- 根目录:
- block
- partitions
- aix.c
/*
* fs/partitions/aix.c
*
* Copyright (C) 2012-2013 Philippe De Muyter <phdm@macqel.be>
*/
#include "check.h"
#include "aix.h"
struct lvm_rec {
char lvm_id[4]; /* "_LVM" */
char reserved4[16];
__be32 lvmarea_len;
__be32 vgda_len;
__be32 vgda_psn[2];
char reserved36[10];
__be16 pp_size; /* log2(pp_size) */
char reserved46[12];
__be16 version;
};
struct vgda {
__be32 secs;
__be32 usec;
char reserved8[16];
__be16 numlvs;
__be16 maxlvs;
__be16 pp_size;
__be16 numpvs;
__be16 total_vgdas;
__be16 vgda_size;
};
struct lvd {
__be16 lv_ix;
__be16 res2;
__be16 res4;
__be16 maxsize;
__be16 lv_state;
__be16 mirror;
__be16 mirror_policy;
__be16 num_lps;
__be16 res10[8];
};
struct lvname {
char name[64];
};
struct ppe {
__be16 lv_ix;
unsigned short res2;
unsigned short res4;
__be16 lp_ix;
unsigned short res8[12];
};
struct pvd {
char reserved0[16];
__be16 pp_count;
char reserved18[2];
__be32 psn_part1;
char reserved24[8];
struct ppe ppe[1016];
};
#define LVM_MAXLVS 256
/**
* last_lba(): return number of last logical block of device
* @bdev: block device
*
* Description: Returns last LBA value on success, 0 on error.
* This is stored (by sd and ide-geometry) in
* the part[0] entry for this disk, and is the number of
* physical sectors available on the disk.
*/
static u64 last_lba(struct block_device *bdev)
{
if (!bdev || !bdev->bd_inode)
return 0;
return (bdev->bd_inode->i_size >> 9) - 1ULL;
}
/**
* read_lba(): Read bytes from disk, starting at given LBA
* @state
* @lba
* @buffer
* @count
*
* Description: Reads @count bytes from @state->bdev into @buffer.
* Returns number of bytes read on success, 0 on error.
*/
static size_t read_lba(struct parsed_partitions *state, u64 lba, u8 *buffer,
size_t count)
{
size_t totalreadcount = 0;
if (!buffer || lba + count / 512 > last_lba(state->bdev))
return 0;
while (count) {
int copied = 512;
Sector sect;
unsigned char *data = read_part_sector(state, lba++, §);
if (!data)
break;
if (copied > count)
copied = count;
memcpy(buffer, data, copied);
put_dev_sector(sect);
buffer += copied;
totalreadcount += copied;
count -= copied;
}
return totalreadcount;
}
/**
* alloc_pvd(): reads physical volume descriptor
* @state
* @lba
*
* Description: Returns pvd on success, NULL on error.
* Allocates space for pvd and fill it with disk blocks at @lba
* Notes: remember to free pvd when you're done!
*/
static struct pvd *alloc_pvd(struct parsed_partitions *state, u32 lba)
{
size_t count = sizeof(struct pvd);
struct pvd *p;
p = kmalloc(count, GFP_KERNEL);
if (!p)
return NULL;
if (read_lba(state, lba, (u8 *) p, count) < count) {
kfree(p);
return NULL;
}
return p;
}
/**
* alloc_lvn(): reads logical volume names
* @state
* @lba
*
* Description: Returns lvn on success, NULL on error.
* Allocates space for lvn and fill it with disk blocks at @lba
* Notes: remember to free lvn when you're done!
*/
static struct lvname *alloc_lvn(struct parsed_partitions *state, u32 lba)
{
size_t count = sizeof(struct lvname) * LVM_MAXLVS;
struct lvname *p;
p = kmalloc(count, GFP_KERNEL);
if (!p)
return NULL;
if (read_lba(state, lba, (u8 *) p, count) < count) {
kfree(p);
return NULL;
}
return p;
}
int aix_partition(struct parsed_partitions *state)
{
int ret = 0;
Sector sect;
unsigned char *d;
u32 pp_bytes_size;
u32 pp_blocks_size = 0;
u32 vgda_sector = 0;
u32 vgda_len = 0;
int numlvs = 0;
struct pvd *pvd;
struct lv_info {
unsigned short pps_per_lv;
unsigned short pps_found;
unsigned char lv_is_contiguous;
} *lvip;
struct lvname *n = NULL;
d = read_part_sector(state, 7, §);
if (d) {
struct lvm_rec *p = (struct lvm_rec *)d;
u16 lvm_version = be16_to_cpu(p->version);
char tmp[64];
if (lvm_version == 1) {
int pp_size_log2 = be16_to_cpu(p->pp_size);
pp_bytes_size = 1 << pp_size_log2;
pp_blocks_size = pp_bytes_size / 512;
snprintf(tmp, sizeof(tmp),
" AIX LVM header version %u found\n",
lvm_version);
vgda_len = be32_to_cpu(p->vgda_len);
vgda_sector = be32_to_cpu(p->vgda_psn[0]);
} else {
snprintf(tmp, sizeof(tmp),
" unsupported AIX LVM version %d found\n",
lvm_version);
}
strlcat(state->pp_buf, tmp, PAGE_SIZE);
put_dev_sector(sect);
}
if (vgda_sector && (d = read_part_sector(state, vgda_sector, §))) {
struct vgda *p = (struct vgda *)d;
numlvs = be16_to_cpu(p->numlvs);
put_dev_sector(sect);
}
lvip = kcalloc(state->limit, sizeof(struct lv_info), GFP_KERNEL);
if (!lvip)
return 0;
if (numlvs && (d = read_part_sector(state, vgda_sector + 1, §))) {
struct lvd *p = (struct lvd *)d;
int i;
n = alloc_lvn(state, vgda_sector + vgda_len - 33);
if (n) {
int foundlvs = 0;
for (i = 0; foundlvs < numlvs && i < state->limit; i += 1) {
lvip[i].pps_per_lv = be16_to_cpu(p[i].num_lps);
if (lvip[i].pps_per_lv)
foundlvs += 1;
}
}
put_dev_sector(sect);
}
pvd = alloc_pvd(state, vgda_sector + 17);
if (pvd) {
int numpps = be16_to_cpu(pvd->pp_count);
int psn_part1 = be32_to_cpu(pvd->psn_part1);
int i;
int cur_lv_ix = -1;
int next_lp_ix = 1;
int lp_ix;
for (i = 0; i < numpps; i += 1) {
struct ppe *p = pvd->ppe + i;
unsigned int lv_ix;
lp_ix = be16_to_cpu(p->lp_ix);
if (!lp_ix) {
next_lp_ix = 1;
continue;
}
lv_ix = be16_to_cpu(p->lv_ix) - 1;
if (lv_ix >= state->limit) {
cur_lv_ix = -1;
continue;
}
lvip[lv_ix].pps_found += 1;
if (lp_ix == 1) {
cur_lv_ix = lv_ix;
next_lp_ix = 1;
} else if (lv_ix != cur_lv_ix || lp_ix != next_lp_ix) {
next_lp_ix = 1;
continue;
}
if (lp_ix == lvip[lv_ix].pps_per_lv) {
char tmp[70];
put_partition(state, lv_ix + 1,
(i + 1 - lp_ix) * pp_blocks_size + psn_part1,
lvip[lv_ix].pps_per_lv * pp_blocks_size);
snprintf(tmp, sizeof(tmp), " <%s>\n",
n[lv_ix].name);
strlcat(state->pp_buf, tmp, PAGE_SIZE);
lvip[lv_ix].lv_is_contiguous = 1;
ret = 1;
next_lp_ix = 1;
} else
next_lp_ix += 1;
}
for (i = 0; i < state->limit; i += 1)
if (lvip[i].pps_found && !lvip[i].lv_is_contiguous)
pr_warn("partition %s (%u pp's found) is "
"not contiguous\n",
n[i].name, lvip[i].pps_found);
kfree(pvd);
}
kfree(n);
kfree(lvip);
return ret;
}