diff options
Diffstat (limited to 'kernel/fs/afs/dir.c')
| -rw-r--r-- | kernel/fs/afs/dir.c | 1123 |
1 files changed, 1123 insertions, 0 deletions
diff --git a/kernel/fs/afs/dir.c b/kernel/fs/afs/dir.c new file mode 100644 index 000000000..e10e17788 --- /dev/null +++ b/kernel/fs/afs/dir.c @@ -0,0 +1,1123 @@ +/* dir.c: AFS filesystem directory handling + * + * Copyright (C) 2002 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/fs.h> +#include <linux/namei.h> +#include <linux/pagemap.h> +#include <linux/ctype.h> +#include <linux/sched.h> +#include "internal.h" + +static struct dentry *afs_lookup(struct inode *dir, struct dentry *dentry, + unsigned int flags); +static int afs_dir_open(struct inode *inode, struct file *file); +static int afs_readdir(struct file *file, struct dir_context *ctx); +static int afs_d_revalidate(struct dentry *dentry, unsigned int flags); +static int afs_d_delete(const struct dentry *dentry); +static void afs_d_release(struct dentry *dentry); +static int afs_lookup_filldir(struct dir_context *ctx, const char *name, int nlen, + loff_t fpos, u64 ino, unsigned dtype); +static int afs_create(struct inode *dir, struct dentry *dentry, umode_t mode, + bool excl); +static int afs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode); +static int afs_rmdir(struct inode *dir, struct dentry *dentry); +static int afs_unlink(struct inode *dir, struct dentry *dentry); +static int afs_link(struct dentry *from, struct inode *dir, + struct dentry *dentry); +static int afs_symlink(struct inode *dir, struct dentry *dentry, + const char *content); +static int afs_rename(struct inode *old_dir, struct dentry *old_dentry, + struct inode *new_dir, struct dentry *new_dentry); + +const struct file_operations afs_dir_file_operations = { + .open = afs_dir_open, + .release = afs_release, + .iterate = afs_readdir, + .lock = afs_lock, + .llseek = generic_file_llseek, +}; + +const struct inode_operations afs_dir_inode_operations = { + .create = afs_create, + .lookup = afs_lookup, + .link = afs_link, + .unlink = afs_unlink, + .symlink = afs_symlink, + .mkdir = afs_mkdir, + .rmdir = afs_rmdir, + .rename = afs_rename, + .permission = afs_permission, + .getattr = afs_getattr, + .setattr = afs_setattr, +}; + +const struct dentry_operations afs_fs_dentry_operations = { + .d_revalidate = afs_d_revalidate, + .d_delete = afs_d_delete, + .d_release = afs_d_release, + .d_automount = afs_d_automount, +}; + +#define AFS_DIR_HASHTBL_SIZE 128 +#define AFS_DIR_DIRENT_SIZE 32 +#define AFS_DIRENT_PER_BLOCK 64 + +union afs_dirent { + struct { + uint8_t valid; + uint8_t unused[1]; + __be16 hash_next; + __be32 vnode; + __be32 unique; + uint8_t name[16]; + uint8_t overflow[4]; /* if any char of the name (inc + * NUL) reaches here, consume + * the next dirent too */ + } u; + uint8_t extended_name[32]; +}; + +/* AFS directory page header (one at the beginning of every 2048-byte chunk) */ +struct afs_dir_pagehdr { + __be16 npages; + __be16 magic; +#define AFS_DIR_MAGIC htons(1234) + uint8_t nentries; + uint8_t bitmap[8]; + uint8_t pad[19]; +}; + +/* directory block layout */ +union afs_dir_block { + + struct afs_dir_pagehdr pagehdr; + + struct { + struct afs_dir_pagehdr pagehdr; + uint8_t alloc_ctrs[128]; + /* dir hash table */ + uint16_t hashtable[AFS_DIR_HASHTBL_SIZE]; + } hdr; + + union afs_dirent dirents[AFS_DIRENT_PER_BLOCK]; +}; + +/* layout on a linux VM page */ +struct afs_dir_page { + union afs_dir_block blocks[PAGE_SIZE / sizeof(union afs_dir_block)]; +}; + +struct afs_lookup_cookie { + struct dir_context ctx; + struct afs_fid fid; + struct qstr name; + int found; +}; + +/* + * check that a directory page is valid + */ +static inline void afs_dir_check_page(struct inode *dir, struct page *page) +{ + struct afs_dir_page *dbuf; + loff_t latter; + int tmp, qty; + +#if 0 + /* check the page count */ + qty = desc.size / sizeof(dbuf->blocks[0]); + if (qty == 0) + goto error; + + if (page->index == 0 && qty != ntohs(dbuf->blocks[0].pagehdr.npages)) { + printk("kAFS: %s(%lu): wrong number of dir blocks %d!=%hu\n", + __func__, dir->i_ino, qty, + ntohs(dbuf->blocks[0].pagehdr.npages)); + goto error; + } +#endif + + /* determine how many magic numbers there should be in this page */ + latter = dir->i_size - page_offset(page); + if (latter >= PAGE_SIZE) + qty = PAGE_SIZE; + else + qty = latter; + qty /= sizeof(union afs_dir_block); + + /* check them */ + dbuf = page_address(page); + for (tmp = 0; tmp < qty; tmp++) { + if (dbuf->blocks[tmp].pagehdr.magic != AFS_DIR_MAGIC) { + printk("kAFS: %s(%lu): bad magic %d/%d is %04hx\n", + __func__, dir->i_ino, tmp, qty, + ntohs(dbuf->blocks[tmp].pagehdr.magic)); + goto error; + } + } + + SetPageChecked(page); + return; + +error: + SetPageChecked(page); + SetPageError(page); +} + +/* + * discard a page cached in the pagecache + */ +static inline void afs_dir_put_page(struct page *page) +{ + kunmap(page); + page_cache_release(page); +} + +/* + * get a page into the pagecache + */ +static struct page *afs_dir_get_page(struct inode *dir, unsigned long index, + struct key *key) +{ + struct page *page; + _enter("{%lu},%lu", dir->i_ino, index); + + page = read_cache_page(dir->i_mapping, index, afs_page_filler, key); + if (!IS_ERR(page)) { + kmap(page); + if (!PageChecked(page)) + afs_dir_check_page(dir, page); + if (PageError(page)) + goto fail; + } + return page; + +fail: + afs_dir_put_page(page); + _leave(" = -EIO"); + return ERR_PTR(-EIO); +} + +/* + * open an AFS directory file + */ +static int afs_dir_open(struct inode *inode, struct file *file) +{ + _enter("{%lu}", inode->i_ino); + + BUILD_BUG_ON(sizeof(union afs_dir_block) != 2048); + BUILD_BUG_ON(sizeof(union afs_dirent) != 32); + + if (test_bit(AFS_VNODE_DELETED, &AFS_FS_I(inode)->flags)) + return -ENOENT; + + return afs_open(inode, file); +} + +/* + * deal with one block in an AFS directory + */ +static int afs_dir_iterate_block(struct dir_context *ctx, + union afs_dir_block *block, + unsigned blkoff) +{ + union afs_dirent *dire; + unsigned offset, next, curr; + size_t nlen; + int tmp; + + _enter("%u,%x,%p,,",(unsigned)ctx->pos,blkoff,block); + + curr = (ctx->pos - blkoff) / sizeof(union afs_dirent); + + /* walk through the block, an entry at a time */ + for (offset = AFS_DIRENT_PER_BLOCK - block->pagehdr.nentries; + offset < AFS_DIRENT_PER_BLOCK; + offset = next + ) { + next = offset + 1; + + /* skip entries marked unused in the bitmap */ + if (!(block->pagehdr.bitmap[offset / 8] & + (1 << (offset % 8)))) { + _debug("ENT[%Zu.%u]: unused", + blkoff / sizeof(union afs_dir_block), offset); + if (offset >= curr) + ctx->pos = blkoff + + next * sizeof(union afs_dirent); + continue; + } + + /* got a valid entry */ + dire = &block->dirents[offset]; + nlen = strnlen(dire->u.name, + sizeof(*block) - + offset * sizeof(union afs_dirent)); + + _debug("ENT[%Zu.%u]: %s %Zu \"%s\"", + blkoff / sizeof(union afs_dir_block), offset, + (offset < curr ? "skip" : "fill"), + nlen, dire->u.name); + + /* work out where the next possible entry is */ + for (tmp = nlen; tmp > 15; tmp -= sizeof(union afs_dirent)) { + if (next >= AFS_DIRENT_PER_BLOCK) { + _debug("ENT[%Zu.%u]:" + " %u travelled beyond end dir block" + " (len %u/%Zu)", + blkoff / sizeof(union afs_dir_block), + offset, next, tmp, nlen); + return -EIO; + } + if (!(block->pagehdr.bitmap[next / 8] & + (1 << (next % 8)))) { + _debug("ENT[%Zu.%u]:" + " %u unmarked extension (len %u/%Zu)", + blkoff / sizeof(union afs_dir_block), + offset, next, tmp, nlen); + return -EIO; + } + + _debug("ENT[%Zu.%u]: ext %u/%Zu", + blkoff / sizeof(union afs_dir_block), + next, tmp, nlen); + next++; + } + + /* skip if starts before the current position */ + if (offset < curr) + continue; + + /* found the next entry */ + if (!dir_emit(ctx, dire->u.name, nlen, + ntohl(dire->u.vnode), + ctx->actor == afs_lookup_filldir ? + ntohl(dire->u.unique) : DT_UNKNOWN)) { + _leave(" = 0 [full]"); + return 0; + } + + ctx->pos = blkoff + next * sizeof(union afs_dirent); + } + + _leave(" = 1 [more]"); + return 1; +} + +/* + * iterate through the data blob that lists the contents of an AFS directory + */ +static int afs_dir_iterate(struct inode *dir, struct dir_context *ctx, + struct key *key) +{ + union afs_dir_block *dblock; + struct afs_dir_page *dbuf; + struct page *page; + unsigned blkoff, limit; + int ret; + + _enter("{%lu},%u,,", dir->i_ino, (unsigned)ctx->pos); + + if (test_bit(AFS_VNODE_DELETED, &AFS_FS_I(dir)->flags)) { + _leave(" = -ESTALE"); + return -ESTALE; + } + + /* round the file position up to the next entry boundary */ + ctx->pos += sizeof(union afs_dirent) - 1; + ctx->pos &= ~(sizeof(union afs_dirent) - 1); + + /* walk through the blocks in sequence */ + ret = 0; + while (ctx->pos < dir->i_size) { + blkoff = ctx->pos & ~(sizeof(union afs_dir_block) - 1); + + /* fetch the appropriate page from the directory */ + page = afs_dir_get_page(dir, blkoff / PAGE_SIZE, key); + if (IS_ERR(page)) { + ret = PTR_ERR(page); + break; + } + + limit = blkoff & ~(PAGE_SIZE - 1); + + dbuf = page_address(page); + + /* deal with the individual blocks stashed on this page */ + do { + dblock = &dbuf->blocks[(blkoff % PAGE_SIZE) / + sizeof(union afs_dir_block)]; + ret = afs_dir_iterate_block(ctx, dblock, blkoff); + if (ret != 1) { + afs_dir_put_page(page); + goto out; + } + + blkoff += sizeof(union afs_dir_block); + + } while (ctx->pos < dir->i_size && blkoff < limit); + + afs_dir_put_page(page); + ret = 0; + } + +out: + _leave(" = %d", ret); + return ret; +} + +/* + * read an AFS directory + */ +static int afs_readdir(struct file *file, struct dir_context *ctx) +{ + return afs_dir_iterate(file_inode(file), + ctx, file->private_data); +} + +/* + * search the directory for a name + * - if afs_dir_iterate_block() spots this function, it'll pass the FID + * uniquifier through dtype + */ +static int afs_lookup_filldir(struct dir_context *ctx, const char *name, + int nlen, loff_t fpos, u64 ino, unsigned dtype) +{ + struct afs_lookup_cookie *cookie = + container_of(ctx, struct afs_lookup_cookie, ctx); + + _enter("{%s,%u},%s,%u,,%llu,%u", + cookie->name.name, cookie->name.len, name, nlen, + (unsigned long long) ino, dtype); + + /* insanity checks first */ + BUILD_BUG_ON(sizeof(union afs_dir_block) != 2048); + BUILD_BUG_ON(sizeof(union afs_dirent) != 32); + + if (cookie->name.len != nlen || + memcmp(cookie->name.name, name, nlen) != 0) { + _leave(" = 0 [no]"); + return 0; + } + + cookie->fid.vnode = ino; + cookie->fid.unique = dtype; + cookie->found = 1; + + _leave(" = -1 [found]"); + return -1; +} + +/* + * do a lookup in a directory + * - just returns the FID the dentry name maps to if found + */ +static int afs_do_lookup(struct inode *dir, struct dentry *dentry, + struct afs_fid *fid, struct key *key) +{ + struct afs_super_info *as = dir->i_sb->s_fs_info; + struct afs_lookup_cookie cookie = { + .ctx.actor = afs_lookup_filldir, + .name = dentry->d_name, + .fid.vid = as->volume->vid + }; + int ret; + + _enter("{%lu},%p{%pd},", dir->i_ino, dentry, dentry); + + /* search the directory */ + ret = afs_dir_iterate(dir, &cookie.ctx, key); + if (ret < 0) { + _leave(" = %d [iter]", ret); + return ret; + } + + ret = -ENOENT; + if (!cookie.found) { + _leave(" = -ENOENT [not found]"); + return -ENOENT; + } + + *fid = cookie.fid; + _leave(" = 0 { vn=%u u=%u }", fid->vnode, fid->unique); + return 0; +} + +/* + * Try to auto mount the mountpoint with pseudo directory, if the autocell + * operation is setted. + */ +static struct inode *afs_try_auto_mntpt( + int ret, struct dentry *dentry, struct inode *dir, struct key *key, + struct afs_fid *fid) +{ + const char *devname = dentry->d_name.name; + struct afs_vnode *vnode = AFS_FS_I(dir); + struct inode *inode; + + _enter("%d, %p{%pd}, {%x:%u}, %p", + ret, dentry, dentry, vnode->fid.vid, vnode->fid.vnode, key); + + if (ret != -ENOENT || + !test_bit(AFS_VNODE_AUTOCELL, &vnode->flags)) + goto out; + + inode = afs_iget_autocell(dir, devname, strlen(devname), key); + if (IS_ERR(inode)) { + ret = PTR_ERR(inode); + goto out; + } + + *fid = AFS_FS_I(inode)->fid; + _leave("= %p", inode); + return inode; + +out: + _leave("= %d", ret); + return ERR_PTR(ret); +} + +/* + * look up an entry in a directory + */ +static struct dentry *afs_lookup(struct inode *dir, struct dentry *dentry, + unsigned int flags) +{ + struct afs_vnode *vnode; + struct afs_fid fid; + struct inode *inode; + struct key *key; + int ret; + + vnode = AFS_FS_I(dir); + + _enter("{%x:%u},%p{%pd},", + vnode->fid.vid, vnode->fid.vnode, dentry, dentry); + + ASSERTCMP(d_inode(dentry), ==, NULL); + + if (dentry->d_name.len >= AFSNAMEMAX) { + _leave(" = -ENAMETOOLONG"); + return ERR_PTR(-ENAMETOOLONG); + } + + if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) { + _leave(" = -ESTALE"); + return ERR_PTR(-ESTALE); + } + + key = afs_request_key(vnode->volume->cell); + if (IS_ERR(key)) { + _leave(" = %ld [key]", PTR_ERR(key)); + return ERR_CAST(key); + } + + ret = afs_validate(vnode, key); + if (ret < 0) { + key_put(key); + _leave(" = %d [val]", ret); + return ERR_PTR(ret); + } + + ret = afs_do_lookup(dir, dentry, &fid, key); + if (ret < 0) { + inode = afs_try_auto_mntpt(ret, dentry, dir, key, &fid); + if (!IS_ERR(inode)) { + key_put(key); + goto success; + } + + ret = PTR_ERR(inode); + key_put(key); + if (ret == -ENOENT) { + d_add(dentry, NULL); + _leave(" = NULL [negative]"); + return NULL; + } + _leave(" = %d [do]", ret); + return ERR_PTR(ret); + } + dentry->d_fsdata = (void *)(unsigned long) vnode->status.data_version; + + /* instantiate the dentry */ + inode = afs_iget(dir->i_sb, key, &fid, NULL, NULL); + key_put(key); + if (IS_ERR(inode)) { + _leave(" = %ld", PTR_ERR(inode)); + return ERR_CAST(inode); + } + +success: + d_add(dentry, inode); + _leave(" = 0 { vn=%u u=%u } -> { ino=%lu v=%u }", + fid.vnode, + fid.unique, + d_inode(dentry)->i_ino, + d_inode(dentry)->i_generation); + + return NULL; +} + +/* + * check that a dentry lookup hit has found a valid entry + * - NOTE! the hit can be a negative hit too, so we can't assume we have an + * inode + */ +static int afs_d_revalidate(struct dentry *dentry, unsigned int flags) +{ + struct afs_vnode *vnode, *dir; + struct afs_fid uninitialized_var(fid); + struct dentry *parent; + struct key *key; + void *dir_version; + int ret; + + if (flags & LOOKUP_RCU) + return -ECHILD; + + vnode = AFS_FS_I(d_inode(dentry)); + + if (d_really_is_positive(dentry)) + _enter("{v={%x:%u} n=%pd fl=%lx},", + vnode->fid.vid, vnode->fid.vnode, dentry, + vnode->flags); + else + _enter("{neg n=%pd}", dentry); + + key = afs_request_key(AFS_FS_S(dentry->d_sb)->volume->cell); + if (IS_ERR(key)) + key = NULL; + + /* lock down the parent dentry so we can peer at it */ + parent = dget_parent(dentry); + dir = AFS_FS_I(d_inode(parent)); + + /* validate the parent directory */ + if (test_bit(AFS_VNODE_MODIFIED, &dir->flags)) + afs_validate(dir, key); + + if (test_bit(AFS_VNODE_DELETED, &dir->flags)) { + _debug("%pd: parent dir deleted", dentry); + goto out_bad; + } + + dir_version = (void *) (unsigned long) dir->status.data_version; + if (dentry->d_fsdata == dir_version) + goto out_valid; /* the dir contents are unchanged */ + + _debug("dir modified"); + + /* search the directory for this vnode */ + ret = afs_do_lookup(&dir->vfs_inode, dentry, &fid, key); + switch (ret) { + case 0: + /* the filename maps to something */ + if (d_really_is_negative(dentry)) + goto out_bad; + if (is_bad_inode(d_inode(dentry))) { + printk("kAFS: afs_d_revalidate: %pd2 has bad inode\n", + dentry); + goto out_bad; + } + + /* if the vnode ID has changed, then the dirent points to a + * different file */ + if (fid.vnode != vnode->fid.vnode) { + _debug("%pd: dirent changed [%u != %u]", + dentry, fid.vnode, + vnode->fid.vnode); + goto not_found; + } + + /* if the vnode ID uniqifier has changed, then the file has + * been deleted and replaced, and the original vnode ID has + * been reused */ + if (fid.unique != vnode->fid.unique) { + _debug("%pd: file deleted (uq %u -> %u I:%u)", + dentry, fid.unique, + vnode->fid.unique, + d_inode(dentry)->i_generation); + spin_lock(&vnode->lock); + set_bit(AFS_VNODE_DELETED, &vnode->flags); + spin_unlock(&vnode->lock); + goto not_found; + } + goto out_valid; + + case -ENOENT: + /* the filename is unknown */ + _debug("%pd: dirent not found", dentry); + if (d_really_is_positive(dentry)) + goto not_found; + goto out_valid; + + default: + _debug("failed to iterate dir %pd: %d", + parent, ret); + goto out_bad; + } + +out_valid: + dentry->d_fsdata = dir_version; + dput(parent); + key_put(key); + _leave(" = 1 [valid]"); + return 1; + + /* the dirent, if it exists, now points to a different vnode */ +not_found: + spin_lock(&dentry->d_lock); + dentry->d_flags |= DCACHE_NFSFS_RENAMED; + spin_unlock(&dentry->d_lock); + +out_bad: + _debug("dropping dentry %pd2", dentry); + dput(parent); + key_put(key); + + _leave(" = 0 [bad]"); + return 0; +} + +/* + * allow the VFS to enquire as to whether a dentry should be unhashed (mustn't + * sleep) + * - called from dput() when d_count is going to 0. + * - return 1 to request dentry be unhashed, 0 otherwise + */ +static int afs_d_delete(const struct dentry *dentry) +{ + _enter("%pd", dentry); + + if (dentry->d_flags & DCACHE_NFSFS_RENAMED) + goto zap; + + if (d_really_is_positive(dentry) && + (test_bit(AFS_VNODE_DELETED, &AFS_FS_I(d_inode(dentry))->flags) || + test_bit(AFS_VNODE_PSEUDODIR, &AFS_FS_I(d_inode(dentry))->flags))) + goto zap; + + _leave(" = 0 [keep]"); + return 0; + +zap: + _leave(" = 1 [zap]"); + return 1; +} + +/* + * handle dentry release + */ +static void afs_d_release(struct dentry *dentry) +{ + _enter("%pd", dentry); +} + +/* + * create a directory on an AFS filesystem + */ +static int afs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) +{ + struct afs_file_status status; + struct afs_callback cb; + struct afs_server *server; + struct afs_vnode *dvnode, *vnode; + struct afs_fid fid; + struct inode *inode; + struct key *key; + int ret; + + dvnode = AFS_FS_I(dir); + + _enter("{%x:%u},{%pd},%ho", + dvnode->fid.vid, dvnode->fid.vnode, dentry, mode); + + key = afs_request_key(dvnode->volume->cell); + if (IS_ERR(key)) { + ret = PTR_ERR(key); + goto error; + } + + mode |= S_IFDIR; + ret = afs_vnode_create(dvnode, key, dentry->d_name.name, + mode, &fid, &status, &cb, &server); + if (ret < 0) + goto mkdir_error; + + inode = afs_iget(dir->i_sb, key, &fid, &status, &cb); + if (IS_ERR(inode)) { + /* ENOMEM at a really inconvenient time - just abandon the new + * directory on the server */ + ret = PTR_ERR(inode); + goto iget_error; + } + + /* apply the status report we've got for the new vnode */ + vnode = AFS_FS_I(inode); + spin_lock(&vnode->lock); + vnode->update_cnt++; + spin_unlock(&vnode->lock); + afs_vnode_finalise_status_update(vnode, server); + afs_put_server(server); + + d_instantiate(dentry, inode); + if (d_unhashed(dentry)) { + _debug("not hashed"); + d_rehash(dentry); + } + key_put(key); + _leave(" = 0"); + return 0; + +iget_error: + afs_put_server(server); +mkdir_error: + key_put(key); +error: + d_drop(dentry); + _leave(" = %d", ret); + return ret; +} + +/* + * remove a directory from an AFS filesystem + */ +static int afs_rmdir(struct inode *dir, struct dentry *dentry) +{ + struct afs_vnode *dvnode, *vnode; + struct key *key; + int ret; + + dvnode = AFS_FS_I(dir); + + _enter("{%x:%u},{%pd}", + dvnode->fid.vid, dvnode->fid.vnode, dentry); + + key = afs_request_key(dvnode->volume->cell); + if (IS_ERR(key)) { + ret = PTR_ERR(key); + goto error; + } + + ret = afs_vnode_remove(dvnode, key, dentry->d_name.name, true); + if (ret < 0) + goto rmdir_error; + + if (d_really_is_positive(dentry)) { + vnode = AFS_FS_I(d_inode(dentry)); + clear_nlink(&vnode->vfs_inode); + set_bit(AFS_VNODE_DELETED, &vnode->flags); + afs_discard_callback_on_delete(vnode); + } + + key_put(key); + _leave(" = 0"); + return 0; + +rmdir_error: + key_put(key); +error: + _leave(" = %d", ret); + return ret; +} + +/* + * remove a file from an AFS filesystem + */ +static int afs_unlink(struct inode *dir, struct dentry *dentry) +{ + struct afs_vnode *dvnode, *vnode; + struct key *key; + int ret; + + dvnode = AFS_FS_I(dir); + + _enter("{%x:%u},{%pd}", + dvnode->fid.vid, dvnode->fid.vnode, dentry); + + ret = -ENAMETOOLONG; + if (dentry->d_name.len >= AFSNAMEMAX) + goto error; + + key = afs_request_key(dvnode->volume->cell); + if (IS_ERR(key)) { + ret = PTR_ERR(key); + goto error; + } + + if (d_really_is_positive(dentry)) { + vnode = AFS_FS_I(d_inode(dentry)); + + /* make sure we have a callback promise on the victim */ + ret = afs_validate(vnode, key); + if (ret < 0) + goto error; + } + + ret = afs_vnode_remove(dvnode, key, dentry->d_name.name, false); + if (ret < 0) + goto remove_error; + + if (d_really_is_positive(dentry)) { + /* if the file wasn't deleted due to excess hard links, the + * fileserver will break the callback promise on the file - if + * it had one - before it returns to us, and if it was deleted, + * it won't + * + * however, if we didn't have a callback promise outstanding, + * or it was outstanding on a different server, then it won't + * break it either... + */ + vnode = AFS_FS_I(d_inode(dentry)); + if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) + _debug("AFS_VNODE_DELETED"); + if (test_bit(AFS_VNODE_CB_BROKEN, &vnode->flags)) + _debug("AFS_VNODE_CB_BROKEN"); + set_bit(AFS_VNODE_CB_BROKEN, &vnode->flags); + ret = afs_validate(vnode, key); + _debug("nlink %d [val %d]", vnode->vfs_inode.i_nlink, ret); + } + + key_put(key); + _leave(" = 0"); + return 0; + +remove_error: + key_put(key); +error: + _leave(" = %d", ret); + return ret; +} + +/* + * create a regular file on an AFS filesystem + */ +static int afs_create(struct inode *dir, struct dentry *dentry, umode_t mode, + bool excl) +{ + struct afs_file_status status; + struct afs_callback cb; + struct afs_server *server; + struct afs_vnode *dvnode, *vnode; + struct afs_fid fid; + struct inode *inode; + struct key *key; + int ret; + + dvnode = AFS_FS_I(dir); + + _enter("{%x:%u},{%pd},%ho,", + dvnode->fid.vid, dvnode->fid.vnode, dentry, mode); + + key = afs_request_key(dvnode->volume->cell); + if (IS_ERR(key)) { + ret = PTR_ERR(key); + goto error; + } + + mode |= S_IFREG; + ret = afs_vnode_create(dvnode, key, dentry->d_name.name, + mode, &fid, &status, &cb, &server); + if (ret < 0) + goto create_error; + + inode = afs_iget(dir->i_sb, key, &fid, &status, &cb); + if (IS_ERR(inode)) { + /* ENOMEM at a really inconvenient time - just abandon the new + * directory on the server */ + ret = PTR_ERR(inode); + goto iget_error; + } + + /* apply the status report we've got for the new vnode */ + vnode = AFS_FS_I(inode); + spin_lock(&vnode->lock); + vnode->update_cnt++; + spin_unlock(&vnode->lock); + afs_vnode_finalise_status_update(vnode, server); + afs_put_server(server); + + d_instantiate(dentry, inode); + if (d_unhashed(dentry)) { + _debug("not hashed"); + d_rehash(dentry); + } + key_put(key); + _leave(" = 0"); + return 0; + +iget_error: + afs_put_server(server); +create_error: + key_put(key); +error: + d_drop(dentry); + _leave(" = %d", ret); + return ret; +} + +/* + * create a hard link between files in an AFS filesystem + */ +static int afs_link(struct dentry *from, struct inode *dir, + struct dentry *dentry) +{ + struct afs_vnode *dvnode, *vnode; + struct key *key; + int ret; + + vnode = AFS_FS_I(d_inode(from)); + dvnode = AFS_FS_I(dir); + + _enter("{%x:%u},{%x:%u},{%pd}", + vnode->fid.vid, vnode->fid.vnode, + dvnode->fid.vid, dvnode->fid.vnode, + dentry); + + key = afs_request_key(dvnode->volume->cell); + if (IS_ERR(key)) { + ret = PTR_ERR(key); + goto error; + } + + ret = afs_vnode_link(dvnode, vnode, key, dentry->d_name.name); + if (ret < 0) + goto link_error; + + ihold(&vnode->vfs_inode); + d_instantiate(dentry, &vnode->vfs_inode); + key_put(key); + _leave(" = 0"); + return 0; + +link_error: + key_put(key); +error: + d_drop(dentry); + _leave(" = %d", ret); + return ret; +} + +/* + * create a symlink in an AFS filesystem + */ +static int afs_symlink(struct inode *dir, struct dentry *dentry, + const char *content) +{ + struct afs_file_status status; + struct afs_server *server; + struct afs_vnode *dvnode, *vnode; + struct afs_fid fid; + struct inode *inode; + struct key *key; + int ret; + + dvnode = AFS_FS_I(dir); + + _enter("{%x:%u},{%pd},%s", + dvnode->fid.vid, dvnode->fid.vnode, dentry, + content); + + ret = -EINVAL; + if (strlen(content) >= AFSPATHMAX) + goto error; + + key = afs_request_key(dvnode->volume->cell); + if (IS_ERR(key)) { + ret = PTR_ERR(key); + goto error; + } + + ret = afs_vnode_symlink(dvnode, key, dentry->d_name.name, content, + &fid, &status, &server); + if (ret < 0) + goto create_error; + + inode = afs_iget(dir->i_sb, key, &fid, &status, NULL); + if (IS_ERR(inode)) { + /* ENOMEM at a really inconvenient time - just abandon the new + * directory on the server */ + ret = PTR_ERR(inode); + goto iget_error; + } + + /* apply the status report we've got for the new vnode */ + vnode = AFS_FS_I(inode); + spin_lock(&vnode->lock); + vnode->update_cnt++; + spin_unlock(&vnode->lock); + afs_vnode_finalise_status_update(vnode, server); + afs_put_server(server); + + d_instantiate(dentry, inode); + if (d_unhashed(dentry)) { + _debug("not hashed"); + d_rehash(dentry); + } + key_put(key); + _leave(" = 0"); + return 0; + +iget_error: + afs_put_server(server); +create_error: + key_put(key); +error: + d_drop(dentry); + _leave(" = %d", ret); + return ret; +} + +/* + * rename a file in an AFS filesystem and/or move it between directories + */ +static int afs_rename(struct inode *old_dir, struct dentry *old_dentry, + struct inode *new_dir, struct dentry *new_dentry) +{ + struct afs_vnode *orig_dvnode, *new_dvnode, *vnode; + struct key *key; + int ret; + + vnode = AFS_FS_I(d_inode(old_dentry)); + orig_dvnode = AFS_FS_I(old_dir); + new_dvnode = AFS_FS_I(new_dir); + + _enter("{%x:%u},{%x:%u},{%x:%u},{%pd}", + orig_dvnode->fid.vid, orig_dvnode->fid.vnode, + vnode->fid.vid, vnode->fid.vnode, + new_dvnode->fid.vid, new_dvnode->fid.vnode, + new_dentry); + + key = afs_request_key(orig_dvnode->volume->cell); + if (IS_ERR(key)) { + ret = PTR_ERR(key); + goto error; + } + + ret = afs_vnode_rename(orig_dvnode, new_dvnode, key, + old_dentry->d_name.name, + new_dentry->d_name.name); + if (ret < 0) + goto rename_error; + key_put(key); + _leave(" = 0"); + return 0; + +rename_error: + key_put(key); +error: + d_drop(new_dentry); + _leave(" = %d", ret); + return ret; +} |