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exofs: dir_inode and directory operations 

implementation of directory and inode operations.

* A directory is treated as a file, and essentially contains a list
  of <file name, inode #> pairs for files that are found in that
  directory. The object IDs correspond to the files' inode numbers
  and are allocated using a 64bit incrementing global counter.
* Each file's control block (AKA on-disk inode) is stored in its
  object's attributes. This applies to both regular files and other
  types (directories, device files, symlinks, etc.).

Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
This commit is contained in:
Boaz Harrosh 2008-10-28 15:38:12 +02:00
parent beaec07ba6
commit e6af00f1d1
5 changed files with 1298 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
fs/exofs/Kbuild
View File

@ -12,5 +12,5 @@
# Kbuild - Gets included from the Kernels Makefile and build system
#
exofs-y := osd.o inode.o file.o symlink.o
exofs-y := osd.o inode.o file.o symlink.o namei.o dir.o
obj-$(CONFIG_EXOFS_FS) += exofs.o

657
fs/exofs/dir.c Normal file
View File

@ -0,0 +1,657 @@
/*
* Copyright (C) 2005, 2006
* Avishay Traeger (avishay@gmail.com) (avishay@il.ibm.com)
* Copyright (C) 2005, 2006
* International Business Machines
* Copyright (C) 2008, 2009
* Boaz Harrosh <bharrosh@panasas.com>
*
* Copyrights for code taken from ext2:
* Copyright (C) 1992, 1993, 1994, 1995
* Remy Card (card@masi.ibp.fr)
* Laboratoire MASI - Institut Blaise Pascal
* Universite Pierre et Marie Curie (Paris VI)
* from
* linux/fs/minix/inode.c
* Copyright (C) 1991, 1992 Linus Torvalds
*
* This file is part of exofs.
*
* exofs 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. Since it is based on ext2, and the only
* valid version of GPL for the Linux kernel is version 2, the only valid
* version of GPL for exofs is version 2.
*
* exofs 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 exofs; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "exofs.h"
static inline unsigned exofs_chunk_size(struct inode *inode)
{
return inode->i_sb->s_blocksize;
}
static inline void exofs_put_page(struct page *page)
{
kunmap(page);
page_cache_release(page);
}
/* Accesses dir's inode->i_size must be called under inode lock */
static inline unsigned long dir_pages(struct inode *inode)
{
return (inode->i_size + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
}
static unsigned exofs_last_byte(struct inode *inode, unsigned long page_nr)
{
loff_t last_byte = inode->i_size;
last_byte -= page_nr << PAGE_CACHE_SHIFT;
if (last_byte > PAGE_CACHE_SIZE)
last_byte = PAGE_CACHE_SIZE;
return last_byte;
}
static int exofs_commit_chunk(struct page *page, loff_t pos, unsigned len)
{
struct address_space *mapping = page->mapping;
struct inode *dir = mapping->host;
int err = 0;
dir->i_version++;
if (!PageUptodate(page))
SetPageUptodate(page);
if (pos+len > dir->i_size) {
i_size_write(dir, pos+len);
mark_inode_dirty(dir);
}
set_page_dirty(page);
if (IS_DIRSYNC(dir))
err = write_one_page(page, 1);
else
unlock_page(page);
return err;
}
static void exofs_check_page(struct page *page)
{
struct inode *dir = page->mapping->host;
unsigned chunk_size = exofs_chunk_size(dir);
char *kaddr = page_address(page);
unsigned offs, rec_len;
unsigned limit = PAGE_CACHE_SIZE;
struct exofs_dir_entry *p;
char *error;
/* if the page is the last one in the directory */
if ((dir->i_size >> PAGE_CACHE_SHIFT) == page->index) {
limit = dir->i_size & ~PAGE_CACHE_MASK;
if (limit & (chunk_size - 1))
goto Ebadsize;
if (!limit)
goto out;
}
for (offs = 0; offs <= limit - EXOFS_DIR_REC_LEN(1); offs += rec_len) {
p = (struct exofs_dir_entry *)(kaddr + offs);
rec_len = le16_to_cpu(p->rec_len);
if (rec_len < EXOFS_DIR_REC_LEN(1))
goto Eshort;
if (rec_len & 3)
goto Ealign;
if (rec_len < EXOFS_DIR_REC_LEN(p->name_len))
goto Enamelen;
if (((offs + rec_len - 1) ^ offs) & ~(chunk_size-1))
goto Espan;
}
if (offs != limit)
goto Eend;
out:
SetPageChecked(page);
return;
Ebadsize:
EXOFS_ERR("ERROR [exofs_check_page]: "
"size of directory #%lu is not a multiple of chunk size",
dir->i_ino
);
goto fail;
Eshort:
error = "rec_len is smaller than minimal";
goto bad_entry;
Ealign:
error = "unaligned directory entry";
goto bad_entry;
Enamelen:
error = "rec_len is too small for name_len";
goto bad_entry;
Espan:
error = "directory entry across blocks";
goto bad_entry;
bad_entry:
EXOFS_ERR(
"ERROR [exofs_check_page]: bad entry in directory #%lu: %s - "
"offset=%lu, inode=%llu, rec_len=%d, name_len=%d",
dir->i_ino, error, (page->index<<PAGE_CACHE_SHIFT)+offs,
_LLU(le64_to_cpu(p->inode_no)),
rec_len, p->name_len);
goto fail;
Eend:
p = (struct exofs_dir_entry *)(kaddr + offs);
EXOFS_ERR("ERROR [exofs_check_page]: "
"entry in directory #%lu spans the page boundary"
"offset=%lu, inode=%llu",
dir->i_ino, (page->index<<PAGE_CACHE_SHIFT)+offs,
_LLU(le64_to_cpu(p->inode_no)));
fail:
SetPageChecked(page);
SetPageError(page);
}
static struct page *exofs_get_page(struct inode *dir, unsigned long n)
{
struct address_space *mapping = dir->i_mapping;
struct page *page = read_mapping_page(mapping, n, NULL);
if (!IS_ERR(page)) {
kmap(page);
if (!PageChecked(page))
exofs_check_page(page);
if (PageError(page))
goto fail;
}
return page;
fail:
exofs_put_page(page);
return ERR_PTR(-EIO);
}
static inline int exofs_match(int len, const unsigned char *name,
struct exofs_dir_entry *de)
{
if (len != de->name_len)
return 0;
if (!de->inode_no)
return 0;
return !memcmp(name, de->name, len);
}
static inline
struct exofs_dir_entry *exofs_next_entry(struct exofs_dir_entry *p)
{
return (struct exofs_dir_entry *)((char *)p + le16_to_cpu(p->rec_len));
}
static inline unsigned
exofs_validate_entry(char *base, unsigned offset, unsigned mask)
{
struct exofs_dir_entry *de = (struct exofs_dir_entry *)(base + offset);
struct exofs_dir_entry *p =
(struct exofs_dir_entry *)(base + (offset&mask));
while ((char *)p < (char *)de) {
if (p->rec_len == 0)
break;
p = exofs_next_entry(p);
}
return (char *)p - base;
}
static unsigned char exofs_filetype_table[EXOFS_FT_MAX] = {
[EXOFS_FT_UNKNOWN] = DT_UNKNOWN,
[EXOFS_FT_REG_FILE] = DT_REG,
[EXOFS_FT_DIR] = DT_DIR,
[EXOFS_FT_CHRDEV] = DT_CHR,
[EXOFS_FT_BLKDEV] = DT_BLK,
[EXOFS_FT_FIFO] = DT_FIFO,
[EXOFS_FT_SOCK] = DT_SOCK,
[EXOFS_FT_SYMLINK] = DT_LNK,
};
#define S_SHIFT 12
static unsigned char exofs_type_by_mode[S_IFMT >> S_SHIFT] = {
[S_IFREG >> S_SHIFT] = EXOFS_FT_REG_FILE,
[S_IFDIR >> S_SHIFT] = EXOFS_FT_DIR,
[S_IFCHR >> S_SHIFT] = EXOFS_FT_CHRDEV,
[S_IFBLK >> S_SHIFT] = EXOFS_FT_BLKDEV,
[S_IFIFO >> S_SHIFT] = EXOFS_FT_FIFO,
[S_IFSOCK >> S_SHIFT] = EXOFS_FT_SOCK,
[S_IFLNK >> S_SHIFT] = EXOFS_FT_SYMLINK,
};
static inline
void exofs_set_de_type(struct exofs_dir_entry *de, struct inode *inode)
{
mode_t mode = inode->i_mode;
de->file_type = exofs_type_by_mode[(mode & S_IFMT) >> S_SHIFT];
}
static int
exofs_readdir(struct file *filp, void *dirent, filldir_t filldir)
{
loff_t pos = filp->f_pos;
struct inode *inode = filp->f_path.dentry->d_inode;
unsigned int offset = pos & ~PAGE_CACHE_MASK;
unsigned long n = pos >> PAGE_CACHE_SHIFT;
unsigned long npages = dir_pages(inode);
unsigned chunk_mask = ~(exofs_chunk_size(inode)-1);
unsigned char *types = NULL;
int need_revalidate = (filp->f_version != inode->i_version);
if (pos > inode->i_size - EXOFS_DIR_REC_LEN(1))
return 0;
types = exofs_filetype_table;
for ( ; n < npages; n++, offset = 0) {
char *kaddr, *limit;
struct exofs_dir_entry *de;
struct page *page = exofs_get_page(inode, n);
if (IS_ERR(page)) {
EXOFS_ERR("ERROR: "
"bad page in #%lu",
inode->i_ino);
filp->f_pos += PAGE_CACHE_SIZE - offset;
return PTR_ERR(page);
}
kaddr = page_address(page);
if (unlikely(need_revalidate)) {
if (offset) {
offset = exofs_validate_entry(kaddr, offset,
chunk_mask);
filp->f_pos = (n<<PAGE_CACHE_SHIFT) + offset;
}
filp->f_version = inode->i_version;
need_revalidate = 0;
}
de = (struct exofs_dir_entry *)(kaddr + offset);
limit = kaddr + exofs_last_byte(inode, n) -
EXOFS_DIR_REC_LEN(1);
for (; (char *)de <= limit; de = exofs_next_entry(de)) {
if (de->rec_len == 0) {
EXOFS_ERR("ERROR: "
"zero-length directory entry");
exofs_put_page(page);
return -EIO;
}
if (de->inode_no) {
int over;
unsigned char d_type = DT_UNKNOWN;
if (types && de->file_type < EXOFS_FT_MAX)
d_type = types[de->file_type];
offset = (char *)de - kaddr;
over = filldir(dirent, de->name, de->name_len,
(n<<PAGE_CACHE_SHIFT) | offset,
le64_to_cpu(de->inode_no),
d_type);
if (over) {
exofs_put_page(page);
return 0;
}
}
filp->f_pos += le16_to_cpu(de->rec_len);
}
exofs_put_page(page);
}
return 0;
}
struct exofs_dir_entry *exofs_find_entry(struct inode *dir,
struct dentry *dentry, struct page **res_page)
{
const unsigned char *name = dentry->d_name.name;
int namelen = dentry->d_name.len;
unsigned reclen = EXOFS_DIR_REC_LEN(namelen);
unsigned long start, n;
unsigned long npages = dir_pages(dir);
struct page *page = NULL;
struct exofs_i_info *oi = exofs_i(dir);
struct exofs_dir_entry *de;
if (npages == 0)
goto out;
*res_page = NULL;
start = oi->i_dir_start_lookup;
if (start >= npages)
start = 0;
n = start;
do {
char *kaddr;
page = exofs_get_page(dir, n);
if (!IS_ERR(page)) {
kaddr = page_address(page);
de = (struct exofs_dir_entry *) kaddr;
kaddr += exofs_last_byte(dir, n) - reclen;
while ((char *) de <= kaddr) {
if (de->rec_len == 0) {
EXOFS_ERR(
"ERROR: exofs_find_entry: "
"zero-length directory entry");
exofs_put_page(page);
goto out;
}
if (exofs_match(namelen, name, de))
goto found;
de = exofs_next_entry(de);
}
exofs_put_page(page);
}
if (++n >= npages)
n = 0;
} while (n != start);
out:
return NULL;
found:
*res_page = page;
oi->i_dir_start_lookup = n;
return de;
}
struct exofs_dir_entry *exofs_dotdot(struct inode *dir, struct page **p)
{
struct page *page = exofs_get_page(dir, 0);
struct exofs_dir_entry *de = NULL;
if (!IS_ERR(page)) {
de = exofs_next_entry(
(struct exofs_dir_entry *)page_address(page));
*p = page;
}
return de;
}
ino_t exofs_inode_by_name(struct inode *dir, struct dentry *dentry)
{
ino_t res = 0;
struct exofs_dir_entry *de;
struct page *page;
de = exofs_find_entry(dir, dentry, &page);
if (de) {
res = le64_to_cpu(de->inode_no);
exofs_put_page(page);
}
return res;
}
int exofs_set_link(struct inode *dir, struct exofs_dir_entry *de,
struct page *page, struct inode *inode)
{
loff_t pos = page_offset(page) +
(char *) de - (char *) page_address(page);
unsigned len = le16_to_cpu(de->rec_len);
int err;
lock_page(page);
err = exofs_write_begin(NULL, page->mapping, pos, len,
AOP_FLAG_UNINTERRUPTIBLE, &page, NULL);
if (err)
EXOFS_ERR("exofs_set_link: exofs_write_begin FAILD => %d\n",
err);
de->inode_no = cpu_to_le64(inode->i_ino);
exofs_set_de_type(de, inode);
if (likely(!err))
err = exofs_commit_chunk(page, pos, len);
exofs_put_page(page);
dir->i_mtime = dir->i_ctime = CURRENT_TIME;
mark_inode_dirty(dir);
return err;
}
int exofs_add_link(struct dentry *dentry, struct inode *inode)
{
struct inode *dir = dentry->d_parent->d_inode;
const unsigned char *name = dentry->d_name.name;
int namelen = dentry->d_name.len;
unsigned chunk_size = exofs_chunk_size(dir);
unsigned reclen = EXOFS_DIR_REC_LEN(namelen);
unsigned short rec_len, name_len;
struct page *page = NULL;
struct exofs_sb_info *sbi = inode->i_sb->s_fs_info;
struct exofs_dir_entry *de;
unsigned long npages = dir_pages(dir);
unsigned long n;
char *kaddr;
loff_t pos;
int err;
for (n = 0; n <= npages; n++) {
char *dir_end;
page = exofs_get_page(dir, n);
err = PTR_ERR(page);
if (IS_ERR(page))
goto out;
lock_page(page);
kaddr = page_address(page);
dir_end = kaddr + exofs_last_byte(dir, n);
de = (struct exofs_dir_entry *)kaddr;
kaddr += PAGE_CACHE_SIZE - reclen;
while ((char *)de <= kaddr) {
if ((char *)de == dir_end) {
name_len = 0;
rec_len = chunk_size;
de->rec_len = cpu_to_le16(chunk_size);
de->inode_no = 0;
goto got_it;
}
if (de->rec_len == 0) {
EXOFS_ERR("ERROR: exofs_add_link: "
"zero-length directory entry");
err = -EIO;
goto out_unlock;
}
err = -EEXIST;
if (exofs_match(namelen, name, de))
goto out_unlock;
name_len = EXOFS_DIR_REC_LEN(de->name_len);
rec_len = le16_to_cpu(de->rec_len);
if (!de->inode_no && rec_len >= reclen)
goto got_it;
if (rec_len >= name_len + reclen)
goto got_it;
de = (struct exofs_dir_entry *) ((char *) de + rec_len);
}
unlock_page(page);
exofs_put_page(page);
}
EXOFS_ERR("exofs_add_link: BAD dentry=%p or inode=%p", dentry, inode);
return -EINVAL;
got_it:
pos = page_offset(page) +
(char *)de - (char *)page_address(page);
err = exofs_write_begin(NULL, page->mapping, pos, rec_len, 0,
&page, NULL);
if (err)
goto out_unlock;
if (de->inode_no) {
struct exofs_dir_entry *de1 =
(struct exofs_dir_entry *)((char *)de + name_len);
de1->rec_len = cpu_to_le16(rec_len - name_len);
de->rec_len = cpu_to_le16(name_len);
de = de1;
}
de->name_len = namelen;
memcpy(de->name, name, namelen);
de->inode_no = cpu_to_le64(inode->i_ino);
exofs_set_de_type(de, inode);
err = exofs_commit_chunk(page, pos, rec_len);
dir->i_mtime = dir->i_ctime = CURRENT_TIME;
mark_inode_dirty(dir);
sbi->s_numfiles++;
out_put:
exofs_put_page(page);
out:
return err;
out_unlock:
unlock_page(page);
goto out_put;
}
int exofs_delete_entry(struct exofs_dir_entry *dir, struct page *page)
{
struct address_space *mapping = page->mapping;
struct inode *inode = mapping->host;
struct exofs_sb_info *sbi = inode->i_sb->s_fs_info;
char *kaddr = page_address(page);
unsigned from = ((char *)dir - kaddr) & ~(exofs_chunk_size(inode)-1);
unsigned to = ((char *)dir - kaddr) + le16_to_cpu(dir->rec_len);
loff_t pos;
struct exofs_dir_entry *pde = NULL;
struct exofs_dir_entry *de = (struct exofs_dir_entry *) (kaddr + from);
int err;
while (de < dir) {
if (de->rec_len == 0) {
EXOFS_ERR("ERROR: exofs_delete_entry:"
"zero-length directory entry");
err = -EIO;
goto out;
}
pde = de;
de = exofs_next_entry(de);
}
if (pde)
from = (char *)pde - (char *)page_address(page);
pos = page_offset(page) + from;
lock_page(page);
err = exofs_write_begin(NULL, page->mapping, pos, to - from, 0,
&page, NULL);
if (err)
EXOFS_ERR("exofs_delete_entry: exofs_write_begin FAILD => %d\n",
err);
if (pde)
pde->rec_len = cpu_to_le16(to - from);
dir->inode_no = 0;
if (likely(!err))
err = exofs_commit_chunk(page, pos, to - from);
inode->i_ctime = inode->i_mtime = CURRENT_TIME;
mark_inode_dirty(inode);
sbi->s_numfiles--;
out:
exofs_put_page(page);
return err;
}
/* kept aligned on 4 bytes */
#define THIS_DIR ".\0\0"
#define PARENT_DIR "..\0"
int exofs_make_empty(struct inode *inode, struct inode *parent)
{
struct address_space *mapping = inode->i_mapping;
struct page *page = grab_cache_page(mapping, 0);
unsigned chunk_size = exofs_chunk_size(inode);
struct exofs_dir_entry *de;
int err;
void *kaddr;
if (!page)
return -ENOMEM;
err = exofs_write_begin(NULL, page->mapping, 0, chunk_size, 0,
&page, NULL);
if (err) {
unlock_page(page);
goto fail;
}
kaddr = kmap_atomic(page, KM_USER0);
de = (struct exofs_dir_entry *)kaddr;
de->name_len = 1;
de->rec_len = cpu_to_le16(EXOFS_DIR_REC_LEN(1));
memcpy(de->name, THIS_DIR, sizeof(THIS_DIR));
de->inode_no = cpu_to_le64(inode->i_ino);
exofs_set_de_type(de, inode);
de = (struct exofs_dir_entry *)(kaddr + EXOFS_DIR_REC_LEN(1));
de->name_len = 2;
de->rec_len = cpu_to_le16(chunk_size - EXOFS_DIR_REC_LEN(1));
de->inode_no = cpu_to_le64(parent->i_ino);
memcpy(de->name, PARENT_DIR, sizeof(PARENT_DIR));
exofs_set_de_type(de, inode);
kunmap_atomic(page, KM_USER0);
err = exofs_commit_chunk(page, 0, chunk_size);
fail:
page_cache_release(page);
return err;
}
int exofs_empty_dir(struct inode *inode)
{
struct page *page = NULL;
unsigned long i, npages = dir_pages(inode);
for (i = 0; i < npages; i++) {
char *kaddr;
struct exofs_dir_entry *de;
page = exofs_get_page(inode, i);
if (IS_ERR(page))
continue;
kaddr = page_address(page);
de = (struct exofs_dir_entry *)kaddr;
kaddr += exofs_last_byte(inode, i) - EXOFS_DIR_REC_LEN(1);
while ((char *)de <= kaddr) {
if (de->rec_len == 0) {
EXOFS_ERR("ERROR: exofs_empty_dir: "
"zero-length directory entry"
"kaddr=%p, de=%p\n", kaddr, de);
goto not_empty;
}
if (de->inode_no != 0) {
/* check for . and .. */
if (de->name[0] != '.')
goto not_empty;
if (de->name_len > 2)
goto not_empty;
if (de->name_len < 2) {
if (le64_to_cpu(de->inode_no) !=
inode->i_ino)
goto not_empty;
} else if (de->name[1] != '.')
goto not_empty;
}
de = exofs_next_entry(de);
}
exofs_put_page(page);
}
return 1;
not_empty:
exofs_put_page(page);
return 0;
}
const struct file_operations exofs_dir_operations = {
.llseek = generic_file_llseek,
.read = generic_read_dir,
.readdir = exofs_readdir,
};

26
fs/exofs/exofs.h
View File

@ -124,6 +124,11 @@ static inline struct exofs_i_info *exofs_i(struct inode *inode)
return container_of(inode, struct exofs_i_info, vfs_inode);
}
/*
* Maximum count of links to a file
*/
#define EXOFS_LINK_MAX 32000
/*************************
* function declarations *
*************************/
@ -133,10 +138,27 @@ int exofs_setattr(struct dentry *, struct iattr *);
int exofs_write_begin(struct file *file, struct address_space *mapping,
loff_t pos, unsigned len, unsigned flags,
struct page **pagep, void **fsdata);
extern struct inode *exofs_iget(struct super_block *, unsigned long);
struct inode *exofs_new_inode(struct inode *, int);
/* dir.c: */
int exofs_add_link(struct dentry *, struct inode *);
ino_t exofs_inode_by_name(struct inode *, struct dentry *);
int exofs_delete_entry(struct exofs_dir_entry *, struct page *);
int exofs_make_empty(struct inode *, struct inode *);
struct exofs_dir_entry *exofs_find_entry(struct inode *, struct dentry *,
struct page **);
int exofs_empty_dir(struct inode *);
struct exofs_dir_entry *exofs_dotdot(struct inode *, struct page **);
int exofs_set_link(struct inode *, struct exofs_dir_entry *, struct page *,
struct inode *);
/*********************
* operation vectors *
*********************/
/* dir.c: */
extern const struct file_operations exofs_dir_operations;
/* file.c */
extern const struct inode_operations exofs_file_inode_operations;
extern const struct file_operations exofs_file_operations;
@ -144,6 +166,10 @@ extern const struct file_operations exofs_file_operations;
/* inode.c */
extern const struct address_space_operations exofs_aops;
/* namei.c */
extern const struct inode_operations exofs_dir_inode_operations;
extern const struct inode_operations exofs_special_inode_operations;
/* symlink.c */
extern const struct inode_operations exofs_symlink_inode_operations;
extern const struct inode_operations exofs_fast_symlink_inode_operations;

272
fs/exofs/inode.c
View File

@ -843,3 +843,275 @@ int exofs_setattr(struct dentry *dentry, struct iattr *iattr)
error = inode_setattr(inode, iattr);
return error;
}
/*
* Read an inode from the OSD, and return it as is. We also return the size
* attribute in the 'sanity' argument if we got compiled with debugging turned
* on.
*/
static int exofs_get_inode(struct super_block *sb, struct exofs_i_info *oi,
struct exofs_fcb *inode, uint64_t *sanity)
{
struct exofs_sb_info *sbi = sb->s_fs_info;
struct osd_request *or;
struct osd_attr attr;
struct osd_obj_id obj = {sbi->s_pid,
oi->vfs_inode.i_ino + EXOFS_OBJ_OFF};
int ret;
exofs_make_credential(oi->i_cred, &obj);
or = osd_start_request(sbi->s_dev, GFP_KERNEL);
if (unlikely(!or)) {
EXOFS_ERR("exofs_get_inode: osd_start_request failed.\n");
return -ENOMEM;
}
osd_req_get_attributes(or, &obj);
/* we need the inode attribute */
osd_req_add_get_attr_list(or, &g_attr_inode_data, 1);
#ifdef EXOFS_DEBUG_OBJ_ISIZE
/* we get the size attributes to do a sanity check */
osd_req_add_get_attr_list(or, &g_attr_logical_length, 1);
#endif
ret = exofs_sync_op(or, sbi->s_timeout, oi->i_cred);
if (ret)
goto out;
attr = g_attr_inode_data;
ret = extract_attr_from_req(or, &attr);
if (ret) {
EXOFS_ERR("exofs_get_inode: extract_attr_from_req failed\n");
goto out;
}
WARN_ON(attr.len != EXOFS_INO_ATTR_SIZE);
memcpy(inode, attr.val_ptr, EXOFS_INO_ATTR_SIZE);
#ifdef EXOFS_DEBUG_OBJ_ISIZE
attr = g_attr_logical_length;
ret = extract_attr_from_req(or, &attr);
if (ret) {
EXOFS_ERR("ERROR: extract attr from or failed\n");
goto out;
}
*sanity = get_unaligned_be64(attr.val_ptr);
#endif
out:
osd_end_request(or);
return ret;
}
/*
* Fill in an inode read from the OSD and set it up for use
*/
struct inode *exofs_iget(struct super_block *sb, unsigned long ino)
{
struct exofs_i_info *oi;
struct exofs_fcb fcb;
struct inode *inode;
uint64_t uninitialized_var(sanity);
int ret;
inode = iget_locked(sb, ino);
if (!inode)
return ERR_PTR(-ENOMEM);
if (!(inode->i_state & I_NEW))
return inode;
oi = exofs_i(inode);
/* read the inode from the osd */
ret = exofs_get_inode(sb, oi, &fcb, &sanity);
if (ret)
goto bad_inode;
init_waitqueue_head(&oi->i_wq);
set_obj_created(oi);
/* copy stuff from on-disk struct to in-memory struct */
inode->i_mode = le16_to_cpu(fcb.i_mode);
inode->i_uid = le32_to_cpu(fcb.i_uid);
inode->i_gid = le32_to_cpu(fcb.i_gid);
inode->i_nlink = le16_to_cpu(fcb.i_links_count);
inode->i_ctime.tv_sec = (signed)le32_to_cpu(fcb.i_ctime);
inode->i_atime.tv_sec = (signed)le32_to_cpu(fcb.i_atime);
inode->i_mtime.tv_sec = (signed)le32_to_cpu(fcb.i_mtime);
inode->i_ctime.tv_nsec =
inode->i_atime.tv_nsec = inode->i_mtime.tv_nsec = 0;
oi->i_commit_size = le64_to_cpu(fcb.i_size);
i_size_write(inode, oi->i_commit_size);
inode->i_blkbits = EXOFS_BLKSHIFT;
inode->i_generation = le32_to_cpu(fcb.i_generation);
#ifdef EXOFS_DEBUG_OBJ_ISIZE
if ((inode->i_size != sanity) &&
(!exofs_inode_is_fast_symlink(inode))) {
EXOFS_ERR("WARNING: Size of object from inode and "
"attributes differ (%lld != %llu)\n",
inode->i_size, _LLU(sanity));
}
#endif
oi->i_dir_start_lookup = 0;
if ((inode->i_nlink == 0) && (inode->i_mode == 0)) {
ret = -ESTALE;
goto bad_inode;
}
if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
if (fcb.i_data[0])
inode->i_rdev =
old_decode_dev(le32_to_cpu(fcb.i_data[0]));
else
inode->i_rdev =
new_decode_dev(le32_to_cpu(fcb.i_data[1]));
} else {
memcpy(oi->i_data, fcb.i_data, sizeof(fcb.i_data));
}
if (S_ISREG(inode->i_mode)) {
inode->i_op = &exofs_file_inode_operations;
inode->i_fop = &exofs_file_operations;
inode->i_mapping->a_ops = &exofs_aops;
} else if (S_ISDIR(inode->i_mode)) {
inode->i_op = &exofs_dir_inode_operations;
inode->i_fop = &exofs_dir_operations;
inode->i_mapping->a_ops = &exofs_aops;
} else if (S_ISLNK(inode->i_mode)) {
if (exofs_inode_is_fast_symlink(inode))
inode->i_op = &exofs_fast_symlink_inode_operations;
else {
inode->i_op = &exofs_symlink_inode_operations;
inode->i_mapping->a_ops = &exofs_aops;
}
} else {
inode->i_op = &exofs_special_inode_operations;
if (fcb.i_data[0])
init_special_inode(inode, inode->i_mode,
old_decode_dev(le32_to_cpu(fcb.i_data[0])));
else
init_special_inode(inode, inode->i_mode,
new_decode_dev(le32_to_cpu(fcb.i_data[1])));
}
unlock_new_inode(inode);
return inode;
bad_inode:
iget_failed(inode);
return ERR_PTR(ret);
}
int __exofs_wait_obj_created(struct exofs_i_info *oi)
{
if (!obj_created(oi)) {
BUG_ON(!obj_2bcreated(oi));
wait_event(oi->i_wq, obj_created(oi));
}
return unlikely(is_bad_inode(&oi->vfs_inode)) ? -EIO : 0;
}
/*
* Callback function from exofs_new_inode(). The important thing is that we
* set the obj_created flag so that other methods know that the object exists on
* the OSD.
*/
static void create_done(struct osd_request *or, void *p)
{
struct inode *inode = p;
struct exofs_i_info *oi = exofs_i(inode);
struct exofs_sb_info *sbi = inode->i_sb->s_fs_info;
int ret;
ret = exofs_check_ok(or);
osd_end_request(or);
atomic_dec(&sbi->s_curr_pending);
if (unlikely(ret)) {
EXOFS_ERR("object=0x%llx creation faild in pid=0x%llx",
_LLU(sbi->s_pid), _LLU(inode->i_ino + EXOFS_OBJ_OFF));
make_bad_inode(inode);
} else
set_obj_created(oi);
atomic_dec(&inode->i_count);
wake_up(&oi->i_wq);
}
/*
* Set up a new inode and create an object for it on the OSD
*/
struct inode *exofs_new_inode(struct inode *dir, int mode)
{
struct super_block *sb;
struct inode *inode;
struct exofs_i_info *oi;
struct exofs_sb_info *sbi;
struct osd_request *or;
struct osd_obj_id obj;
int ret;
sb = dir->i_sb;
inode = new_inode(sb);
if (!inode)
return ERR_PTR(-ENOMEM);
oi = exofs_i(inode);
init_waitqueue_head(&oi->i_wq);
set_obj_2bcreated(oi);
sbi = sb->s_fs_info;
sb->s_dirt = 1;
inode->i_uid = current->cred->fsuid;
if (dir->i_mode & S_ISGID) {
inode->i_gid = dir->i_gid;
if (S_ISDIR(mode))
mode |= S_ISGID;
} else {
inode->i_gid = current->cred->fsgid;
}
inode->i_mode = mode;
inode->i_ino = sbi->s_nextid++;
inode->i_blkbits = EXOFS_BLKSHIFT;
inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
oi->i_commit_size = inode->i_size = 0;
spin_lock(&sbi->s_next_gen_lock);
inode->i_generation = sbi->s_next_generation++;
spin_unlock(&sbi->s_next_gen_lock);
insert_inode_hash(inode);
mark_inode_dirty(inode);
obj.partition = sbi->s_pid;
obj.id = inode->i_ino + EXOFS_OBJ_OFF;
exofs_make_credential(oi->i_cred, &obj);
or = osd_start_request(sbi->s_dev, GFP_KERNEL);
if (unlikely(!or)) {
EXOFS_ERR("exofs_new_inode: osd_start_request failed\n");
return ERR_PTR(-ENOMEM);
}
osd_req_create_object(or, &obj);
/* increment the refcount so that the inode will still be around when we
* reach the callback
*/
atomic_inc(&inode->i_count);
ret = exofs_async_op(or, create_done, inode, oi->i_cred);
if (ret) {
atomic_dec(&inode->i_count);
osd_end_request(or);
return ERR_PTR(-EIO);
}
atomic_inc(&sbi->s_curr_pending);
return inode;
}

342
fs/exofs/namei.c Normal file
View File

@ -0,0 +1,342 @@
/*
* Copyright (C) 2005, 2006
* Avishay Traeger (avishay@gmail.com) (avishay@il.ibm.com)
* Copyright (C) 2005, 2006
* International Business Machines
* Copyright (C) 2008, 2009
* Boaz Harrosh <bharrosh@panasas.com>
*
* Copyrights for code taken from ext2:
* Copyright (C) 1992, 1993, 1994, 1995
* Remy Card (card@masi.ibp.fr)
* Laboratoire MASI - Institut Blaise Pascal
* Universite Pierre et Marie Curie (Paris VI)
* from
* linux/fs/minix/inode.c
* Copyright (C) 1991, 1992 Linus Torvalds
*
* This file is part of exofs.
*
* exofs 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. Since it is based on ext2, and the only
* valid version of GPL for the Linux kernel is version 2, the only valid
* version of GPL for exofs is version 2.
*
* exofs 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 exofs; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "exofs.h"
static inline int exofs_add_nondir(struct dentry *dentry, struct inode *inode)
{
int err = exofs_add_link(dentry, inode);
if (!err) {
d_instantiate(dentry, inode);
return 0;
}
inode_dec_link_count(inode);
iput(inode);
return err;
}
static struct dentry *exofs_lookup(struct inode *dir, struct dentry *dentry,
struct nameidata *nd)
{
struct inode *inode;
ino_t ino;
if (dentry->d_name.len > EXOFS_NAME_LEN)
return ERR_PTR(-ENAMETOOLONG);
ino = exofs_inode_by_name(dir, dentry);
inode = NULL;
if (ino) {
inode = exofs_iget(dir->i_sb, ino);
if (IS_ERR(inode))
return ERR_CAST(inode);
}
return d_splice_alias(inode, dentry);
}
static int exofs_create(struct inode *dir, struct dentry *dentry, int mode,
struct nameidata *nd)
{
struct inode *inode = exofs_new_inode(dir, mode);
int err = PTR_ERR(inode);
if (!IS_ERR(inode)) {
inode->i_op = &exofs_file_inode_operations;
inode->i_fop = &exofs_file_operations;
inode->i_mapping->a_ops = &exofs_aops;
mark_inode_dirty(inode);
err = exofs_add_nondir(dentry, inode);
}
return err;
}
static int exofs_mknod(struct inode *dir, struct dentry *dentry, int mode,
dev_t rdev)
{
struct inode *inode;
int err;
if (!new_valid_dev(rdev))
return -EINVAL;
inode = exofs_new_inode(dir, mode);
err = PTR_ERR(inode);
if (!IS_ERR(inode)) {
init_special_inode(inode, inode->i_mode, rdev);
mark_inode_dirty(inode);
err = exofs_add_nondir(dentry, inode);
}
return err;
}
static int exofs_symlink(struct inode *dir, struct dentry *dentry,
const char *symname)
{
struct super_block *sb = dir->i_sb;
int err = -ENAMETOOLONG;
unsigned l = strlen(symname)+1;
struct inode *inode;
struct exofs_i_info *oi;
if (l > sb->s_blocksize)
goto out;
inode = exofs_new_inode(dir, S_IFLNK | S_IRWXUGO);
err = PTR_ERR(inode);
if (IS_ERR(inode))
goto out;
oi = exofs_i(inode);
if (l > sizeof(oi->i_data)) {
/* slow symlink */
inode->i_op = &exofs_symlink_inode_operations;
inode->i_mapping->a_ops = &exofs_aops;
memset(oi->i_data, 0, sizeof(oi->i_data));
err = page_symlink(inode, symname, l);
if (err)
goto out_fail;
} else {
/* fast symlink */
inode->i_op = &exofs_fast_symlink_inode_operations;
memcpy(oi->i_data, symname, l);
inode->i_size = l-1;
}
mark_inode_dirty(inode);
err = exofs_add_nondir(dentry, inode);
out:
return err;
out_fail:
inode_dec_link_count(inode);
iput(inode);
goto out;
}
static int exofs_link(struct dentry *old_dentry, struct inode *dir,
struct dentry *dentry)
{
struct inode *inode = old_dentry->d_inode;
if (inode->i_nlink >= EXOFS_LINK_MAX)
return -EMLINK;
inode->i_ctime = CURRENT_TIME;
inode_inc_link_count(inode);
atomic_inc(&inode->i_count);
return exofs_add_nondir(dentry, inode);
}
static int exofs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
{
struct inode *inode;
int err = -EMLINK;
if (dir->i_nlink >= EXOFS_LINK_MAX)
goto out;
inode_inc_link_count(dir);
inode = exofs_new_inode(dir, S_IFDIR | mode);
err = PTR_ERR(inode);
if (IS_ERR(inode))
goto out_dir;
inode->i_op = &exofs_dir_inode_operations;
inode->i_fop = &exofs_dir_operations;
inode->i_mapping->a_ops = &exofs_aops;
inode_inc_link_count(inode);
err = exofs_make_empty(inode, dir);
if (err)
goto out_fail;
err = exofs_add_link(dentry, inode);
if (err)
goto out_fail;
d_instantiate(dentry, inode);
out:
return err;
out_fail:
inode_dec_link_count(inode);
inode_dec_link_count(inode);
iput(inode);
out_dir:
inode_dec_link_count(dir);
goto out;
}
static int exofs_unlink(struct inode *dir, struct dentry *dentry)
{
struct inode *inode = dentry->d_inode;
struct exofs_dir_entry *de;
struct page *page;
int err = -ENOENT;
de = exofs_find_entry(dir, dentry, &page);
if (!de)
goto out;
err = exofs_delete_entry(de, page);
if (err)
goto out;
inode->i_ctime = dir->i_ctime;
inode_dec_link_count(inode);
err = 0;
out:
return err;
}
static int exofs_rmdir(struct inode *dir, struct dentry *dentry)
{
struct inode *inode = dentry->d_inode;
int err = -ENOTEMPTY;
if (exofs_empty_dir(inode)) {
err = exofs_unlink(dir, dentry);
if (!err) {
inode->i_size = 0;
inode_dec_link_count(inode);
inode_dec_link_count(dir);
}
}
return err;
}
static int exofs_rename(struct inode *old_dir, struct dentry *old_dentry,
struct inode *new_dir, struct dentry *new_dentry)
{
struct inode *old_inode = old_dentry->d_inode;
struct inode *new_inode = new_dentry->d_inode;
struct page *dir_page = NULL;
struct exofs_dir_entry *dir_de = NULL;
struct page *old_page;
struct exofs_dir_entry *old_de;
int err = -ENOENT;
old_de = exofs_find_entry(old_dir, old_dentry, &old_page);
if (!old_de)
goto out;
if (S_ISDIR(old_inode->i_mode)) {
err = -EIO;
dir_de = exofs_dotdot(old_inode, &dir_page);
if (!dir_de)
goto out_old;
}
if (new_inode) {
struct page *new_page;
struct exofs_dir_entry *new_de;
err = -ENOTEMPTY;
if (dir_de && !exofs_empty_dir(new_inode))
goto out_dir;
err = -ENOENT;
new_de = exofs_find_entry(new_dir, new_dentry, &new_page);
if (!new_de)
goto out_dir;
inode_inc_link_count(old_inode);
err = exofs_set_link(new_dir, new_de, new_page, old_inode);
new_inode->i_ctime = CURRENT_TIME;
if (dir_de)
drop_nlink(new_inode);
inode_dec_link_count(new_inode);
if (err)
goto out_dir;
} else {
if (dir_de) {
err = -EMLINK;
if (new_dir->i_nlink >= EXOFS_LINK_MAX)
goto out_dir;
}
inode_inc_link_count(old_inode);
err = exofs_add_link(new_dentry, old_inode);
if (err) {
inode_dec_link_count(old_inode);
goto out_dir;
}
if (dir_de)
inode_inc_link_count(new_dir);
}
old_inode->i_ctime = CURRENT_TIME;
exofs_delete_entry(old_de, old_page);
inode_dec_link_count(old_inode);
if (dir_de) {
err = exofs_set_link(old_inode, dir_de, dir_page, new_dir);
inode_dec_link_count(old_dir);
if (err)
goto out_dir;
}
return 0;
out_dir:
if (dir_de) {
kunmap(dir_page);
page_cache_release(dir_page);
}
out_old:
kunmap(old_page);
page_cache_release(old_page);
out:
return err;
}
const struct inode_operations exofs_dir_inode_operations = {
.create = exofs_create,
.lookup = exofs_lookup,
.link = exofs_link,
.unlink = exofs_unlink,
.symlink = exofs_symlink,
.mkdir = exofs_mkdir,
.rmdir = exofs_rmdir,
.mknod = exofs_mknod,
.rename = exofs_rename,
.setattr = exofs_setattr,
};
const struct inode_operations exofs_special_inode_operations = {
.setattr = exofs_setattr,
};