diff --git a/fs/afs/Makefile b/fs/afs/Makefile index 45b7fc405fa6..6a055423c192 100644 --- a/fs/afs/Makefile +++ b/fs/afs/Makefile @@ -12,6 +12,7 @@ kafs-objs := \ cell.o \ cmservice.o \ dir.o \ + dynroot.o \ file.o \ flock.o \ fsclient.o \ diff --git a/fs/afs/dir.c b/fs/afs/dir.c index 08b499504f63..405ebd609b87 100644 --- a/fs/afs/dir.c +++ b/fs/afs/dir.c @@ -10,25 +10,19 @@ */ #include -#include -#include #include #include #include #include #include -#include #include "internal.h" static struct dentry *afs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags); -static struct dentry *afs_dynroot_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_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, @@ -69,17 +63,6 @@ const struct inode_operations afs_dir_inode_operations = { .listxattr = afs_listxattr, }; -const struct file_operations afs_dynroot_file_operations = { - .open = dcache_dir_open, - .release = dcache_dir_close, - .iterate_shared = dcache_readdir, - .llseek = dcache_dir_lseek, -}; - -const struct inode_operations afs_dynroot_inode_operations = { - .lookup = afs_dynroot_lookup, -}; - const struct dentry_operations afs_fs_dentry_operations = { .d_revalidate = afs_d_revalidate, .d_delete = afs_d_delete, @@ -702,71 +685,6 @@ out: return inode; } -/* - * Probe to see if a cell may exist. This prevents positive dentries from - * being created unnecessarily. - */ -static int afs_probe_cell_name(struct dentry *dentry) -{ - struct afs_cell *cell; - const char *name = dentry->d_name.name; - size_t len = dentry->d_name.len; - int ret; - - /* Names prefixed with a dot are R/W mounts. */ - if (name[0] == '.') { - if (len == 1) - return -EINVAL; - name++; - len--; - } - - cell = afs_lookup_cell_rcu(afs_d2net(dentry), name, len); - if (!IS_ERR(cell)) { - afs_put_cell(afs_d2net(dentry), cell); - return 0; - } - - ret = dns_query("afsdb", name, len, "ipv4", NULL, NULL); - if (ret == -ENODATA) - ret = -EDESTADDRREQ; - return ret; -} - -/* - * Try to auto mount the mountpoint with pseudo directory, if the autocell - * operation is setted. - */ -static struct inode *afs_try_auto_mntpt(struct dentry *dentry, struct inode *dir) -{ - struct afs_vnode *vnode = AFS_FS_I(dir); - struct inode *inode; - int ret = -ENOENT; - - _enter("%p{%pd}, {%x:%u}", - dentry, dentry, vnode->fid.vid, vnode->fid.vnode); - - if (!test_bit(AFS_VNODE_AUTOCELL, &vnode->flags)) - goto out; - - ret = afs_probe_cell_name(dentry); - if (ret < 0) - goto out; - - inode = afs_iget_pseudo_dir(dir->i_sb, false); - if (IS_ERR(inode)) { - ret = PTR_ERR(inode); - goto out; - } - - _leave("= %p", inode); - return inode; - -out: - _leave("= %d", ret); - return ERR_PTR(ret); -} - /* * Look up an entry in a directory with @sys substitution. */ @@ -910,98 +828,6 @@ success: return NULL; } -/* - * Look up @cell in a dynroot directory. This is a substitution for the - * local cell name for the net namespace. - */ -static struct dentry *afs_lookup_atcell(struct dentry *dentry) -{ - struct afs_cell *cell; - struct afs_net *net = afs_d2net(dentry); - struct dentry *ret; - unsigned int seq = 0; - char *name; - int len; - - if (!net->ws_cell) - return ERR_PTR(-ENOENT); - - ret = ERR_PTR(-ENOMEM); - name = kmalloc(AFS_MAXCELLNAME + 1, GFP_KERNEL); - if (!name) - goto out_p; - - rcu_read_lock(); - do { - read_seqbegin_or_lock(&net->cells_lock, &seq); - cell = rcu_dereference_raw(net->ws_cell); - if (cell) { - len = cell->name_len; - memcpy(name, cell->name, len + 1); - } - } while (need_seqretry(&net->cells_lock, seq)); - done_seqretry(&net->cells_lock, seq); - rcu_read_unlock(); - - ret = ERR_PTR(-ENOENT); - if (!cell) - goto out_n; - - ret = lookup_one_len(name, dentry->d_parent, len); - - /* We don't want to d_add() the @cell dentry here as we don't want to - * the cached dentry to hide changes to the local cell name. - */ - -out_n: - kfree(name); -out_p: - return ret; -} - -/* - * Look up an entry in a dynroot directory. - */ -static struct dentry *afs_dynroot_lookup(struct inode *dir, struct dentry *dentry, - unsigned int flags) -{ - struct afs_vnode *vnode; - struct inode *inode; - int ret; - - vnode = AFS_FS_I(dir); - - _enter("%pd", dentry); - - ASSERTCMP(d_inode(dentry), ==, NULL); - - if (dentry->d_name.len >= AFSNAMEMAX) { - _leave(" = -ENAMETOOLONG"); - return ERR_PTR(-ENAMETOOLONG); - } - - if (dentry->d_name.len == 5 && - memcmp(dentry->d_name.name, "@cell", 5) == 0) - return afs_lookup_atcell(dentry); - - inode = afs_try_auto_mntpt(dentry, dir); - if (IS_ERR(inode)) { - ret = PTR_ERR(inode); - if (ret == -ENOENT) { - d_add(dentry, NULL); - _leave(" = NULL [negative]"); - return NULL; - } - _leave(" = %d [do]", ret); - return ERR_PTR(ret); - } - - d_add(dentry, inode); - _leave(" = 0 { ino=%lu v=%u }", - 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 @@ -1009,7 +835,6 @@ static struct dentry *afs_dynroot_lookup(struct inode *dir, struct dentry *dentr */ static int afs_d_revalidate(struct dentry *dentry, unsigned int flags) { - struct afs_super_info *as = dentry->d_sb->s_fs_info; struct afs_vnode *vnode, *dir; struct afs_fid uninitialized_var(fid); struct dentry *parent; @@ -1021,9 +846,6 @@ static int afs_d_revalidate(struct dentry *dentry, unsigned int flags) if (flags & LOOKUP_RCU) return -ECHILD; - if (as->dyn_root) - return 1; - if (d_really_is_positive(dentry)) { vnode = AFS_FS_I(d_inode(dentry)); _enter("{v={%x:%u} n=%pd fl=%lx},", @@ -1181,7 +1003,7 @@ zap: /* * handle dentry release */ -static void afs_d_release(struct dentry *dentry) +void afs_d_release(struct dentry *dentry) { _enter("%pd", dentry); } diff --git a/fs/afs/dynroot.c b/fs/afs/dynroot.c new file mode 100644 index 000000000000..983f3946ab57 --- /dev/null +++ b/fs/afs/dynroot.c @@ -0,0 +1,209 @@ +/* dir.c: AFS dynamic root handling + * + * Copyright (C) 2018 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 Licence + * as published by the Free Software Foundation; either version + * 2 of the Licence, or (at your option) any later version. + */ + +#include +#include +#include +#include "internal.h" + +const struct file_operations afs_dynroot_file_operations = { + .open = dcache_dir_open, + .release = dcache_dir_close, + .iterate_shared = dcache_readdir, + .llseek = dcache_dir_lseek, +}; + +/* + * Probe to see if a cell may exist. This prevents positive dentries from + * being created unnecessarily. + */ +static int afs_probe_cell_name(struct dentry *dentry) +{ + struct afs_cell *cell; + const char *name = dentry->d_name.name; + size_t len = dentry->d_name.len; + int ret; + + /* Names prefixed with a dot are R/W mounts. */ + if (name[0] == '.') { + if (len == 1) + return -EINVAL; + name++; + len--; + } + + cell = afs_lookup_cell_rcu(afs_d2net(dentry), name, len); + if (!IS_ERR(cell)) { + afs_put_cell(afs_d2net(dentry), cell); + return 0; + } + + ret = dns_query("afsdb", name, len, "ipv4", NULL, NULL); + if (ret == -ENODATA) + ret = -EDESTADDRREQ; + return ret; +} + +/* + * Try to auto mount the mountpoint with pseudo directory, if the autocell + * operation is setted. + */ +struct inode *afs_try_auto_mntpt(struct dentry *dentry, struct inode *dir) +{ + struct afs_vnode *vnode = AFS_FS_I(dir); + struct inode *inode; + int ret = -ENOENT; + + _enter("%p{%pd}, {%x:%u}", + dentry, dentry, vnode->fid.vid, vnode->fid.vnode); + + if (!test_bit(AFS_VNODE_AUTOCELL, &vnode->flags)) + goto out; + + ret = afs_probe_cell_name(dentry); + if (ret < 0) + goto out; + + inode = afs_iget_pseudo_dir(dir->i_sb, false); + if (IS_ERR(inode)) { + ret = PTR_ERR(inode); + goto out; + } + + _leave("= %p", inode); + return inode; + +out: + _leave("= %d", ret); + return ERR_PTR(ret); +} + +/* + * Look up @cell in a dynroot directory. This is a substitution for the + * local cell name for the net namespace. + */ +static struct dentry *afs_lookup_atcell(struct dentry *dentry) +{ + struct afs_cell *cell; + struct afs_net *net = afs_d2net(dentry); + struct dentry *ret; + unsigned int seq = 0; + char *name; + int len; + + if (!net->ws_cell) + return ERR_PTR(-ENOENT); + + ret = ERR_PTR(-ENOMEM); + name = kmalloc(AFS_MAXCELLNAME + 1, GFP_KERNEL); + if (!name) + goto out_p; + + rcu_read_lock(); + do { + read_seqbegin_or_lock(&net->cells_lock, &seq); + cell = rcu_dereference_raw(net->ws_cell); + if (cell) { + len = cell->name_len; + memcpy(name, cell->name, len + 1); + } + } while (need_seqretry(&net->cells_lock, seq)); + done_seqretry(&net->cells_lock, seq); + rcu_read_unlock(); + + ret = ERR_PTR(-ENOENT); + if (!cell) + goto out_n; + + ret = lookup_one_len(name, dentry->d_parent, len); + + /* We don't want to d_add() the @cell dentry here as we don't want to + * the cached dentry to hide changes to the local cell name. + */ + +out_n: + kfree(name); +out_p: + return ret; +} + +/* + * Look up an entry in a dynroot directory. + */ +static struct dentry *afs_dynroot_lookup(struct inode *dir, struct dentry *dentry, + unsigned int flags) +{ + struct afs_vnode *vnode; + struct inode *inode; + int ret; + + vnode = AFS_FS_I(dir); + + _enter("%pd", dentry); + + ASSERTCMP(d_inode(dentry), ==, NULL); + + if (dentry->d_name.len >= AFSNAMEMAX) { + _leave(" = -ENAMETOOLONG"); + return ERR_PTR(-ENAMETOOLONG); + } + + if (dentry->d_name.len == 5 && + memcmp(dentry->d_name.name, "@cell", 5) == 0) + return afs_lookup_atcell(dentry); + + inode = afs_try_auto_mntpt(dentry, dir); + if (IS_ERR(inode)) { + ret = PTR_ERR(inode); + if (ret == -ENOENT) { + d_add(dentry, NULL); + _leave(" = NULL [negative]"); + return NULL; + } + _leave(" = %d [do]", ret); + return ERR_PTR(ret); + } + + d_add(dentry, inode); + _leave(" = 0 { ino=%lu v=%u }", + d_inode(dentry)->i_ino, d_inode(dentry)->i_generation); + return NULL; +} + +const struct inode_operations afs_dynroot_inode_operations = { + .lookup = afs_dynroot_lookup, +}; + +/* + * Dirs in the dynamic root don't need revalidation. + */ +static int afs_dynroot_d_revalidate(struct dentry *dentry, unsigned int flags) +{ + return 1; +} + +/* + * 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_dynroot_d_delete(const struct dentry *dentry) +{ + return d_really_is_positive(dentry); +} + +const struct dentry_operations afs_dynroot_dentry_operations = { + .d_revalidate = afs_dynroot_d_revalidate, + .d_delete = afs_dynroot_d_delete, + .d_release = afs_d_release, + .d_automount = afs_d_automount, +}; diff --git a/fs/afs/internal.h b/fs/afs/internal.h index adf9b17d328c..b6ec46ae03c3 100644 --- a/fs/afs/internal.h +++ b/fs/afs/internal.h @@ -671,11 +671,19 @@ extern bool afs_cm_incoming_call(struct afs_call *); */ extern const struct file_operations afs_dir_file_operations; extern const struct inode_operations afs_dir_inode_operations; -extern const struct file_operations afs_dynroot_file_operations; -extern const struct inode_operations afs_dynroot_inode_operations; extern const struct dentry_operations afs_fs_dentry_operations; extern bool afs_dir_check_page(struct inode *, struct page *); +extern void afs_d_release(struct dentry *); + +/* + * dynroot.c + */ +extern const struct file_operations afs_dynroot_file_operations; +extern const struct inode_operations afs_dynroot_inode_operations; +extern const struct dentry_operations afs_dynroot_dentry_operations; + +extern struct inode *afs_try_auto_mntpt(struct dentry *, struct inode *); /* * file.c diff --git a/fs/afs/super.c b/fs/afs/super.c index 3623c952b6ff..65081ec3c36e 100644 --- a/fs/afs/super.c +++ b/fs/afs/super.c @@ -154,7 +154,7 @@ static int afs_show_devname(struct seq_file *m, struct dentry *root) seq_puts(m, "none"); return 0; } - + switch (volume->type) { case AFSVL_RWVOL: break; @@ -269,7 +269,7 @@ static int afs_parse_device_name(struct afs_mount_params *params, int cellnamesz; _enter(",%s", name); - + if (!name) { printk(KERN_ERR "kAFS: no volume name specified\n"); return -EINVAL; @@ -418,7 +418,10 @@ static int afs_fill_super(struct super_block *sb, if (!sb->s_root) goto error; - sb->s_d_op = &afs_fs_dentry_operations; + if (params->dyn_root) + sb->s_d_op = &afs_dynroot_dentry_operations; + else + sb->s_d_op = &afs_fs_dentry_operations; _leave(" = 0"); return 0; @@ -676,7 +679,7 @@ static int afs_statfs(struct dentry *dentry, struct kstatfs *buf) buf->f_bfree = 0; return 0; } - + key = afs_request_key(vnode->volume->cell); if (IS_ERR(key)) return PTR_ERR(key);