (void *)(unsigned long)dir_version; out_valid_noupdate: dput(parent); key_put(key); _leave(" = 1 [valid]"); return 1; /* the dirent, if it exists, now points to a different vnode */ not_found: spin_lock(&dentry->d_lock); dentry->d_flags |= DCACHE_NFSFS_RENAMED; spin_unlock(&dentry->d_lock); out_bad_parent: _debug("dropping dentry %pd2", dentry); dput(parent); out_bad: 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); } /* * Create a new inode for create/mkdir/symlink */ static void afs_vnode_new_inode(struct afs_operation *fc, struct dentry *new_dentry, struct afs_iget_data *new_data, struct afs_status_cb *new_scb) { struct afs_vnode *vnode; struct inode *inode; if (fc->ac.error < 0) return; inode = afs_iget(fc->vnode->vfs_inode.i_sb, fc->key, new_data, new_scb, fc->cbi, fc->vnode); if (IS_ERR(inode)) { /* ENOMEM or EINTR at a really inconvenient time - just abandon * the new directory on the server. */ fc->ac.error = PTR_ERR(inode); return; } vnode = AFS_FS_I(inode); set_bit(AFS_VNODE_NEW_CONTENT, &vnode->flags); if (fc->ac.error == 0) afs_cache_permit(vnode, fc->key, vnode->cb_break, new_scb); d_instantiate(new_dentry, inode); } static void afs_prep_for_new_inode(struct afs_operation *fc, struct afs_iget_data *iget_data) { iget_data->volume = fc->vnode->volume; iget_data->cb_v_break = fc->vnode->volume->cb_v_break; iget_data->cb_s_break = fc->cbi->server->cb_s_break; } /* * Note that a dentry got changed. We need to set d_fsdata to the data version * number derived from the result of the operation. It doesn't matter if * d_fsdata goes backwards as we'll just revalidate. */ static void afs_update_dentry_version(struct afs_operation *fc, struct dentry *dentry, struct afs_status_cb *scb) { if (fc->ac.error == 0) dentry->d_fsdata = (void *)(unsigned long)scb->status.data_version; } /* * create a directory on an AFS filesystem */ static int afs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) { struct afs_iget_data iget_data; struct afs_status_cb *scb; struct afs_operation fc; struct afs_vnode *dvnode = AFS_FS_I(dir); struct key *key; afs_dataversion_t data_version; int ret; mode |= S_IFDIR; _enter("{%llx:%llu},{%pd},%ho", dvnode->fid.vid, dvnode->fid.vnode, dentry, mode); ret = -ENOMEM; scb = kcalloc(2, sizeof(struct afs_status_cb), GFP_KERNEL); if (!scb) goto error; key = afs_request_key(dvnode->volume->cell); if (IS_ERR(key)) { ret = PTR_ERR(key); goto error_scb; } ret = -ERESTARTSYS; if (afs_begin_vnode_operation(&fc, dvnode, key, true)) { data_version = dvnode->status.data_version + 1; while (afs_select_fileserver(&fc)) { fc.cb_break = afs_calc_vnode_cb_break(dvnode); afs_prep_for_new_inode(&fc, &iget_data); afs_fs_create(&fc, dentry->d_name.name, mode, &scb[0], &iget_data.fid, &scb[1]); } afs_check_for_remote_deletion(&fc, dvnode); afs_vnode_commit_status(&fc, dvnode, fc.cb_break, &data_version, &scb[0]); afs_update_dentry_version(&fc, dentry, &scb[0]); afs_vnode_new_inode(&fc, dentry, &iget_data, &scb[1]); ret = afs_end_vnode_operation(&fc); if (ret < 0) goto error_key; } else { goto error_key; } if (ret == 0) { down_write(&dvnode->validate_lock); if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags) && dvnode->status.data_version == data_version) afs_edit_dir_add(dvnode, &dentry->d_name, &iget_data.fid, afs_edit_dir_for_create); up_write(&dvnode->validate_lock); } key_put(key); kfree(scb); _leave(" = 0"); return 0; error_key: key_put(key); error_scb: kfree(scb); error: d_drop(dentry); _leave(" = %d", ret); return ret; } /* * 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); } } /* * remove a directory from an AFS filesystem */ static int afs_rmdir(struct inode *dir, struct dentry *dentry) { struct afs_status_cb *scb; struct afs_operation fc; struct afs_vnode *dvnode = AFS_FS_I(dir), *vnode = NULL; struct key *key; afs_dataversion_t data_version; int ret; _enter("{%llx:%llu},{%pd}", dvnode->fid.vid, dvnode->fid.vnode, dentry); scb = kzalloc(sizeof(struct afs_status_cb), GFP_KERNEL); if (!scb) return -ENOMEM; key = afs_request_key(dvnode->volume->cell); if (IS_ERR(key)) { ret = PTR_ERR(key); goto error; } /* 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, key); if (ret < 0) goto error_key; } if (vnode) { ret = down_write_killable(&vnode->rmdir_lock); if (ret < 0) goto error_key; } ret = -ERESTARTSYS; if (afs_begin_vnode_operation(&fc, dvnode, key, true)) { data_version = dvnode->status.data_version + 1; while (afs_select_fileserver(&fc)) { fc.cb_break = afs_calc_vnode_cb_break(dvnode); afs_fs_remove(&fc, vnode, dentry->d_name.name, true, scb); } afs_vnode_commit_status(&fc, dvnode, fc.cb_break, &data_version, scb); afs_update_dentry_version(&fc, dentry, scb); ret = afs_end_vnode_operation(&fc); if (ret == 0) { afs_dir_remove_subdir(dentry); down_write(&dvnode->validate_lock); if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags) && dvnode->status.data_version == data_version) afs_edit_dir_remove(dvnode, &dentry->d_name, afs_edit_dir_for_rmdir); up_write(&dvnode->validate_lock); } } if (vnode) up_write(&vnode->rmdir_lock); error_key: key_put(key); error: kfree(scb); return ret; } /* * 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 int afs_dir_remove_link(struct afs_vnode *dvnode, struct dentry *dentry, struct key *key) { int ret = 0; if (d_really_is_positive(dentry)) { struct afs_vnode *vnode = AFS_FS_I(d_inode(dentry)); 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); ret = 0; } else { afs_break_callback(vnode, afs_cb_break_for_unlink); if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) kdebug("AFS_VNODE_DELETED"); ret = afs_validate(vnode, key); if (ret == -ESTALE) ret = 0; } _debug("nlink %d [val %d]", vnode->vfs_inode.i_nlink, ret); } return ret; } /* * Remove a file or symlink from an AFS filesystem. */ static int afs_unlink(struct inode *dir, struct dentry *dentry) { struct afs_operation fc; struct afs_status_cb *scb; struct afs_vnode *dvnode = AFS_FS_I(dir); struct afs_vnode *vnode = AFS_FS_I(d_inode(dentry)); struct key *key; bool need_rehash = false; int ret; _enter("{%llx:%llu},{%pd}", dvnode->fid.vid, dvnode->fid.vnode, dentry); if (dentry->d_name.len >= AFSNAMEMAX) return -ENAMETOOLONG; ret = -ENOMEM; scb = kcalloc(2, sizeof(struct afs_status_cb), GFP_KERNEL); if (!scb) goto error; key = afs_request_key(dvnode->volume->cell); if (IS_ERR(key)) { ret = PTR_ERR(key); goto error_scb; } /* Try to make sure we have a callback promise on the victim. */ ret = afs_validate(vnode, key); if (ret < 0) goto error_key; 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); ret = afs_sillyrename(dvnode, vnode, dentry, key); goto error_key; } if (!d_unhashed(dentry)) { /* Prevent a race with RCU lookup. */ __d_drop(dentry); need_rehash = true; } spin_unlock(&dentry->d_lock); ret = -ERESTARTSYS; if (afs_begin_vnode_operation(&fc, dvnode, key, true)) { afs_dataversion_t data_version = dvnode->status.data_version + 1; afs_dataversion_t data_version_2 = vnode->status.data_version; while (afs_select_fileserver(&fc)) { fc.cb_break = afs_calc_vnode_cb_break(dvnode); fc.cb_break_2 = afs_calc_vnode_cb_break(vnode); if (test_bit(AFS_SERVER_FL_IS_YFS, &fc.cbi->server->flags) && !test_bit(AFS_SERVER_FL_NO_RM2, &fc.cbi->server->flags)) { yfs_fs_remove_file2(&fc, vnode, dentry->d_name.name, &scb[0], &scb[1]); if (fc.ac.error != -ECONNABORTED || fc.ac.abort_code != RXGEN_OPCODE) continue; set_bit(AFS_SERVER_FL_NO_RM2, &fc.cbi->server->flags); } afs_fs_remove(&fc, vnode, dentry->d_name.name, false, &scb[0]); } afs_vnode_commit_status(&fc, dvnode, fc.cb_break, &data_version, &scb[0]); afs_vnode_commit_status(&fc, vnode, fc.cb_break_2, &data_version_2, &scb[1]); afs_update_dentry_version(&fc, dentry, &scb[0]); ret = afs_end_vnode_operation(&fc); if (ret == 0 && !(scb[1].have_status || scb[1].have_error)) ret = afs_dir_remove_link(dvnode, dentry, key); if (ret == 0) { down_write(&dvnode->validate_lock); if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags) && dvnode->status.data_version == data_version) afs_edit_dir_remove(dvnode, &dentry->d_name, afs_edit_dir_for_unlink); up_write(&dvnode->validate_lock); } } if (need_rehash && ret < 0 && ret != -ENOENT) d_rehash(dentry); error_key: key_put(key); error_scb: kfree(scb); error: _leave(" = %d", ret); return ret; } /* * create a regular file on an AFS filesystem */ static int afs_create(struct inode *dir, struct dentry *dentry, umode_t mode, bool excl) { struct afs_iget_data iget_data; struct afs_operation fc; struct afs_status_cb *scb; struct afs_vnode *dvnode = AFS_FS_I(dir); struct key *key; afs_dataversion_t data_version; int ret; mode |= S_IFREG; _enter("{%llx:%llu},{%pd},%ho,", dvnode->fid.vid, dvnode->fid.vnode, dentry, mode); ret = -ENAMETOOLONG; if (dentry->d_name.len >= AFSNAMEMAX) goto error; key = afs_request_key(dvnode->volume->cell); if (IS_ERR(key)) { ret = PTR_ERR(key); goto error; } ret = -ENOMEM; scb = kcalloc(2, sizeof(struct afs_status_cb), GFP_KERNEL); if (!scb) goto error_scb; ret = -ERESTARTSYS; if (afs_begin_vnode_operation(&fc, dvnode, key, true)) { data_version = dvnode->status.data_version + 1; while (afs_select_fileserver(&fc)) { fc.cb_break = afs_calc_vnode_cb_break(dvnode); afs_prep_for_new_inode(&fc, &iget_data); afs_fs_create(&fc, dentry->d_name.name, mode, &scb[0], &iget_data.fid, &scb[1]); } afs_check_for_remote_deletion(&fc, dvnode); afs_vnode_commit_status(&fc, dvnode, fc.cb_break, &data_version, &scb[0]); afs_update_dentry_version(&fc, dentry, &scb[0]); afs_vnode_new_inode(&fc, dentry, &iget_data, &scb[1]); ret = afs_end_vnode_operation(&fc); if (ret < 0) goto error_key; } else { goto error_key; } down_write(&dvnode->validate_lock); if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags) && dvnode->status.data_version == data_version) afs_edit_dir_add(dvnode, &dentry->d_name, &iget_data.fid, afs_edit_dir_for_create); up_write(&dvnode->validate_lock); kfree(scb); key_put(key); _leave(" = 0"); return 0; error_scb: kfree(scb); error_key: key_put(key); error: d_drop(dentry); _leave(" = %d", ret); return ret; } /* * create a hard link between files in an AFS filesystem */ static int afs_link(struct dentry *from, struct inode *dir, struct dentry *dentry) { struct afs_operation fc; struct afs_status_cb *scb; struct afs_vnode *dvnode = AFS_FS_I(dir); struct afs_vnode *vnode = AFS_FS_I(d_inode(from)); struct key *key; afs_dataversion_t data_version; int ret; _enter("{%llx:%llu},{%llx:%llu},{%pd}", vnode->fid.vid, vnode->fid.vnode, dvnode->fid.vid, dvnode->fid.vnode, dentry); ret = -ENAMETOOLONG; if (dentry->d_name.len >= AFSNAMEMAX) goto error; ret = -ENOMEM; scb = kcalloc(2, sizeof(struct afs_status_cb), GFP_KERNEL); if (!scb) goto error; key = afs_request_key(dvnode->volume->cell); if (IS_ERR(key)) { ret = PTR_ERR(key); goto error_scb; } ret = -ERESTARTSYS; if (afs_begin_vnode_operation(&fc, dvnode, key, true)) { data_version = dvnode->status.data_version + 1; if (mutex_lock_interruptible_nested(&vnode->io_lock, 1) < 0) { afs_end_vnode_operation(&fc); goto error_key; } while (afs_select_fileserver(&fc)) { fc.cb_break = afs_calc_vnode_cb_break(dvnode); fc.cb_break_2 = afs_calc_vnode_cb_break(vnode); afs_fs_link(&fc, vnode, dentry->d_name.name, &scb[0], &scb[1]); } afs_vnode_commit_status(&fc, dvnode, fc.cb_break, &data_version, &scb[0]); afs_vnode_commit_status(&fc, vnode, fc.cb_break_2, NULL, &scb[1]); ihold(&vnode->vfs_inode); afs_update_dentry_version(&fc, dentry, &scb[0]); d_instantiate(dentry, &vnode->vfs_inode); mutex_unlock(&vnode->io_lock); ret = afs_end_vnode_operation(&fc); if (ret < 0) goto error_key; } else { goto error_key; } down_write(&dvnode->validate_lock); if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags) && dvnode->status.data_version == data_version) afs_edit_dir_add(dvnode, &dentry->d_name, &vnode->fid, afs_edit_dir_for_link); up_write(&dvnode->validate_lock); key_put(key); kfree(scb); _leave(" = 0"); return 0; error_key: key_put(key); error_scb: kfree(scb); error: d_drop(dentry); _leave(" = %d", ret); return ret; } /* * create a symlink in an AFS filesystem */ static int afs_symlink(struct inode *dir, struct dentry *dentry, const char *content) { struct afs_iget_data iget_data; struct afs_operation fc; struct afs_status_cb *scb; struct afs_vnode *dvnode = AFS_FS_I(dir); struct key *key; afs_dataversion_t data_version; 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; ret = -ENOMEM; scb = kcalloc(2, sizeof(struct afs_status_cb), GFP_KERNEL); if (!scb) goto error; key = afs_request_key(dvnode->volume->cell); if (IS_ERR(key)) { ret = PTR_ERR(key); goto error_scb; } ret = -ERESTARTSYS; if (afs_begin_vnode_operation(&fc, dvnode, key, true)) { data_version = dvnode->status.data_version + 1; while (afs_select_fileserver(&fc)) { fc.cb_break = afs_calc_vnode_cb_break(dvnode); afs_prep_for_new_inode(&fc, &iget_data); afs_fs_symlink(&fc, dentry->d_name.name, content, &scb[0], &iget_data.fid, &scb[1]); } afs_check_for_remote_deletion(&fc, dvnode); afs_vnode_commit_status(&fc, dvnode, fc.cb_break, &data_version, &scb[0]); afs_update_dentry_version(&fc, dentry, &scb[0]); afs_vnode_new_inode(&fc, dentry, &iget_data, &scb[1]); ret = afs_end_vnode_operation(&fc); if (ret < 0) goto error_key; } else { goto error_key; } down_write(&dvnode->validate_lock); if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags) && dvnode->status.data_version == data_version) afs_edit_dir_add(dvnode, &dentry->d_name, &iget_data.fid, afs_edit_dir_for_symlink); up_write(&dvnode->validate_lock); key_put(key); kfree(scb); _leave(" = 0"); return 0; error_key: key_put(key); error_scb: kfree(scb); error: d_drop(dentry); _leave(" = %d", ret); return ret; } /* * rename a file in an AFS filesystem and/or move it between directories */ static int afs_rename(struct inode *old_dir, struct dentry *old_dentry, struct inode *new_dir, struct dentry *new_dentry, unsigned int flags) { struct afs_operation fc; struct afs_status_cb *scb; struct afs_vnode *orig_dvnode, *new_dvnode, *vnode; struct dentry *tmp = NULL, *rehash = NULL; struct inode *new_inode; struct key *key; afs_dataversion_t orig_data_version; afs_dataversion_t new_data_version; bool new_negative = d_is_negative(new_dentry); 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); ret = -ENOMEM; scb = kcalloc(2, sizeof(struct afs_status_cb), GFP_KERNEL); if (!scb) goto error; key = afs_request_key(orig_dvnode->volume->cell); if (IS_ERR(key)) { ret = PTR_ERR(key); goto error_scb; } /* 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); rehash = new_dentry; } if (d_count(new_dentry) > 2) { /* copy the target dentry's name */ ret = -ENOMEM; tmp = d_alloc(new_dentry->d_parent, &new_dentry->d_name); if (!tmp) goto error_rehash; ret = afs_sillyrename(new_dvnode, AFS_FS_I(d_inode(new_dentry)), new_dentry, key); if (ret) goto error_rehash; new_dentry = tmp; rehash = NULL; 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); ret = -ERESTARTSYS; if (afs_begin_vnode_operation(&fc, orig_dvnode, key, true)) { orig_data_version = orig_dvnode->status.data_version + 1; if (orig_dvnode != new_dvnode) { if (mutex_lock_interruptible_nested(&new_dvnode->io_lock, 1) < 0) { afs_end_vnode_operation(&fc); goto error_rehash_old; } new_data_version = new_dvnode->status.data_version + 1; } else { new_data_version = orig_data_version; } while (afs_select_fileserver(&fc)) { fc.cb_break = afs_calc_vnode_cb_break(orig_dvnode); fc.cb_break_2 = afs_calc_vnode_cb_break(new_dvnode); afs_fs_rename(&fc, old_dentry->d_name.name, new_dvnode, new_dentry->d_name.name, &scb[0], &scb[1]); } afs_vnode_commit_status(&fc, orig_dvnode, fc.cb_break, &orig_data_version, &scb[0]); if (new_dvnode != orig_dvnode) { afs_vnode_commit_status(&fc, new_dvnode, fc.cb_break_2, &new_data_version, &scb[1]); mutex_unlock(&new_dvnode->io_lock); } ret = afs_end_vnode_operation(&fc); if (ret < 0) goto error_rehash_old; } if (ret == 0) { if (rehash) d_rehash(rehash); down_write(&orig_dvnode->validate_lock); if (test_bit(AFS_VNODE_DIR_VALID, &orig_dvnode->flags) && orig_dvnode->status.data_version == orig_data_version) afs_edit_dir_remove(orig_dvnode, &old_dentry->d_name, afs_edit_dir_for_rename_0); if (orig_dvnode != new_dvnode) { up_write(&orig_dvnode->validate_lock); down_write(&new_dvnode->validate_lock); } if (test_bit(AFS_VNODE_DIR_VALID, &new_dvnode->flags) && orig_dvnode->status.data_version == new_data_version) { if (!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 (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(&fc, old_dentry, &scb[1]); afs_update_dentry_version(&fc, new_dentry, &scb[1]); d_move(old_dentry, new_dentry); up_write(&new_dvnode->validate_lock); goto error_tmp; } error_rehash_old: d_rehash(new_dentry); error_rehash: if (rehash) d_rehash(rehash); error_tmp: if (tmp) dput(tmp); key_put(key); error_scb: kfree(scb); error: _leave(" = %d", ret); return ret; } /* * 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); set_page_private(page, 0); ClearPagePrivate(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) { set_page_private(page, 0); ClearPagePrivate(page); } }