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afs: Locally edit directory data for mkdir/create/unlink/...

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Locally edit the contents of an AFS directory upon a successful inode
operation that modifies that directory (such as mkdir, create and unlink)
so that we can avoid the current practice of re-downloading the directory
after each change.

This is viable provided that the directory version number we get back from
the modifying RPC op is exactly incremented by 1 from what we had
previously.  The data in the directory contents is in a defined format that
we have to parse locally to perform lookups and readdir, so modifying isn't
a problem.

If the edit fails, we just clear the VALID flag on the directory and it
will be reloaded next time it is needed.

Signed-off-by: David Howells <dhowells@redhat.com>
This commit is contained in:
David Howells 2018-04-06 14:17:25 +01:00
parent 0031763698
commit 63a4681ff3
8 changed files with 715 additions and 29 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

1
fs/afs/Makefile
View file

@ -12,6 +12,7 @@ kafs-objs := \
cell.o \
cmservice.o \
dir.o \
dir_edit.o \
dynroot.o \
file.o \
flock.o \

83
fs/afs/dir.c
View file

@ -130,17 +130,26 @@ static bool afs_dir_check_page(struct afs_vnode *dvnode, struct page *page,
qty /= sizeof(union afs_xdr_dir_block);
/* check them */
dbuf = page_address(page);
dbuf = kmap(page);
for (tmp = 0; tmp < qty; tmp++) {
if (dbuf->blocks[tmp].hdr.magic != AFS_DIR_MAGIC) {
printk("kAFS: %s(%lx): bad magic %d/%d is %04hx\n",
__func__, dvnode->vfs_inode.i_ino, tmp, qty,
ntohs(dbuf->blocks[tmp].hdr.magic));
trace_afs_dir_check_failed(dvnode, off, i_size);
kunmap(page);
goto error;
}
/* Make sure each block is NUL terminated so we can reasonably
* use string functions on it. The filenames in the page
* *should* be NUL-terminated anyway.
*/
((u8 *)&dbuf->blocks[tmp])[AFS_DIR_BLOCK_SIZE - 1] = 0;
}
kunmap(page);
checked:
afs_stat_v(dvnode, n_read_dir);
return true;
@ -1114,6 +1123,7 @@ static int afs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
struct afs_vnode *dvnode = AFS_FS_I(dir);
struct afs_fid newfid;
struct key *key;
u64 data_version = dvnode->status.data_version;
int ret;
mode |= S_IFDIR;
@ -1131,7 +1141,7 @@ static int afs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
if (afs_begin_vnode_operation(&fc, dvnode, key)) {
while (afs_select_fileserver(&fc)) {
fc.cb_break = dvnode->cb_break + dvnode->cb_s_break;
afs_fs_create(&fc, dentry->d_name.name, mode,
afs_fs_create(&fc, dentry->d_name.name, mode, data_version,
&newfid, &newstatus, &newcb);
}
@ -1145,6 +1155,11 @@ static int afs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
goto error_key;
}
if (ret == 0 &&
test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
afs_edit_dir_add(dvnode, &dentry->d_name, &newfid,
afs_edit_dir_for_create);
key_put(key);
_leave(" = 0");
return 0;
@ -1168,6 +1183,7 @@ static void afs_dir_remove_subdir(struct dentry *dentry)
clear_nlink(&vnode->vfs_inode);
set_bit(AFS_VNODE_DELETED, &vnode->flags);
clear_bit(AFS_VNODE_CB_PROMISED, &vnode->flags);
clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags);
}
}
@ -1179,6 +1195,7 @@ static int afs_rmdir(struct inode *dir, struct dentry *dentry)
struct afs_fs_cursor fc;
struct afs_vnode *dvnode = AFS_FS_I(dir);
struct key *key;
u64 data_version = dvnode->status.data_version;
int ret;
_enter("{%x:%u},{%pd}",
@ -1194,13 +1211,18 @@ static int afs_rmdir(struct inode *dir, struct dentry *dentry)
if (afs_begin_vnode_operation(&fc, dvnode, key)) {
while (afs_select_fileserver(&fc)) {
fc.cb_break = dvnode->cb_break + dvnode->cb_s_break;
afs_fs_remove(&fc, dentry->d_name.name, true);
afs_fs_remove(&fc, dentry->d_name.name, true,
data_version);
}
afs_vnode_commit_status(&fc, dvnode, fc.cb_break);
ret = afs_end_vnode_operation(&fc);
if (ret == 0)
if (ret == 0) {
afs_dir_remove_subdir(dentry);
if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
afs_edit_dir_remove(dvnode, &dentry->d_name,
afs_edit_dir_for_rmdir);
}
}
key_put(key);
@ -1265,6 +1287,7 @@ static int afs_unlink(struct inode *dir, struct dentry *dentry)
struct afs_vnode *dvnode = AFS_FS_I(dir), *vnode;
struct key *key;
unsigned long d_version = (unsigned long)dentry->d_fsdata;
u64 data_version = dvnode->status.data_version;
int ret;
_enter("{%x:%u},{%pd}",
@ -1291,7 +1314,8 @@ static int afs_unlink(struct inode *dir, struct dentry *dentry)
if (afs_begin_vnode_operation(&fc, dvnode, key)) {
while (afs_select_fileserver(&fc)) {
fc.cb_break = dvnode->cb_break + dvnode->cb_s_break;
afs_fs_remove(&fc, dentry->d_name.name, false);
afs_fs_remove(&fc, dentry->d_name.name, false,
data_version);
}
afs_vnode_commit_status(&fc, dvnode, fc.cb_break);
@ -1300,6 +1324,10 @@ static int afs_unlink(struct inode *dir, struct dentry *dentry)
ret = afs_dir_remove_link(
dentry, key, d_version,
(unsigned long)dvnode->status.data_version);
if (ret == 0 &&
test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
afs_edit_dir_remove(dvnode, &dentry->d_name,
afs_edit_dir_for_unlink);
}
error_key:
@ -1321,6 +1349,7 @@ static int afs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
struct afs_vnode *dvnode = AFS_FS_I(dir);
struct afs_fid newfid;
struct key *key;
u64 data_version = dvnode->status.data_version;
int ret;
mode |= S_IFREG;
@ -1342,7 +1371,7 @@ static int afs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
if (afs_begin_vnode_operation(&fc, dvnode, key)) {
while (afs_select_fileserver(&fc)) {
fc.cb_break = dvnode->cb_break + dvnode->cb_s_break;
afs_fs_create(&fc, dentry->d_name.name, mode,
afs_fs_create(&fc, dentry->d_name.name, mode, data_version,
&newfid, &newstatus, &newcb);
}
@ -1356,6 +1385,10 @@ static int afs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
goto error_key;
}
if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
afs_edit_dir_add(dvnode, &dentry->d_name, &newfid,
afs_edit_dir_for_create);
key_put(key);
_leave(" = 0");
return 0;
@ -1377,10 +1410,12 @@ static int afs_link(struct dentry *from, struct inode *dir,
struct afs_fs_cursor fc;
struct afs_vnode *dvnode, *vnode;
struct key *key;
u64 data_version;
int ret;
vnode = AFS_FS_I(d_inode(from));
dvnode = AFS_FS_I(dir);
data_version = dvnode->status.data_version;
_enter("{%x:%u},{%x:%u},{%pd}",
vnode->fid.vid, vnode->fid.vnode,
@ -1407,7 +1442,7 @@ static int afs_link(struct dentry *from, struct inode *dir,
while (afs_select_fileserver(&fc)) {
fc.cb_break = dvnode->cb_break + dvnode->cb_s_break;
fc.cb_break_2 = vnode->cb_break + vnode->cb_s_break;
afs_fs_link(&fc, vnode, dentry->d_name.name);
afs_fs_link(&fc, vnode, dentry->d_name.name, data_version);
}
afs_vnode_commit_status(&fc, dvnode, fc.cb_break);
@ -1423,6 +1458,10 @@ static int afs_link(struct dentry *from, struct inode *dir,
goto error_key;
}
if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
afs_edit_dir_add(dvnode, &dentry->d_name, &vnode->fid,
afs_edit_dir_for_link);
key_put(key);
_leave(" = 0");
return 0;
@ -1446,6 +1485,7 @@ static int afs_symlink(struct inode *dir, struct dentry *dentry,
struct afs_vnode *dvnode = AFS_FS_I(dir);
struct afs_fid newfid;
struct key *key;
u64 data_version = dvnode->status.data_version;
int ret;
_enter("{%x:%u},{%pd},%s",
@ -1470,7 +1510,8 @@ static int afs_symlink(struct inode *dir, struct dentry *dentry,
if (afs_begin_vnode_operation(&fc, dvnode, key)) {
while (afs_select_fileserver(&fc)) {
fc.cb_break = dvnode->cb_break + dvnode->cb_s_break;
afs_fs_symlink(&fc, dentry->d_name.name, content,
afs_fs_symlink(&fc, dentry->d_name.name,
content, data_version,
&newfid, &newstatus);
}
@ -1484,6 +1525,10 @@ static int afs_symlink(struct inode *dir, struct dentry *dentry,
goto error_key;
}
if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
afs_edit_dir_add(dvnode, &dentry->d_name, &newfid,
afs_edit_dir_for_symlink);
key_put(key);
_leave(" = 0");
return 0;
@ -1506,6 +1551,8 @@ static int afs_rename(struct inode *old_dir, struct dentry *old_dentry,
struct afs_fs_cursor fc;
struct afs_vnode *orig_dvnode, *new_dvnode, *vnode;
struct key *key;
u64 orig_data_version, new_data_version;
bool new_negative = d_is_negative(new_dentry);
int ret;
if (flags)
@ -1514,6 +1561,8 @@ static int afs_rename(struct inode *old_dir, struct dentry *old_dentry,
vnode = AFS_FS_I(d_inode(old_dentry));
orig_dvnode = AFS_FS_I(old_dir);
new_dvnode = AFS_FS_I(new_dir);
orig_data_version = orig_dvnode->status.data_version;
new_data_version = new_dvnode->status.data_version;
_enter("{%x:%u},{%x:%u},{%x:%u},{%pd}",
orig_dvnode->fid.vid, orig_dvnode->fid.vnode,
@ -1539,7 +1588,8 @@ static int afs_rename(struct inode *old_dir, struct dentry *old_dentry,
fc.cb_break = orig_dvnode->cb_break + orig_dvnode->cb_s_break;
fc.cb_break_2 = new_dvnode->cb_break + new_dvnode->cb_s_break;
afs_fs_rename(&fc, old_dentry->d_name.name,
new_dvnode, new_dentry->d_name.name);
new_dvnode, new_dentry->d_name.name,
orig_data_version, new_data_version);
}
afs_vnode_commit_status(&fc, orig_dvnode, fc.cb_break);
@ -1551,6 +1601,21 @@ static int afs_rename(struct inode *old_dir, struct dentry *old_dentry,
goto error_key;
}
if (ret == 0) {
if (test_bit(AFS_VNODE_DIR_VALID, &orig_dvnode->flags))
afs_edit_dir_remove(orig_dvnode, &old_dentry->d_name,
afs_edit_dir_for_rename);
if (!new_negative &&
test_bit(AFS_VNODE_DIR_VALID, &new_dvnode->flags))
afs_edit_dir_remove(new_dvnode, &new_dentry->d_name,
afs_edit_dir_for_rename);
if (test_bit(AFS_VNODE_DIR_VALID, &new_dvnode->flags))
afs_edit_dir_add(new_dvnode, &new_dentry->d_name,
&vnode->fid, afs_edit_dir_for_rename);
}
error_key:
key_put(key);
error:

505
fs/afs/dir_edit.c Normal file
View file

@ -0,0 +1,505 @@
/* AFS filesystem directory editing
*
* Copyright (C) 2018 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public Licence
* as published by the Free Software Foundation; either version
* 2 of the Licence, or (at your option) any later version.
*/
#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/namei.h>
#include <linux/pagemap.h>
#include <linux/iversion.h>
#include "internal.h"
#include "xdr_fs.h"
/*
* Find a number of contiguous clear bits in a directory block bitmask.
*
* There are 64 slots, which means we can load the entire bitmap into a
* variable. The first bit doesn't count as it corresponds to the block header
* slot. nr_slots is between 1 and 9.
*/
static int afs_find_contig_bits(union afs_xdr_dir_block *block, unsigned int nr_slots)
{
u64 bitmap;
u32 mask;
int bit, n;
bitmap = (u64)block->hdr.bitmap[0] << 0 * 8;
bitmap |= (u64)block->hdr.bitmap[1] << 1 * 8;
bitmap |= (u64)block->hdr.bitmap[2] << 2 * 8;
bitmap |= (u64)block->hdr.bitmap[3] << 3 * 8;
bitmap |= (u64)block->hdr.bitmap[4] << 4 * 8;
bitmap |= (u64)block->hdr.bitmap[5] << 5 * 8;
bitmap |= (u64)block->hdr.bitmap[6] << 6 * 8;
bitmap |= (u64)block->hdr.bitmap[7] << 7 * 8;
bitmap >>= 1; /* The first entry is metadata */
bit = 1;
mask = (1 << nr_slots) - 1;
do {
if (sizeof(unsigned long) == 8)
n = ffz(bitmap);
else
n = ((u32)bitmap) != 0 ?
ffz((u32)bitmap) :
ffz((u32)(bitmap >> 32)) + 32;
bitmap >>= n;
bit += n;
if ((bitmap & mask) == 0) {
if (bit > 64 - nr_slots)
return -1;
return bit;
}
n = __ffs(bitmap);
bitmap >>= n;
bit += n;
} while (bitmap);
return -1;
}
/*
* Set a number of contiguous bits in the directory block bitmap.
*/
static void afs_set_contig_bits(union afs_xdr_dir_block *block,
int bit, unsigned int nr_slots)
{
u64 mask, before, after;
mask = (1 << nr_slots) - 1;
mask <<= bit;
before = *(u64 *)block->hdr.bitmap;
block->hdr.bitmap[0] |= (u8)(mask >> 0 * 8);
block->hdr.bitmap[1] |= (u8)(mask >> 1 * 8);
block->hdr.bitmap[2] |= (u8)(mask >> 2 * 8);
block->hdr.bitmap[3] |= (u8)(mask >> 3 * 8);
block->hdr.bitmap[4] |= (u8)(mask >> 4 * 8);
block->hdr.bitmap[5] |= (u8)(mask >> 5 * 8);
block->hdr.bitmap[6] |= (u8)(mask >> 6 * 8);
block->hdr.bitmap[7] |= (u8)(mask >> 7 * 8);
after = *(u64 *)block->hdr.bitmap;
}
/*
* Clear a number of contiguous bits in the directory block bitmap.
*/
static void afs_clear_contig_bits(union afs_xdr_dir_block *block,
int bit, unsigned int nr_slots)
{
u64 mask, before, after;
mask = (1 << nr_slots) - 1;
mask <<= bit;
before = *(u64 *)block->hdr.bitmap;
block->hdr.bitmap[0] &= ~(u8)(mask >> 0 * 8);
block->hdr.bitmap[1] &= ~(u8)(mask >> 1 * 8);
block->hdr.bitmap[2] &= ~(u8)(mask >> 2 * 8);
block->hdr.bitmap[3] &= ~(u8)(mask >> 3 * 8);
block->hdr.bitmap[4] &= ~(u8)(mask >> 4 * 8);
block->hdr.bitmap[5] &= ~(u8)(mask >> 5 * 8);
block->hdr.bitmap[6] &= ~(u8)(mask >> 6 * 8);
block->hdr.bitmap[7] &= ~(u8)(mask >> 7 * 8);
after = *(u64 *)block->hdr.bitmap;
}
/*
* Scan a directory block looking for a dirent of the right name.
*/
static int afs_dir_scan_block(union afs_xdr_dir_block *block, struct qstr *name,
unsigned int blocknum)
{
union afs_xdr_dirent *de;
u64 bitmap;
int d, len, n;
_enter("");
bitmap = (u64)block->hdr.bitmap[0] << 0 * 8;
bitmap |= (u64)block->hdr.bitmap[1] << 1 * 8;
bitmap |= (u64)block->hdr.bitmap[2] << 2 * 8;
bitmap |= (u64)block->hdr.bitmap[3] << 3 * 8;
bitmap |= (u64)block->hdr.bitmap[4] << 4 * 8;
bitmap |= (u64)block->hdr.bitmap[5] << 5 * 8;
bitmap |= (u64)block->hdr.bitmap[6] << 6 * 8;
bitmap |= (u64)block->hdr.bitmap[7] << 7 * 8;
for (d = (blocknum == 0 ? AFS_DIR_RESV_BLOCKS0 : AFS_DIR_RESV_BLOCKS);
d < AFS_DIR_SLOTS_PER_BLOCK;
d++) {
if (!((bitmap >> d) & 1))
continue;
de = &block->dirents[d];
if (de->u.valid != 1)
continue;
/* The block was NUL-terminated by afs_dir_check_page(). */
len = strlen(de->u.name);
if (len == name->len &&
memcmp(de->u.name, name->name, name->len) == 0)
return d;
n = round_up(12 + len + 1 + 4, AFS_DIR_DIRENT_SIZE);
n /= AFS_DIR_DIRENT_SIZE;
d += n - 1;
}
return -1;
}
/*
* Initialise a new directory block. Note that block 0 is special and contains
* some extra metadata.
*/
static void afs_edit_init_block(union afs_xdr_dir_block *meta,
union afs_xdr_dir_block *block, int block_num)
{
memset(block, 0, sizeof(*block));
block->hdr.npages = htons(1);
block->hdr.magic = AFS_DIR_MAGIC;
block->hdr.bitmap[0] = 1;
if (block_num == 0) {
block->hdr.bitmap[0] = 0xff;
block->hdr.bitmap[1] = 0x1f;
memset(block->meta.alloc_ctrs,
AFS_DIR_SLOTS_PER_BLOCK,
sizeof(block->meta.alloc_ctrs));
meta->meta.alloc_ctrs[0] =
AFS_DIR_SLOTS_PER_BLOCK - AFS_DIR_RESV_BLOCKS0;
}
if (block_num < AFS_DIR_BLOCKS_WITH_CTR)
meta->meta.alloc_ctrs[block_num] =
AFS_DIR_SLOTS_PER_BLOCK - AFS_DIR_RESV_BLOCKS;
}
/*
* Edit a directory's file data to add a new directory entry. Doing this after
* create, mkdir, symlink, link or rename if the data version number is
* incremented by exactly one avoids the need to re-download the entire
* directory contents.
*
* The caller must hold the inode locked.
*/
void afs_edit_dir_add(struct afs_vnode *vnode,
struct qstr *name, struct afs_fid *new_fid,
enum afs_edit_dir_reason why)
{
union afs_xdr_dir_block *meta, *block;
struct afs_xdr_dir_page *meta_page, *dir_page;
union afs_xdr_dirent *de;
struct page *page0, *page;
unsigned int need_slots, nr_blocks, b;
pgoff_t index;
loff_t i_size;
gfp_t gfp;
int slot;
_enter(",,{%d,%s},", name->len, name->name);
i_size = i_size_read(&vnode->vfs_inode);
if (i_size > AFS_DIR_BLOCK_SIZE * AFS_DIR_MAX_BLOCKS ||
(i_size & (AFS_DIR_BLOCK_SIZE - 1))) {
clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags);
return;
}
gfp = vnode->vfs_inode.i_mapping->gfp_mask;
page0 = find_or_create_page(vnode->vfs_inode.i_mapping, 0, gfp);
if (!page0) {
clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags);
_leave(" [fgp]");
return;
}
/* Work out how many slots we're going to need. */
need_slots = round_up(12 + name->len + 1 + 4, AFS_DIR_DIRENT_SIZE);
need_slots /= AFS_DIR_DIRENT_SIZE;
meta_page = kmap(page0);
meta = &meta_page->blocks[0];
if (i_size == 0)
goto new_directory;
nr_blocks = i_size / AFS_DIR_BLOCK_SIZE;
/* Find a block that has sufficient slots available. Each VM page
* contains two or more directory blocks.
*/
for (b = 0; b < nr_blocks + 1; b++) {
/* If the directory extended into a new page, then we need to
* tack a new page on the end.
*/
index = b / AFS_DIR_BLOCKS_PER_PAGE;
if (index == 0) {
page = page0;
dir_page = meta_page;
} else {
if (nr_blocks >= AFS_DIR_MAX_BLOCKS)
goto error;
gfp = vnode->vfs_inode.i_mapping->gfp_mask;
page = find_or_create_page(vnode->vfs_inode.i_mapping,
index, gfp);
if (!page)
goto error;
if (!PagePrivate(page)) {
set_page_private(page, 1);
SetPagePrivate(page);
}
dir_page = kmap(page);
}
/* Abandon the edit if we got a callback break. */
if (!test_bit(AFS_VNODE_DIR_VALID, &vnode->flags))
goto invalidated;
block = &dir_page->blocks[b % AFS_DIR_BLOCKS_PER_PAGE];
_debug("block %u: %2u %3u %u",
b,
(b < AFS_DIR_BLOCKS_WITH_CTR) ? meta->meta.alloc_ctrs[b] : 99,
ntohs(block->hdr.npages),
ntohs(block->hdr.magic));
/* Initialise the block if necessary. */
if (b == nr_blocks) {
_debug("init %u", b);
afs_edit_init_block(meta, block, b);
i_size_write(&vnode->vfs_inode, (b + 1) * AFS_DIR_BLOCK_SIZE);
}
/* Only lower dir pages have a counter in the header. */
if (b >= AFS_DIR_BLOCKS_WITH_CTR ||
meta->meta.alloc_ctrs[b] >= need_slots) {
/* We need to try and find one or more consecutive
* slots to hold the entry.
*/
slot = afs_find_contig_bits(block, need_slots);
if (slot >= 0) {
_debug("slot %u", slot);
goto found_space;
}
}
if (page != page0) {
unlock_page(page);
kunmap(page);
put_page(page);
}
}
/* There are no spare slots of sufficient size, yet the operation
* succeeded. Download the directory again.
*/
trace_afs_edit_dir(vnode, why, afs_edit_dir_create_nospc, 0, 0, 0, 0, name->name);
clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags);
goto out_unmap;
new_directory:
afs_edit_init_block(meta, meta, 0);
i_size = AFS_DIR_BLOCK_SIZE;
i_size_write(&vnode->vfs_inode, i_size);
slot = AFS_DIR_RESV_BLOCKS0;
page = page0;
block = meta;
nr_blocks = 1;
b = 0;
found_space:
/* Set the dirent slot. */
trace_afs_edit_dir(vnode, why, afs_edit_dir_create, b, slot,
new_fid->vnode, new_fid->unique, name->name);
de = &block->dirents[slot];
de->u.valid = 1;
de->u.unused[0] = 0;
de->u.hash_next = 0; // TODO: Really need to maintain this
de->u.vnode = htonl(new_fid->vnode);
de->u.unique = htonl(new_fid->unique);
memcpy(de->u.name, name->name, name->len + 1);
de->u.name[name->len] = 0;
/* Adjust the bitmap. */
afs_set_contig_bits(block, slot, need_slots);
if (page != page0) {
unlock_page(page);
kunmap(page);
put_page(page);
}
/* Adjust the allocation counter. */
if (b < AFS_DIR_BLOCKS_WITH_CTR)
meta->meta.alloc_ctrs[b] -= need_slots;
inode_inc_iversion_raw(&vnode->vfs_inode);
afs_stat_v(vnode, n_dir_cr);
_debug("Insert %s in %u[%u]", name->name, b, slot);
out_unmap:
unlock_page(page0);
kunmap(page0);
put_page(page0);
_leave("");
return;
invalidated:
trace_afs_edit_dir(vnode, why, afs_edit_dir_create_inval, 0, 0, 0, 0, name->name);
clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags);
if (page != page0) {
kunmap(page);
put_page(page);
}
goto out_unmap;
error:
trace_afs_edit_dir(vnode, why, afs_edit_dir_create_error, 0, 0, 0, 0, name->name);
clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags);
goto out_unmap;
}
/*
* Edit a directory's file data to remove a new directory entry. Doing this
* after unlink, rmdir or rename if the data version number is incremented by
* exactly one avoids the need to re-download the entire directory contents.
*
* The caller must hold the inode locked.
*/
void afs_edit_dir_remove(struct afs_vnode *vnode,
struct qstr *name, enum afs_edit_dir_reason why)
{
struct afs_xdr_dir_page *meta_page, *dir_page;
union afs_xdr_dir_block *meta, *block;
union afs_xdr_dirent *de;
struct page *page0, *page;
unsigned int need_slots, nr_blocks, b;
pgoff_t index;
loff_t i_size;
int slot;
_enter(",,{%d,%s},", name->len, name->name);
i_size = i_size_read(&vnode->vfs_inode);
if (i_size < AFS_DIR_BLOCK_SIZE ||
i_size > AFS_DIR_BLOCK_SIZE * AFS_DIR_MAX_BLOCKS ||
(i_size & (AFS_DIR_BLOCK_SIZE - 1))) {
clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags);
return;
}
nr_blocks = i_size / AFS_DIR_BLOCK_SIZE;
page0 = find_lock_page(vnode->vfs_inode.i_mapping, 0);
if (!page0) {
clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags);
_leave(" [fgp]");
return;
}
/* Work out how many slots we're going to discard. */
need_slots = round_up(12 + name->len + 1 + 4, AFS_DIR_DIRENT_SIZE);
need_slots /= AFS_DIR_DIRENT_SIZE;
meta_page = kmap(page0);
meta = &meta_page->blocks[0];
/* Find a page that has sufficient slots available. Each VM page
* contains two or more directory blocks.
*/
for (b = 0; b < nr_blocks; b++) {
index = b / AFS_DIR_BLOCKS_PER_PAGE;
if (index != 0) {
page = find_lock_page(vnode->vfs_inode.i_mapping, index);
if (!page)
goto error;
dir_page = kmap(page);
} else {
page = page0;
dir_page = meta_page;
}
/* Abandon the edit if we got a callback break. */
if (!test_bit(AFS_VNODE_DIR_VALID, &vnode->flags))
goto invalidated;
block = &dir_page->blocks[b % AFS_DIR_BLOCKS_PER_PAGE];
if (b > AFS_DIR_BLOCKS_WITH_CTR ||
meta->meta.alloc_ctrs[b] <= AFS_DIR_SLOTS_PER_BLOCK - 1 - need_slots) {
slot = afs_dir_scan_block(block, name, b);
if (slot >= 0)
goto found_dirent;
}
if (page != page0) {
unlock_page(page);
kunmap(page);
put_page(page);
}
}
/* Didn't find the dirent to clobber. Download the directory again. */
trace_afs_edit_dir(vnode, why, afs_edit_dir_delete_noent,
0, 0, 0, 0, name->name);
clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags);
goto out_unmap;
found_dirent:
de = &block->dirents[slot];
trace_afs_edit_dir(vnode, why, afs_edit_dir_delete, b, slot,
ntohl(de->u.vnode), ntohl(de->u.unique),
name->name);
memset(de, 0, sizeof(*de) * need_slots);
/* Adjust the bitmap. */
afs_clear_contig_bits(block, slot, need_slots);
if (page != page0) {
unlock_page(page);
kunmap(page);
put_page(page);
}
/* Adjust the allocation counter. */
if (b < AFS_DIR_BLOCKS_WITH_CTR)
meta->meta.alloc_ctrs[b] += need_slots;
inode_set_iversion_raw(&vnode->vfs_inode, vnode->status.data_version);
afs_stat_v(vnode, n_dir_rm);
_debug("Remove %s from %u[%u]", name->name, b, slot);
out_unmap:
unlock_page(page0);
kunmap(page0);
put_page(page0);
_leave("");
return;
invalidated:
trace_afs_edit_dir(vnode, why, afs_edit_dir_delete_inval,
0, 0, 0, 0, name->name);
clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags);
if (page != page0) {
unlock_page(page);
kunmap(page);
put_page(page);
}
goto out_unmap;
error:
trace_afs_edit_dir(vnode, why, afs_edit_dir_delete_error,
0, 0, 0, 0, name->name);
clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags);
goto out_unmap;
}

35
fs/afs/fsclient.c
View file

@ -107,6 +107,13 @@ void afs_update_inode_from_status(struct afs_vnode *vnode,
} else {
set_bit(AFS_VNODE_ZAP_DATA, &vnode->flags);
}
} else if (vnode->status.type == AFS_FTYPE_DIR) {
/* Expected directory change is handled elsewhere so
* that we can locally edit the directory and save on a
* download.
*/
if (test_bit(AFS_VNODE_DIR_VALID, &vnode->flags))
flags &= ~AFS_VNODE_DATA_CHANGED;
}
}
@ -190,10 +197,7 @@ static int xdr_decode_AFSFetchStatus(const __be32 **_bp,
size = (u64)ntohl(xdr->size_lo);
size |= (u64)ntohl(xdr->size_hi) << 32;
if (size != status->size) {
status->size = size;
flags |= AFS_VNODE_DATA_CHANGED;
}
status->size = size;
data_version = (u64)ntohl(xdr->data_version_lo);
data_version |= (u64)ntohl(xdr->data_version_hi) << 32;
@ -736,6 +740,7 @@ static const struct afs_call_type afs_RXFSMakeDir = {
int afs_fs_create(struct afs_fs_cursor *fc,
const char *name,
umode_t mode,
u64 current_data_version,
struct afs_fid *newfid,
struct afs_file_status *newstatus,
struct afs_callback *newcb)
@ -763,7 +768,7 @@ int afs_fs_create(struct afs_fs_cursor *fc,
call->reply[1] = newfid;
call->reply[2] = newstatus;
call->reply[3] = newcb;
call->expected_version = vnode->status.data_version;
call->expected_version = current_data_version + 1;
/* marshall the parameters */
bp = call->request;
@ -836,7 +841,8 @@ static const struct afs_call_type afs_RXFSRemoveDir = {
/*
* remove a file or directory
*/
int afs_fs_remove(struct afs_fs_cursor *fc, const char *name, bool isdir)
int afs_fs_remove(struct afs_fs_cursor *fc, const char *name, bool isdir,
u64 current_data_version)
{
struct afs_vnode *vnode = fc->vnode;
struct afs_call *call;
@ -858,7 +864,7 @@ int afs_fs_remove(struct afs_fs_cursor *fc, const char *name, bool isdir)
call->key = fc->key;
call->reply[0] = vnode;
call->expected_version = vnode->status.data_version;
call->expected_version = current_data_version + 1;
/* marshall the parameters */
bp = call->request;
@ -920,7 +926,7 @@ static const struct afs_call_type afs_RXFSLink = {
* make a hard link
*/
int afs_fs_link(struct afs_fs_cursor *fc, struct afs_vnode *vnode,
const char *name)
const char *name, u64 current_data_version)
{
struct afs_vnode *dvnode = fc->vnode;
struct afs_call *call;
@ -941,7 +947,7 @@ int afs_fs_link(struct afs_fs_cursor *fc, struct afs_vnode *vnode,
call->key = fc->key;
call->reply[0] = dvnode;
call->reply[1] = vnode;
call->expected_version = vnode->status.data_version;
call->expected_version = current_data_version + 1;
/* marshall the parameters */
bp = call->request;
@ -1009,6 +1015,7 @@ static const struct afs_call_type afs_RXFSSymlink = {
int afs_fs_symlink(struct afs_fs_cursor *fc,
const char *name,
const char *contents,
u64 current_data_version,
struct afs_fid *newfid,
struct afs_file_status *newstatus)
{
@ -1037,7 +1044,7 @@ int afs_fs_symlink(struct afs_fs_cursor *fc,
call->reply[0] = vnode;
call->reply[1] = newfid;
call->reply[2] = newstatus;
call->expected_version = vnode->status.data_version;
call->expected_version = current_data_version + 1;
/* marshall the parameters */
bp = call->request;
@ -1117,7 +1124,9 @@ static const struct afs_call_type afs_RXFSRename = {
int afs_fs_rename(struct afs_fs_cursor *fc,
const char *orig_name,
struct afs_vnode *new_dvnode,
const char *new_name)
const char *new_name,
u64 current_orig_data_version,
u64 current_new_data_version)
{
struct afs_vnode *orig_dvnode = fc->vnode;
struct afs_call *call;
@ -1145,8 +1154,8 @@ int afs_fs_rename(struct afs_fs_cursor *fc,
call->key = fc->key;
call->reply[0] = orig_dvnode;
call->reply[1] = new_dvnode;
call->expected_version = orig_dvnode->status.data_version;
call->expected_version_2 = new_dvnode->status.data_version;
call->expected_version = current_orig_data_version + 1;
call->expected_version_2 = current_new_data_version + 1;
/* marshall the parameters */
bp = call->request;

7
fs/afs/inode.c
View file

@ -395,8 +395,11 @@ int afs_validate(struct afs_vnode *vnode, struct key *key)
if (test_bit(AFS_VNODE_CB_PROMISED, &vnode->flags)) {
if (vnode->cb_s_break != vnode->cb_interest->server->cb_s_break) {
vnode->cb_s_break = vnode->cb_interest->server->cb_s_break;
} else if (test_bit(AFS_VNODE_DIR_VALID, &vnode->flags) &&
!test_bit(AFS_VNODE_ZAP_DATA, &vnode->flags) &&
} else if (vnode->status.type == AFS_FTYPE_DIR &&
test_bit(AFS_VNODE_DIR_VALID, &vnode->flags) &&
vnode->cb_expires_at - 10 > now) {
valid = true;
} else if (!test_bit(AFS_VNODE_ZAP_DATA, &vnode->flags) &&
vnode->cb_expires_at - 10 > now) {
valid = true;
}

19
fs/afs/internal.h
View file

@ -271,6 +271,8 @@ struct afs_net {
atomic_t n_inval; /* Number of invalidations by the server */
atomic_t n_relpg; /* Number of invalidations by releasepage */
atomic_t n_read_dir; /* Number of directory pages read */
atomic_t n_dir_cr; /* Number of directory entry creation edits */
atomic_t n_dir_rm; /* Number of directory entry removal edits */
};
extern const char afs_init_sysname[];
@ -679,6 +681,13 @@ extern const struct dentry_operations afs_fs_dentry_operations;
extern void afs_d_release(struct dentry *);
/*
* dir_edit.c
*/
extern void afs_edit_dir_add(struct afs_vnode *, struct qstr *, struct afs_fid *,
enum afs_edit_dir_reason);
extern void afs_edit_dir_remove(struct afs_vnode *, struct qstr *, enum afs_edit_dir_reason);
/*
* dynroot.c
*/
@ -725,14 +734,14 @@ extern void afs_update_inode_from_status(struct afs_vnode *, struct afs_file_sta
extern int afs_fs_fetch_file_status(struct afs_fs_cursor *, struct afs_volsync *, bool);
extern int afs_fs_give_up_callbacks(struct afs_net *, struct afs_server *);
extern int afs_fs_fetch_data(struct afs_fs_cursor *, struct afs_read *);
extern int afs_fs_create(struct afs_fs_cursor *, const char *, umode_t,
extern int afs_fs_create(struct afs_fs_cursor *, const char *, umode_t, u64,
struct afs_fid *, struct afs_file_status *, struct afs_callback *);
extern int afs_fs_remove(struct afs_fs_cursor *, const char *, bool);
extern int afs_fs_link(struct afs_fs_cursor *, struct afs_vnode *, const char *);
extern int afs_fs_symlink(struct afs_fs_cursor *, const char *, const char *,
extern int afs_fs_remove(struct afs_fs_cursor *, const char *, bool, u64);
extern int afs_fs_link(struct afs_fs_cursor *, struct afs_vnode *, const char *, u64);
extern int afs_fs_symlink(struct afs_fs_cursor *, const char *, const char *, u64,
struct afs_fid *, struct afs_file_status *);
extern int afs_fs_rename(struct afs_fs_cursor *, const char *,
struct afs_vnode *, const char *);
struct afs_vnode *, const char *, u64, u64);
extern int afs_fs_store_data(struct afs_fs_cursor *, struct address_space *,
pgoff_t, pgoff_t, unsigned, unsigned);
extern int afs_fs_setattr(struct afs_fs_cursor *, struct iattr *);

4
fs/afs/proc.c
View file

@ -918,6 +918,10 @@ static int afs_proc_stats_show(struct seq_file *m, void *v)
seq_printf(m, "dir-data: rdpg=%u\n",
atomic_read(&net->n_read_dir));
seq_printf(m, "dir-edit: cr=%u rm=%u\n",
atomic_read(&net->n_dir_cr),
atomic_read(&net->n_dir_rm));
return 0;
}

90
include/trace/events/afs.h
View file

@ -63,6 +63,27 @@ enum afs_vl_operation {
afs_VL_GetCapabilities = 65537, /* AFS Get VL server capabilities */
};
enum afs_edit_dir_op {
afs_edit_dir_create,
afs_edit_dir_create_error,
afs_edit_dir_create_inval,
afs_edit_dir_create_nospc,
afs_edit_dir_delete,
afs_edit_dir_delete_error,
afs_edit_dir_delete_inval,
afs_edit_dir_delete_noent,
};
enum afs_edit_dir_reason {
afs_edit_dir_for_create,
afs_edit_dir_for_link,
afs_edit_dir_for_mkdir,
afs_edit_dir_for_rename,
afs_edit_dir_for_rmdir,
afs_edit_dir_for_symlink,
afs_edit_dir_for_unlink,
};
#endif /* end __AFS_DECLARE_TRACE_ENUMS_ONCE_ONLY */
/*
@ -106,6 +127,25 @@ enum afs_vl_operation {
EM(afs_YFSVL_GetEndpoints, "YFSVL.GetEndpoints") \
E_(afs_VL_GetCapabilities, "VL.GetCapabilities")
#define afs_edit_dir_ops \
EM(afs_edit_dir_create, "create") \
EM(afs_edit_dir_create_error, "c_fail") \
EM(afs_edit_dir_create_inval, "c_invl") \
EM(afs_edit_dir_create_nospc, "c_nspc") \
EM(afs_edit_dir_delete, "delete") \
EM(afs_edit_dir_delete_error, "d_err ") \
EM(afs_edit_dir_delete_inval, "d_invl") \
E_(afs_edit_dir_delete_noent, "d_nent")
#define afs_edit_dir_reasons \
EM(afs_edit_dir_for_create, "Create") \
EM(afs_edit_dir_for_link, "Link ") \
EM(afs_edit_dir_for_mkdir, "MkDir ") \
EM(afs_edit_dir_for_rename, "Rename") \
EM(afs_edit_dir_for_rmdir, "RmDir ") \
EM(afs_edit_dir_for_symlink, "Symlnk") \
E_(afs_edit_dir_for_unlink, "Unlink")
/*
* Export enum symbols via userspace.
@ -118,6 +158,8 @@ enum afs_vl_operation {
afs_call_traces;
afs_fs_operations;
afs_vl_operations;
afs_edit_dir_ops;
afs_edit_dir_reasons;
/*
* Now redefine the EM() and E_() macros to map the enums to the strings that
@ -464,6 +506,54 @@ TRACE_EVENT(afs_call_state,
__entry->ret, __entry->abort)
);
TRACE_EVENT(afs_edit_dir,
TP_PROTO(struct afs_vnode *dvnode,
enum afs_edit_dir_reason why,
enum afs_edit_dir_op op,
unsigned int block,
unsigned int slot,
unsigned int f_vnode,
unsigned int f_unique,
const char *name),
TP_ARGS(dvnode, why, op, block, slot, f_vnode, f_unique, name),
TP_STRUCT__entry(
__field(unsigned int, vnode )
__field(unsigned int, unique )
__field(enum afs_edit_dir_reason, why )
__field(enum afs_edit_dir_op, op )
__field(unsigned int, block )
__field(unsigned short, slot )
__field(unsigned int, f_vnode )
__field(unsigned int, f_unique )
__array(char, name, 18 )
),
TP_fast_assign(
int __len = strlen(name);
__len = min(__len, 17);
__entry->vnode = dvnode->fid.vnode;
__entry->unique = dvnode->fid.unique;
__entry->why = why;
__entry->op = op;
__entry->block = block;
__entry->slot = slot;
__entry->f_vnode = f_vnode;
__entry->f_unique = f_unique;
memcpy(__entry->name, name, __len);
__entry->name[__len] = 0;
),
TP_printk("d=%x:%x %s %s %u[%u] f=%x:%x %s",
__entry->vnode, __entry->unique,
__print_symbolic(__entry->why, afs_edit_dir_reasons),
__print_symbolic(__entry->op, afs_edit_dir_ops),
__entry->block, __entry->slot,
__entry->f_vnode, __entry->f_unique,
__entry->name)
);
#endif /* _TRACE_AFS_H */
/* This part must be outside protection */