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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2016-03-25 03:53:42 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2016-03-25 03:53:42 -0300
commit03dd4cb26d967f9588437b0fc9cc0e8353322bb7 (patch)
treefa581f6dc1c0596391690d1f67eceef3af8246dc /fs/aufs/f_op.c
parentd4e493caf788ef44982e131ff9c786546904d934 (diff)
Linux-libre 4.5-gnu
Diffstat (limited to 'fs/aufs/f_op.c')
-rw-r--r--fs/aufs/f_op.c759
1 files changed, 0 insertions, 759 deletions
diff --git a/fs/aufs/f_op.c b/fs/aufs/f_op.c
deleted file mode 100644
index 145dec870..000000000
--- a/fs/aufs/f_op.c
+++ /dev/null
@@ -1,759 +0,0 @@
-/*
- * Copyright (C) 2005-2016 Junjiro R. Okajima
- */
-
-/*
- * file and vm operations
- */
-
-#include <linux/aio.h>
-#include <linux/fs_stack.h>
-#include <linux/mman.h>
-#include <linux/security.h>
-#include "aufs.h"
-
-int au_do_open_nondir(struct file *file, int flags, struct file *h_file)
-{
- int err;
- aufs_bindex_t bindex;
- struct dentry *dentry, *h_dentry;
- struct au_finfo *finfo;
- struct inode *h_inode;
-
- FiMustWriteLock(file);
-
- err = 0;
- dentry = file->f_path.dentry;
- AuDebugOn(IS_ERR_OR_NULL(dentry));
- finfo = au_fi(file);
- memset(&finfo->fi_htop, 0, sizeof(finfo->fi_htop));
- atomic_set(&finfo->fi_mmapped, 0);
- bindex = au_dbstart(dentry);
- if (!h_file) {
- h_dentry = au_h_dptr(dentry, bindex);
- err = vfsub_test_mntns(file->f_path.mnt, h_dentry->d_sb);
- if (unlikely(err))
- goto out;
- h_file = au_h_open(dentry, bindex, flags, file, /*force_wr*/0);
- } else {
- h_dentry = h_file->f_path.dentry;
- err = vfsub_test_mntns(file->f_path.mnt, h_dentry->d_sb);
- if (unlikely(err))
- goto out;
- get_file(h_file);
- }
- if (IS_ERR(h_file))
- err = PTR_ERR(h_file);
- else {
- if ((flags & __O_TMPFILE)
- && !(flags & O_EXCL)) {
- h_inode = file_inode(h_file);
- spin_lock(&h_inode->i_lock);
- h_inode->i_state |= I_LINKABLE;
- spin_unlock(&h_inode->i_lock);
- }
- au_set_fbstart(file, bindex);
- au_set_h_fptr(file, bindex, h_file);
- au_update_figen(file);
- /* todo: necessary? */
- /* file->f_ra = h_file->f_ra; */
- }
-
-out:
- return err;
-}
-
-static int aufs_open_nondir(struct inode *inode __maybe_unused,
- struct file *file)
-{
- int err;
- struct super_block *sb;
- struct au_do_open_args args = {
- .open = au_do_open_nondir
- };
-
- AuDbg("%pD, f_flags 0x%x, f_mode 0x%x\n",
- file, vfsub_file_flags(file), file->f_mode);
-
- sb = file->f_path.dentry->d_sb;
- si_read_lock(sb, AuLock_FLUSH);
- err = au_do_open(file, &args);
- si_read_unlock(sb);
- return err;
-}
-
-int aufs_release_nondir(struct inode *inode __maybe_unused, struct file *file)
-{
- struct au_finfo *finfo;
- aufs_bindex_t bindex;
-
- finfo = au_fi(file);
- au_sphl_del(&finfo->fi_hlist,
- &au_sbi(file->f_path.dentry->d_sb)->si_files);
- bindex = finfo->fi_btop;
- if (bindex >= 0)
- au_set_h_fptr(file, bindex, NULL);
-
- au_finfo_fin(file);
- return 0;
-}
-
-/* ---------------------------------------------------------------------- */
-
-static int au_do_flush_nondir(struct file *file, fl_owner_t id)
-{
- int err;
- struct file *h_file;
-
- err = 0;
- h_file = au_hf_top(file);
- if (h_file)
- err = vfsub_flush(h_file, id);
- return err;
-}
-
-static int aufs_flush_nondir(struct file *file, fl_owner_t id)
-{
- return au_do_flush(file, id, au_do_flush_nondir);
-}
-
-/* ---------------------------------------------------------------------- */
-/*
- * read and write functions acquire [fdi]_rwsem once, but release before
- * mmap_sem. This is because to stop a race condition between mmap(2).
- * Releasing these aufs-rwsem should be safe, no branch-mamagement (by keeping
- * si_rwsem), no harmful copy-up should happen. Actually copy-up may happen in
- * read functions after [fdi]_rwsem are released, but it should be harmless.
- */
-
-/* Callers should call au_read_post() or fput() in the end */
-struct file *au_read_pre(struct file *file, int keep_fi)
-{
- struct file *h_file;
- int err;
-
- err = au_reval_and_lock_fdi(file, au_reopen_nondir, /*wlock*/0);
- if (!err) {
- di_read_unlock(file->f_path.dentry, AuLock_IR);
- h_file = au_hf_top(file);
- get_file(h_file);
- if (!keep_fi)
- fi_read_unlock(file);
- } else
- h_file = ERR_PTR(err);
-
- return h_file;
-}
-
-static void au_read_post(struct inode *inode, struct file *h_file)
-{
- /* update without lock, I don't think it a problem */
- fsstack_copy_attr_atime(inode, file_inode(h_file));
- fput(h_file);
-}
-
-struct au_write_pre {
- blkcnt_t blks;
- aufs_bindex_t bstart;
-};
-
-/*
- * return with iinfo is write-locked
- * callers should call au_write_post() or iinfo_write_unlock() + fput() in the
- * end
- */
-static struct file *au_write_pre(struct file *file, int do_ready,
- struct au_write_pre *wpre)
-{
- struct file *h_file;
- struct dentry *dentry;
- int err;
- struct au_pin pin;
-
- err = au_reval_and_lock_fdi(file, au_reopen_nondir, /*wlock*/1);
- h_file = ERR_PTR(err);
- if (unlikely(err))
- goto out;
-
- dentry = file->f_path.dentry;
- if (do_ready) {
- err = au_ready_to_write(file, -1, &pin);
- if (unlikely(err)) {
- h_file = ERR_PTR(err);
- di_write_unlock(dentry);
- goto out_fi;
- }
- }
-
- di_downgrade_lock(dentry, /*flags*/0);
- if (wpre)
- wpre->bstart = au_fbstart(file);
- h_file = au_hf_top(file);
- get_file(h_file);
- if (wpre)
- wpre->blks = file_inode(h_file)->i_blocks;
- if (do_ready)
- au_unpin(&pin);
- di_read_unlock(dentry, /*flags*/0);
-
-out_fi:
- fi_write_unlock(file);
-out:
- return h_file;
-}
-
-static void au_write_post(struct inode *inode, struct file *h_file,
- struct au_write_pre *wpre, ssize_t written)
-{
- struct inode *h_inode;
-
- au_cpup_attr_timesizes(inode);
- AuDebugOn(au_ibstart(inode) != wpre->bstart);
- h_inode = file_inode(h_file);
- inode->i_mode = h_inode->i_mode;
- ii_write_unlock(inode);
- fput(h_file);
-
- /* AuDbg("blks %llu, %llu\n", (u64)blks, (u64)h_inode->i_blocks); */
- if (written > 0)
- au_fhsm_wrote(inode->i_sb, wpre->bstart,
- /*force*/h_inode->i_blocks > wpre->blks);
-}
-
-static ssize_t aufs_read(struct file *file, char __user *buf, size_t count,
- loff_t *ppos)
-{
- ssize_t err;
- struct inode *inode;
- struct file *h_file;
- struct super_block *sb;
-
- inode = file_inode(file);
- sb = inode->i_sb;
- si_read_lock(sb, AuLock_FLUSH | AuLock_NOPLMW);
-
- h_file = au_read_pre(file, /*keep_fi*/0);
- err = PTR_ERR(h_file);
- if (IS_ERR(h_file))
- goto out;
-
- /* filedata may be obsoleted by concurrent copyup, but no problem */
- err = vfsub_read_u(h_file, buf, count, ppos);
- /* todo: necessary? */
- /* file->f_ra = h_file->f_ra; */
- au_read_post(inode, h_file);
-
-out:
- si_read_unlock(sb);
- return err;
-}
-
-/*
- * todo: very ugly
- * it locks both of i_mutex and si_rwsem for read in safe.
- * if the plink maintenance mode continues forever (that is the problem),
- * may loop forever.
- */
-static void au_mtx_and_read_lock(struct inode *inode)
-{
- int err;
- struct super_block *sb = inode->i_sb;
-
- while (1) {
- mutex_lock(&inode->i_mutex);
- err = si_read_lock(sb, AuLock_FLUSH | AuLock_NOPLM);
- if (!err)
- break;
- mutex_unlock(&inode->i_mutex);
- si_read_lock(sb, AuLock_NOPLMW);
- si_read_unlock(sb);
- }
-}
-
-static ssize_t aufs_write(struct file *file, const char __user *ubuf,
- size_t count, loff_t *ppos)
-{
- ssize_t err;
- struct au_write_pre wpre;
- struct inode *inode;
- struct file *h_file;
- char __user *buf = (char __user *)ubuf;
-
- inode = file_inode(file);
- au_mtx_and_read_lock(inode);
-
- h_file = au_write_pre(file, /*do_ready*/1, &wpre);
- err = PTR_ERR(h_file);
- if (IS_ERR(h_file))
- goto out;
-
- err = vfsub_write_u(h_file, buf, count, ppos);
- au_write_post(inode, h_file, &wpre, err);
-
-out:
- si_read_unlock(inode->i_sb);
- mutex_unlock(&inode->i_mutex);
- return err;
-}
-
-static ssize_t au_do_iter(struct file *h_file, int rw, struct kiocb *kio,
- struct iov_iter *iov_iter)
-{
- ssize_t err;
- struct file *file;
- ssize_t (*iter)(struct kiocb *, struct iov_iter *);
-
- err = security_file_permission(h_file, rw);
- if (unlikely(err))
- goto out;
-
- err = -ENOSYS;
- iter = NULL;
- if (rw == MAY_READ)
- iter = h_file->f_op->read_iter;
- else if (rw == MAY_WRITE)
- iter = h_file->f_op->write_iter;
-
- file = kio->ki_filp;
- kio->ki_filp = h_file;
- if (iter) {
- lockdep_off();
- err = iter(kio, iov_iter);
- lockdep_on();
- } else
- /* currently there is no such fs */
- WARN_ON_ONCE(1);
- kio->ki_filp = file;
-
-out:
- return err;
-}
-
-static ssize_t aufs_read_iter(struct kiocb *kio, struct iov_iter *iov_iter)
-{
- ssize_t err;
- struct file *file, *h_file;
- struct inode *inode;
- struct super_block *sb;
-
- file = kio->ki_filp;
- inode = file_inode(file);
- sb = inode->i_sb;
- si_read_lock(sb, AuLock_FLUSH | AuLock_NOPLMW);
-
- h_file = au_read_pre(file, /*keep_fi*/0);
- err = PTR_ERR(h_file);
- if (IS_ERR(h_file))
- goto out;
-
- err = au_do_iter(h_file, MAY_READ, kio, iov_iter);
- /* todo: necessary? */
- /* file->f_ra = h_file->f_ra; */
- au_read_post(inode, h_file);
-
-out:
- si_read_unlock(sb);
- return err;
-}
-
-static ssize_t aufs_write_iter(struct kiocb *kio, struct iov_iter *iov_iter)
-{
- ssize_t err;
- struct au_write_pre wpre;
- struct inode *inode;
- struct file *file, *h_file;
-
- file = kio->ki_filp;
- inode = file_inode(file);
- au_mtx_and_read_lock(inode);
-
- h_file = au_write_pre(file, /*do_ready*/1, &wpre);
- err = PTR_ERR(h_file);
- if (IS_ERR(h_file))
- goto out;
-
- err = au_do_iter(h_file, MAY_WRITE, kio, iov_iter);
- au_write_post(inode, h_file, &wpre, err);
-
-out:
- si_read_unlock(inode->i_sb);
- mutex_unlock(&inode->i_mutex);
- return err;
-}
-
-static ssize_t aufs_splice_read(struct file *file, loff_t *ppos,
- struct pipe_inode_info *pipe, size_t len,
- unsigned int flags)
-{
- ssize_t err;
- struct file *h_file;
- struct inode *inode;
- struct super_block *sb;
-
- inode = file_inode(file);
- sb = inode->i_sb;
- si_read_lock(sb, AuLock_FLUSH | AuLock_NOPLMW);
-
- h_file = au_read_pre(file, /*keep_fi*/1);
- err = PTR_ERR(h_file);
- if (IS_ERR(h_file))
- goto out;
-
- if (au_test_loopback_kthread()) {
- au_warn_loopback(h_file->f_path.dentry->d_sb);
- if (file->f_mapping != h_file->f_mapping) {
- file->f_mapping = h_file->f_mapping;
- smp_mb(); /* unnecessary? */
- }
- }
- fi_read_unlock(file);
-
- err = vfsub_splice_to(h_file, ppos, pipe, len, flags);
- /* todo: necessasry? */
- /* file->f_ra = h_file->f_ra; */
- au_read_post(inode, h_file);
-
-out:
- si_read_unlock(sb);
- return err;
-}
-
-static ssize_t
-aufs_splice_write(struct pipe_inode_info *pipe, struct file *file, loff_t *ppos,
- size_t len, unsigned int flags)
-{
- ssize_t err;
- struct au_write_pre wpre;
- struct inode *inode;
- struct file *h_file;
-
- inode = file_inode(file);
- au_mtx_and_read_lock(inode);
-
- h_file = au_write_pre(file, /*do_ready*/1, &wpre);
- err = PTR_ERR(h_file);
- if (IS_ERR(h_file))
- goto out;
-
- err = vfsub_splice_from(pipe, h_file, ppos, len, flags);
- au_write_post(inode, h_file, &wpre, err);
-
-out:
- si_read_unlock(inode->i_sb);
- mutex_unlock(&inode->i_mutex);
- return err;
-}
-
-static long aufs_fallocate(struct file *file, int mode, loff_t offset,
- loff_t len)
-{
- long err;
- struct au_write_pre wpre;
- struct inode *inode;
- struct file *h_file;
-
- inode = file_inode(file);
- au_mtx_and_read_lock(inode);
-
- h_file = au_write_pre(file, /*do_ready*/1, &wpre);
- err = PTR_ERR(h_file);
- if (IS_ERR(h_file))
- goto out;
-
- lockdep_off();
- err = vfs_fallocate(h_file, mode, offset, len);
- lockdep_on();
- au_write_post(inode, h_file, &wpre, /*written*/1);
-
-out:
- si_read_unlock(inode->i_sb);
- mutex_unlock(&inode->i_mutex);
- return err;
-}
-
-/* ---------------------------------------------------------------------- */
-
-/*
- * The locking order around current->mmap_sem.
- * - in most and regular cases
- * file I/O syscall -- aufs_read() or something
- * -- si_rwsem for read -- mmap_sem
- * (Note that [fdi]i_rwsem are released before mmap_sem).
- * - in mmap case
- * mmap(2) -- mmap_sem -- aufs_mmap() -- si_rwsem for read -- [fdi]i_rwsem
- * This AB-BA order is definitly bad, but is not a problem since "si_rwsem for
- * read" allows muliple processes to acquire it and [fdi]i_rwsem are not held in
- * file I/O. Aufs needs to stop lockdep in aufs_mmap() though.
- * It means that when aufs acquires si_rwsem for write, the process should never
- * acquire mmap_sem.
- *
- * Actually aufs_iterate() holds [fdi]i_rwsem before mmap_sem, but this is not a
- * problem either since any directory is not able to be mmap-ed.
- * The similar scenario is applied to aufs_readlink() too.
- */
-
-#if 0 /* stop calling security_file_mmap() */
-/* cf. linux/include/linux/mman.h: calc_vm_prot_bits() */
-#define AuConv_VM_PROT(f, b) _calc_vm_trans(f, VM_##b, PROT_##b)
-
-static unsigned long au_arch_prot_conv(unsigned long flags)
-{
- /* currently ppc64 only */
-#ifdef CONFIG_PPC64
- /* cf. linux/arch/powerpc/include/asm/mman.h */
- AuDebugOn(arch_calc_vm_prot_bits(-1) != VM_SAO);
- return AuConv_VM_PROT(flags, SAO);
-#else
- AuDebugOn(arch_calc_vm_prot_bits(-1));
- return 0;
-#endif
-}
-
-static unsigned long au_prot_conv(unsigned long flags)
-{
- return AuConv_VM_PROT(flags, READ)
- | AuConv_VM_PROT(flags, WRITE)
- | AuConv_VM_PROT(flags, EXEC)
- | au_arch_prot_conv(flags);
-}
-
-/* cf. linux/include/linux/mman.h: calc_vm_flag_bits() */
-#define AuConv_VM_MAP(f, b) _calc_vm_trans(f, VM_##b, MAP_##b)
-
-static unsigned long au_flag_conv(unsigned long flags)
-{
- return AuConv_VM_MAP(flags, GROWSDOWN)
- | AuConv_VM_MAP(flags, DENYWRITE)
- | AuConv_VM_MAP(flags, LOCKED);
-}
-#endif
-
-static int aufs_mmap(struct file *file, struct vm_area_struct *vma)
-{
- int err;
- const unsigned char wlock
- = (file->f_mode & FMODE_WRITE) && (vma->vm_flags & VM_SHARED);
- struct super_block *sb;
- struct file *h_file;
- struct inode *inode;
-
- AuDbgVmRegion(file, vma);
-
- inode = file_inode(file);
- sb = inode->i_sb;
- lockdep_off();
- si_read_lock(sb, AuLock_NOPLMW);
-
- h_file = au_write_pre(file, wlock, /*wpre*/NULL);
- lockdep_on();
- err = PTR_ERR(h_file);
- if (IS_ERR(h_file))
- goto out;
-
- err = 0;
- au_set_mmapped(file);
- au_vm_file_reset(vma, h_file);
- /*
- * we cannot call security_mmap_file() here since it may acquire
- * mmap_sem or i_mutex.
- *
- * err = security_mmap_file(h_file, au_prot_conv(vma->vm_flags),
- * au_flag_conv(vma->vm_flags));
- */
- if (!err)
- err = h_file->f_op->mmap(h_file, vma);
- if (!err) {
- au_vm_prfile_set(vma, file);
- fsstack_copy_attr_atime(inode, file_inode(h_file));
- goto out_fput; /* success */
- }
- au_unset_mmapped(file);
- au_vm_file_reset(vma, file);
-
-out_fput:
- lockdep_off();
- ii_write_unlock(inode);
- lockdep_on();
- fput(h_file);
-out:
- lockdep_off();
- si_read_unlock(sb);
- lockdep_on();
- AuTraceErr(err);
- return err;
-}
-
-/* ---------------------------------------------------------------------- */
-
-static int aufs_fsync_nondir(struct file *file, loff_t start, loff_t end,
- int datasync)
-{
- int err;
- struct au_write_pre wpre;
- struct inode *inode;
- struct file *h_file;
-
- err = 0; /* -EBADF; */ /* posix? */
- if (unlikely(!(file->f_mode & FMODE_WRITE)))
- goto out;
-
- inode = file_inode(file);
- au_mtx_and_read_lock(inode);
-
- h_file = au_write_pre(file, /*do_ready*/1, &wpre);
- err = PTR_ERR(h_file);
- if (IS_ERR(h_file))
- goto out_unlock;
-
- err = vfsub_fsync(h_file, &h_file->f_path, datasync);
- au_write_post(inode, h_file, &wpre, /*written*/0);
-
-out_unlock:
- si_read_unlock(inode->i_sb);
- mutex_unlock(&inode->i_mutex);
-out:
- return err;
-}
-
-/* no one supports this operation, currently */
-#if 0
-static int aufs_aio_fsync_nondir(struct kiocb *kio, int datasync)
-{
- int err;
- struct au_write_pre wpre;
- struct inode *inode;
- struct file *file, *h_file;
-
- err = 0; /* -EBADF; */ /* posix? */
- if (unlikely(!(file->f_mode & FMODE_WRITE)))
- goto out;
-
- file = kio->ki_filp;
- inode = file_inode(file);
- au_mtx_and_read_lock(inode);
-
- h_file = au_write_pre(file, /*do_ready*/1, &wpre);
- err = PTR_ERR(h_file);
- if (IS_ERR(h_file))
- goto out_unlock;
-
- err = -ENOSYS;
- h_file = au_hf_top(file);
- if (h_file->f_op->aio_fsync) {
- struct mutex *h_mtx;
-
- h_mtx = &file_inode(h_file)->i_mutex;
- if (!is_sync_kiocb(kio)) {
- get_file(h_file);
- fput(file);
- }
- kio->ki_filp = h_file;
- err = h_file->f_op->aio_fsync(kio, datasync);
- mutex_lock_nested(h_mtx, AuLsc_I_CHILD);
- if (!err)
- vfsub_update_h_iattr(&h_file->f_path, /*did*/NULL);
- /*ignore*/
- mutex_unlock(h_mtx);
- }
- au_write_post(inode, h_file, &wpre, /*written*/0);
-
-out_unlock:
- si_read_unlock(inode->sb);
- mutex_unlock(&inode->i_mutex);
-out:
- return err;
-}
-#endif
-
-static int aufs_fasync(int fd, struct file *file, int flag)
-{
- int err;
- struct file *h_file;
- struct super_block *sb;
-
- sb = file->f_path.dentry->d_sb;
- si_read_lock(sb, AuLock_FLUSH | AuLock_NOPLMW);
-
- h_file = au_read_pre(file, /*keep_fi*/0);
- err = PTR_ERR(h_file);
- if (IS_ERR(h_file))
- goto out;
-
- if (h_file->f_op->fasync)
- err = h_file->f_op->fasync(fd, h_file, flag);
- fput(h_file); /* instead of au_read_post() */
-
-out:
- si_read_unlock(sb);
- return err;
-}
-
-static int aufs_setfl(struct file *file, unsigned long arg)
-{
- int err;
- struct file *h_file;
- struct super_block *sb;
-
- sb = file->f_path.dentry->d_sb;
- si_read_lock(sb, AuLock_FLUSH | AuLock_NOPLMW);
-
- h_file = au_read_pre(file, /*keep_fi*/0);
- err = PTR_ERR(h_file);
- if (IS_ERR(h_file))
- goto out;
-
- arg |= vfsub_file_flags(file) & FASYNC; /* stop calling h_file->fasync */
- err = setfl(/*unused fd*/-1, h_file, arg);
- fput(h_file); /* instead of au_read_post() */
-
-out:
- si_read_unlock(sb);
- return err;
-}
-
-/* ---------------------------------------------------------------------- */
-
-/* no one supports this operation, currently */
-#if 0
-static ssize_t aufs_sendpage(struct file *file, struct page *page, int offset,
- size_t len, loff_t *pos, int more)
-{
-}
-#endif
-
-/* ---------------------------------------------------------------------- */
-
-const struct file_operations aufs_file_fop = {
- .owner = THIS_MODULE,
-
- .llseek = default_llseek,
-
- .read = aufs_read,
- .write = aufs_write,
- .read_iter = aufs_read_iter,
- .write_iter = aufs_write_iter,
-
-#ifdef CONFIG_AUFS_POLL
- .poll = aufs_poll,
-#endif
- .unlocked_ioctl = aufs_ioctl_nondir,
-#ifdef CONFIG_COMPAT
- .compat_ioctl = aufs_compat_ioctl_nondir,
-#endif
- .mmap = aufs_mmap,
- .open = aufs_open_nondir,
- .flush = aufs_flush_nondir,
- .release = aufs_release_nondir,
- .fsync = aufs_fsync_nondir,
- /* .aio_fsync = aufs_aio_fsync_nondir, */
- .fasync = aufs_fasync,
- /* .sendpage = aufs_sendpage, */
- .setfl = aufs_setfl,
- .splice_write = aufs_splice_write,
- .splice_read = aufs_splice_read,
-#if 0
- .aio_splice_write = aufs_aio_splice_write,
- .aio_splice_read = aufs_aio_splice_read,
-#endif
- .fallocate = aufs_fallocate
-};