linux/fs/orangefs/inode.c
Al Viro 74f68fce2a orangefs: make pvfs2_inode_read() take iov_iter
... and make the only caller use page-backed iov_iter,
getting rid of kmap/kunmap *and* of the bug with
attempted use of iovec-backed copy_page_to_iter()
on a kernel pointer.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
2015-11-13 11:36:31 -05:00

467 lines
12 KiB
C

/*
* (C) 2001 Clemson University and The University of Chicago
*
* See COPYING in top-level directory.
*/
/*
* Linux VFS inode operations.
*/
#include "protocol.h"
#include "pvfs2-kernel.h"
#include "pvfs2-bufmap.h"
static int read_one_page(struct page *page)
{
int ret;
int max_block;
ssize_t bytes_read = 0;
struct inode *inode = page->mapping->host;
const __u32 blocksize = PAGE_CACHE_SIZE; /* inode->i_blksize */
const __u32 blockbits = PAGE_CACHE_SHIFT; /* inode->i_blkbits */
struct iov_iter to;
struct bio_vec bv = {.bv_page = page, .bv_len = PAGE_SIZE};
iov_iter_bvec(&to, ITER_BVEC | READ, &bv, 1, PAGE_SIZE);
gossip_debug(GOSSIP_INODE_DEBUG,
"pvfs2_readpage called with page %p\n",
page);
max_block = ((inode->i_size / blocksize) + 1);
if (page->index < max_block) {
loff_t blockptr_offset = (((loff_t) page->index) << blockbits);
bytes_read = pvfs2_inode_read(inode,
&to,
&blockptr_offset,
inode->i_size);
}
/* this will only zero remaining unread portions of the page data */
iov_iter_zero(~0U, &to);
/* takes care of potential aliasing */
flush_dcache_page(page);
if (bytes_read < 0) {
ret = bytes_read;
SetPageError(page);
} else {
SetPageUptodate(page);
if (PageError(page))
ClearPageError(page);
ret = 0;
}
/* unlock the page after the ->readpage() routine completes */
unlock_page(page);
return ret;
}
static int pvfs2_readpage(struct file *file, struct page *page)
{
return read_one_page(page);
}
static int pvfs2_readpages(struct file *file,
struct address_space *mapping,
struct list_head *pages,
unsigned nr_pages)
{
int page_idx;
int ret;
gossip_debug(GOSSIP_INODE_DEBUG, "pvfs2_readpages called\n");
for (page_idx = 0; page_idx < nr_pages; page_idx++) {
struct page *page;
page = list_entry(pages->prev, struct page, lru);
list_del(&page->lru);
if (!add_to_page_cache(page,
mapping,
page->index,
GFP_KERNEL)) {
ret = read_one_page(page);
gossip_debug(GOSSIP_INODE_DEBUG,
"failure adding page to cache, read_one_page returned: %d\n",
ret);
} else {
page_cache_release(page);
}
}
BUG_ON(!list_empty(pages));
return 0;
}
static void pvfs2_invalidatepage(struct page *page,
unsigned int offset,
unsigned int length)
{
gossip_debug(GOSSIP_INODE_DEBUG,
"pvfs2_invalidatepage called on page %p "
"(offset is %u)\n",
page,
offset);
ClearPageUptodate(page);
ClearPageMappedToDisk(page);
return;
}
static int pvfs2_releasepage(struct page *page, gfp_t foo)
{
gossip_debug(GOSSIP_INODE_DEBUG,
"pvfs2_releasepage called on page %p\n",
page);
return 0;
}
/*
* Having a direct_IO entry point in the address_space_operations
* struct causes the kernel to allows us to use O_DIRECT on
* open. Nothing will ever call this thing, but in the future we
* will need to be able to use O_DIRECT on open in order to support
* AIO. Modeled after NFS, they do this too.
*/
/*
* static ssize_t pvfs2_direct_IO(int rw,
* struct kiocb *iocb,
* struct iov_iter *iter,
* loff_t offset)
*{
* gossip_debug(GOSSIP_INODE_DEBUG,
* "pvfs2_direct_IO: %s\n",
* iocb->ki_filp->f_path.dentry->d_name.name);
*
* return -EINVAL;
*}
*/
struct backing_dev_info pvfs2_backing_dev_info = {
.name = "pvfs2",
.ra_pages = 0,
.capabilities = BDI_CAP_NO_ACCT_DIRTY | BDI_CAP_NO_WRITEBACK,
};
/** PVFS2 implementation of address space operations */
const struct address_space_operations pvfs2_address_operations = {
.readpage = pvfs2_readpage,
.readpages = pvfs2_readpages,
.invalidatepage = pvfs2_invalidatepage,
.releasepage = pvfs2_releasepage,
/* .direct_IO = pvfs2_direct_IO */
};
static int pvfs2_setattr_size(struct inode *inode, struct iattr *iattr)
{
struct pvfs2_inode_s *pvfs2_inode = PVFS2_I(inode);
struct pvfs2_kernel_op_s *new_op;
loff_t orig_size = i_size_read(inode);
int ret = -EINVAL;
gossip_debug(GOSSIP_INODE_DEBUG,
"%s: %pU: Handle is %pU | fs_id %d | size is %llu\n",
__func__,
get_khandle_from_ino(inode),
&pvfs2_inode->refn.khandle,
pvfs2_inode->refn.fs_id,
iattr->ia_size);
truncate_setsize(inode, iattr->ia_size);
new_op = op_alloc(PVFS2_VFS_OP_TRUNCATE);
if (!new_op)
return -ENOMEM;
new_op->upcall.req.truncate.refn = pvfs2_inode->refn;
new_op->upcall.req.truncate.size = (__s64) iattr->ia_size;
ret = service_operation(new_op, __func__,
get_interruptible_flag(inode));
/*
* the truncate has no downcall members to retrieve, but
* the status value tells us if it went through ok or not
*/
gossip_debug(GOSSIP_INODE_DEBUG,
"pvfs2: pvfs2_truncate got return value of %d\n",
ret);
op_release(new_op);
if (ret != 0)
return ret;
/*
* Only change the c/mtime if we are changing the size or we are
* explicitly asked to change it. This handles the semantic difference
* between truncate() and ftruncate() as implemented in the VFS.
*
* The regular truncate() case without ATTR_CTIME and ATTR_MTIME is a
* special case where we need to update the times despite not having
* these flags set. For all other operations the VFS set these flags
* explicitly if it wants a timestamp update.
*/
if (orig_size != i_size_read(inode) &&
!(iattr->ia_valid & (ATTR_CTIME | ATTR_MTIME))) {
iattr->ia_ctime = iattr->ia_mtime =
current_fs_time(inode->i_sb);
iattr->ia_valid |= ATTR_CTIME | ATTR_MTIME;
}
return ret;
}
/*
* Change attributes of an object referenced by dentry.
*/
int pvfs2_setattr(struct dentry *dentry, struct iattr *iattr)
{
int ret = -EINVAL;
struct inode *inode = dentry->d_inode;
gossip_debug(GOSSIP_INODE_DEBUG,
"pvfs2_setattr: called on %s\n",
dentry->d_name.name);
ret = inode_change_ok(inode, iattr);
if (ret)
goto out;
if ((iattr->ia_valid & ATTR_SIZE) &&
iattr->ia_size != i_size_read(inode)) {
ret = pvfs2_setattr_size(inode, iattr);
if (ret)
goto out;
}
setattr_copy(inode, iattr);
mark_inode_dirty(inode);
ret = pvfs2_inode_setattr(inode, iattr);
gossip_debug(GOSSIP_INODE_DEBUG,
"pvfs2_setattr: inode_setattr returned %d\n",
ret);
if (!ret && (iattr->ia_valid & ATTR_MODE))
/* change mod on a file that has ACLs */
ret = posix_acl_chmod(inode, inode->i_mode);
out:
gossip_debug(GOSSIP_INODE_DEBUG, "pvfs2_setattr: returning %d\n", ret);
return ret;
}
/*
* Obtain attributes of an object given a dentry
*/
int pvfs2_getattr(struct vfsmount *mnt,
struct dentry *dentry,
struct kstat *kstat)
{
int ret = -ENOENT;
struct inode *inode = dentry->d_inode;
struct pvfs2_inode_s *pvfs2_inode = NULL;
gossip_debug(GOSSIP_INODE_DEBUG,
"pvfs2_getattr: called on %s\n",
dentry->d_name.name);
/*
* Similar to the above comment, a getattr also expects that all
* fields/attributes of the inode would be refreshed. So again, we
* dont have too much of a choice but refresh all the attributes.
*/
ret = pvfs2_inode_getattr(inode, PVFS_ATTR_SYS_ALL_NOHINT);
if (ret == 0) {
generic_fillattr(inode, kstat);
/* override block size reported to stat */
pvfs2_inode = PVFS2_I(inode);
kstat->blksize = pvfs2_inode->blksize;
} else {
/* assume an I/O error and flag inode as bad */
gossip_debug(GOSSIP_INODE_DEBUG,
"%s:%s:%d calling make bad inode\n",
__FILE__,
__func__,
__LINE__);
pvfs2_make_bad_inode(inode);
}
return ret;
}
/* PVFS2 implementation of VFS inode operations for files */
struct inode_operations pvfs2_file_inode_operations = {
.get_acl = pvfs2_get_acl,
.set_acl = pvfs2_set_acl,
.setattr = pvfs2_setattr,
.getattr = pvfs2_getattr,
.setxattr = generic_setxattr,
.getxattr = generic_getxattr,
.listxattr = pvfs2_listxattr,
.removexattr = generic_removexattr,
};
static int pvfs2_init_iops(struct inode *inode)
{
inode->i_mapping->a_ops = &pvfs2_address_operations;
switch (inode->i_mode & S_IFMT) {
case S_IFREG:
inode->i_op = &pvfs2_file_inode_operations;
inode->i_fop = &pvfs2_file_operations;
inode->i_blkbits = PAGE_CACHE_SHIFT;
break;
case S_IFLNK:
inode->i_op = &pvfs2_symlink_inode_operations;
break;
case S_IFDIR:
inode->i_op = &pvfs2_dir_inode_operations;
inode->i_fop = &pvfs2_dir_operations;
break;
default:
gossip_debug(GOSSIP_INODE_DEBUG,
"%s: unsupported mode\n",
__func__);
return -EINVAL;
}
return 0;
}
/*
* Given a PVFS2 object identifier (fsid, handle), convert it into a ino_t type
* that will be used as a hash-index from where the handle will
* be searched for in the VFS hash table of inodes.
*/
static inline ino_t pvfs2_handle_hash(struct pvfs2_object_kref *ref)
{
if (!ref)
return 0;
return pvfs2_khandle_to_ino(&(ref->khandle));
}
/*
* Called to set up an inode from iget5_locked.
*/
static int pvfs2_set_inode(struct inode *inode, void *data)
{
struct pvfs2_object_kref *ref = (struct pvfs2_object_kref *) data;
struct pvfs2_inode_s *pvfs2_inode = NULL;
/* Make sure that we have sane parameters */
if (!data || !inode)
return 0;
pvfs2_inode = PVFS2_I(inode);
if (!pvfs2_inode)
return 0;
pvfs2_inode->refn.fs_id = ref->fs_id;
pvfs2_inode->refn.khandle = ref->khandle;
return 0;
}
/*
* Called to determine if handles match.
*/
static int pvfs2_test_inode(struct inode *inode, void *data)
{
struct pvfs2_object_kref *ref = (struct pvfs2_object_kref *) data;
struct pvfs2_inode_s *pvfs2_inode = NULL;
pvfs2_inode = PVFS2_I(inode);
return (!PVFS_khandle_cmp(&(pvfs2_inode->refn.khandle), &(ref->khandle))
&& pvfs2_inode->refn.fs_id == ref->fs_id);
}
/*
* Front-end to lookup the inode-cache maintained by the VFS using the PVFS2
* file handle.
*
* @sb: the file system super block instance.
* @ref: The PVFS2 object for which we are trying to locate an inode structure.
*/
struct inode *pvfs2_iget(struct super_block *sb, struct pvfs2_object_kref *ref)
{
struct inode *inode = NULL;
unsigned long hash;
int error;
hash = pvfs2_handle_hash(ref);
inode = iget5_locked(sb, hash, pvfs2_test_inode, pvfs2_set_inode, ref);
if (!inode || !(inode->i_state & I_NEW))
return inode;
error = pvfs2_inode_getattr(inode, PVFS_ATTR_SYS_ALL_NOHINT);
if (error) {
iget_failed(inode);
return ERR_PTR(error);
}
inode->i_ino = hash; /* needed for stat etc */
pvfs2_init_iops(inode);
unlock_new_inode(inode);
gossip_debug(GOSSIP_INODE_DEBUG,
"iget handle %pU, fsid %d hash %ld i_ino %lu\n",
&ref->khandle,
ref->fs_id,
hash,
inode->i_ino);
return inode;
}
/*
* Allocate an inode for a newly created file and insert it into the inode hash.
*/
struct inode *pvfs2_new_inode(struct super_block *sb, struct inode *dir,
int mode, dev_t dev, struct pvfs2_object_kref *ref)
{
unsigned long hash = pvfs2_handle_hash(ref);
struct inode *inode;
int error;
gossip_debug(GOSSIP_INODE_DEBUG,
"pvfs2_get_custom_inode_common: called\n"
"(sb is %p | MAJOR(dev)=%u | MINOR(dev)=%u mode=%o)\n",
sb,
MAJOR(dev),
MINOR(dev),
mode);
inode = new_inode(sb);
if (!inode)
return NULL;
pvfs2_set_inode(inode, ref);
inode->i_ino = hash; /* needed for stat etc */
error = pvfs2_inode_getattr(inode, PVFS_ATTR_SYS_ALL_NOHINT);
if (error)
goto out_iput;
pvfs2_init_iops(inode);
inode->i_mode = mode;
inode->i_uid = current_fsuid();
inode->i_gid = current_fsgid();
inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
inode->i_size = PAGE_CACHE_SIZE;
inode->i_rdev = dev;
error = insert_inode_locked4(inode, hash, pvfs2_test_inode, ref);
if (error < 0)
goto out_iput;
gossip_debug(GOSSIP_INODE_DEBUG,
"Initializing ACL's for inode %pU\n",
get_khandle_from_ino(inode));
pvfs2_init_acl(inode, dir);
return inode;
out_iput:
iput(inode);
return ERR_PTR(error);
}