Commit d194139c authored by Marcin Slusarz's avatar Marcin Slusarz Committed by Jens Axboe

cdrom: reduce stack usage of mmc_ioctl_dvd_read_struct

1. kmalloc 192 bytes in dvd_read_bca (which is inlined into dvd_read_struct)
2. Pass struct packet_command to all dvd_read_* functions.

Checkstack output:
Before: mmc_ioctl_dvd_read_struct:         280
After:  mmc_ioctl_dvd_read_struct:         56
Signed-off-by: default avatarMarcin Slusarz <[email protected]>
Cc: Bartlomiej Zolnierkiewicz <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Jens Axboe <[email protected]>
Signed-off-by: default avatarJens Axboe <[email protected]>
parent 3147c531
...@@ -1712,29 +1712,30 @@ static int dvd_do_auth(struct cdrom_device_info *cdi, dvd_authinfo *ai) ...@@ -1712,29 +1712,30 @@ static int dvd_do_auth(struct cdrom_device_info *cdi, dvd_authinfo *ai)
return 0; return 0;
} }
static int dvd_read_physical(struct cdrom_device_info *cdi, dvd_struct *s) static int dvd_read_physical(struct cdrom_device_info *cdi, dvd_struct *s,
struct packet_command *cgc)
{ {
unsigned char buf[21], *base; unsigned char buf[21], *base;
struct dvd_layer *layer; struct dvd_layer *layer;
struct packet_command cgc;
struct cdrom_device_ops *cdo = cdi->ops; struct cdrom_device_ops *cdo = cdi->ops;
int ret, layer_num = s->physical.layer_num; int ret, layer_num = s->physical.layer_num;
if (layer_num >= DVD_LAYERS) if (layer_num >= DVD_LAYERS)
return -EINVAL; return -EINVAL;
init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ); init_cdrom_command(cgc, buf, sizeof(buf), CGC_DATA_READ);
cgc.cmd[0] = GPCMD_READ_DVD_STRUCTURE; cgc->cmd[0] = GPCMD_READ_DVD_STRUCTURE;
cgc.cmd[6] = layer_num; cgc->cmd[6] = layer_num;
cgc.cmd[7] = s->type; cgc->cmd[7] = s->type;
cgc.cmd[9] = cgc.buflen & 0xff; cgc->cmd[9] = cgc->buflen & 0xff;
/* /*
* refrain from reporting errors on non-existing layers (mainly) * refrain from reporting errors on non-existing layers (mainly)
*/ */
cgc.quiet = 1; cgc->quiet = 1;
if ((ret = cdo->generic_packet(cdi, &cgc))) ret = cdo->generic_packet(cdi, cgc);
if (ret)
return ret; return ret;
base = &buf[4]; base = &buf[4];
...@@ -1762,21 +1763,22 @@ static int dvd_read_physical(struct cdrom_device_info *cdi, dvd_struct *s) ...@@ -1762,21 +1763,22 @@ static int dvd_read_physical(struct cdrom_device_info *cdi, dvd_struct *s)
return 0; return 0;
} }
static int dvd_read_copyright(struct cdrom_device_info *cdi, dvd_struct *s) static int dvd_read_copyright(struct cdrom_device_info *cdi, dvd_struct *s,
struct packet_command *cgc)
{ {
int ret; int ret;
u_char buf[8]; u_char buf[8];
struct packet_command cgc;
struct cdrom_device_ops *cdo = cdi->ops; struct cdrom_device_ops *cdo = cdi->ops;
init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ); init_cdrom_command(cgc, buf, sizeof(buf), CGC_DATA_READ);
cgc.cmd[0] = GPCMD_READ_DVD_STRUCTURE; cgc->cmd[0] = GPCMD_READ_DVD_STRUCTURE;
cgc.cmd[6] = s->copyright.layer_num; cgc->cmd[6] = s->copyright.layer_num;
cgc.cmd[7] = s->type; cgc->cmd[7] = s->type;
cgc.cmd[8] = cgc.buflen >> 8; cgc->cmd[8] = cgc->buflen >> 8;
cgc.cmd[9] = cgc.buflen & 0xff; cgc->cmd[9] = cgc->buflen & 0xff;
if ((ret = cdo->generic_packet(cdi, &cgc))) ret = cdo->generic_packet(cdi, cgc);
if (ret)
return ret; return ret;
s->copyright.cpst = buf[4]; s->copyright.cpst = buf[4];
...@@ -1785,79 +1787,89 @@ static int dvd_read_copyright(struct cdrom_device_info *cdi, dvd_struct *s) ...@@ -1785,79 +1787,89 @@ static int dvd_read_copyright(struct cdrom_device_info *cdi, dvd_struct *s)
return 0; return 0;
} }
static int dvd_read_disckey(struct cdrom_device_info *cdi, dvd_struct *s) static int dvd_read_disckey(struct cdrom_device_info *cdi, dvd_struct *s,
struct packet_command *cgc)
{ {
int ret, size; int ret, size;
u_char *buf; u_char *buf;
struct packet_command cgc;
struct cdrom_device_ops *cdo = cdi->ops; struct cdrom_device_ops *cdo = cdi->ops;
size = sizeof(s->disckey.value) + 4; size = sizeof(s->disckey.value) + 4;
if ((buf = kmalloc(size, GFP_KERNEL)) == NULL) buf = kmalloc(size, GFP_KERNEL);
if (!buf)
return -ENOMEM; return -ENOMEM;
init_cdrom_command(&cgc, buf, size, CGC_DATA_READ); init_cdrom_command(cgc, buf, size, CGC_DATA_READ);
cgc.cmd[0] = GPCMD_READ_DVD_STRUCTURE; cgc->cmd[0] = GPCMD_READ_DVD_STRUCTURE;
cgc.cmd[7] = s->type; cgc->cmd[7] = s->type;
cgc.cmd[8] = size >> 8; cgc->cmd[8] = size >> 8;
cgc.cmd[9] = size & 0xff; cgc->cmd[9] = size & 0xff;
cgc.cmd[10] = s->disckey.agid << 6; cgc->cmd[10] = s->disckey.agid << 6;
if (!(ret = cdo->generic_packet(cdi, &cgc))) ret = cdo->generic_packet(cdi, cgc);
if (!ret)
memcpy(s->disckey.value, &buf[4], sizeof(s->disckey.value)); memcpy(s->disckey.value, &buf[4], sizeof(s->disckey.value));
kfree(buf); kfree(buf);
return ret; return ret;
} }
static int dvd_read_bca(struct cdrom_device_info *cdi, dvd_struct *s) static int dvd_read_bca(struct cdrom_device_info *cdi, dvd_struct *s,
struct packet_command *cgc)
{ {
int ret; int ret, size = 4 + 188;
u_char buf[4 + 188]; u_char *buf;
struct packet_command cgc;
struct cdrom_device_ops *cdo = cdi->ops; struct cdrom_device_ops *cdo = cdi->ops;
init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ); buf = kmalloc(size, GFP_KERNEL);
cgc.cmd[0] = GPCMD_READ_DVD_STRUCTURE; if (!buf)
cgc.cmd[7] = s->type; return -ENOMEM;
cgc.cmd[9] = cgc.buflen & 0xff;
if ((ret = cdo->generic_packet(cdi, &cgc))) init_cdrom_command(cgc, buf, size, CGC_DATA_READ);
return ret; cgc->cmd[0] = GPCMD_READ_DVD_STRUCTURE;
cgc->cmd[7] = s->type;
cgc->cmd[9] = cgc->buflen & 0xff;
ret = cdo->generic_packet(cdi, cgc);
if (ret)
goto out;
s->bca.len = buf[0] << 8 | buf[1]; s->bca.len = buf[0] << 8 | buf[1];
if (s->bca.len < 12 || s->bca.len > 188) { if (s->bca.len < 12 || s->bca.len > 188) {
cdinfo(CD_WARNING, "Received invalid BCA length (%d)\n", s->bca.len); cdinfo(CD_WARNING, "Received invalid BCA length (%d)\n", s->bca.len);
return -EIO; ret = -EIO;
goto out;
} }
memcpy(s->bca.value, &buf[4], s->bca.len); memcpy(s->bca.value, &buf[4], s->bca.len);
ret = 0;
return 0; out:
kfree(buf);
return ret;
} }
static int dvd_read_manufact(struct cdrom_device_info *cdi, dvd_struct *s) static int dvd_read_manufact(struct cdrom_device_info *cdi, dvd_struct *s,
struct packet_command *cgc)
{ {
int ret = 0, size; int ret = 0, size;
u_char *buf; u_char *buf;
struct packet_command cgc;
struct cdrom_device_ops *cdo = cdi->ops; struct cdrom_device_ops *cdo = cdi->ops;
size = sizeof(s->manufact.value) + 4; size = sizeof(s->manufact.value) + 4;
if ((buf = kmalloc(size, GFP_KERNEL)) == NULL) buf = kmalloc(size, GFP_KERNEL);
if (!buf)
return -ENOMEM; return -ENOMEM;
init_cdrom_command(&cgc, buf, size, CGC_DATA_READ); init_cdrom_command(cgc, buf, size, CGC_DATA_READ);
cgc.cmd[0] = GPCMD_READ_DVD_STRUCTURE; cgc->cmd[0] = GPCMD_READ_DVD_STRUCTURE;
cgc.cmd[7] = s->type; cgc->cmd[7] = s->type;
cgc.cmd[8] = size >> 8; cgc->cmd[8] = size >> 8;
cgc.cmd[9] = size & 0xff; cgc->cmd[9] = size & 0xff;
if ((ret = cdo->generic_packet(cdi, &cgc))) { ret = cdo->generic_packet(cdi, cgc);
kfree(buf); if (ret)
return ret; goto out;
}
s->manufact.len = buf[0] << 8 | buf[1]; s->manufact.len = buf[0] << 8 | buf[1];
if (s->manufact.len < 0 || s->manufact.len > 2048) { if (s->manufact.len < 0 || s->manufact.len > 2048) {
...@@ -1868,27 +1880,29 @@ static int dvd_read_manufact(struct cdrom_device_info *cdi, dvd_struct *s) ...@@ -1868,27 +1880,29 @@ static int dvd_read_manufact(struct cdrom_device_info *cdi, dvd_struct *s)
memcpy(s->manufact.value, &buf[4], s->manufact.len); memcpy(s->manufact.value, &buf[4], s->manufact.len);
} }
out:
kfree(buf); kfree(buf);
return ret; return ret;
} }
static int dvd_read_struct(struct cdrom_device_info *cdi, dvd_struct *s) static int dvd_read_struct(struct cdrom_device_info *cdi, dvd_struct *s,
struct packet_command *cgc)
{ {
switch (s->type) { switch (s->type) {
case DVD_STRUCT_PHYSICAL: case DVD_STRUCT_PHYSICAL:
return dvd_read_physical(cdi, s); return dvd_read_physical(cdi, s, cgc);
case DVD_STRUCT_COPYRIGHT: case DVD_STRUCT_COPYRIGHT:
return dvd_read_copyright(cdi, s); return dvd_read_copyright(cdi, s, cgc);
case DVD_STRUCT_DISCKEY: case DVD_STRUCT_DISCKEY:
return dvd_read_disckey(cdi, s); return dvd_read_disckey(cdi, s, cgc);
case DVD_STRUCT_BCA: case DVD_STRUCT_BCA:
return dvd_read_bca(cdi, s); return dvd_read_bca(cdi, s, cgc);
case DVD_STRUCT_MANUFACT: case DVD_STRUCT_MANUFACT:
return dvd_read_manufact(cdi, s); return dvd_read_manufact(cdi, s, cgc);
default: default:
cdinfo(CD_WARNING, ": Invalid DVD structure read requested (%d)\n", cdinfo(CD_WARNING, ": Invalid DVD structure read requested (%d)\n",
...@@ -3027,7 +3041,8 @@ static noinline int mmc_ioctl_cdrom_pause_resume(struct cdrom_device_info *cdi, ...@@ -3027,7 +3041,8 @@ static noinline int mmc_ioctl_cdrom_pause_resume(struct cdrom_device_info *cdi,
} }
static noinline int mmc_ioctl_dvd_read_struct(struct cdrom_device_info *cdi, static noinline int mmc_ioctl_dvd_read_struct(struct cdrom_device_info *cdi,
void __user *arg) void __user *arg,
struct packet_command *cgc)
{ {
int ret; int ret;
dvd_struct *s; dvd_struct *s;
...@@ -3046,7 +3061,7 @@ static noinline int mmc_ioctl_dvd_read_struct(struct cdrom_device_info *cdi, ...@@ -3046,7 +3061,7 @@ static noinline int mmc_ioctl_dvd_read_struct(struct cdrom_device_info *cdi,
return -EFAULT; return -EFAULT;
} }
ret = dvd_read_struct(cdi, s); ret = dvd_read_struct(cdi, s, cgc);
if (ret) if (ret)
goto out; goto out;
...@@ -3132,7 +3147,7 @@ static int mmc_ioctl(struct cdrom_device_info *cdi, unsigned int cmd, ...@@ -3132,7 +3147,7 @@ static int mmc_ioctl(struct cdrom_device_info *cdi, unsigned int cmd,
case CDROMRESUME: case CDROMRESUME:
return mmc_ioctl_cdrom_pause_resume(cdi, &cgc, cmd); return mmc_ioctl_cdrom_pause_resume(cdi, &cgc, cmd);
case DVD_READ_STRUCT: case DVD_READ_STRUCT:
return mmc_ioctl_dvd_read_struct(cdi, userptr); return mmc_ioctl_dvd_read_struct(cdi, userptr, &cgc);
case DVD_AUTH: case DVD_AUTH:
return mmc_ioctl_dvd_auth(cdi, userptr); return mmc_ioctl_dvd_auth(cdi, userptr);
case CDROM_NEXT_WRITABLE: case CDROM_NEXT_WRITABLE:
......
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