Re: [GRUB PATCH] xfs: accept filesystem with sparse inodes
On Tue, May 15, 2018 at 02:55:55PM -0500, Eric Sandeen wrote: > The sparse inode metadata format became a mkfs.xfs default in > xfsprogs-4.16.0, and such filesystems are now rejected by grub as > containing an incompatible feature. > > In essence, this feature allows xfs to allocate inodes into fragmented > freespace. (Without this feature, if xfs could not allocate contiguous > space for 64 new inodes, inode creation would fail.) > > In practice, the disk format change is restricted to the inode btree, > which as far as I can tell is not used by grub. If all you're doing > today is parsing a directory, reading an inode number, and converting > that inode number to a disk location, then ignoring this feature > should be fine, so I've added it to XFS_SB_FEAT_INCOMPAT_SUPPORTED > > I did some brief testing of this patch by hacking up the regression > tests to completely fragment freespace on the test xfs filesystem, and > then write a large-ish number of inodes to consume any existing > contiguous 64-inode chunk. This way any files the grub tests add and > traverse would be in such a fragmented inode allocation. Tests passed, > but I'm not sure how to cleanly integrate that into the test harness. > > Signed-off-by: Eric Sandeen Eric, thank you for posting the patch. LGTM. Chris, may I ask you to test it and add your "Tested-by:" if it works? Daniel ___ Grub-devel mailing list Grub-devel@gnu.org https://lists.gnu.org/mailman/listinfo/grub-devel
Re: FTDI serial console support?
On Wed, May 16, 2018 at 06:21:17AM +0200, Petter Gustad wrote: > From: Daniel Kiper > Subject: Re: FTDI serial console support? > Date: Tue, 15 May 2018 22:00:06 +0200 > > > On Fri, May 11, 2018 at 03:55:36PM +0200, Petter Gustad wrote: > >> > >> Is there a way to specify a FTDI based serial console using > >> GRUB_TERMINAL, GRUB_SERIAL_COMMAND, or some other variable? If yes, > >> what is the syntax? > >> > >> BTW my serial port adapter matches the vendor id and device id given > >> in grub-core/bus/usb/serial/ftdi.c: > >> > >> Bus 001 Device 008: ID 0403:6001 Future Technology Devices International, > >> Ltd FT232 Serial (UART) IC > > > > Have you tried usbserial_ftdi, e.g. GRUB_TERMINAL=usbserial_ftdi? > > Just guessing... > > Yes, I tried (as I found the "usbserial_ftdi" string in the source) > the but grub-mkconfig does not accecpt it: > > grub-mkconfig -o /boot/grub/grub.cfg > Invalid output terminal "usbserial_ftdi" > > Currently I have this: > > GRUB_CMDLINE_LINUX_DEFAULT="console=tty0 console=ttyUSB0,115200n8" > #GRUB_TERMINAL="console serial" > GRUB_TERMINAL="serial" > GRUB_SERIAL_COMMAND="usbserial_ftdi --speed=115200 --unit=0 --word=8 > --parity=no --stop=1" > > But this does not seem to work either, even though I do get console > output on my USB serial after the kernel has loaded (due to > GRUB_CMDLINE_LINUX being passed to the kernel), e.g. I can do "echo > hello > /dev/console" and read "hello" on the USB serial output. When > I do a "reboot" I observe messages about unmounting filesystems etc. > > I was hoping to be able to select kernels and options in grub using > the USB serial line. Please take a look here: https://www.coreboot.org/GRUB2#On_a_USB_serial_or_USB_debug_adapter I hope that helps. Daniel ___ Grub-devel mailing list Grub-devel@gnu.org https://lists.gnu.org/mailman/listinfo/grub-devel
Re: [PATCH] mbi: use per segment a separate relocator chunk
On Tue, May 15, 2018 at 09:18:18PM +0200, Alexander Boettcher wrote: > On 15.05.2018 21:10, Alexander Boettcher wrote: > >>I assume that a given ELF PHDR address/size does not cover VGA memory or > >>anything like that, > > > >No. > > > >>so, I am not sure what exactly overwrites this region. > >>grub_memset() in current line 161 at some point? > > > >No. During grub_relocator_prepare_reloc the overwrite happens, if i'm > >not wrong. > > > >An (artificial) example, imagine two ELF PHDRs, e.g. > > > > ??[0x8000-0x9000) and > > ??[0x200-0x210). > > > >Without this patch grub calculates one relocator chunk of size 0x20f8000 > >(0x210 - 0x8000) and places it at some higher memory, e.g. > >[0x300 - 0x30f8000). During the invocation of > > Must be [0x300-0x50f8000) > > >grub_relocator_prepare_reloc the memory gets copied from > > > >[0x300-0x30f8000) to [0x8000-0x210) > > Must be [0x300-0x50f8000) to [0x8000-0x210) It seems to me that it happens a bit later. AIUI grub_relocator_prepare_reloc() prepare movers which are executed when main GRUB code is left, e.g relst() call from grub_relocator32_boot(). And the movers do bad job. Well, they were told to do so... Anyway, I think that the comment should be a bit more clear about it. Daniel ___ Grub-devel mailing list Grub-devel@gnu.org https://lists.gnu.org/mailman/listinfo/grub-devel
[PATCH 6/9] btrfs: refactor the code that read from disk
This is a preparatory patch, to help the adding of the RAID 5/6 recovery
code. In case of availability of all disks, this code is good for all the
RAID profiles. However in case of failure, the error handling is quite
different. Refactoring this code increases the general readability.
Signed-off-by: Goffredo Baroncelli
---
grub-core/fs/btrfs.c | 85 +---
1 file changed, 49 insertions(+), 36 deletions(-)
diff --git a/grub-core/fs/btrfs.c b/grub-core/fs/btrfs.c
index 51f300829..63651928b 100644
--- a/grub-core/fs/btrfs.c
+++ b/grub-core/fs/btrfs.c
@@ -625,6 +625,47 @@ find_device (struct grub_btrfs_data *data, grub_uint64_t
id)
return ctx.dev_found;
}
+static grub_err_t
+btrfs_read_from_chunk (struct grub_btrfs_data *data,
+ struct grub_btrfs_chunk_item *chunk,
+ grub_uint64_t stripen, grub_uint64_t stripe_offset,
+ int redundancy, grub_uint64_t csize,
+ void *buf)
+{
+
+struct grub_btrfs_chunk_stripe *stripe;
+grub_disk_addr_t paddr;
+grub_device_t dev;
+grub_err_t err;
+
+stripe = (struct grub_btrfs_chunk_stripe *) (chunk + 1);
+/* Right now the redundancy handling is easy.
+ With RAID5-like it will be more difficult. */
+stripe += stripen + redundancy;
+
+paddr = grub_le_to_cpu64 (stripe->offset) + stripe_offset;
+
+grub_dprintf ("btrfs", "stripe %" PRIxGRUB_UINT64_T
+ " maps to 0x%" PRIxGRUB_UINT64_T "\n",
+ stripen, stripe->offset);
+grub_dprintf ("btrfs", "reading paddr 0x%" PRIxGRUB_UINT64_T "\n", paddr);
+
+dev = find_device (data, stripe->device_id);
+if (!dev)
+ {
+ grub_dprintf ("btrfs",
+ "couldn't find a necessary member device "
+ "of multi-device filesystem\n");
+ grub_errno = GRUB_ERR_NONE;
+ return GRUB_ERR_READ_ERROR;
+ }
+
+err = grub_disk_read (dev->disk, paddr >> GRUB_DISK_SECTOR_BITS,
+ paddr & (GRUB_DISK_SECTOR_SIZE - 1),
+ csize, buf);
+return err;
+}
+
static grub_err_t
grub_btrfs_read_logical (struct grub_btrfs_data *data, grub_disk_addr_t addr,
void *buf, grub_size_t size, int recursion_depth)
@@ -638,7 +679,6 @@ grub_btrfs_read_logical (struct grub_btrfs_data *data,
grub_disk_addr_t addr,
grub_err_t err = 0;
struct grub_btrfs_key key_out;
int challoc = 0;
- grub_device_t dev;
struct grub_btrfs_key key_in;
grub_size_t chsize;
grub_disk_addr_t chaddr;
@@ -879,42 +919,15 @@ grub_btrfs_read_logical (struct grub_btrfs_data *data,
grub_disk_addr_t addr,
for (i = 0; i < redundancy; i++)
{
- struct grub_btrfs_chunk_stripe *stripe;
- grub_disk_addr_t paddr;
-
- stripe = (struct grub_btrfs_chunk_stripe *) (chunk + 1);
- /* Right now the redundancy handling is easy.
- With RAID5-like it will be more difficult. */
- stripe += stripen + i;
-
- paddr = grub_le_to_cpu64 (stripe->offset) + stripe_offset;
-
- grub_dprintf ("btrfs", "stripe %" PRIxGRUB_UINT64_T
- " maps to 0x%" PRIxGRUB_UINT64_T "\n",
- stripen, stripe->offset);
- grub_dprintf ("btrfs", "reading paddr 0x%" PRIxGRUB_UINT64_T
- "\n", paddr);
-
- dev = find_device (data, stripe->device_id);
- if (!dev)
- {
- grub_dprintf ("btrfs",
- "couldn't find a necessary member device "
- "of multi-device filesystem\n");
- err = grub_errno;
- grub_errno = GRUB_ERR_NONE;
- continue;
- }
-
- err = grub_disk_read (dev->disk, paddr >> GRUB_DISK_SECTOR_BITS,
- paddr & (GRUB_DISK_SECTOR_SIZE - 1),
- csize, buf);
- if (!err)
- break;
- grub_errno = GRUB_ERR_NONE;
+ err = btrfs_read_from_chunk (data, chunk, stripen,
+stripe_offset,
+i, /* redundancy */
+csize, buf);
+ if (err == GRUB_ERR_NONE)
+ break;
}
- if (i != redundancy)
- break;
+ if (err == GRUB_ERR_NONE)
+ break;
}
if (err)
return grub_errno = err;
--
2.17.0
___
Grub-devel mailing list
Grub-devel@gnu.org
https://lists.gnu.org/mailman/listinfo/grub-devel
[PATCH 3/9] btrfs: move the error logging from find_device() to its callee.
This is a preparatory patch. The callee knows better if this
error is fatal or not, i.e. another available disk.
Signed-off-by: Goffredo Baroncelli
---
grub-core/fs/btrfs.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/grub-core/fs/btrfs.c b/grub-core/fs/btrfs.c
index 123bfbfc1..fd4225d11 100644
--- a/grub-core/fs/btrfs.c
+++ b/grub-core/fs/btrfs.c
@@ -604,9 +604,6 @@ find_device (struct grub_btrfs_data *data, grub_uint64_t
id, int do_rescan)
grub_device_iterate (find_device_iter, &ctx);
if (!ctx.dev_found)
{
- grub_error (GRUB_ERR_BAD_FS,
- N_("couldn't find a necessary member device "
-"of multi-device filesystem"));
return NULL;
}
data->n_devices_attached++;
@@ -900,6 +897,9 @@ grub_btrfs_read_logical (struct grub_btrfs_data *data,
grub_disk_addr_t addr,
dev = find_device (data, stripe->device_id, j);
if (!dev)
{
+ grub_dprintf ("btrfs",
+ "couldn't find a necessary member device "
+ "of multi-device filesystem\n");
err = grub_errno;
grub_errno = GRUB_ERR_NONE;
continue;
--
2.17.0
___
Grub-devel mailing list
Grub-devel@gnu.org
https://lists.gnu.org/mailman/listinfo/grub-devel
[PATCH 4/9] btrfs: avoiding a rescan for a device which was already not founded.
If a device is not found, record this failure storing NULL in
data->devices_attached[]. This avoid un-necessary devices rescan,
speeding the reading in case of a degraded array.
Signed-off-by: Goffredo Baroncelli
---
grub-core/fs/btrfs.c | 19 +--
1 file changed, 9 insertions(+), 10 deletions(-)
diff --git a/grub-core/fs/btrfs.c b/grub-core/fs/btrfs.c
index fd4225d11..4920dd3b1 100644
--- a/grub-core/fs/btrfs.c
+++ b/grub-core/fs/btrfs.c
@@ -588,7 +588,7 @@ find_device_iter (const char *name, void *data)
}
static grub_device_t
-find_device (struct grub_btrfs_data *data, grub_uint64_t id, int do_rescan)
+find_device (struct grub_btrfs_data *data, grub_uint64_t id)
{
struct find_device_ctx ctx = {
.data = data,
@@ -600,12 +600,9 @@ find_device (struct grub_btrfs_data *data, grub_uint64_t
id, int do_rescan)
for (i = 0; i < data->n_devices_attached; i++)
if (id == data->devices_attached[i].id)
return data->devices_attached[i].dev;
- if (do_rescan)
-grub_device_iterate (find_device_iter, &ctx);
- if (!ctx.dev_found)
-{
- return NULL;
-}
+
+ grub_device_iterate (find_device_iter, &ctx);
+
data->n_devices_attached++;
if (data->n_devices_attached > data->n_devices_allocated)
{
@@ -617,7 +614,8 @@ find_device (struct grub_btrfs_data *data, grub_uint64_t
id, int do_rescan)
* sizeof (data->devices_attached[0]));
if (!data->devices_attached)
{
- grub_device_close (ctx.dev_found);
+ if (ctx.dev_found)
+ grub_device_close (ctx.dev_found);
data->devices_attached = tmp;
return NULL;
}
@@ -894,7 +892,7 @@ grub_btrfs_read_logical (struct grub_btrfs_data *data,
grub_disk_addr_t addr,
" for laddr 0x%" PRIxGRUB_UINT64_T "\n", paddr,
addr);
- dev = find_device (data, stripe->device_id, j);
+ dev = find_device (data, stripe->device_id);
if (!dev)
{
grub_dprintf ("btrfs",
@@ -971,7 +969,8 @@ grub_btrfs_unmount (struct grub_btrfs_data *data)
unsigned i;
/* The device 0 is closed one layer upper. */
for (i = 1; i < data->n_devices_attached; i++)
-grub_device_close (data->devices_attached[i].dev);
+if (data->devices_attached[i].dev)
+grub_device_close (data->devices_attached[i].dev);
grub_free (data->devices_attached);
grub_free (data->extent);
grub_free (data);
--
2.17.0
___
Grub-devel mailing list
Grub-devel@gnu.org
https://lists.gnu.org/mailman/listinfo/grub-devel
[PATCH 1/9] btrfs: add support for reading a filesystem with a RAID 5 or RAID 6 profile.
Signed-off-by: Goffredo Baroncelli
---
grub-core/fs/btrfs.c | 68
1 file changed, 68 insertions(+)
diff --git a/grub-core/fs/btrfs.c b/grub-core/fs/btrfs.c
index be195448d..394611cbb 100644
--- a/grub-core/fs/btrfs.c
+++ b/grub-core/fs/btrfs.c
@@ -119,6 +119,8 @@ struct grub_btrfs_chunk_item
#define GRUB_BTRFS_CHUNK_TYPE_RAID1 0x10
#define GRUB_BTRFS_CHUNK_TYPE_DUPLICATED0x20
#define GRUB_BTRFS_CHUNK_TYPE_RAID100x40
+#define GRUB_BTRFS_CHUNK_TYPE_RAID5 0x80
+#define GRUB_BTRFS_CHUNK_TYPE_RAID6 0x100
grub_uint8_t dummy2[0xc];
grub_uint16_t nstripes;
grub_uint16_t nsubstripes;
@@ -764,6 +766,72 @@ grub_btrfs_read_logical (struct grub_btrfs_data *data,
grub_disk_addr_t addr,
stripe_offset = low + chunk_stripe_length
* high;
csize = chunk_stripe_length - low;
+ break;
+ }
+ case GRUB_BTRFS_CHUNK_TYPE_RAID5:
+ case GRUB_BTRFS_CHUNK_TYPE_RAID6:
+ {
+ grub_uint64_t nparities, stripe_nr, high, low;
+
+ redundancy = 1; /* no redundancy for now */
+
+ if (grub_le_to_cpu64 (chunk->type) & GRUB_BTRFS_CHUNK_TYPE_RAID5)
+ {
+ grub_dprintf ("btrfs", "RAID5\n");
+ nparities = 1;
+ }
+ else
+ {
+ grub_dprintf ("btrfs", "RAID6\n");
+ nparities = 2;
+ }
+
+ /*
+ * Below an example of a RAID6 layout and the meaning of the
+ * variables. The same apply to RAID5. The only differences is
that
+ * there is only one parity instead of two.
+ *
+ * A RAID6 6 layout consists in several stripes spread
+ * on the disks, following a layout like the one below
+ *
+ * Disk1 Disk2 Disk3 Ddisk4
+ *
+ *A1 B1 P1 Q1
+ *Q2 A2 B2 P2
+ *P3 Q3 A3 B3
+ * [...]
+ *
+ * Note that the placement of the parities depends on row index;
+ * In the code below:
+ * stripe_nr -> is the stripe number not considering the parities
+ * (A1=0, B1=1, A2 = 2, B2 = 3, ...)
+ * high -> is the row number (0 for A1...Q1, 1 for Q2..P2, ...)
+ * stripen -> is the column number (or disk number)
+ * off -> logical address to read (from the beginning of the
+ * chunk space)
+ * chunk_stripe_length -> size of a stripe (typically 64k)
+ * nstripes -> number of disks
+ * low -> offset of the data inside a stripe
+ *
+ */
+ stripe_nr = grub_divmod64 (off, chunk_stripe_length, &low);
+
+ /*
+ * In the line below stripen is evaluated without considering
+ * the parities (0 for A1, A2, A3... 1 for B1, B2...);
+ */
+ high = grub_divmod64 (stripe_nr, nstripes - nparities, &stripen);
+
+ /*
+ * In the line below stripen, now consider also the parities (0
+ * for A1, 1 for A2, 2 for A3); the math is done "modulo"
+ * number of disks
+ */
+ grub_divmod64 (high + stripen, nstripes, &stripen);
+
+ stripe_offset = low + chunk_stripe_length * high;
+ csize = chunk_stripe_length - low;
+
break;
}
default:
--
2.17.0
___
Grub-devel mailing list
Grub-devel@gnu.org
https://lists.gnu.org/mailman/listinfo/grub-devel
[PATCH 7/9] btrfs: add support for recovery for a RAID 5 btrfs profiles.
Signed-off-by: Goffredo Baroncelli
---
grub-core/fs/btrfs.c | 174 ++-
1 file changed, 170 insertions(+), 4 deletions(-)
diff --git a/grub-core/fs/btrfs.c b/grub-core/fs/btrfs.c
index 63651928b..5fcaad86f 100644
--- a/grub-core/fs/btrfs.c
+++ b/grub-core/fs/btrfs.c
@@ -29,6 +29,7 @@
#include
#include
#include
+#include
GRUB_MOD_LICENSE ("GPLv3+");
@@ -666,6 +667,150 @@ btrfs_read_from_chunk (struct grub_btrfs_data *data,
return err;
}
+struct raid56_buffer {
+ void *buf;
+ int data_is_valid;
+};
+
+static void
+rebuild_raid5 (struct raid56_buffer *buffers, grub_uint64_t nstripes,
+ grub_uint64_t csize)
+{
+ grub_uint64_t target = 0, i;
+
+ while (buffers[target].data_is_valid && target < nstripes)
+++target;
+
+ if (target == nstripes)
+{
+ grub_dprintf ("btrfs", "called rebuild_raid5(), but all disks are OK\n");
+ return;
+}
+
+ grub_dprintf ("btrfs", "rebuilding raid5 stripe #%" PRIuGRUB_UINT64_T "\n",
+ target);
+ for (i = 0; i < nstripes; i++)
+if (i != target)
+ grub_crypto_xor (buffers[target].buf, buffers[target].buf,
buffers[i].buf,
+ csize);
+}
+
+static grub_err_t
+raid56_read_retry (struct grub_btrfs_data *data,
+ struct grub_btrfs_chunk_item *chunk,
+ grub_uint64_t stripe_offset, grub_uint64_t stripen,
+ grub_uint64_t csize, void *buf)
+{
+
+ struct raid56_buffer *buffers = NULL;
+ grub_uint64_t nstripes = grub_le_to_cpu16 (chunk->nstripes);
+ grub_uint64_t chunk_type = grub_le_to_cpu64 (chunk->type);
+ grub_err_t ret = GRUB_ERR_NONE;
+ grub_uint64_t i, failed_devices;
+
+ buffers = grub_zalloc (sizeof(*buffers) * nstripes);
+ if (!buffers)
+{
+ ret = GRUB_ERR_OUT_OF_MEMORY;
+ goto cleanup;
+}
+
+ for (i = 0; i < nstripes; i++)
+{
+ buffers[i].buf = grub_zalloc (csize);
+ if (!buffers[i].buf)
+ {
+ ret = GRUB_ERR_OUT_OF_MEMORY;
+ goto cleanup;
+ }
+}
+
+ for (i = 0; i < nstripes; i++)
+{
+ struct grub_btrfs_chunk_stripe *stripe;
+ grub_disk_addr_t paddr;
+ grub_device_t dev;
+ grub_err_t err2;
+
+ stripe = (struct grub_btrfs_chunk_stripe *) (chunk + 1);
+ stripe += i;
+
+ paddr = grub_le_to_cpu64 (stripe->offset) + stripe_offset;
+ grub_dprintf ("btrfs", "reading paddr %" PRIxGRUB_UINT64_T
+" from stripe ID %" PRIxGRUB_UINT64_T "\n", paddr,
+stripe->device_id);
+
+ dev = find_device (data, stripe->device_id);
+ if (!dev)
+ {
+ buffers[i].data_is_valid = 0;
+ grub_dprintf ("btrfs", "stripe %" PRIuGRUB_UINT64_T " FAILED (dev ID
%"
+ PRIxGRUB_UINT64_T ")\n", i, stripe->device_id);
+ continue;
+ }
+
+ err2 = grub_disk_read (dev->disk, paddr >> GRUB_DISK_SECTOR_BITS,
+paddr & (GRUB_DISK_SECTOR_SIZE - 1),
+csize, buffers[i].buf);
+ if (err2 == GRUB_ERR_NONE)
+ {
+ buffers[i].data_is_valid = 1;
+ grub_dprintf ("btrfs", "stripe %" PRIuGRUB_UINT64_T " Ok (dev ID %"
+ PRIxGRUB_UINT64_T ")\n", i, stripe->device_id);
+ }
+ else
+ {
+ buffers[i].data_is_valid = 0;
+ grub_dprintf ("btrfs", "stripe %" PRIuGRUB_UINT64_T
+ " FAILED (dev ID %" PRIxGRUB_UINT64_T ")\n", i,
+ stripe->device_id);
+ }
+}
+
+ failed_devices = 0;
+ for (i = 0; i < nstripes; i++)
+if (!buffers[i].data_is_valid)
+ ++failed_devices;
+ if (failed_devices > 1 && (chunk_type & GRUB_BTRFS_CHUNK_TYPE_RAID5))
+{
+ grub_dprintf ("btrfs",
+ "not enough disks for raid5: total %" PRIuGRUB_UINT64_T
+ ", missing %" PRIuGRUB_UINT64_T "\n",
+ nstripes, failed_devices);
+ ret = GRUB_ERR_READ_ERROR;
+ goto cleanup;
+}
+ else
+{
+ grub_dprintf ("btrfs",
+"enough disks for raid5/6 rebuilding: total %"
+ PRIuGRUB_UINT64_T ", missing %" PRIuGRUB_UINT64_T "\n",
+nstripes, failed_devices);
+}
+
+ /* if these are enough, try to rebuild the data */
+ if (chunk_type & GRUB_BTRFS_CHUNK_TYPE_RAID5)
+{
+ rebuild_raid5 (buffers, nstripes, csize);
+ grub_memcpy (buf, buffers[stripen].buf, csize);
+}
+ else
+{
+ grub_dprintf ("btrfs", "called rebuild_raid6(), NOT IMPLEMENTED\n");
+}
+
+cleanup:
+ if (buffers)
+{
+ for (i = 0; i < nstripes; i++)
+ if (buffers[i].buf)
+ grub_free(buffers[i].buf);
+ grub_free(buffers);
+}
+
+ return ret;
+}
+
static grub_err_t
grub_btrfs_read_logical (struct grub_btrfs_data *data, grub_disk_addr_t addr,
void *buf, grub_size_t size, int recursion_depth)
@@ -743,6 +888,11 @@
[PATCH 9/9] btrfs: add RAID 6 recovery for a btrfs filesystem.
Add the RAID 6 recovery, in order to use a RAID 6 filesystem even if some
disks (up to two) are missing. This code use the old md RAID 6 code already
present in grub.
Signed-off-by: Goffredo Baroncelli
---
grub-core/fs/btrfs.c | 45 +++-
1 file changed, 40 insertions(+), 5 deletions(-)
diff --git a/grub-core/fs/btrfs.c b/grub-core/fs/btrfs.c
index 5fcaad86f..3d71b954e 100644
--- a/grub-core/fs/btrfs.c
+++ b/grub-core/fs/btrfs.c
@@ -30,6 +30,7 @@
#include
#include
#include
+#include
GRUB_MOD_LICENSE ("GPLv3+");
@@ -695,11 +696,35 @@ rebuild_raid5 (struct raid56_buffer *buffers,
grub_uint64_t nstripes,
csize);
}
+static grub_err_t
+raid6_recover_read_buffer (void *data, int disk_nr,
+ grub_uint64_t addr __attribute__ ((unused)),
+ void *dest, grub_size_t size)
+{
+struct raid56_buffer *buffers = data;
+
+grub_memcpy(dest, buffers[disk_nr].buf, size);
+
+grub_errno = buffers[disk_nr].data_is_valid ? GRUB_ERR_NONE :
+GRUB_ERR_READ_ERROR;
+return grub_errno;
+}
+
+static void
+rebuild_raid6 (struct raid56_buffer *buffers, grub_uint64_t nstripes,
+ grub_uint64_t csize, grub_uint64_t parities_pos, void *dest,
+ grub_uint64_t stripen)
+
+{
+ grub_raid6_recover_gen (buffers, nstripes, stripen, parities_pos,
+ dest, 0, csize, raid6_recover_read_buffer, 0);
+}
+
static grub_err_t
raid56_read_retry (struct grub_btrfs_data *data,
struct grub_btrfs_chunk_item *chunk,
grub_uint64_t stripe_offset, grub_uint64_t stripen,
- grub_uint64_t csize, void *buf)
+ grub_uint64_t csize, void *buf, grub_uint64_t parities_pos)
{
struct raid56_buffer *buffers = NULL;
@@ -780,6 +805,15 @@ raid56_read_retry (struct grub_btrfs_data *data,
ret = GRUB_ERR_READ_ERROR;
goto cleanup;
}
+ else if (failed_devices > 2 && (chunk_type & GRUB_BTRFS_CHUNK_TYPE_RAID6))
+{
+ grub_dprintf ("btrfs",
+ "not enough disks for raid6: total %" PRIuGRUB_UINT64_T
+ ", missing %" PRIuGRUB_UINT64_T "\n",
+ nstripes, failed_devices);
+ ret = GRUB_ERR_READ_ERROR;
+ goto cleanup;
+}
else
{
grub_dprintf ("btrfs",
@@ -796,7 +830,7 @@ raid56_read_retry (struct grub_btrfs_data *data,
}
else
{
- grub_dprintf ("btrfs", "called rebuild_raid6(), NOT IMPLEMENTED\n");
+ rebuild_raid6 (buffers, nstripes, csize, parities_pos, buf, stripen);
}
cleanup:
@@ -891,8 +925,9 @@ grub_btrfs_read_logical (struct grub_btrfs_data *data,
grub_disk_addr_t addr,
int is_raid56;
grub_uint64_t parities_pos = 0;
- is_raid56 = !!(grub_le_to_cpu64 (chunk->type) &
- GRUB_BTRFS_CHUNK_TYPE_RAID5);
+is_raid56 = !!(grub_le_to_cpu64 (chunk->type) &
+ (GRUB_BTRFS_CHUNK_TYPE_RAID5|
+ GRUB_BTRFS_CHUNK_TYPE_RAID6));
if (grub_le_to_cpu64 (chunk->size) <= off)
{
@@ -1089,7 +1124,7 @@ grub_btrfs_read_logical (struct grub_btrfs_data *data,
grub_disk_addr_t addr,
csize, buf);
if (err != GRUB_ERR_NONE)
err = raid56_read_retry (data, chunk, stripe_offset,
- stripen, csize, buf);
+ stripen, csize, buf, parities_pos);
}
if (err == GRUB_ERR_NONE)
--
2.17.0
___
Grub-devel mailing list
Grub-devel@gnu.org
https://lists.gnu.org/mailman/listinfo/grub-devel
[PATCH V4] Add support for BTRFS raid5/6 to GRUB
Hi All, the aim of this patches set is to provide support for a BTRFS raid5/6 filesystem in GRUB. The first patch, implements the basic support for raid5/6. I.e this works when all the disks are present. The next 5 patches, are preparatory ones. The 7th patch implements the raid5 recovery for btrfs (i.e. handling the disappearing of 1 disk). The 8th patch makes the code for handling the raid6 recovery more generic. The last one implements the raid6 recovery for btrfs (i.e. handling the disappearing up to two disks). I tested the code in grub-emu, and it works (for me) both with all the disks, and with some disks missing. I checked the crc32 calculated from grub and from linux and these matched. Finally I checked if the support for md raid6 still works properly, and it does (with all the drives and with up to 2 drives missing) Comments are welcome. Changelog v1: initial support for btrfs raid5/6. No recovery allowed v2: full support for btrfs raid5/6. Recovery allowed v3: some minor cleanup suggested by Daniel Kiper; reusing the original raid6 recovery code of grub v4: Several spell fix; better description of the RAID layout in btrfs, and the variables which describes the stripe positioning; split the patch #5 in two (#5 and #6) BR G.Baroncelli-- gpg @keyserver.linux.it: Goffredo Baroncelli Key fingerprint BBF5 1610 0B64 DAC6 5F7D 17B2 0EDA 9B37 8B82 E0B5 ___ Grub-devel mailing list Grub-devel@gnu.org https://lists.gnu.org/mailman/listinfo/grub-devel
[PATCH 8/9] btrfs: make more generic the code for RAID 6 rebuilding
The original code which handles the recovery of a RAID 6 disks array
assumes that all reads are multiple of 1 << GRUB_DISK_SECTOR_BITS and it
assumes that all the I/O is done via the struct grub_diskfilter_segment.
This is not true for the btrfs code. In order to reuse the native
grub_raid6_recover() code, it is modified to not call
grub_diskfilter_read_node() directly, but to call an handler passed
as argument.
Signed-off-by: Goffredo Baroncelli
---
grub-core/disk/raid6_recover.c | 53 ++
include/grub/diskfilter.h | 9 ++
2 files changed, 44 insertions(+), 18 deletions(-)
diff --git a/grub-core/disk/raid6_recover.c b/grub-core/disk/raid6_recover.c
index aa674f6ca..10ee495e2 100644
--- a/grub-core/disk/raid6_recover.c
+++ b/grub-core/disk/raid6_recover.c
@@ -74,14 +74,25 @@ mod_255 (unsigned x)
}
static grub_err_t
-grub_raid6_recover (struct grub_diskfilter_segment *array, int disknr, int p,
-char *buf, grub_disk_addr_t sector, grub_size_t size)
+raid6_recover_read_node (void *data, int disk_nr,
+ grub_uint64_t sector,
+ void *buf, grub_size_t size)
+{
+struct grub_diskfilter_segment *array = data;
+return grub_diskfilter_read_node (&array->nodes[disk_nr],
+ (grub_disk_addr_t)sector,
+ size >> GRUB_DISK_SECTOR_BITS, buf);
+}
+
+grub_err_t
+grub_raid6_recover_gen (void *data, grub_uint64_t nstripes, int disknr, int p,
+ char *buf, grub_uint64_t sector, grub_size_t size,
+ raid_recover_read_t read_func, int layout)
{
int i, q, pos;
int bad1 = -1, bad2 = -1;
char *pbuf = 0, *qbuf = 0;
- size <<= GRUB_DISK_SECTOR_BITS;
pbuf = grub_zalloc (size);
if (!pbuf)
goto quit;
@@ -91,17 +102,17 @@ grub_raid6_recover (struct grub_diskfilter_segment *array,
int disknr, int p,
goto quit;
q = p + 1;
- if (q == (int) array->node_count)
+ if (q == (int) nstripes)
q = 0;
pos = q + 1;
- if (pos == (int) array->node_count)
+ if (pos == (int) nstripes)
pos = 0;
- for (i = 0; i < (int) array->node_count - 2; i++)
+ for (i = 0; i < (int) nstripes - 2; i++)
{
int c;
- if (array->layout & GRUB_RAID_LAYOUT_MUL_FROM_POS)
+ if (layout & GRUB_RAID_LAYOUT_MUL_FROM_POS)
c = pos;
else
c = i;
@@ -109,8 +120,7 @@ grub_raid6_recover (struct grub_diskfilter_segment *array,
int disknr, int p,
bad1 = c;
else
{
- if (! grub_diskfilter_read_node (&array->nodes[pos], sector,
- size >> GRUB_DISK_SECTOR_BITS, buf))
+ if (!read_func(data, pos, sector, buf, size))
{
grub_crypto_xor (pbuf, pbuf, buf, size);
grub_raid_block_mulx (c, buf, size);
@@ -128,7 +138,7 @@ grub_raid6_recover (struct grub_diskfilter_segment *array,
int disknr, int p,
}
pos++;
- if (pos == (int) array->node_count)
+ if (pos == (int) nstripes)
pos = 0;
}
@@ -139,16 +149,14 @@ grub_raid6_recover (struct grub_diskfilter_segment
*array, int disknr, int p,
if (bad2 < 0)
{
/* One bad device */
- if ((! grub_diskfilter_read_node (&array->nodes[p], sector,
- size >> GRUB_DISK_SECTOR_BITS, buf)))
+ if (!read_func(data, p, sector, buf, size))
{
grub_crypto_xor (buf, buf, pbuf, size);
goto quit;
}
grub_errno = GRUB_ERR_NONE;
- if (grub_diskfilter_read_node (&array->nodes[q], sector,
-size >> GRUB_DISK_SECTOR_BITS, buf))
+ if (read_func(data, q, sector, buf, size))
goto quit;
grub_crypto_xor (buf, buf, qbuf, size);
@@ -160,14 +168,12 @@ grub_raid6_recover (struct grub_diskfilter_segment
*array, int disknr, int p,
/* Two bad devices */
unsigned c;
- if (grub_diskfilter_read_node (&array->nodes[p], sector,
-size >> GRUB_DISK_SECTOR_BITS, buf))
+ if (read_func(data, p, sector, buf, size))
goto quit;
grub_crypto_xor (pbuf, pbuf, buf, size);
- if (grub_diskfilter_read_node (&array->nodes[q], sector,
-size >> GRUB_DISK_SECTOR_BITS, buf))
+ if (read_func(data, q, sector, buf, size))
goto quit;
grub_crypto_xor (qbuf, qbuf, buf, size);
@@ -190,6 +196,17 @@ quit:
return grub_errno;
}
+static grub_err_t
+grub_raid6_recover (struct grub_diskfilter_segment *array, int disknr, int p,
+char *buf, grub_disk_addr_t sector, grub_size_t size)
+{
+
+ return grub_raid6_recover_gen (array, array->node_count, disknr, p, buf,
+sector, size << GRUB_DISK_SECTOR_BITS,
+ra
Re: [PATCH 6/8] Add support for recovery for a raid5 btrfs profiles.
On 05/14/2018 08:40 PM, Daniel Kiper wrote:
> On Fri, May 11, 2018 at 09:24:44PM +0200, Goffredo Baroncelli wrote:
>> Signed-off-by: Goffredo Baroncelli
>> ---
>> grub-core/fs/btrfs.c | 178 +--
>> 1 file changed, 173 insertions(+), 5 deletions(-)
>>
>> diff --git a/grub-core/fs/btrfs.c b/grub-core/fs/btrfs.c
>> index fc4198e39..8d72607d1 100644
>> --- a/grub-core/fs/btrfs.c
>> +++ b/grub-core/fs/btrfs.c
>> @@ -29,6 +29,7 @@
>> #include
>> #include
>> #include
>> +#include
>>
>> GRUB_MOD_LICENSE ("GPLv3+");
>>
>> @@ -663,9 +664,156 @@ btrfs_read_from_chunk (struct grub_btrfs_data *data,
>> err = grub_disk_read (dev->disk, paddr >> GRUB_DISK_SECTOR_BITS,
>>paddr & (GRUB_DISK_SECTOR_SIZE - 1),
>>csize, buf);
>> +grub_dprintf ("btrfs", "reading paddr 0x%" PRIxGRUB_UINT64_T "\n",
>> paddr);
>> return err;
>> }
>>
>> +struct raid56_buffer {
>> + void *buf;
>> + int data_is_valid;
>> +};
>> +
>> +static void
>> +rebuild_raid5 (struct raid56_buffer *buffers, grub_uint64_t nstripes,
>> + grub_uint64_t csize)
>> +{
>> + grub_uint64_t target = 0, i;
>> +
>> + while (buffers[target].data_is_valid && target < nstripes)
>> +++target;
>> +
>> + if (target == nstripes)
>> +{
>> + grub_dprintf ("btrfs", "called rebuild_raid5(), but all disks are
>> OK\n");
>> + return;
>> +}
>> +
>> + grub_dprintf ("btrfs", "rebuilding raid5 stripe #%" PRIuGRUB_UINT64_T
>> "\n",
>> +target);
>> + for (i = 0; i < nstripes ; i++)
>
> Please drop extra space behind nstripes. I have found
> similar issues below too. Please fix all of them.
>
>> +if (i != target)
>> + grub_crypto_xor (buffers[target].buf, buffers[target].buf,
>> buffers[i].buf,
>> + csize);
>> +}
>> +
>> +static grub_err_t
>> +raid56_read_retry (struct grub_btrfs_data *data,
>> + struct grub_btrfs_chunk_item *chunk,
>> + grub_uint64_t stripe_offset, grub_uint64_t stripen,
>> + grub_uint64_t csize, void *buf)
>> +{
>> +
>> + struct raid56_buffer *buffers = NULL;
>> + grub_uint64_t nstripes = grub_le_to_cpu16 (chunk->nstripes);
>> + grub_uint64_t chunk_type = grub_le_to_cpu64 (chunk->type);
>> + grub_err_t ret = GRUB_ERR_NONE;
>> + grub_uint64_t i, failed_devices;
>> +
>> + buffers = grub_zalloc (sizeof(*buffers) * nstripes);
>> + if (!buffers)
>> +{
>> + ret = GRUB_ERR_OUT_OF_MEMORY;
>> + goto cleanup;
>> +}
>> +
>> + for (i = 0; i < nstripes ; i++)
>
> Ditto.
>
>> +{
>> + buffers[i].buf = grub_zalloc (csize);
>> + if (!buffers[i].buf)
>> +{
>> + ret = GRUB_ERR_OUT_OF_MEMORY;
>> + goto cleanup;
>> +}
>> +}
>> +
>> + for (i = 0; i < nstripes ; i++)
>
> Ditto.
>
>> +{
>> + struct grub_btrfs_chunk_stripe *stripe;
>> + grub_disk_addr_t paddr;
>> + grub_device_t dev;
>> + grub_err_t err2;
>> +
>> + stripe = (struct grub_btrfs_chunk_stripe *) (chunk + 1);
>> + stripe += i;
>> +
>> + paddr = grub_le_to_cpu64 (stripe->offset) + stripe_offset;
>> + grub_dprintf ("btrfs", "reading paddr %" PRIxGRUB_UINT64_T
>> +" from stripe ID %" PRIxGRUB_UINT64_T "\n", paddr,
>> +stripe->device_id);
>> +
>> + /* FIXME: rescan the devices */
>
> Could you be more verbose here?
This was an initial comment. After few thoughts I concluded that it was wrong.
So I
removed it in the next patches set.
>
>> + dev = find_device (data, stripe->device_id);
>> + if (!dev)
>> +{
>> + buffers[i].data_is_valid = 0;
>> + grub_dprintf ("btrfs", "stripe %" PRIuGRUB_UINT64_T " FAILED (dev ID
>> %"
>> +PRIxGRUB_UINT64_T ")\n", i, stripe->device_id);
>> + continue;
>> +}
>> +
>> + err2 = grub_disk_read (dev->disk, paddr >> GRUB_DISK_SECTOR_BITS,
>> + paddr & (GRUB_DISK_SECTOR_SIZE - 1),
>> + csize, buffers[i].buf);
>> + if (err2 == GRUB_ERR_NONE)
>> +{
>> + buffers[i].data_is_valid = 1;
>> + grub_dprintf ("btrfs", "stripe %" PRIuGRUB_UINT64_T " Ok (dev ID %"
>> +PRIxGRUB_UINT64_T ")\n", i, stripe->device_id);
>> +}
>> + else
>> +{
>> + buffers[i].data_is_valid = 0;
>> + grub_dprintf ("btrfs", "stripe %" PRIuGRUB_UINT64_T
>> +" FAILED (dev ID %" PRIxGRUB_UINT64_T ")\n", i,
>> +stripe->device_id);
>> +}
>> +}
>> +
>> + failed_devices = 0;
>> + for (i = 0; i < nstripes ; i++)
>> +if (!buffers[i].data_is_valid)
>> + ++failed_devices;
>> + if (failed_devices > 1 && (chunk_type & GRUB_BTRFS_CHUNK_TYPE_RAID5))
>> +{
>> + grub_dprintf ("btrfs",
>> +"not enough disks for raid5: total %" PRIuGRUB_UINT64_T
>> +", missing %" PRIuGRUB_UINT64_T "\n",
>> +n
[PATCH 2/9] btrfs: add helper to check the btrfs header.
This helper will be used in few places to help the debugging. As
conservative approach, in case of error it is only logged. This
because I am not sure if this can change something in the error
handling of the currently existing code.
Signed-off-by: Goffredo Baroncelli
---
grub-core/fs/btrfs.c | 24 +++-
1 file changed, 23 insertions(+), 1 deletion(-)
diff --git a/grub-core/fs/btrfs.c b/grub-core/fs/btrfs.c
index 394611cbb..123bfbfc1 100644
--- a/grub-core/fs/btrfs.c
+++ b/grub-core/fs/btrfs.c
@@ -77,7 +77,8 @@ struct btrfs_header
{
grub_btrfs_checksum_t checksum;
grub_btrfs_uuid_t uuid;
- grub_uint8_t dummy[0x30];
+ grub_uint64_t bytenr;
+ grub_uint8_t dummy[0x28];
grub_uint32_t nitems;
grub_uint8_t level;
} GRUB_PACKED;
@@ -286,6 +287,25 @@ free_iterator (struct grub_btrfs_leaf_descriptor *desc)
grub_free (desc->data);
}
+static grub_err_t
+check_btrfs_header (struct grub_btrfs_data *data, struct btrfs_header *header,
+grub_disk_addr_t addr)
+{
+ if (grub_le_to_cpu64 (header->bytenr) != addr)
+{
+ grub_dprintf ("btrfs", "btrfs_header.bytenr is not equal node addr\n");
+ return grub_error (GRUB_ERR_BAD_FS,
+"header bytenr is not equal node addr");
+}
+ if (grub_memcmp (data->sblock.uuid, header->uuid, sizeof(grub_btrfs_uuid_t)))
+{
+ grub_dprintf ("btrfs", "btrfs_header.uuid doesn't match sblock uuid\n");
+ return grub_error (GRUB_ERR_BAD_FS,
+"header uuid doesn't match sblock uuid");
+}
+ return GRUB_ERR_NONE;
+}
+
static grub_err_t
save_ref (struct grub_btrfs_leaf_descriptor *desc,
grub_disk_addr_t addr, unsigned i, unsigned m, int l)
@@ -341,6 +361,7 @@ next (struct grub_btrfs_data *data,
err = grub_btrfs_read_logical (data, grub_le_to_cpu64 (node.addr),
&head, sizeof (head), 0);
+ check_btrfs_header (data, &head, grub_le_to_cpu64 (node.addr));
if (err)
return -err;
@@ -402,6 +423,7 @@ lower_bound (struct grub_btrfs_data *data,
/* FIXME: preread few nodes into buffer. */
err = grub_btrfs_read_logical (data, addr, &head, sizeof (head),
recursion_depth + 1);
+ check_btrfs_header (data, &head, addr);
if (err)
return err;
addr += sizeof (head);
--
2.17.0
___
Grub-devel mailing list
Grub-devel@gnu.org
https://lists.gnu.org/mailman/listinfo/grub-devel
[PATCH 5/9] btrfs: move logging code in grub_btrfs_read_logical()
A portion of the logging code is moved outside a for(;;). The part that is
left inside is the one which depends by the for(;;) index.
This is a preparatory patch: in the next one it will be possible to refactor
the code inside the for(;;) in an another function.
---
grub-core/fs/btrfs.c | 25 ++---
1 file changed, 14 insertions(+), 11 deletions(-)
diff --git a/grub-core/fs/btrfs.c b/grub-core/fs/btrfs.c
index 4920dd3b1..51f300829 100644
--- a/grub-core/fs/btrfs.c
+++ b/grub-core/fs/btrfs.c
@@ -865,6 +865,18 @@ grub_btrfs_read_logical (struct grub_btrfs_data *data,
grub_disk_addr_t addr,
for (j = 0; j < 2; j++)
{
+ grub_dprintf ("btrfs", "chunk 0x%" PRIxGRUB_UINT64_T
+ "+0x%" PRIxGRUB_UINT64_T
+ " (%d stripes (%d substripes) of %"
+ PRIxGRUB_UINT64_T ") \n",
+ grub_le_to_cpu64 (key->offset),
+ grub_le_to_cpu64 (chunk->size),
+ grub_le_to_cpu16 (chunk->nstripes),
+ grub_le_to_cpu16 (chunk->nsubstripes),
+ grub_le_to_cpu64 (chunk->stripe_length));
+ grub_dprintf ("btrfs", "reading laddr 0x%" PRIxGRUB_UINT64_T "\n",
+ addr);
+
for (i = 0; i < redundancy; i++)
{
struct grub_btrfs_chunk_stripe *stripe;
@@ -877,20 +889,11 @@ grub_btrfs_read_logical (struct grub_btrfs_data *data,
grub_disk_addr_t addr,
paddr = grub_le_to_cpu64 (stripe->offset) + stripe_offset;
- grub_dprintf ("btrfs", "chunk 0x%" PRIxGRUB_UINT64_T
- "+0x%" PRIxGRUB_UINT64_T
- " (%d stripes (%d substripes) of %"
- PRIxGRUB_UINT64_T ") stripe %" PRIxGRUB_UINT64_T
+ grub_dprintf ("btrfs", "stripe %" PRIxGRUB_UINT64_T
" maps to 0x%" PRIxGRUB_UINT64_T "\n",
- grub_le_to_cpu64 (key->offset),
- grub_le_to_cpu64 (chunk->size),
- grub_le_to_cpu16 (chunk->nstripes),
- grub_le_to_cpu16 (chunk->nsubstripes),
- grub_le_to_cpu64 (chunk->stripe_length),
stripen, stripe->offset);
grub_dprintf ("btrfs", "reading paddr 0x%" PRIxGRUB_UINT64_T
- " for laddr 0x%" PRIxGRUB_UINT64_T "\n", paddr,
- addr);
+ "\n", paddr);
dev = find_device (data, stripe->device_id);
if (!dev)
--
2.17.0
___
Grub-devel mailing list
Grub-devel@gnu.org
https://lists.gnu.org/mailman/listinfo/grub-devel
Re: [PATCH 8/8] Add raid6 recovery for a btrfs filesystem.
On 05/14/2018 09:06 PM, Daniel Kiper wrote:
> On Fri, May 11, 2018 at 09:24:46PM +0200, Goffredo Baroncelli wrote:
>> Add the raid6 recovery, in order to use a raid6 filesystem even if some
>> disks (up to two) are missing.
>> This code use the old md raid6 code already present in grub.
>
> Please fix the commit message formating.
>
>> Signed-off-by: Goffredo Baroncelli
>> ---
>> grub-core/fs/btrfs.c | 43 +++
>> 1 file changed, 39 insertions(+), 4 deletions(-)
>>
>> diff --git a/grub-core/fs/btrfs.c b/grub-core/fs/btrfs.c
>> index 8d72607d1..07e9db910 100644
>> --- a/grub-core/fs/btrfs.c
>> +++ b/grub-core/fs/btrfs.c
>> @@ -30,6 +30,7 @@
>> #include
>> #include
>> #include
>> +#include
>>
>> GRUB_MOD_LICENSE ("GPLv3+");
>>
>> @@ -696,11 +697,36 @@ rebuild_raid5 (struct raid56_buffer *buffers,
>> grub_uint64_t nstripes,
>> csize);
>> }
>>
>> +static grub_err_t
>> +raid_recover_read_raid56_buffer (void *data, int disk_nr, grub_uint64_t
>> addr,
>> + void *dest, grub_size_t size)
>
> s/raid_recover_read_raid56_buffer/raid6_recover_read_node/
I renamed this as raid6_recover_read_buffer
It is not a node, because it is different handler than the one of patch #7
>
>> +{
>> +struct raid56_buffer *buffers = data;
>> +
>> +(void)addr;
>
> I do not like this. grub_uint64_t addr __attribute__ ((unused))" in
> prototype definition please.
>
>> +grub_memcpy(dest, buffers[disk_nr].buf, size);
>> +
>> +grub_errno = buffers[disk_nr].data_is_valid ? GRUB_ERR_NONE :
>> + GRUB_ERR_READ_ERROR;
>> +return grub_errno;
>> +}
>> +
>> +static void
>> +rebuild_raid6 (struct raid56_buffer *buffers, grub_uint64_t nstripes,
>> + grub_uint64_t csize, grub_uint64_t parities_pos, void *dest,
>> + grub_uint64_t stripen)
>
> struct as a argument?
I thought a bit about that; however I think that the there too few place where
grub_raid6_recover_gen() is called, so my feeling is that the effort is more
than the gain.
>
>> +
>> +{
>> + grub_raid6_recover_generic (buffers, nstripes, stripen, parities_pos,
>> + dest, 0, csize,
>> + raid_recover_read_raid56_buffer, 0);
>> +}
>> +
>> static grub_err_t
>> raid56_read_retry (struct grub_btrfs_data *data,
>> struct grub_btrfs_chunk_item *chunk,
>> grub_uint64_t stripe_offset, grub_uint64_t stripen,
>> - grub_uint64_t csize, void *buf)
>> + grub_uint64_t csize, void *buf, grub_uint64_t parities_pos)
>
> struct as a argument?
>
> Daniel
>
> ___
> Grub-devel mailing list
> Grub-devel@gnu.org
> https://lists.gnu.org/mailman/listinfo/grub-devel
>
--
gpg @keyserver.linux.it: Goffredo Baroncelli
Key fingerprint BBF5 1610 0B64 DAC6 5F7D 17B2 0EDA 9B37 8B82 E0B5
___
Grub-devel mailing list
Grub-devel@gnu.org
https://lists.gnu.org/mailman/listinfo/grub-devel
Re: [PATCH 1/8] Add support for reading a filesystem with a raid5 or raid6 profile.
On 05/14/2018 07:52 PM, Daniel Kiper wrote:
> On Fri, May 11, 2018 at 09:24:39PM +0200, Goffredo Baroncelli wrote:
>> Signed-off-by: Goffredo Baroncelli
>> ---
>> grub-core/fs/btrfs.c | 61
>> 1 file changed, 61 insertions(+)
>>
>> diff --git a/grub-core/fs/btrfs.c b/grub-core/fs/btrfs.c
>> index be195448d..7e287d0ec 100644
>> --- a/grub-core/fs/btrfs.c
>> +++ b/grub-core/fs/btrfs.c
>> @@ -119,6 +119,8 @@ struct grub_btrfs_chunk_item
>> #define GRUB_BTRFS_CHUNK_TYPE_RAID1 0x10
>> #define GRUB_BTRFS_CHUNK_TYPE_DUPLICATED0x20
>> #define GRUB_BTRFS_CHUNK_TYPE_RAID100x40
>> +#define GRUB_BTRFS_CHUNK_TYPE_RAID5 0x80
>> +#define GRUB_BTRFS_CHUNK_TYPE_RAID6 0x100
>>grub_uint8_t dummy2[0xc];
>>grub_uint16_t nstripes;
>>grub_uint16_t nsubstripes;
>> @@ -764,6 +766,65 @@ grub_btrfs_read_logical (struct grub_btrfs_data *data,
>> grub_disk_addr_t addr,
>>stripe_offset = low + chunk_stripe_length
>> * high;
>>csize = chunk_stripe_length - low;
>> + break;
>> +}
>> + case GRUB_BTRFS_CHUNK_TYPE_RAID5:
>> + case GRUB_BTRFS_CHUNK_TYPE_RAID6:
>> +{
>> + grub_uint64_t nparities, stripe_nr, high, low;
>> +
>> + redundancy = 1; /* no redundancy for now */
>> +
>> + if (grub_le_to_cpu64 (chunk->type) & GRUB_BTRFS_CHUNK_TYPE_RAID5)
>> +{
>> + grub_dprintf ("btrfs", "RAID5\n");
>> + nparities = 1;
>> +}
>> + else
>> +{
>> + grub_dprintf ("btrfs", "RAID6\n");
>> + nparities = 2;
>> +}
>> +
>> + /*
>> + * A raid 6 layout consists in several stripes spread
>
> This line is confusing if you compare it with both cases a few lines above.
> I think that you should explain somewhere why this math works for RAID 5
> and RAID 6.
>
>> + * on the disks, following a layout like the one below
>> + *
>> + * Disk1 Disk2 Disk3 Ddisk4
>> + *
>> + *A1 B1 P1 Q1
>> + *Q2 A2 B2 P2
>> + *P3 Q3 A3 B3
>> + * [...]
>> + *
>> + * Note that the placement of the parities depends by the row
>
> s/by the/on/?
>
>> + * index;
>> + * In the code below:
>> + * stripe_nr -> is the stripe number not considering the parities
>> + * (A1=0, B1=1, A2 = 2, B2 = 3, ...)
>> + * high -> is the row number (0 for A1...Q1, 1 for Q2..P2, ...)
>> + * stripen -> is the column number (or number of disk)
>
> s/number of disk/number of disk in row/?
>
>> + * off -> logical address to read (from teh beginning of the
>
> What is "teh"? nth? And it seems to me that off is the offset from the
> beginning of the array.
>
>> + * chunk space)
>
> I am not sure what you mean by "chunk space" here.
In BTRFS the logical space where are stored the data and the metadata is
divided in chunks (or block group). Each chunk maps its "logical space" to the
disk(s) space; how this "logical space" is arranged on the disk(s) depends by
the chunk profile. Eg:
- RAID1: the logical space is mapped on two disks, where each disk is the mirror
of the other.
- RAID5: the logical space is mapped on (n-1) disks, and the Nth disk is used
as parity (where n is the number of available disks).
Each chunks maps a logical space that has a size of few GB. This means that
a btrfs filesystem has several chunks. And each chunks may have different
profiles.
So it is possible that inside a btrfs filesystem there are area where a RAID1
profile is applied, other where a RAID5 is applied and so on...
>
>> + * chunk_stripe_length -> size of a stripe (typically 64k)
>
> I assume that stripe does not cover P1 and Q1 (parity disks)?
a stripe is a slice of a "row" (e.g. A1, B2, Q3...)
>
>> + * nstripes -> number of disks
>> + *
>> + */
>> + stripe_nr = grub_divmod64 (off, chunk_stripe_length, &low);
>
> What is the low?
"low", is the offset where the data is placed inside a "stripe"
>
>> + high = grub_divmod64 (stripe_nr, nstripes - nparities, &stripen);
>> +
>> + /*
>> + * until now stripen is evaluated without the parities (0 for A1,
>> + * A2, A3... 1 for B1, B2...); now consider also the parities (0
>> + * for A1, 1 for A2, 2 for A3); the math is done "modulo"
>> + * number of disk
>
> May I ask you to use proper English sentences in the comments?
I rearranged the comments; see V4 patches set.
>
> Daniel
>
--
gpg @keyserver.linux.it: Goffredo Baroncelli
Key fingerprint BBF5 1610 0B64 DAC6 5F7D 17B2 0EDA 9B37 8B82 E0B5
___
Grub-devel mailing list
Grub-dev
