From: Junjiro Okajima <hooanon05@xxxxxxxxxxx> initial commit file private data and address_space operations Signed-off-by: Junjiro Okajima <hooanon05@xxxxxxxxxxx> --- fs/aufs/file.c | 747 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ fs/aufs/file.h | 223 +++++++++++++++++ fs/aufs/finfo.c | 182 ++++++++++++++ 3 files changed, 1152 insertions(+), 0 deletions(-) create mode 100644 fs/aufs/file.c create mode 100644 fs/aufs/file.h create mode 100644 fs/aufs/finfo.c diff --git a/fs/aufs/file.c b/fs/aufs/file.c new file mode 100644 index 0000000..13bc36d --- /dev/null +++ b/fs/aufs/file.c @@ -0,0 +1,747 @@ +/* + * Copyright (C) 2005-2008 Junjiro Okajima + * + * This program, aufs 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. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + */ + +/* + * handling file/dir, and address_space operation + */ + +#include <linux/pagemap.h> +#include "aufs.h" + +/* + * a dirty trick for handling FMODE_EXEC and deny_write_access(). + * because FMODE_EXEC flag is not passed to f_op->open(), + * set it to file->private_data temporary. + */ +int au_store_fmode_exec(struct nameidata *nd, struct inode *inode) +{ + int err; + union { + void *p; + unsigned long ul; + } u; + + err = 0; + if (nd + && (nd->flags & LOOKUP_OPEN) + && nd->intent.open.file + && (nd->intent.open.flags & FMODE_EXEC) + && inode + && S_ISREG(inode->i_mode)) { + u.ul = nd->intent.open.flags; + nd->intent.open.file->private_data = u.p; + /* smp_mb(); */ + err = 1; + } + + return err; +} + +/* drop flags for writing */ +unsigned int au_file_roflags(unsigned int flags) +{ + flags &= ~(O_WRONLY | O_RDWR | O_APPEND | O_CREAT | O_TRUNC); + flags |= O_RDONLY | O_NOATIME; + return flags; +} + +/* common functions to regular file and dir */ +struct file *au_h_open(struct dentry *dentry, aufs_bindex_t bindex, int flags, + struct file *file) +{ + struct file *h_file; + struct dentry *h_dentry; + struct inode *h_inode; + struct super_block *sb; + struct au_branch *br; + int hinotify, err; + + LKTRTrace("%.*s, b%d, flags 0%o, f %d\n", + AuDLNPair(dentry), bindex, flags, !!file); + AuDebugOn(!dentry); + h_dentry = au_h_dptr(dentry, bindex); + AuDebugOn(!h_dentry); + h_inode = h_dentry->d_inode; + AuDebugOn(!h_inode); + + sb = dentry->d_sb; + hinotify = !!au_opt_test(au_mntflags(sb), UDBA_INOTIFY); + br = au_sbr(sb, bindex); + au_br_get(br); + /* drop flags for writing */ + if (au_test_ro(sb, bindex, dentry->d_inode)) + flags = au_file_roflags(flags); + flags &= ~O_CREAT; + + h_file = NULL; + if (unlikely(file && au_test_nfs(h_dentry->d_sb))) + h_file = au_h_intent(dentry, bindex, file); + if (!h_file) + h_file = dentry_open(dget(h_dentry), mntget(br->br_mnt), flags); + + /* + * a dirty trick for handling FMODE_EXEC and deny_write_access(). + */ + if (file && (file->f_mode & FMODE_EXEC)) { + h_file->f_mode |= FMODE_EXEC; + smp_mb(); /* flush f_mode */ + err = au_deny_write_access(h_file); + if (unlikely(err)) { + fput(h_file); + h_file = ERR_PTR(err); + } + } + if (!IS_ERR(h_file)) + return h_file; + + au_br_put(br); + AuTraceErrPtr(h_file); + return h_file; +} + +static int do_coo(struct dentry *dentry, aufs_bindex_t bstart) +{ + int err; + struct dentry *parent, *h_parent, *h_dentry, *gparent; + aufs_bindex_t bcpup; + struct inode *h_dir, *h_inode, *dir; + struct super_block *sb; + + LKTRTrace("%.*s\n", AuDLNPair(dentry)); + AuDebugOn(IS_ROOT(dentry)); + DiMustWriteLock(dentry); + + parent = dget_parent(dentry); + di_write_lock_parent(parent); + sb = dentry->d_sb; + err = AuWbrCopyup(au_sbi(sb), dentry); + bcpup = err; + if (err < 0) { + err = 0; /* stop copyup, it is not an error */ + goto out; + } + err = 0; + + h_parent = au_h_dptr(parent, bcpup); + if (!h_parent) { + err = au_cpup_dirs(dentry, bcpup, NULL); + if (unlikely(err)) + goto out; + h_parent = au_h_dptr(parent, bcpup); + } + + h_dir = h_parent->d_inode; + h_dentry = au_h_dptr(dentry, bstart); + h_inode = h_dentry->d_inode; + dir = parent->d_inode; + /* todo: meaningless lock if CONFIG_AUFS_DEBUG is disabled. */ + gparent = NULL; + if (unlikely(au_opt_test(au_mntflags(sb), UDBA_INOTIFY) + && !IS_ROOT(parent))) { + gparent = dget_parent(parent); + ii_read_lock_parent2(gparent->d_inode); + } + au_hdir_lock(h_dir, dir, bcpup); + /* todo: test parent-gparent relationship? */ + mutex_lock_nested(&h_inode->i_mutex, AuLsc_I_CHILD); + AuDebugOn(au_h_dptr(dentry, bcpup)); + err = au_sio_cpup_simple(dentry, bcpup, -1, AuCpup_DTIME); + AuTraceErr(err); + mutex_unlock(&h_inode->i_mutex); + au_hdir_unlock(h_dir, dir, bcpup); + if (unlikely(gparent)) { + ii_read_unlock(gparent->d_inode); + dput(gparent); + } + + out: + di_write_unlock(parent); + dput(parent); + AuTraceErr(err); + return err; +} + +int au_do_open(struct inode *inode, struct file *file, + int (*open)(struct file *file, int flags)) +{ + int err, coo; + struct dentry *dentry; + struct super_block *sb; + aufs_bindex_t bstart; + + dentry = file->f_dentry; + LKTRTrace("i%lu, %.*s\n", inode->i_ino, AuDLNPair(dentry)); + + sb = dentry->d_sb; + si_read_lock(sb, AuLock_FLUSH); + coo = 0; + switch (au_mntflags(sb) & AuOptMask_COO) { + case AuOpt_COO_LEAF: + coo = !S_ISDIR(inode->i_mode); + break; + case AuOpt_COO_ALL: + coo = 1; + break; + } + err = au_finfo_init(file); + if (unlikely(err)) + goto out; + + if (!coo) { + di_read_lock_child(dentry, AuLock_IR); + bstart = au_dbstart(dentry); + } else { + di_write_lock_child(dentry); + bstart = au_dbstart(dentry); + if (au_test_ro(sb, bstart, dentry->d_inode)) { + err = do_coo(dentry, bstart); + if (err) { + di_write_unlock(dentry); + goto out_finfo; + } + bstart = au_dbstart(dentry); + } + di_downgrade_lock(dentry, AuLock_IR); + } + + err = open(file, file->f_flags); + di_read_unlock(dentry, AuLock_IR); + + out_finfo: + fi_write_unlock(file); + if (unlikely(err)) + au_finfo_fin(file); + out: + si_read_unlock(sb); + AuTraceErr(err); + return err; +} + +int au_reopen_nondir(struct file *file) +{ + int err; + struct dentry *dentry; + aufs_bindex_t bstart, bindex, bend; + struct file *h_file, *h_file_tmp; + + dentry = file->f_dentry; + LKTRTrace("%.*s\n", AuDLNPair(dentry)); + bstart = au_dbstart(dentry); + AuDebugOn(S_ISDIR(dentry->d_inode->i_mode) + || !au_h_dptr(dentry, bstart)->d_inode); + + h_file_tmp = NULL; + if (au_fbstart(file) == bstart) { + h_file = au_h_fptr(file, bstart); + if (file->f_mode == h_file->f_mode) + return 0; /* success */ + h_file_tmp = h_file; + get_file(h_file_tmp); + au_set_h_fptr(file, bstart, NULL); + } + AuDebugOn(au_fbstart(file) < bstart + || au_fi(file)->fi_hfile[0 + bstart].hf_file); + + h_file = au_h_open(dentry, bstart, file->f_flags & ~O_TRUNC, file); + err = PTR_ERR(h_file); + if (IS_ERR(h_file)) + goto out; /* todo: close all? */ + err = 0; + /* cpup_file_flags(h_file, file); */ + au_set_fbstart(file, bstart); + au_set_h_fptr(file, bstart, h_file); + au_update_figen(file); + /* todo: necessary? */ + /* file->f_ra = h_file->f_ra; */ + + /* close lower files */ + bend = au_fbend(file); + for (bindex = bstart + 1; bindex <= bend; bindex++) + au_set_h_fptr(file, bindex, NULL); + au_set_fbend(file, bstart); + + out: + if (h_file_tmp) + fput(h_file_tmp); + AuTraceErr(err); + return err; +} + +/* ---------------------------------------------------------------------- */ + +static int au_ready_to_write_wh(struct file *file, loff_t len, + aufs_bindex_t bcpup) +{ + int err; + struct dentry *dentry, *hi_wh, *old_h_dentry; + struct au_dinfo *dinfo; + aufs_bindex_t old_bstart; + + AuTraceEnter(); + + dentry = file->f_dentry; + hi_wh = au_hi_wh(dentry->d_inode, bcpup); + if (!hi_wh) + err = au_sio_cpup_wh(dentry, bcpup, len, file); + else { + /* already copied-up after unlink */ + dinfo = au_di(dentry); + old_bstart = dinfo->di_bstart; + dinfo->di_bstart = bcpup; + old_h_dentry = dinfo->di_hdentry[0 + bcpup].hd_dentry; + dinfo->di_hdentry[0 + bcpup].hd_dentry = hi_wh; + err = au_reopen_nondir(file); + dinfo->di_hdentry[0 + bcpup].hd_dentry = old_h_dentry; + dinfo->di_bstart = old_bstart; + } + + AuTraceErr(err); + return err; +} + +/* + * prepare the @file for writing. + */ +int au_ready_to_write(struct file *file, loff_t len) +{ + int err; + struct dentry *dentry, *parent, *h_dentry, *h_parent, *gparent; + struct inode *h_inode, *h_dir, *inode, *dir; + struct super_block *sb; + aufs_bindex_t bstart, bcpup; + + dentry = file->f_dentry; + LKTRTrace("%.*s, len %Ld\n", AuDLNPair(dentry), len); + FiMustWriteLock(file); + + sb = dentry->d_sb; + bstart = au_fbstart(file); + AuDebugOn(au_fbr(file, bstart) != au_sbr(sb, bstart)); + + inode = dentry->d_inode; + AuDebugOn(S_ISDIR(inode->i_mode)); + ii_read_lock_child(inode); + LKTRTrace("rdonly %d, bstart %d\n", + au_test_ro(sb, bstart, inode), bstart); + err = au_test_ro(sb, bstart, inode); + ii_read_unlock(inode); + if (!err && (au_h_fptr(file, bstart)->f_mode & FMODE_WRITE)) + return 0; + + /* need to cpup */ + di_write_lock_child(dentry); + parent = dget_parent(dentry); + di_write_lock_parent(parent); + err = AuWbrCopyup(au_sbi(sb), dentry); + bcpup = err; + if (unlikely(err < 0)) + goto out_unlock; + err = 0; + + h_parent = au_h_dptr(parent, bcpup); + if (!h_parent) { + err = au_cpup_dirs(dentry, bcpup, NULL); + if (unlikely(err)) + goto out_unlock; + h_parent = au_h_dptr(parent, bcpup); + } + + /* todo: meaningless lock if CONFIG_AUFS_DEBUG is disabled. */ + gparent = NULL; + if (unlikely(au_opt_test(au_mntflags(sb), UDBA_INOTIFY) + && !IS_ROOT(parent))) { + gparent = dget_parent(parent); + ii_read_lock_parent2(gparent->d_inode); + } + h_dir = h_parent->d_inode; + h_dentry = au_h_fptr(file, au_fbstart(file))->f_dentry; + h_inode = h_dentry->d_inode; + dir = parent->d_inode; + au_hdir_lock(h_dir, dir, bcpup); + /* todo: test parent-gparent relationship? */ + mutex_lock_nested(&h_inode->i_mutex, AuLsc_I_CHILD); + if (d_unhashed(dentry) /* || d_unhashed(h_dentry) */ + /* || !h_inode->i_nlink */) + err = au_ready_to_write_wh(file, len, bcpup); + else { + if (!au_h_dptr(dentry, bcpup)) + err = au_sio_cpup_simple(dentry, bcpup, len, + AuCpup_DTIME); + AuTraceErr(err); + if (!err) + err = au_reopen_nondir(file); + AuTraceErr(err); + } + mutex_unlock(&h_inode->i_mutex); + au_hdir_unlock(h_dir, dir, bcpup); + if (unlikely(gparent)) { + ii_read_unlock(gparent->d_inode); + dput(gparent); + } + + out_unlock: + di_write_unlock(parent); + di_write_unlock(dentry); + dput(parent); + AuTraceErr(err); + return err; + +} + +/* ---------------------------------------------------------------------- */ + +static int refresh_file_by_inode(struct file *file, int *need_reopen) +{ + int err; + struct au_finfo *finfo; + struct dentry *dentry, *parent, *old_h_dentry, *hi_wh; + struct inode *inode, *dir, *h_dir; + aufs_bindex_t bstart, new_bstart, old_bstart; + struct super_block *sb; + struct au_dinfo *dinfo; + + dentry = file->f_dentry; + LKTRTrace("%.*s\n", AuDLNPair(dentry)); + FiMustWriteLock(file); + + err = 0; + finfo = au_fi(file); + inode = dentry->d_inode; + sb = dentry->d_sb; + again: + bstart = au_ibstart(inode); + if (bstart == finfo->fi_bstart) + goto out; + + new_bstart = bstart; + parent = dget_parent(dentry); + dir = parent->d_inode; + if (au_test_ro(sb, bstart, inode)) { + di_read_lock_parent(parent, !AuLock_IR); + err = AuWbrCopyup(au_sbi(sb), dentry); + new_bstart = err; + di_read_unlock(parent, !AuLock_IR); + if (unlikely(err < 0)) + goto out_put; + } + di_read_unlock(dentry, AuLock_IR); + di_write_lock_child(dentry); + /* someone else might change our inode while we were sleeping */ + /* todo: test more? */ + if (bstart != au_ibstart(inode)) { + di_downgrade_lock(dentry, AuLock_IR); + err = 0; + dput(parent); + goto again; + } + di_read_lock_parent(parent, AuLock_IR); + bstart = new_bstart; + + hi_wh = au_hi_wh(inode, bstart); + if (au_opt_test(au_mntflags(sb), PLINK) + && au_plink_test(sb, inode) + && !d_unhashed(dentry)) { + err = au_test_and_cpup_dirs(dentry, bstart, NULL); + + /* always superio. */ +#if 1 /* reserved for future use */ + h_dir = au_h_dptr(parent, bstart)->d_inode; + au_hdir_lock(h_dir, dir, bstart); + err = au_sio_cpup_simple(dentry, bstart, -1, AuCpup_DTIME); + au_hdir_unlock(h_dir, dir, bstart); +#else + if (!au_test_wkq(current)) { + int wkq_err; + struct cpup_pseudo_link_args args = { + .errp = &err, + .dentry = dentry, + .bdst = bstart, + .do_lock = 1 + }; + wkq_err = au_wkq_wait(call_cpup_pseudo_link, &args); + if (unlikely(wkq_err)) + err = wkq_err; + } else + err = cpup_pseudo_link(dentry, bstart, /*do_lock*/1); +#endif + } else if (hi_wh) { + /* already copied-up after unlink */ + dinfo = au_di(dentry); + old_bstart = dinfo->di_bstart; + dinfo->di_bstart = bstart; + old_h_dentry = dinfo->di_hdentry[0 + bstart].hd_dentry; + dinfo->di_hdentry[0 + bstart].hd_dentry = hi_wh; + err = au_reopen_nondir(file); + dinfo->di_hdentry[0 + bstart].hd_dentry = old_h_dentry; + dinfo->di_bstart = old_bstart; + *need_reopen = 0; + } + di_read_unlock(parent, AuLock_IR); + di_downgrade_lock(dentry, AuLock_IR); + + out_put: + dput(parent); + out: + AuTraceErr(err); + return err; +} + +/* + * after branch manipulating, refresh the file. + */ +static int refresh_file(struct file *file, int (*reopen)(struct file *file)) +{ + int err, new_sz, need_reopen; + struct dentry *dentry; + aufs_bindex_t bend, bindex, bstart, brid; + struct au_hfile *p; + struct au_finfo *finfo; + struct super_block *sb; + struct inode *inode; + struct file *hidden_file; + + dentry = file->f_dentry; + LKTRTrace("%.*s\n", AuDLNPair(dentry)); + FiMustWriteLock(file); + DiMustReadLock(dentry); + inode = dentry->d_inode; + IiMustReadLock(inode); + + err = -ENOMEM; + sb = dentry->d_sb; + finfo = au_fi(file); + bstart = finfo->fi_bstart; + bend = finfo->fi_bstart; + new_sz = sizeof(*finfo->fi_hfile) * (au_sbend(sb) + 1); + p = au_kzrealloc(finfo->fi_hfile, sizeof(*p) * (finfo->fi_bend + 1), + new_sz, GFP_KERNEL); + if (unlikely(!p)) + goto out; + finfo->fi_hfile = p; + hidden_file = p[0 + bstart].hf_file; + + p = finfo->fi_hfile + finfo->fi_bstart; + brid = p->hf_br->br_id; + bend = finfo->fi_bend; + for (bindex = finfo->fi_bstart; bindex <= bend; bindex++, p++) { + struct au_hfile tmp, *q; + aufs_bindex_t new_bindex; + + if (!p->hf_file) + continue; + new_bindex = au_find_bindex(sb, p->hf_br); + if (new_bindex == bindex) + continue; + /* todo: test more? */ + if (new_bindex < 0) { + au_set_h_fptr(file, bindex, NULL); + continue; + } + + /* swap two hidden inode, and loop again */ + q = finfo->fi_hfile + new_bindex; + tmp = *q; + *q = *p; + *p = tmp; + if (tmp.hf_file) { + bindex--; + p--; + } + } + { + aufs_bindex_t s = finfo->fi_bstart, e = finfo->fi_bend; + finfo->fi_bstart = 0; + finfo->fi_bend = au_sbend(sb); + finfo->fi_bstart = s; + finfo->fi_bend = e; + } + + p = finfo->fi_hfile; + if (!au_test_mmapped(file) && !d_unhashed(dentry)) { + bend = au_sbend(sb); + for (finfo->fi_bstart = 0; finfo->fi_bstart <= bend; + finfo->fi_bstart++, p++) + if (p->hf_file) { + if (p->hf_file->f_dentry + && p->hf_file->f_dentry->d_inode) + break; + else + au_hfput(p); + } + } else { + bend = au_br_index(sb, brid); + for (finfo->fi_bstart = 0; finfo->fi_bstart < bend; + finfo->fi_bstart++, p++) + if (p->hf_file) + au_hfput(p); + bend = au_sbend(sb); + } + + p = finfo->fi_hfile + bend; + for (finfo->fi_bend = bend; finfo->fi_bend >= finfo->fi_bstart; + finfo->fi_bend--, p--) + if (p->hf_file) { + if (p->hf_file->f_dentry + && p->hf_file->f_dentry->d_inode) + break; + else + au_hfput(p); + } + AuDebugOn(finfo->fi_bend < finfo->fi_bstart); + + err = 0; + need_reopen = 1; + if (!au_test_mmapped(file)) + err = refresh_file_by_inode(file, &need_reopen); + if (!err && need_reopen && !d_unhashed(dentry)) + err = reopen(file); + if (!err) { + au_update_figen(file); + return 0; /* success */ + } + + /* error, close all hidden files */ + bend = au_fbend(file); + for (bindex = au_fbstart(file); bindex <= bend; bindex++) + au_set_h_fptr(file, bindex, NULL); + + out: + AuTraceErr(err); + return err; +} + +/* common function to regular file and dir */ +int au_reval_and_lock_finfo(struct file *file, int (*reopen)(struct file *file), + int wlock, int locked) +{ + int err, pseudo_link; + struct dentry *dentry; + struct super_block *sb; + aufs_bindex_t bstart; + au_gen_t sgen, fgen; + + dentry = file->f_dentry; + LKTRTrace("%.*s, w %d, l %d\n", AuDLNPair(dentry), wlock, locked); + sb = dentry->d_sb; + SiMustAnyLock(sb); + + err = 0; + sgen = au_sigen(sb); + fi_write_lock(file); + fgen = au_figen(file); + di_read_lock_child(dentry, AuLock_IR); + bstart = au_dbstart(dentry); + pseudo_link = (bstart != au_ibstart(dentry->d_inode)); + di_read_unlock(dentry, AuLock_IR); + if (sgen == fgen && !pseudo_link && au_fbstart(file) == bstart) { + if (!wlock) + fi_downgrade_lock(file); + return 0; /* success */ + } + + LKTRTrace("sgen %d, fgen %d\n", sgen, fgen); + if (unlikely(sgen != au_digen(dentry) + || sgen != au_iigen(dentry->d_inode))) { + /* + * d_path() and path_lookup() is a simple and good approach + * to revalidate. but si_rwsem in DEBUG_RWSEM will cause a + * deadlock. removed the code. + */ + di_write_lock_child(dentry); + err = au_reval_dpath(dentry, sgen); + di_write_unlock(dentry); + if (unlikely(err < 0)) + goto out; + AuDebugOn(au_digen(dentry) != sgen + || au_iigen(dentry->d_inode) != sgen); + } + + di_read_lock_child(dentry, AuLock_IR); + err = refresh_file(file, reopen + /* , au_opt_test(au_mnt_flags(sb), REFROF) */); + di_read_unlock(dentry, AuLock_IR); + if (!err) { + if (!wlock) + fi_downgrade_lock(file); + } else + fi_write_unlock(file); + + out: + AuTraceErr(err); + return err; +} + +/* ---------------------------------------------------------------------- */ + +/* cf. aufs_nopage() */ +/* for madvise(2) */ +static int aufs_readpage(struct file *file, struct page *page) +{ + AuTraceEnter(); + unlock_page(page); + return 0; +} + +/* they will never be called. */ +#ifdef CONFIG_AUFS_DEBUG +static int aufs_prepare_write(struct file *file, struct page *page, + unsigned from, unsigned to) +{ AuUnsupport(); return 0; } +static int aufs_commit_write(struct file *file, struct page *page, + unsigned from, unsigned to) +{ AuUnsupport(); return 0; } +static int aufs_write_begin(struct file *file, struct address_space *mapping, + loff_t pos, unsigned len, unsigned flags, + struct page **pagep, void **fsdata) +{ AuUnsupport(); return 0; } +static int aufs_write_end(struct file *file, struct address_space *mapping, + loff_t pos, unsigned len, unsigned copied, + struct page *page, void *fsdata) +{ AuUnsupport(); return 0; } +static int aufs_writepage(struct page *page, struct writeback_control *wbc) +{ AuUnsupport(); return 0; } +static void aufs_sync_page(struct page *page) +{ AuUnsupport(); } + +static int aufs_set_page_dirty(struct page *page) +{ AuUnsupport(); return 0; } +static void aufs_invalidatepage(struct page *page, unsigned long offset) +{ AuUnsupport(); } +static int aufs_releasepage(struct page *page, gfp_t gfp) +{ AuUnsupport(); return 0; } +static ssize_t aufs_direct_IO(int rw, struct kiocb *iocb, + const struct iovec *iov, loff_t offset, + unsigned long nr_segs) +{ AuUnsupport(); return 0; } +#endif /* CONFIG_AUFS_DEBUG */ + +struct address_space_operations aufs_aop = { + .readpage = aufs_readpage, +#ifdef CONFIG_AUFS_DEBUG + .writepage = aufs_writepage, + .sync_page = aufs_sync_page, + .set_page_dirty = aufs_set_page_dirty, + .prepare_write = aufs_prepare_write, + .commit_write = aufs_commit_write, + .write_begin = aufs_write_begin, + .write_end = aufs_write_end, + .invalidatepage = aufs_invalidatepage, + .releasepage = aufs_releasepage, + .direct_IO = aufs_direct_IO, +#endif /* CONFIG_AUFS_DEBUG */ +}; diff --git a/fs/aufs/file.h b/fs/aufs/file.h new file mode 100644 index 0000000..150e53c --- /dev/null +++ b/fs/aufs/file.h @@ -0,0 +1,223 @@ +/* + * Copyright (C) 2005-2008 Junjiro Okajima + * + * This program, aufs 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. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + */ + +/* + * file operations + */ + +#ifndef __AUFS_FILE_H__ +#define __AUFS_FILE_H__ + +#ifdef __KERNEL__ + +#include <linux/file.h> +#include <linux/fs.h> +#include <linux/mm.h> +#include <linux/aufs_type.h> +#include "dentry.h" +#include "misc.h" +#include "super.h" + +/* ---------------------------------------------------------------------- */ + +struct au_branch; +struct au_hfile { + struct file *hf_file; + struct au_branch *hf_br; +}; + +struct au_vdir; +struct au_finfo { + atomic_t fi_generation; + + struct au_rwsem fi_rwsem; + struct au_hfile *fi_hfile; + aufs_bindex_t fi_bstart, fi_bend; + + union { + struct vm_operations_struct *fi_h_vm_ops; + struct au_vdir *fi_vdir_cache; + }; +}; + +/* ---------------------------------------------------------------------- */ + +/* file.c */ +extern struct address_space_operations aufs_aop; +unsigned int au_file_roflags(unsigned int flags); +struct file *au_h_open(struct dentry *dentry, aufs_bindex_t bindex, int flags, + struct file *file); +int au_do_open(struct inode *inode, struct file *file, + int (*open)(struct file *file, int flags)); +int au_reopen_nondir(struct file *file); +int au_ready_to_write(struct file *file, loff_t len); +int au_reval_and_lock_finfo(struct file *file, int (*reopen)(struct file *file), + int wlock, int locked); + +/* f_op.c */ +extern struct file_operations aufs_file_fop; +int aufs_flush(struct file *file, fl_owner_t id); + +/* finfo.c */ +struct au_finfo *au_fi(struct file *file); +struct au_branch *au_fbr(struct file *file, aufs_bindex_t bindex); +struct file *au_h_fptr(struct file *file, aufs_bindex_t bindex); + +void au_hfput(struct au_hfile *hf); +void au_set_h_fptr(struct file *file, aufs_bindex_t bindex, + struct file *h_file); + +void au_finfo_fin(struct file *file); +int au_finfo_init(struct file *file); + +#ifdef CONFIG_AUFS_ROBR +/* robr.c */ +struct file *au_robr_safe_file(struct vm_area_struct *vma); +void au_robr_reset_file(struct vm_area_struct *vma, struct file *file); +#else +static inline struct file *au_robr_safe_file(struct vm_area_struct *vma) +{ + struct file *file; + + file = vma->vm_file; + if (file->private_data && au_test_aufs(file->f_dentry->d_sb)) + return file; + return NULL; +} + +static inline +void au_robr_reset_file(struct vm_area_struct *vma, struct file *file) +{ + vma->vm_file = file; + /* smp_mb(); */ /* flush vm_file */ +} +#endif /* CONFIG_AUFS_ROBR */ + +/* ---------------------------------------------------------------------- */ + +/* todo: memory barrier? */ +static inline au_gen_t au_figen(struct file *f) +{ + return atomic_read(&au_fi(f)->fi_generation); +} + +static inline int au_test_mmapped(struct file *f) +{ + return !!(au_fi(f)->fi_h_vm_ops); +} + +static inline int au_test_aufs_file(struct file *f) +{ + return !(f->f_dentry->d_inode->i_mode + & (S_IFCHR | S_IFBLK | S_IFIFO | S_IFSOCK)); +} + +/* ---------------------------------------------------------------------- */ + +int au_store_fmode_exec(struct nameidata *nd, struct inode *inode); + +static inline int au_deny_write_access(struct file *h_file) +{ + LKTRTrace("%.*s\n", AuDLNPair(h_file->f_dentry)); + return deny_write_access(h_file); +} + +static inline void au_allow_write_access(struct file *h_file) +{ + allow_write_access(h_file); +} + +/* ---------------------------------------------------------------------- */ + +/* + * fi_read_lock, fi_write_lock, + * fi_read_unlock, fi_write_unlock, fi_downgrade_lock + */ +AuSimpleRwsemFuncs(fi, struct file *f, au_fi(f)->fi_rwsem); + +/* to debug easier, do not make them inlined functions */ +#define FiMustReadLock(f) do { \ + SiMustAnyLock((f)->f_dentry->d_sb); \ + AuRwMustReadLock(&au_fi(f)->fi_rwsem); \ +} while (0) + +#define FiMustWriteLock(f) do { \ + SiMustAnyLock((f)->f_dentry->d_sb); \ + AuRwMustWriteLock(&au_fi(f)->fi_rwsem); \ +} while (0) + +#define FiMustAnyLock(f) do { \ + SiMustAnyLock((f)->f_dentry->d_sb); \ + AuRwMustAnyLock(&au_fi(f)->fi_rwsem); \ +} while (0) + +#define FiMustNoWaiters(f) AuRwMustNoWaiters(&au_fi(f)->fi_rwsem) + +/* ---------------------------------------------------------------------- */ + +/* todo: hard/soft set? */ +static inline aufs_bindex_t au_fbstart(struct file *file) +{ + FiMustAnyLock(file); + return au_fi(file)->fi_bstart; +} + +static inline aufs_bindex_t au_fbend(struct file *file) +{ + FiMustAnyLock(file); + return au_fi(file)->fi_bend; +} + +static inline struct au_vdir *au_fvdir_cache(struct file *file) +{ + FiMustAnyLock(file); + return au_fi(file)->fi_vdir_cache; +} + +static inline void au_set_fbstart(struct file *file, aufs_bindex_t bindex) +{ + FiMustWriteLock(file); + AuDebugOn(au_sbend(file->f_dentry->d_sb) < bindex); + au_fi(file)->fi_bstart = bindex; +} + +static inline void au_set_fbend(struct file *file, aufs_bindex_t bindex) +{ + FiMustWriteLock(file); + AuDebugOn(au_sbend(file->f_dentry->d_sb) < bindex + || bindex < au_fbstart(file)); + au_fi(file)->fi_bend = bindex; +} + +static inline void au_set_fvdir_cache(struct file *file, + struct au_vdir *vdir_cache) +{ + FiMustWriteLock(file); + AuDebugOn(!S_ISDIR(file->f_dentry->d_inode->i_mode) + || (au_fi(file)->fi_vdir_cache && vdir_cache)); + au_fi(file)->fi_vdir_cache = vdir_cache; +} + +static inline void au_update_figen(struct file *file) +{ + atomic_set(&au_fi(file)->fi_generation, au_digen(file->f_dentry)); + /* smp_mb(); */ /* atomic_set */ +} + +#endif /* __KERNEL__ */ +#endif /* __AUFS_FILE_H__ */ diff --git a/fs/aufs/finfo.c b/fs/aufs/finfo.c new file mode 100644 index 0000000..8588fd1 --- /dev/null +++ b/fs/aufs/finfo.c @@ -0,0 +1,182 @@ +/* + * Copyright (C) 2005-2008 Junjiro Okajima + * + * This program, aufs 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. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + */ + +/* + * file private data + */ + +#include "aufs.h" + +struct au_finfo *au_fi(struct file *file) +{ + struct au_finfo *finfo = file->private_data; + AuDebugOn(!finfo + || !finfo->fi_hfile + || (0 < finfo->fi_bend + && (/* au_sbi(file->f_dentry->d_sb)->si_bend + < finfo->fi_bend + || */ finfo->fi_bend < finfo->fi_bstart))); + return finfo; +} + +struct au_branch *au_fbr(struct file *file, aufs_bindex_t bindex) +{ + struct au_finfo *finfo = au_fi(file); + struct au_hfile *hf; + + FiMustAnyLock(file); + AuDebugOn(!finfo + || finfo->fi_bstart < 0 + || bindex < finfo->fi_bstart + || finfo->fi_bend < bindex); + hf = finfo->fi_hfile + bindex; + AuDebugOn(hf->hf_br && au_br_count(hf->hf_br) <= 0); + return hf->hf_br; +} + +struct file *au_h_fptr(struct file *file, aufs_bindex_t bindex) +{ + struct au_finfo *finfo = au_fi(file); + struct au_hfile *hf; + + FiMustAnyLock(file); + AuDebugOn(!finfo + || finfo->fi_bstart < 0 + || bindex < finfo->fi_bstart + || finfo->fi_bend < bindex); + hf = finfo->fi_hfile + bindex; + AuDebugOn(hf->hf_file + && file_count(hf->hf_file) <= 0 + && au_br_count(hf->hf_br) <= 0); + return hf->hf_file; +} + +void au_hfput(struct au_hfile *hf) +{ + if (hf->hf_file->f_mode & FMODE_EXEC) + au_allow_write_access(hf->hf_file); + fput(hf->hf_file); + hf->hf_file = NULL; + AuDebugOn(!hf->hf_br); + au_br_put(hf->hf_br); + hf->hf_br = NULL; +} + +void au_set_h_fptr(struct file *file, aufs_bindex_t bindex, struct file *val) +{ + struct au_finfo *finfo = au_fi(file); + struct au_hfile *hf; + + FiMustWriteLock(file); + AuDebugOn(!finfo + || finfo->fi_bstart < 0 + || bindex < finfo->fi_bstart + || finfo->fi_bend < bindex); + AuDebugOn(val && file_count(val) <= 0); + hf = finfo->fi_hfile + bindex; + AuDebugOn(val && hf->hf_file); + if (hf->hf_file) + au_hfput(hf); + if (val) { + hf->hf_file = val; + hf->hf_br = au_sbr(file->f_dentry->d_sb, bindex); + } +} + +void au_finfo_fin(struct file *file) +{ + struct au_finfo *finfo; + struct dentry *dentry; + aufs_bindex_t bindex, bend; + + dentry = file->f_dentry; + LKTRTrace("%.*s\n", AuDLNPair(dentry)); + SiMustAnyLock(dentry->d_sb); + + fi_write_lock(file); + bend = au_fbend(file); + bindex = au_fbstart(file); + if (bindex >= 0) + for (; bindex <= bend; bindex++) + au_set_h_fptr(file, bindex, NULL); + + finfo = au_fi(file); +#ifdef CONFIG_AUFS_DEBUG + if (finfo->fi_bstart >= 0) { + bend = au_fbend(file); + for (bindex = finfo->fi_bstart; bindex <= bend; bindex++) { + struct au_hfile *hf; + hf = finfo->fi_hfile + bindex; + AuDebugOn(hf->hf_file || hf->hf_br); + } + } +#endif + + kfree(finfo->fi_hfile); + fi_write_unlock(file); + au_cache_free_finfo(finfo); +} + +int au_finfo_init(struct file *file) +{ + struct au_finfo *finfo; + struct dentry *dentry; + union { + void *p; + unsigned long ul; + } u; + + dentry = file->f_dentry; + LKTRTrace("%.*s\n", AuDLNPair(dentry)); + AuDebugOn(!dentry->d_inode); + + finfo = au_cache_alloc_finfo(); + if (finfo) { + finfo->fi_hfile = kcalloc(au_sbend(dentry->d_sb) + 1, + sizeof(*finfo->fi_hfile), GFP_KERNEL); + if (finfo->fi_hfile) { + au_rw_init_wlock(&finfo->fi_rwsem); + finfo->fi_bstart = -1; + finfo->fi_bend = -1; + atomic_set(&finfo->fi_generation, au_digen(dentry)); + /* smp_mb(); */ /* atomic_set */ + + /* + * a dirty trick for handling FMODE_EXEC and + * deny_write_access(). + * because FMODE_EXEC flag is not passed to + * f_op->open(), + * aufs set it to file->private_data temporary in lookup + * or dentry revalidation operations. + * restore the flag to f_mode here. + */ + u.p = file->private_data; + if (u.ul & FMODE_EXEC) { + file->f_mode |= FMODE_EXEC; + smp_mb(); /* flush f_mode */ + } + + file->private_data = finfo; + return 0; /* success */ + } + au_cache_free_finfo(finfo); + } + + AuTraceErr(-ENOMEM); + return -ENOMEM; +} -- 1.5.5.1.308.g1fbb5.dirty -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html