qed: fix the allocation of the chains with an external PBL

Dan reports static checker warning:

"The patch 9b6ee3cf95d3: "qed: sanitize PBL chains allocation" from Jul
23, 2020, leads to the following static checker warning:

drivers/net/ethernet/qlogic/qed/qed_chain.c:299 qed_chain_alloc_pbl()
error: uninitialized symbol 'pbl_virt'.

drivers/net/ethernet/qlogic/qed/qed_chain.c
249 static int qed_chain_alloc_pbl(struct qed_dev *cdev, struct qed_chain *chain)
250 {
251 struct device *dev = &cdev->pdev->dev;
252 struct addr_tbl_entry *addr_tbl;
253 dma_addr_t phys, pbl_phys;
254 __le64 *pbl_virt;
^^^^^^^^^^^^^^^^
[...]
271 if (chain->b_external_pbl)
272 goto alloc_pages;
^^^^^^^^^^^^^^^^ uninitialized
[...]
298 /* Fill the PBL table with the physical address of the page */
299 pbl_virt[i] = cpu_to_le64(phys);
^^^^^^^^^^^
[...]
"

This issue was introduced with commit c3a321b06a80 ("qed: simplify
initialization of the chains with an external PBL"), when
chain->pbl_sp.table_virt initialization was moved up to
qed_chain_init_params().
Fix it by initializing pbl_virt with an already filled chain struct field.

Fixes: c3a321b06a80 ("qed: simplify initialization of the chains with an external PBL")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Alexander Lobakin <alobakin@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

qed: add support for different page sizes for chains

Extend current infrastructure to store chain page size in a struct
and use it in all functions instead of fixed QED_CHAIN_PAGE_SIZE.
Its value remains the default one, but can be overridden in
qed_chain_init_params before chain allocation.

Signed-off-by: Alexander Lobakin <alobakin@marvell.com>
Signed-off-by: Igor Russkikh <irusskikh@marvell.com>
Signed-off-by: Michal Kalderon <michal.kalderon@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

qed: simplify chain allocation with init params struct

To simplify qed_chain_alloc() prototype and call sites, introduce struct
qed_chain_init_params to specify chain params, and pass a pointer to
filled struct to the actual qed_chain_alloc() instead of a long list
of separate arguments.

Signed-off-by: Alexander Lobakin <alobakin@marvell.com>
Signed-off-by: Igor Russkikh <irusskikh@marvell.com>
Signed-off-by: Michal Kalderon <michal.kalderon@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

qed: simplify initialization of the chains with an external PBL

Fill PBL table parameters for chains with an external PBL data earlier on
qed_chain_init_params() rather than on allocation itself. This simplifies
allocation code and allows to extend struct ext_pbl for other chain types.

Signed-off-by: Alexander Lobakin <alobakin@marvell.com>
Signed-off-by: Igor Russkikh <irusskikh@marvell.com>
Signed-off-by: Michal Kalderon <michal.kalderon@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

qed: move chain initialization inlines next to allocation functions

qed_chain_init*() are used in one file/place on "cold" path only, so they
can be uninlined and moved next to the call sites.

Signed-off-by: Alexander Lobakin <alobakin@marvell.com>
Signed-off-by: Igor Russkikh <irusskikh@marvell.com>
Signed-off-by: Michal Kalderon <michal.kalderon@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

qed: sanitize PBL chains allocation

PBL chain elements are actually DMA addresses stored in __le64, but
currently their size is hardcoded to 8, and DMA addresses are assigned
via cast to variable-sized dma_addr_t without any bitwise conversions.
Change the type of pbl_virt array to match the actual one, add a new
field to store the size of allocated DMA memory and sanitize elements
assignment.

Misc: give more logic names to the members of qed_chain::pbl_sp embedded
struct.

Signed-off-by: Alexander Lobakin <alobakin@marvell.com>
Signed-off-by: Igor Russkikh <irusskikh@marvell.com>
Signed-off-by: Michal Kalderon <michal.kalderon@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

qed: prevent possible double-frees of the chains

Zero-initialize chain on qed_chain_free(), so it couldn't be freed
twice and provoke undefined behaviour.

Signed-off-by: Alexander Lobakin <alobakin@marvell.com>
Signed-off-by: Igor Russkikh <irusskikh@marvell.com>
Signed-off-by: Michal Kalderon <michal.kalderon@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

qed: move chain methods to a separate file

Move chain allocation/freeing functions to a new file to not mix it with
hardware-related code.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Alexander Lobakin <alobakin@marvell.com>
Signed-off-by: Igor Russkikh <irusskikh@marvell.com>
Signed-off-by: Michal Kalderon <michal.kalderon@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>