Commit 28559959 authored by Jonas Rabenstein's avatar Jonas Rabenstein Committed by Jens Axboe
Browse files

block: sed-opal: split generation of bytestring header and content 



Split the header generation from the (normal) memcpy part if a
bytestring is copied into the command buffer. This allows in-place
generation of the bytestring content. For example, copy_from_user may be
used without an intermediate buffer.

Signed-off-by: default avatarJonas Rabenstein <jonas.rabenstein@studium.uni-erlangen.de>
Signed-off-by: default avatarDavid Kozub <zub@linux.fjfi.cvut.cz>
Reviewed-by: default avatarScott Bauer <sbauer@plzdonthack.me>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarJon Derrick <jonathan.derrick@intel.com>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent b2f9c6eb

block/sed-opal.c

+14 −8
Original line number Diff line number Diff line
@@ -580,15 +580,11 @@ static void add_token_u64(int *err, struct opal_dev *cmd, u64 number) 
		add_token_u8(err, cmd, number >> (len * 8));

}



static void add_token_bytestring(int *err, struct opal_dev *cmd,

				 const u8 *bytestring, size_t len)

static u8 *add_bytestring_header(int *err, struct opal_dev *cmd, size_t len)

{

	size_t header_len = 1;

	bool is_short_atom = true;



	if (*err)

		return;



	if (len & ~SHORT_ATOM_LEN_MASK) {

		header_len = 2;

		is_short_atom = false;
@@ -596,7 +592,7 @@ static void add_token_bytestring(int *err, struct opal_dev *cmd, 


	if (!can_add(err, cmd, header_len + len)) {

		pr_debug("Error adding bytestring: end of buffer.\n");

		return;

		return NULL;

	}



	if (is_short_atom)
@@ -604,9 +600,19 @@ static void add_token_bytestring(int *err, struct opal_dev *cmd, 
	else

		add_medium_atom_header(cmd, true, false, len);



	memcpy(&cmd->cmd[cmd->pos], bytestring, len);

	cmd->pos += len;

	return &cmd->cmd[cmd->pos];

}



static void add_token_bytestring(int *err, struct opal_dev *cmd,

				 const u8 *bytestring, size_t len)

{

	u8 *start;



	start = add_bytestring_header(err, cmd, len);

	if (!start)

		return;

	memcpy(start, bytestring, len);

	cmd->pos += len;

}



static int build_locking_range(u8 *buffer, size_t length, u8 lr)

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