- 根目录:
- fs
- exofs
- ios.c
/*
* Copyright (C) 2005, 2006
* Avishay Traeger (avishay@gmail.com)
* Copyright (C) 2008, 2009
* Boaz Harrosh <bharrosh@panasas.com>
*
* 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 <linux/slab.h>
#include <scsi/scsi_device.h>
#include <asm/div64.h>
#include "exofs.h"
#define EXOFS_DBGMSG2(M...) do {} while (0)
/* #define EXOFS_DBGMSG2 EXOFS_DBGMSG */
void exofs_make_credential(u8 cred_a[OSD_CAP_LEN], const struct osd_obj_id *obj)
{
osd_sec_init_nosec_doall_caps(cred_a, obj, false, true);
}
int exofs_read_kern(struct osd_dev *od, u8 *cred, struct osd_obj_id *obj,
u64 offset, void *p, unsigned length)
{
struct osd_request *or = osd_start_request(od, GFP_KERNEL);
/* struct osd_sense_info osi = {.key = 0};*/
int ret;
if (unlikely(!or)) {
EXOFS_DBGMSG("%s: osd_start_request failed.\n", __func__);
return -ENOMEM;
}
ret = osd_req_read_kern(or, obj, offset, p, length);
if (unlikely(ret)) {
EXOFS_DBGMSG("%s: osd_req_read_kern failed.\n", __func__);
goto out;
}
ret = osd_finalize_request(or, 0, cred, NULL);
if (unlikely(ret)) {
EXOFS_DBGMSG("Failed to osd_finalize_request() => %d\n", ret);
goto out;
}
ret = osd_execute_request(or);
if (unlikely(ret))
EXOFS_DBGMSG("osd_execute_request() => %d\n", ret);
/* osd_req_decode_sense(or, ret); */
out:
osd_end_request(or);
return ret;
}
int exofs_get_io_state(struct exofs_layout *layout,
struct exofs_io_state **pios)
{
struct exofs_io_state *ios;
/*TODO: Maybe use kmem_cach per sbi of size
* exofs_io_state_size(layout->s_numdevs)
*/
ios = kzalloc(exofs_io_state_size(layout->s_numdevs), GFP_KERNEL);
if (unlikely(!ios)) {
EXOFS_DBGMSG("Failed kzalloc bytes=%d\n",
exofs_io_state_size(layout->s_numdevs));
*pios = NULL;
return -ENOMEM;
}
ios->layout = layout;
ios->obj.partition = layout->s_pid;
*pios = ios;
return 0;
}
void exofs_put_io_state(struct exofs_io_state *ios)
{
if (ios) {
unsigned i;
for (i = 0; i < ios->numdevs; i++) {
struct exofs_per_dev_state *per_dev = &ios->per_dev[i];
if (per_dev->or)
osd_end_request(per_dev->or);
if (per_dev->bio)
bio_put(per_dev->bio);
}
kfree(ios);
}
}
unsigned exofs_layout_od_id(struct exofs_layout *layout,
osd_id obj_no, unsigned layout_index)
{
/* switch (layout->lay_func) {
case LAYOUT_MOVING_WINDOW:
{*/
unsigned dev_mod = obj_no;
return (layout_index + dev_mod * layout->mirrors_p1) %
layout->s_numdevs;
/* }
case LAYOUT_FUNC_IMPLICT:
return layout->devs[layout_index];
}*/
}
static inline struct osd_dev *exofs_ios_od(struct exofs_io_state *ios,
unsigned layout_index)
{
return ios->layout->s_ods[
exofs_layout_od_id(ios->layout, ios->obj.id, layout_index)];
}
static void _sync_done(struct exofs_io_state *ios, void *p)
{
struct completion *waiting = p;
complete(waiting);
}
static void _last_io(struct kref *kref)
{
struct exofs_io_state *ios = container_of(
kref, struct exofs_io_state, kref);
ios->done(ios, ios->private);
}
static void _done_io(struct osd_request *or, void *p)
{
struct exofs_io_state *ios = p;
kref_put(&ios->kref, _last_io);
}
static int exofs_io_execute(struct exofs_io_state *ios)
{
DECLARE_COMPLETION_ONSTACK(wait);
bool sync = (ios->done == NULL);
int i, ret;
if (sync) {
ios->done = _sync_done;
ios->private = &wait;
}
for (i = 0; i < ios->numdevs; i++) {
struct osd_request *or = ios->per_dev[i].or;
if (unlikely(!or))
continue;
ret = osd_finalize_request(or, 0, ios->cred, NULL);
if (unlikely(ret)) {
EXOFS_DBGMSG("Failed to osd_finalize_request() => %d\n",
ret);
return ret;
}
}
kref_init(&ios->kref);
for (i = 0; i < ios->numdevs; i++) {
struct osd_request *or = ios->per_dev[i].or;
if (unlikely(!or))
continue;
kref_get(&ios->kref);
osd_execute_request_async(or, _done_io, ios);
}
kref_put(&ios->kref, _last_io);
ret = 0;
if (sync) {
wait_for_completion(&wait);
ret = exofs_check_io(ios, NULL);
}
return ret;
}
static void _clear_bio(struct bio *bio)
{
struct bio_vec *bv;
unsigned i;
__bio_for_each_segment(bv, bio, i, 0) {
unsigned this_count = bv->bv_len;
if (likely(PAGE_SIZE == this_count))
clear_highpage(bv->bv_page);
else
zero_user(bv->bv_page, bv->bv_offset, this_count);
}
}
int exofs_check_io(struct exofs_io_state *ios, u64 *resid)
{
enum osd_err_priority acumulated_osd_err = 0;
int acumulated_lin_err = 0;
int i;
for (i = 0; i < ios->numdevs; i++) {
struct osd_sense_info osi;
struct osd_request *or = ios->per_dev[i].or;
int ret;
if (unlikely(!or))
continue;
ret = osd_req_decode_sense(or, &osi);
if (likely(!ret))
continue;
if (OSD_ERR_PRI_CLEAR_PAGES == osi.osd_err_pri) {
/* start read offset passed endof file */
_clear_bio(ios->per_dev[i].bio);
EXOFS_DBGMSG("start read offset passed end of file "
"offset=0x%llx, length=0x%llx\n",
_LLU(ios->per_dev[i].offset),
_LLU(ios->per_dev[i].length));
continue; /* we recovered */
}
if (osi.osd_err_pri >= acumulated_osd_err) {
acumulated_osd_err = osi.osd_err_pri;
acumulated_lin_err = ret;
}
}
/* TODO: raid specific residual calculations */
if (resid) {
if (likely(!acumulated_lin_err))
*resid = 0;
else
*resid = ios->length;
}
return acumulated_lin_err;
}
/*
* L - logical offset into the file
*
* U - The number of bytes in a stripe within a group
*
* U = stripe_unit * group_width
*
* T - The number of bytes striped within a group of component objects
* (before advancing to the next group)
*
* T = stripe_unit * group_width * group_depth
*
* S - The number of bytes striped across all component objects
* before the pattern repeats
*
* S = stripe_unit * group_width * group_depth * group_count
*
* M - The "major" (i.e., across all components) stripe number
*
* M = L / S
*
* G - Counts the groups from the beginning of the major stripe
*
* G = (L - (M * S)) / T [or (L % S) / T]
*
* H - The byte offset within the group
*
* H = (L - (M * S)) % T [or (L % S) % T]
*
* N - The "minor" (i.e., across the group) stripe number
*
* N = H / U
*
* C - The component index coresponding to L
*
* C = (H - (N * U)) / stripe_unit + G * group_width
* [or (L % U) / stripe_unit + G * group_width]
*
* O - The component offset coresponding to L
*
* O = L % stripe_unit + N * stripe_unit + M * group_depth * stripe_unit
*/
struct _striping_info {
u64 obj_offset;
u64 group_length;
unsigned dev;
unsigned unit_off;
};
static void _calc_stripe_info(struct exofs_io_state *ios, u64 file_offset,
struct _striping_info *si)
{
u32 stripe_unit = ios->layout->stripe_unit;
u32 group_width = ios->layout->group_width;
u64 group_depth = ios->layout->group_depth;
u32 U = stripe_unit * group_width;
u64 T = U * group_depth;
u64 S = T * ios->layout->group_count;
u64 M = div64_u64(file_offset, S);
/*
G = (L - (M * S)) / T
H = (L - (M * S)) % T
*/
u64 LmodS = file_offset - M * S;
u32 G = div64_u64(LmodS, T);
u64 H = LmodS - G * T;
u32 N = div_u64(H, U);
/* "H - (N * U)" is just "H % U" so it's bound to u32 */
si->dev = (u32)(H - (N * U)) / stripe_unit + G * group_width;
si->dev *= ios->layout->mirrors_p1;
div_u64_rem(file_offset, stripe_unit, &si->unit_off);
si->obj_offset = si->unit_off + (N * stripe_unit) +
(M * group_depth * stripe_unit);
si->group_length = T - H;
}
static int _add_stripe_unit(struct exofs_io_state *ios, unsigned *cur_pg,
unsigned pgbase, struct exofs_per_dev_state *per_dev,
int cur_len)
{
unsigned pg = *cur_pg;
struct request_queue *q =
osd_request_queue(exofs_ios_od(ios, per_dev->dev));
per_dev->length += cur_len;
if (per_dev->bio == NULL) {
unsigned pages_in_stripe = ios->layout->group_width *
(ios->layout->stripe_unit / PAGE_SIZE);
unsigned bio_size = (ios->nr_pages + pages_in_stripe) /
ios->layout->group_width;
per_dev->bio = bio_kmalloc(GFP_KERNEL, bio_size);
if (unlikely(!per_dev->bio)) {
EXOFS_DBGMSG("Failed to allocate BIO size=%u\n",
bio_size);
return -ENOMEM;
}
}
while (cur_len > 0) {
unsigned pglen = min_t(unsigned, PAGE_SIZE - pgbase, cur_len);
unsigned added_len;
BUG_ON(ios->nr_pages <= pg);
cur_len -= pglen;
added_len = bio_add_pc_page(q, per_dev->bio, ios->pages[pg],
pglen, pgbase);
if (unlikely(pglen != added_len))
return -ENOMEM;
pgbase = 0;
++pg;
}
BUG_ON(cur_len);
*cur_pg = pg;
return 0;
}
static int _prepare_one_group(struct exofs_io_state *ios, u64 length,
struct _striping_info *si)
{
unsigned stripe_unit = ios->layout->stripe_unit;
unsigned mirrors_p1 = ios->layout->mirrors_p1;
unsigned devs_in_group = ios->layout->group_width * mirrors_p1;
unsigned dev = si->dev;
unsigned first_dev = dev - (dev % devs_in_group);
unsigned max_comp = ios->numdevs ? ios->numdevs - mirrors_p1 : 0;
unsigned cur_pg = ios->pages_consumed;
int ret = 0;
while (length) {
struct exofs_per_dev_state *per_dev = &ios->per_dev[dev];
unsigned cur_len, page_off = 0;
if (!per_dev->length) {
per_dev->dev = dev;
if (dev < si->dev) {
per_dev->offset = si->obj_offset + stripe_unit -
si->unit_off;
cur_len = stripe_unit;
} else if (dev == si->dev) {
per_dev->offset = si->obj_offset;
cur_len = stripe_unit - si->unit_off;
page_off = si->unit_off & ~PAGE_MASK;
BUG_ON(page_off && (page_off != ios->pgbase));
} else { /* dev > si->dev */
per_dev->offset = si->obj_offset - si->unit_off;
cur_len = stripe_unit;
}
if (max_comp < dev)
max_comp = dev;
} else {
cur_len = stripe_unit;
}
if (cur_len >= length)
cur_len = length;
ret = _add_stripe_unit(ios, &cur_pg, page_off , per_dev,
cur_len);
if (unlikely(ret))
goto out;
dev += mirrors_p1;
dev = (dev % devs_in_group) + first_dev;
length -= cur_len;
}
out:
ios->numdevs = max_comp + mirrors_p1;
ios->pages_consumed = cur_pg;
return ret;
}
static int _prepare_for_striping(struct exofs_io_state *ios)
{
u64 length = ios->length;
u64 offset = ios->offset;
struct _striping_info si;
int ret = 0;
if (!ios->pages) {
if (ios->kern_buff) {
struct exofs_per_dev_state *per_dev = &ios->per_dev[0];
_calc_stripe_info(ios, ios->offset, &si);
per_dev->offset = si.obj_offset;
per_dev->dev = si.dev;
/* no cross device without page array */
BUG_ON((ios->layout->group_width > 1) &&
(si.unit_off + ios->length >
ios->layout->stripe_unit));
}
ios->numdevs = ios->layout->mirrors_p1;
return 0;
}
while (length) {
_calc_stripe_info(ios, offset, &si);
if (length < si.group_length)
si.group_length = length;
ret = _prepare_one_group(ios, si.group_length, &si);
if (unlikely(ret))
goto out;
offset += si.group_length;
length -= si.group_length;
}
out:
return ret;
}
int exofs_sbi_create(struct exofs_io_state *ios)
{
int i, ret;
for (i = 0; i < ios->layout->s_numdevs; i++) {
struct osd_request *or;
or = osd_start_request(exofs_ios_od(ios, i), GFP_KERNEL);
if (unlikely(!or)) {
EXOFS_ERR("%s: osd_start_request failed\n", __func__);
ret = -ENOMEM;
goto out;
}
ios->per_dev[i].or = or;
ios->numdevs++;
osd_req_create_object(or, &ios->obj);
}
ret = exofs_io_execute(ios);
out:
return ret;
}
int exofs_sbi_remove(struct exofs_io_state *ios)
{
int i, ret;
for (i = 0; i < ios->layout->s_numdevs; i++) {
struct osd_request *or;
or = osd_start_request(exofs_ios_od(ios, i), GFP_KERNEL);
if (unlikely(!or)) {
EXOFS_ERR("%s: osd_start_request failed\n", __func__);
ret = -ENOMEM;
goto out;
}
ios->per_dev[i].or = or;
ios->numdevs++;
osd_req_remove_object(or, &ios->obj);
}
ret = exofs_io_execute(ios);
out:
return ret;
}
static int _sbi_write_mirror(struct exofs_io_state *ios, int cur_comp)
{
struct exofs_per_dev_state *master_dev = &ios->per_dev[cur_comp];
unsigned dev = ios->per_dev[cur_comp].dev;
unsigned last_comp = cur_comp + ios->layout->mirrors_p1;
int ret = 0;
if (ios->pages && !master_dev->length)
return 0; /* Just an empty slot */
for (; cur_comp < last_comp; ++cur_comp, ++dev) {
struct exofs_per_dev_state *per_dev = &ios->per_dev[cur_comp];
struct osd_request *or;
or = osd_start_request(exofs_ios_od(ios, dev), GFP_KERNEL);
if (unlikely(!or)) {
EXOFS_ERR("%s: osd_start_request failed\n", __func__);
ret = -ENOMEM;
goto out;
}
per_dev->or = or;
per_dev->offset = master_dev->offset;
if (ios->pages) {
struct bio *bio;
if (per_dev != master_dev) {
bio = bio_kmalloc(GFP_KERNEL,
master_dev->bio->bi_max_vecs);
if (unlikely(!bio)) {
EXOFS_DBGMSG(
"Failed to allocate BIO size=%u\n",
master_dev->bio->bi_max_vecs);
ret = -ENOMEM;
goto out;
}
__bio_clone(bio, master_dev->bio);
bio->bi_bdev = NULL;
bio->bi_next = NULL;
per_dev->length = master_dev->length;
per_dev->bio = bio;
per_dev->dev = dev;
} else {
bio = master_dev->bio;
/* FIXME: bio_set_dir() */
bio->bi_rw |= REQ_WRITE;
}
osd_req_write(or, &ios->obj, per_dev->offset, bio,
per_dev->length);
EXOFS_DBGMSG("write(0x%llx) offset=0x%llx "
"length=0x%llx dev=%d\n",
_LLU(ios->obj.id), _LLU(per_dev->offset),
_LLU(per_dev->length), dev);
} else if (ios->kern_buff) {
ret = osd_req_write_kern(or, &ios->obj, per_dev->offset,
ios->kern_buff, ios->length);
if (unlikely(ret))
goto out;
EXOFS_DBGMSG2("write_kern(0x%llx) offset=0x%llx "
"length=0x%llx dev=%d\n",
_LLU(ios->obj.id), _LLU(per_dev->offset),
_LLU(ios->length), dev);
} else {
osd_req_set_attributes(or, &ios->obj);
EXOFS_DBGMSG2("obj(0x%llx) set_attributes=%d dev=%d\n",
_LLU(ios->obj.id), ios->out_attr_len, dev);
}
if (ios->out_attr)
osd_req_add_set_attr_list(or, ios->out_attr,
ios->out_attr_len);
if (ios->in_attr)
osd_req_add_get_attr_list(or, ios->in_attr,
ios->in_attr_len);
}
out:
return ret;
}
int exofs_sbi_write(struct exofs_io_state *ios)
{
int i;
int ret;
ret = _prepare_for_striping(ios);
if (unlikely(ret))
return ret;
for (i = 0; i < ios->numdevs; i += ios->layout->mirrors_p1) {
ret = _sbi_write_mirror(ios, i);
if (unlikely(ret))
return ret;
}
ret = exofs_io_execute(ios);
return ret;
}
static int _sbi_read_mirror(struct exofs_io_state *ios, unsigned cur_comp)
{
struct osd_request *or;
struct exofs_per_dev_state *per_dev = &ios->per_dev[cur_comp];
unsigned first_dev = (unsigned)ios->obj.id;
if (ios->pages && !per_dev->length)
return 0; /* Just an empty slot */
first_dev = per_dev->dev + first_dev % ios->layout->mirrors_p1;
or = osd_start_request(exofs_ios_od(ios, first_dev), GFP_KERNEL);
if (unlikely(!or)) {
EXOFS_ERR("%s: osd_start_request failed\n", __func__);
return -ENOMEM;
}
per_dev->or = or;
if (ios->pages) {
osd_req_read(or, &ios->obj, per_dev->offset,
per_dev->bio, per_dev->length);
EXOFS_DBGMSG("read(0x%llx) offset=0x%llx length=0x%llx"
" dev=%d\n", _LLU(ios->obj.id),
_LLU(per_dev->offset), _LLU(per_dev->length),
first_dev);
} else if (ios->kern_buff) {
int ret = osd_req_read_kern(or, &ios->obj, per_dev->offset,
ios->kern_buff, ios->length);
EXOFS_DBGMSG2("read_kern(0x%llx) offset=0x%llx "
"length=0x%llx dev=%d ret=>%d\n",
_LLU(ios->obj.id), _LLU(per_dev->offset),
_LLU(ios->length), first_dev, ret);
if (unlikely(ret))
return ret;
} else {
osd_req_get_attributes(or, &ios->obj);
EXOFS_DBGMSG2("obj(0x%llx) get_attributes=%d dev=%d\n",
_LLU(ios->obj.id), ios->in_attr_len, first_dev);
}
if (ios->out_attr)
osd_req_add_set_attr_list(or, ios->out_attr, ios->out_attr_len);
if (ios->in_attr)
osd_req_add_get_attr_list(or, ios->in_attr, ios->in_attr_len);
return 0;
}
int exofs_sbi_read(struct exofs_io_state *ios)
{
int i;
int ret;
ret = _prepare_for_striping(ios);
if (unlikely(ret))
return ret;
for (i = 0; i < ios->numdevs; i += ios->layout->mirrors_p1) {
ret = _sbi_read_mirror(ios, i);
if (unlikely(ret))
return ret;
}
ret = exofs_io_execute(ios);
return ret;
}
int extract_attr_from_ios(struct exofs_io_state *ios, struct osd_attr *attr)
{
struct osd_attr cur_attr = {.attr_page = 0}; /* start with zeros */
void *iter = NULL;
int nelem;
do {
nelem = 1;
osd_req_decode_get_attr_list(ios->per_dev[0].or,
&cur_attr, &nelem, &iter);
if ((cur_attr.attr_page == attr->attr_page) &&
(cur_attr.attr_id == attr->attr_id)) {
attr->len = cur_attr.len;
attr->val_ptr = cur_attr.val_ptr;
return 0;
}
} while (iter);
return -EIO;
}
static int _truncate_mirrors(struct exofs_io_state *ios, unsigned cur_comp,
struct osd_attr *attr)
{
int last_comp = cur_comp + ios->layout->mirrors_p1;
for (; cur_comp < last_comp; ++cur_comp) {
struct exofs_per_dev_state *per_dev = &ios->per_dev[cur_comp];
struct osd_request *or;
or = osd_start_request(exofs_ios_od(ios, cur_comp), GFP_KERNEL);
if (unlikely(!or)) {
EXOFS_ERR("%s: osd_start_request failed\n", __func__);
return -ENOMEM;
}
per_dev->or = or;
osd_req_set_attributes(or, &ios->obj);
osd_req_add_set_attr_list(or, attr, 1);
}
return 0;
}
int exofs_oi_truncate(struct exofs_i_info *oi, u64 size)
{
struct exofs_sb_info *sbi = oi->vfs_inode.i_sb->s_fs_info;
struct exofs_io_state *ios;
struct exofs_trunc_attr {
struct osd_attr attr;
__be64 newsize;
} *size_attrs;
struct _striping_info si;
int i, ret;
ret = exofs_get_io_state(&sbi->layout, &ios);
if (unlikely(ret))
return ret;
size_attrs = kcalloc(ios->layout->group_width, sizeof(*size_attrs),
GFP_KERNEL);
if (unlikely(!size_attrs)) {
ret = -ENOMEM;
goto out;
}
ios->obj.id = exofs_oi_objno(oi);
ios->cred = oi->i_cred;
ios->numdevs = ios->layout->s_numdevs;
_calc_stripe_info(ios, size, &si);
for (i = 0; i < ios->layout->group_width; ++i) {
struct exofs_trunc_attr *size_attr = &size_attrs[i];
u64 obj_size;
if (i < si.dev)
obj_size = si.obj_offset +
ios->layout->stripe_unit - si.unit_off;
else if (i == si.dev)
obj_size = si.obj_offset;
else /* i > si.dev */
obj_size = si.obj_offset - si.unit_off;
size_attr->newsize = cpu_to_be64(obj_size);
size_attr->attr = g_attr_logical_length;
size_attr->attr.val_ptr = &size_attr->newsize;
ret = _truncate_mirrors(ios, i * ios->layout->mirrors_p1,
&size_attr->attr);
if (unlikely(ret))
goto out;
}
ret = exofs_io_execute(ios);
out:
kfree(size_attrs);
exofs_put_io_state(ios);
return ret;
}