kernel/linux.git/drivers/net/ipa/ipa_table.c, branch v6.1.168

net: ipa: only reset hashed tables when supported

2023-08-11T10:08:09+00:00

commit e11ec2b868af2b351c6c1e2e50eb711cc5423a10 upstream. Last year, the code that manages GSI channel transactions switched from using spinlock-protected linked lists to using indexes into the ring buffer used for a channel. Recently, Google reported seeing transaction reference count underflows occasionally during shutdown. Doug Anderson found a way to reproduce the issue reliably, and bisected the issue to the commit that eliminated the linked lists and the lock. The root cause was ultimately determined to be related to unused transactions being committed as part of the modem shutdown cleanup activity. Unused transactions are not normally expected (except in error cases). The modem uses some ranges of IPA-resident memory, and whenever it shuts down we zero those ranges. In ipa_filter_reset_table() a transaction is allocated to zero modem filter table entries. If hashing is not supported, hashed table memory should not be zeroed. But currently nothing prevents that, and the result is an unused transaction. Something similar occurs when we zero routing table entries for the modem. By preventing any attempt to clear hashed tables when hashing is not supported, the reference count underflow is avoided in this case. Note that there likely remains an issue with properly freeing unused transactions (if they occur due to errors). This patch addresses only the underflows that Google originally reported. Cc: # 6.1.x Fixes: d338ae28d8a8 ("net: ipa: kill all other transaction lists") Tested-by: Douglas Anderson Signed-off-by: Alex Elder Link: https://lore.kernel.org/r/20230724224055.1688854-1-elder@linaro.org Signed-off-by: Jakub Kicinski Signed-off-by: Alex Elder Signed-off-by: Greg Kroah-Hartman

net: ipa: update copyrights

2022-10-03T23:49:20+00:00

Some source files state copyright dates that are earlier than the last modification of the file. Change the copyright year to 2022 in all such cases. Signed-off-by: Alex Elder Link: https://lore.kernel.org/r/20220930224549.3503434-1-elder@linaro.org Signed-off-by: Jakub Kicinski

net: ipa: define remaining IPA register fields

2022-09-28T01:42:52+00:00

Define the fields for the ENDP_INIT_DEAGGR, ENDP_INIT_RSRC_GRP, ENDP_INIT_SEQ, ENDP_STATUS, and ENDP_FILTER_ROUTER_HSH_CFG, and IPA_IRQ_UC IPA registers for all supported IPA versions. Create enumerated types to identify fields for these IPA registers. Use IPA_REG_FIELDS() and IPA_REG_STRIDE_FIELDS() to specify the field mask values defined for these registers, for each supported version of IPA. Use ipa_reg_encode() and ipa_reg_bit() to build up the values to be written to these registers, remove an inline function and all the *_FMASK symbols that are now no longer used. Signed-off-by: Alex Elder Signed-off-by: Jakub Kicinski

net: ipa: define some more IPA register fields

2022-09-28T01:42:50+00:00

Define the fields for the SHARED_MEM_SIZE, QSB_MAX_WRITES, QSB_MAX_READS, FILT_ROUT_HASH_EN, and FILT_ROUT_HASH_FLUSH IPA registers for all supported IPA versions. Create enumerated types to identify fields for these registers. Use IPA_REG_FIELDS() to specify the field mask values defined for these registers, for each supported version of IPA. Use ipa_reg_bit() and ipa_reg_encode() to build up the values to be written to these registers rather than using the *_FMASK preprocessor symbols. Remove the definition of the now unused *_FMASK symbols. Signed-off-by: Alex Elder Signed-off-by: Jakub Kicinski

net: ipa: introduce ipa_reg()

2022-09-28T01:42:50+00:00

Create a new function that returns a register descriptor given its ID. Change ipa_reg_offset() and ipa_reg_n_offset() so they take a register descriptor argument rather than an IPA pointer and register ID. Have them accept null pointers (and return an invalid 0 offset), to avoid the need for excessive error checking. (A warning is issued whenever ipa_reg() returns 0). Call ipa_reg() or ipa_reg_n() to look up information about the register before calls to ipa_reg_offset() and ipa_reg_n_offset(). Delay looking up offsets until they're needed to read or write registers. Signed-off-by: Alex Elder Signed-off-by: Jakub Kicinski

net: ipa: use IPA register IDs to determine offsets

2022-09-28T01:42:49+00:00

Expose two inline functions that return the offset for a register whose ID is provided; one of them takes an additional argument that's used for registers that are parameterized. These both use a common helper function __ipa_reg_offset(), which just uses the offset symbols already defined. Replace all references to the offset macros defined for IPA registers with calls to ipa_reg_offset() or ipa_reg_n_offset(). Signed-off-by: Alex Elder Signed-off-by: Jakub Kicinski

net: ipa: don't use u32p_replace_bits()

2022-09-24T03:56:27+00:00

In two spots we use u32_replace_bits() to replace a set of bits in a register while preserving the rest. Both of those cases just zero the bits being replaced, and this can be done more simply without using that function. Signed-off-by: Alex Elder Signed-off-by: Jakub Kicinski

net: ipa: properly limit modem routing table use

2022-09-20T15:11:13+00:00

IPA can route packets between IPA-connected entities. The AP and modem are currently the only such entities supported, and no routing is required to transfer packets between them. The number of entries in each routing table is fixed, and defined at initialization time. Some of these entries are designated for use by the modem, and the rest are available for the AP to use. The AP sends a QMI message to the modem which describes (among other things) information about routing table memory available for the modem to use. Currently the QMI initialization packet gives wrong information in its description of routing tables. What *should* be supplied is the maximum index that the modem can use for the routing table memory located at a given location. The current code instead supplies the total *number* of routing table entries. Furthermore, the modem is granted the entire table, not just the subset it's supposed to use. This patch fixes this. First, the ipa_mem_bounds structure is generalized so its "end" field can be interpreted either as a final byte offset, or a final array index. Second, the IPv4 and IPv6 (non-hashed and hashed) table information fields in the QMI ipa_init_modem_driver_req structure are changed to be ipa_mem_bounds rather than ipa_mem_array structures. Third, we set the "end" value for each routing table to be the last index, rather than setting the "count" to be the number of indices. Finally, instead of allowing the modem to use all of a routing table's memory, it is limited to just the portion meant to be used by the modem. In all versions of IPA currently supported, that is IPA_ROUTE_MODEM_COUNT (8) entries. Update a few comments for clarity. Fixes: 530f9216a9537 ("soc: qcom: ipa: AP/modem communications") Signed-off-by: Alex Elder Link: https://lore.kernel.org/r/20220913204602.1803004-1-elder@linaro.org Signed-off-by: Jakub Kicinski

net: ipa: zero unused portions of filter table memory

2021-11-26T03:37:33+00:00

Not all filter table entries are used. Only certain endpoints support filtering, and the table begins with a bitmap indicating which endpoints use the "slots" that follow for filter rules. Currently, unused filter table entries are not initialized. Instead, zero-fill the entire unused portion of the filter table memory regions, to make it more obvious that memory is unused (and not subsequently modified). This is not strictly necessary, but the result is reassuring when looking at filter table memory. Signed-off-by: Alex Elder Signed-off-by: Jakub Kicinski

net: ipa: initialize all filter table slots

2021-09-08T11:10:33+00:00

There is an off-by-one problem in ipa_table_init_add(), when initializing filter tables. In that function, the number of filter table entries is determined based on the number of set bits in the filter map. However that count does *not* include the extra "slot" in the filter table that holds the filter map itself. Meanwhile, ipa_table_addr() *does* include the filter map in the memory it returns, but because the count it's provided doesn't include it, it includes one too few table entries. Fix this by including the extra slot for the filter map in the count computed in ipa_table_init_add(). Note: ipa_filter_reset_table() does not have this problem; it resets filter table entries one by one, but does not overwrite the filter bitmap. Fixes: 2b9feef2b6c2 ("soc: qcom: ipa: filter and routing tables") Signed-off-by: Alex Elder Signed-off-by: David S. Miller